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Bfg

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About Bfg

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    Westerfield, Suffolk, England, UK
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    1940's - 1980's motors & motorcycles. Older aircraft & waterborne craft. Design Engineering. Touring & camping (in decent weather), and generally being a grumpy old giffer ;-)

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  1. . ..just finishing up on balancing the weights of piston gudgeon pin and con-rods from yesterday. . . I started off with ; pistons 8g difference in weight, and a pair of gudgeon pin 2.2 difference in weight. Matching the heavy piston to the lighter con-rod, and vice versa (as above) still left me with 5.8g difference. The lighter gudgeon pin looks to be the heavier (above right) but it is straight drilled through whereas the heavier one is drilled hollow as a taper from either end, so is thicker in the centre. The pistons themselves look to be very similar indeed, and I know that 5.8g of aluminium is physically a lot of metal to remove, so removing that much wasn't really an option. Conversely because steel is that much denser I need take less out of the gudgeon pin to achieve a better saving. So that's what I did. Starting with the already lighter pin I wondered if I might work the hole through it to be a taper ..and the metal removed would be the weight saving I sought . . . ^ I didn't honestly think it would work, gudeon pins being hardened steel an all, but I tried to used a burr bit in my cordless drill. Despite that bit being old and well used (seeing much use in my fibreglass boat) - amazingly it did cut this steel.! I steadily worked my way around the inside of either end of this pin ..which did take me three hours, but yes - it worked. . ^ the pile of grinding is testimony to that. I took 4.6g of weight out of it ..just in tapering the hole from either end. This brought the gudgeon pin down to 61g which is the same as those I'm using with Pudge's set of pistons & con-rods. My reasoning of course was that ; if just this amount of metal is good (from standard) with the other gudgeon pins, then it ought to be equally as safe to use in this engine. . ^ That's it.. I took just 0.2g out of the heavier piston which brought it down to 221.7g but paired with the 61g gudgeon pin their combined mass is 282.7g. And this is now just 2.4 heavier than the lighter piston matched to the heavier gudgeon pin. And then, pairing the heavier of these with the lighter con-rods for that engine, and vice versa.. there is now just 0.4g difference in their total weight. I can happily to accept that. Job Done.! Cheers, Pete.
  2. . evening all., This afternoon's task was to weight match the pistons and rods ..after cleaning up the second engine's pistons and rods.! . ^ Standard size and in really good condition. . ^ after general cleaning I set to with cleaning out the crud from the grooves, using a needle file. Almost no pressure is required ..after all I'm just removing the oil deposits and don't want to cut into the aluminium itself. Another time consuming task ..but tbh I couldn't bothered to get the de-carb acid out. . ^ again carefully cleaning out the burnt-on oil crud out of the oil drillings (..my last post which explains why). I'm using a 2.5mm drill bit here, and many were blocked to less than 2mm. . ^ Those in the skirt, rather than in the grooves, are at an angle. There's also a couple more to be cleaned out inside the piston (of 3mm size) which are to lubricate the gudgeon pin. . ^ #1 cylinder's piston has light scoring and pitting (from heat) from where it had seized at sometime (..perhaps when new). It's usual and this is as good as the best I've seen ..and certainly redeemable. . ^ yes I'm a butcher !! .. I used a power file to linish it down a little . ^ ..and then 400 grit wet n' dry to smooth it again. That'll be just fine. . ^ it's difficult to see from the photo but the (+0.030") piston on the left, which is from Pudge, has a much rougher internal casting with cast-in part numbers ..and their skirt thickness is perhaps twice as thick as the standard size piston from Nudge. Of course with it being oversize I cannot even guess its age. I checked the weights of these and found them to be pretty darn close. The naked pistons were 243.3 and 242.2 grams respectively and their rods with big end bolts & shells were each 342.4 grams. I'd say that's pretty good for a 1950's vintage road bike. However the gudgeon pins were odd. One was 74.7g and the other 64.6g. The standard sized pistons from Nudge's engine were 20g lighter but not quite so well matched at 214.1 and 220.0 grams respectively. Its rods (again with bolts and shells) are 349.6 and 351.9 grams respectively. Perhaps tomorrow I'll see if I can lessen these differences a bit. Again the gudgeon pins were odd, as if they had been mixed up between the two bikes ..which I can assure you they were not. But they were similarly out at 66.7 and 75.7g respectively.. Coincidental but a very similar difference in mass to those from Pudge's engine. I have a spare set of pistons and rods in my shed, so pulled the gudgeon pins from those . . . ^ gudgeon pins (in order) from three engines. Despite it being heavy-weight, the first from Pudge's engine is 1/16" shorter than any of the others. The third pair (right) are a matched pair at 61.0 and 61.3g respectively. I'll use those for one engine and the other two lighter ones for the other. They are all a good fit anyway despite there being no little end bearings on these bikes. I guess they are so lightly loaded with either 6:1 or 7:2 compression ratios. So that's it for today .. . Have a good evening. Pete
  3. Hi Azimo, likewise thanks. The bore wear is pretty even cylinder to cylinder, but contrary to the obvious - the forward one runs hotter and is more prone to seizure. I'd suggest the reason for this lies with its design utilizing the oil (return from the camshaft) running down and splashing around inside the cam-chain chimney ..which in turn dissipates heat from the rear cylinder's casting to the aluminium cases including that of the bell housing - that acts as a massive heat-sink. So whereas the forward cylinder has relatively thin cases and mostly relies on air-flow past it, the rear cylinder relies on the excellent conduction properties of chunky cast aluminium to transfer the heat away. The heat management / balance of these engines is imo very clever. Of course the real 'hot spot' is the rearmost segment of the forward cylinder where the heat between the two cylinders has almost nowhere to go. ie. the most common seizure is just above and below the gudgeon pin on the rear face of the forward piston. - - - This afternoon I was doing the same (piston ring gaps) on Pudge's engine. . ^ This was easier and quicker because it had already been rebored, so no rim around the top of the cylinders and no wear immediately below that ..so the bores are almost parallel sided. The rear cylinder is however one and half thou smaller in diameter. That's a little odd, if only because some machine shops anticipate the rear cylinder running hotter and so leave a little extra room for expansion. But this one is to the contrary. Anyway no lip meant that placing the piston rings in to check / measure them was a swifter task, because I only needed to aligned them just inside the top. Only when fine fettling the finished end gap size did I position them further into the bore.. Then I used the thickness of a nut as a 'measuring stick' for the compression rings (..so that positioned them about 1/4" down the bore), and then the same short bolt as used previously as the measuring stick for the oil-scraper rings (.. so those rings were eased 5/8" down the bore). I did have to be careful though because those Hepolite piston rings are very hard and brittle ..needing to be handled with extreme care. The difference is that they are cast iron which were machined and then surface hardened. Cast iron makes a very good spring which is also very hard, but you cannot bend it very far at all. The Italian piston rings are most probably made by rolling high carbon steel, which are then machined to shape, before being surface hardened. The springiness is less but they bend more and so are much easier to handle, without breaking. Same job but very different characteristics. Anyway that job is now done, with my following the end-gap guidelines set out by Hepolite (so ignoring what the Sunbeam Manual says). All these rings are set to 0.008". - - - As an aside, I guess this is an opportune moment to briefly discuss removal and refitting of rings to the piston. Many of you will know how best to do this, so it's just a guide for those who are new to tinkering with old motors. . . ^ Bottom oil scraper ring ..also known as oil control ring(s). The oil scrapers are wide and have double blades to scrape oil around the piston (see its shiny edges above). I gather most people think of an oil scraper / oil control ring's job is to stop oil from the crankcase getting passed and up into the combustion chamber. But that's mostly not their purpose. Actually the piston has numerous drilled holes within this groove ..purposefully to let oil into the gap between the two blades. And then as you can see there are more holes drilled between the two oil scraper / control rings fitted to these pistons. And so the rings are like oil galleries ..to route / transfer lubricating engine-oil all the way around the piston skirt and the cylinder walls. NB., unlike these solid but slotted piston oil-scraper rings (seen above) - modern ones generally have two blades and a corrugated style of spring inbetween them (to hold the blades square / in place). But the same principle applies ..of letting a controlled amount of oil splash and oil mist from the crankcase through to lubricate the piston running up and down in the bores. Anyway because these solid (rather than spring) oil control rings are wide (almost square in section) - they don't easily bend or twist. So (above) you can see me using two old feeler-gauges to slip between the piston and the ring. I carefully lifted one side of the ring out of its groove, and slipped in one of the feeler-gauges to suspend the ring above its groove. I then slipped in a second one ..and carefully worked that around to the other end of the ring. Some folk slip in a third gauge, to hold middle of the ring out of the groove while the first two are eased towards (and therefore lifting) the ends of the ring to very gently lift them out of the groove. The ring is then slid off the end of the piston. . ^ Personally I prefer not to use a third feeler gauge, but instead I carefully twist / ease the ring over the bottom of the skirt - so it can curl inwards to a smaller diameter (..less stretching to the limit) . . ^ I do the same, gently twisting over the end for the top piston rings. I find the sideways flex is more forgiving (less breakages) than stretching the ring outwards all the way around to the much bigger diameter. . ^ however the top oil scraper / control ring cannot twist / sideways flex enough, so for this one it is a matter of inserting the feeler gauges ( 0.008 - 0.012" thick ones work best) and very gently easing this ring outwards so it might be slipped upwards and over the two compression ring's grooves. Fitting piston rings is a reverse procedure. I fit this top oil-scraper before any of the others, by resting one end of the ring onto the side of the crown and gently pulling (springing outwards) and curling / twisting the ring onto the feeler gauges, before sliding it down to its groove. And then the feeler gauges are moved around ..away from the ends (one at a time) so the ring's end eases into the groove. It is a task that might benefit from having three hands (..together with a fair degree of patience) but of course is manageable on your own. If in doubt., practice with the old (worn out) rings before trying to fit brand new ones. It's really as simple as breaking twigs. . Argh.. did I just say that out loud ! With the old piston rings carefully (..I never know when I'll need a used one - in case one of the new ones darn-well breaks !) removed, I could clean up the pistons ready for fitting with new rings (already perfectly sized to each bore). . . ^ Just so many oil holes through those pistons ! Hopefully from a quick glance you'd never guess these were very old pistons ..that had been up n' down tens of thousands of times before. I even polished up the gudgeon pins (..still a good tight fit). Tomorrow I'll do the same with the other engine's pistons. That's it for tonight folks. Take care and a very good night to you all. Pete.
  4. . Just two to three hours yesterday to quickly report on. . . ^ For a 1953 motorcycle engine these bores, lightly de-glazed with fine-grit wet n' dry, are in remarkably good shape - not least because they are still to the original standard size. But as you can see from the photo they are worn. It's more visible than a hard edge, but measurements suggest there's 0.004 - 0.005" of wear. The vertical scoring lines are visible but are so shallow as to be immeasurable and not felt ..so perhaps just 0.0005 - 0.001".? The 1/4" high rim around the top is where the piston rings (which are situated part the way down the side of the pistons) don't wear. The darker colour immediately below this is where most of the wear occurs because that's there the top two compression piston rings come up to and as the conrod sweeps over tdc they stop and cock sideways a little ..and then under the full explosive power of the combustion are pushed about and accelerate away again. And of course, near the top of the compression stroke the cylinder is densely packed of air-fuel mixture, and the latter part of this dissolves lubrication on the cylinder walls. In the present circumstance of our country's lock down I can't just take the block in to the machine shop and have these rebored to +0.010", so I'll just replace the piston rings and use things as they are. Let's face it., this bike will probably not average more than a couple of thousand miles a year anyway ..so it will last another 10 years without issue, by which time I'll be in my mid seventies so I won't worry too much about squeezing every last ounce of performance. . ^ here I'm using a Demel with small sanding drum to reduce that rim's step-height. The primary reason to do this is so the piston rings, when correctly sized (tight) to the slightly worn bore, will also slip passed this lip as they are fitted with piston into the cylinder. Even if a remnant of the lip remains and it's rough - it'll not be an issue because the pistons and rings do not run on that short length. . ^ I then used a honing tool to de-glaze the cylinders. The very fine scoring the stones produce helps retain lubricating-oil as the engine is run in, and also help the new piston rings to bed in (wear to a very snug fit). With this tool, I use a cordless drill at its slowest speed (controlled by trigger pressure) and at the same time I bob it up & down ..so that scoring is at an angle to the piston rings (rather than straight the way around - which would tend to snag the rings). I use thinned engine oil (50 / 50 new engine oil to engine parts cleaner) as a cutting lubricant. Aside from clagging, this stops the grindings of metal and stone becoming airborne dust, so although it's messy - it can at least be seen, contained and more easily cleaned up. Naturally it has to be thoroughly cleaned from anywhere within the engine before reassembly. . ^ New old stock Hepolite piston rings versus Italian made ones. oh the nostalgia in old packaging. I love it. . ^ interesting that it says Sunbeam 1946 / 52, when these bikes were made through to 1956. Perhaps these piston rings were made in 1952 ? I also love the long-hand £-s-d arithmetic scribbled on the back of the packet. "Ring gaps should never be less than 0.003" per inch of bore diameter, or for racing engines 0.005" per inch measured in an unworn portion of bore" is interesting because the Sunbeam manual specifies 0.004 - 0.006" for its 2-3/4" bore. (Hepolite figures being 0.003 x 2.75 = 0.00825"). Personally I've found from experience of these engines that too tight a piston & rings tend to seize during the running-in period, so thereafter I used 0.008" for the top compression ring (which gets hottest) and 0.006" for the other three. Perhaps I ought to up my figures. The Italian piston rings don't specify any fit, but I might only presume they would expand as much as the Hepolite rings ..despite their being much softer steel (..evident when I was filing their length and also in their springiness). . ^ I use a short bolt as a measuring stick to accurately position / level the piston ring all the way around - a set distance down the bore. The length of this corresponds to the level of the top oil scraper ring on the piston, and this in the bore is hardly worn. The overlap of my 0.010" oversized rings is then marked using a fine felt pen. . . . ^ and then that is filed down (using a square sided wooden block to help keep my filing true / square). It's a time consuming task filing (deliberately cutting too little) then repositioning the ring back in its bore to recheck the measurement and also that the filing is square ..to the nearest fraction of a thousandths of an inch, with feeler gauges (below) and then filing a little more, re-measuring again, filing some more, and so on ..until the gap is spot on. BTW, the ' T ' I mark on these is simply to more clearly highlight which is the top face of the ring (the sides have a slightly tapered angle), and then I only ever cut / file the other end of the ring ..only one end is ever touched so needs to be kept square. . ^ checking the end gap with feeler gauges. Tip ; even with freshly rebored cylinders there's always a slight difference in diameter of the bores. It may only one thou of an inch (machining tolerance) but as a perimeter measurement (which is what the ring's end-gap is measuring) then that 0.001" difference in diameter = 0.003" difference in end gap. So it is good practice to measure and file your rings for the larger diameter bore. And then if you file a tad too much (perhaps if that cut didn't go perfectly square and you want to true it up), then you can use that ring in the other / tighter bore. ^ these are the Italian rings, each measured and carefully filed to size.. Each is marked to indicate which cylinder, and which piston's ring position it is to fit into. I've cut these all to be 0.005" end gap in accordance with the Sunbeam Workshop Manual (seeing as these bores were already worn near their top) but after reading the instructions on the Hepolite packaging, I think I'll go back and ease them just a little. Pete. .
  5. ^ Thanks, I'm glad you also think so.
  6. . Me Big man.. me make big mess in kitchen ! ^ a quick check for flatness of this sump's gasket face reveals a corner not sitting flat by 0.003". . ^ 320 grit wet n' dry taped to the flattest part of this kitchen worktop ..and with a little elbow grease + soap n' water - its gasket face was trued up a little. * I use a felt pen (waterproof ink) as a very convenient substitute for engineers blue. It works well. ^ the sump's gasket face is now very flat aside from a dint ..right next to the middle stud hole in its forward end (to the right you can see what looks like a black dot). As engine oil might seep passed this and out through the stud's hole - I'll fill that dint with a spot of Araldite. The new spacer was as flat as any I've yet bought and was generally fine after a few minutes work, aside for a slight low cut (see blue across either end). It been milled but this one cut was perhaps a thou deeper. A bit more work on the wet n' dry pad took the surrounding aluminium down so it's barely discernible now. So I moved over to checking the rocker cover's gasket face and that of the engine's timing chain inspection cover. ^ the rocker cover I had done before and so this was more a check than anything. And this particular cover is in excellent condition. Sadly I've come across so many which have been abused over the years with careless handling, over tightening of the three studs (which cracks the casings and then need welding), and most are badly bowed. Some I've known to have 0.035" or more distortion. This one shows a little hogging, but it's now less than a thou, so as I double up on the card gasket I use here - I'll leave it as is. The gasket face of the little inspection cover though is pulled down at every fastening hole. I could slip a 0.006" feeler gauge inbetween the worktop and gasket face, in the short span between the holes. That's more than the gasket can take up, so it must have been leaking badly when last use. Awkward little so n' so to hold down and rub against the wet n' dry., but little by little it succumbed to the threat - be flat or be scrapped ! So, only an hour of work today ..but an hour in the right direction is better than non at all. ......even if it take me a further half an hour to clean the kitchen again ! Pete.
  7. . This afternoon I carried on from the above ..catching up on the second engine. . . . ^ the problem with studs is that if any of their holes have been drilled off-perpendicular to the gasket face then the stud either splays sideways or in or out ..relative to the others, so then the drilled castings of the sump &/or sump spacer wont slide over them. Of course the longer they are.. the more out of true alignment their free ends are. Mostly this can be corrected by judicious filing of the holes in the sump and sump extension . . . ^ The red felt pen ticks indicate where the stud fouls in the hole, in this case - preventing the sump spacer from going on. So here (in this photo) I'm using sideways force on the drill bit to ease the hole in the direction of the tick. These sump spacers have slightly oversized holes., but even so they needed filing or in my case drilling sideways to make it fit. The cast sump I'm using was not original to this engine, and its drilled holes were a tighter fit to the studs, so a time consuming amount of rework was needed. . ^ this particular stud's hole was drilled and tapped at a slightly wrong angle, whereby the free end of the stud out of alignment by perhaps over 1/16". After fitting and marking which way it fitted in the hole - I took it out again and bent it ! This is that same stud, now refitted. You can just about see how its bent (its shape sprung back some after being altered in the vice). The end tip of the thread is now in alignment with the others, but of course it is still bowed out, but by only half as much as its end previously was ! . ^ It took me a couple of hours to alter the spacer's and sump's holes to fit these crankcase studs. Even now some are an interference fit - but those parts can be wiggled off ..by hand rather than needing wedges to free them. Once in place there's just a little slack on the studs - so the crankcase's holes were all drilled in the right place ..just not at the right angle. That part of the job is now done, but to my eye the spacer looks slab-sided and so ugly, relative to these otherwise beautiful crankcases. . . ^ pencil marked to be cosmetically altered . . ^ carefully done all the way around, except in the area of the sump's drain plug ..and I do this simply to know which way around the spacer is orientated. If fitted the other way around - my filing to suit the stud pattern doesn't work and the sump itself won't align so neatly with this spacer ..as its holes have been drilled just little towards one end. . ^ widening that hacksaw blade cut with the corner of the file to form a v-shape groove. ^ and then rounding that v-shape groove into a shallow U shape. The finish isn't critical, but any neater and it looks worse ! ..because the castings of the engines cooling fins are never perfectly straight nor smooth. ^ that's it. A whole lot of work to file a shallow grove approximately midway down the slab face of the spacer. The proportions are reasonably compliment to the spacing of the engine case cooling fins ..and so after a few months on the road (when all the aluminium has oxidized evenly) then it will not even be noticed.! But to my mind - it is the details that you don't see which can make the difference between something looking right or something looking just a little odd. Enough of my prattling on today. I bid you a good evening. Pete.
  8. . Good afternoon all. With so many other distractions, not much has been happening on the bench this week ..but here's a little conversion I do to the oil filtration on my old Sunbeam motorcycle engines. . . . ^ The engine block (in aluminium) with the original filter ..the oval shaped brass top with gauze mesh around it, soldered onto a base plate. This plate (when inverted so the filter is facing downwards) is sandwiched (hence two gaskets) between the block and the cast aluminium sump (top right). The plate has a few through-holes, but they are not so large because it also serves as a baffle between the turbulence in the crankcase (with the crankshaft spinning around) and the wet-sump oil reservoir. It would helps stop the oil in the sump from surging forward ..away from the oil pump's pick-up pipe, under heavy braking. 'heavy' being a relative term with 1940's drum brakes, but perhaps the oil surging sideways is also a matter for concern when the bikes are used with a sidecar. To the left is a (HOF306) disposable paper element oil filter ..which I now use, along with viton o-rings. Seen at the bottom of the photo is a spacer made and supplied Stewart Engineering, who are the primary supplier of post-war Sunbeam parts ..and I believe owners of the Sunbeam Motorcycle name and its design copyright. The 'sump spacer' is supplied with new gaskets and x12 longer studs. It cost the best part of £100 + p&p ..but is (sort of ) useful because it increases the standard (3-1/2 pints) engine oil capacity by an additional pint. However, the spacer fits between the baffle plate and sump casting, so unless one extends the pick-up pipe, that extra pint of oil just sits in the bottom of the sump. True it does general mix in with the oil being circulated - but it does NOT add to the oil capacity that is accessible to the pump. So, should the oil run low, the pump will still suck air (despite still having that extra pint in the sump). Why is the spacer not fitted lower ..between the spacer and the sump casting then ? Well, without extending its pick-up pipe down to the bottom - the pump would suck air at the same oil level. The gauze filter has a soldered-on collar to snugly fit around the pick-up pipe. This is not insurmountable but it would need to be removed for an extension tube to fit through it. More the question is - how well would the baffle plate work with so much engine oil above it ? I suspect that oil would literally be driven up the walls by the turbulence within the tight confines of this crankcase. So., I change things. I leave the baffle plate where it was designed to be but I extend the oil pump's pick-up pipe. . ^ This shows the standard oil pump's pick-up pipe relative to the inside of the sump ..this is without two thick sump gaskets, the filter/baffle plate, or the after-market sump spacer. There is about 1/4" between it and the bottom, but because of the notch in that pipe - the pump would suck air if the oil locally surged away to be less than 1/2" deep. " Well that's a ridiculous low level of oil " you might rightly say. But let's do the maths (on these little engines). We'll start with a (standard) full capacity of 3-1/2 pints, and then there's, let's say, 3/4 pint of oil needed to fill the oil-ways, cavities and galleries throughout the engine, and then when the engine is running there's another 3/4 pint being splashed against / running down the insides of the cylinder head, rocker cover, timing case and crankcase. And the 1/2" air-gap between the sump and the top of the notch in the pick up pint constitutes another 3/4 pint, so also does the distance between the top of dipstick mark to the bottom mark (ie., conceivably less another 3/4 pint). So we have 3-1/2 pints, less 3/4, less 3/4, less another 3/4, and less yet another 3/4 pint = 1/2 pint reserve ! Is it not feasible that this (= just 3/8" deep) might surge under braking or when a sidecar bike turns quickly through a fast corner ? . ^ illustrating the crankcase, and sump, relative to the length of the oil-pump's pick up pipe with the sump spacer fitted. The shiny tube I'm holding up to it is a length of aluminium which I'll use to extend the pipe by the spacer's thickness (21mm). . ^ The aluminum tube I use is an interference fit, on which I use Loctite but then literally hammer it on. . ^ With the sump spacer in place, but still without x2 thick gaskets and the filter/baffle plate, I've reduced the clearance between the sump and the tube to about 1/8". . ^ I then cut the bottom at a 45 deg angle so there's no restriction to oil flow, even if the tube should happen to work loose and drop down. . ^ The pipe is now cut, de-burred and thoroughly cleaned out, and I'm fitting the new / longer studs. . . . Moving on to the engine oil filter itself.. whose casing would stop my extended pick up pipe reaching the bottom, and otherwise has too coarse a mesh to prevent fine contaminates (byproducts of combustion and running-in engine wear) from circulating. . . . ^ the solder around the front of this one happened to be cracked anyway. . ^ Blowtorch used to un-solder it. I leave the two anti-surge plates in situ. . ^ cleaning off the surplus - it's surprising how the weight of this adds up. . ^ Ok cleaning up job done. two new holes (red arrows) have been drilled and I'm just about to add a piece of aluminium angle - longitudinally to the top face of the plate. This is to stiffen the plate against panting ..in a small crankcase which changes in volume by 500cc with every half revolution, and might also help with lessening the amount of oil being driven up the inside walls of the crankcase by the turbulence from the spinning crankshaft. . ^ Here I'm checking a length of rubber hose I've cut to sit between the crankcase and the baffle plate. It effectively seals around the hole through the plate and acts as a spacer to (again) prevent that plate from panting. .. ^ Working on two engines at once. That on the left shows the extend pick-up pipe with rubber hose sleeve around it. And the engine to the right shows the sump spacer in place and illustrates how the disposable filter fits. (NB. old sump gaskets are only used for dry assembly trials, and not for the final build). A fair bit of filing was done to have the plate and the sump extension sit down on the studs, as those (although original) are not perfectly parallel. . ^ detail showing my extended oil-pump pick-up pipe inside the disposable filter. The cast finish on the inside of the sump (seen in first photo) has been locally smoothed, so the o-ring forms a seal between it and filter, which is sandwiched in there. The baffle plate is of plated steel - so I'll also place a strong magnet on it. Because of it's size and shape, it can't go anywhere but in practice I've also never known one move about. . ^ The sump loosely dry fitted in place. And unfortunately yes, the sump does have to be removed to change that filter, but so did it when needing to clean the original gauze. Once after 200 miles of running in and thereafter every 3000 miles is not such an issue with a wet sump design. And of course, the oil itself may be changed frequently without dropping the sump. . ^ viewed of the aperture for the rear bearing carrier ..which also carries the oil pump and oil way galleries. The hole between the two studs at the bottom of this flange face is where the oil pump draws the engine oil from the sump, via the pick up pipe. And the hole through the flange near the top is where the oil-pump sends the pressurised engine oil up to the camshaft. Inside the case you can just see the upstanding length of aluminium angle used to stiffen the sump's baffle plate and to hamper oil being driven up the inside wall of the crankcase. In this morning's post I received a second sump spacer from Stewart Engineering, for the other engine. . . . ^ Actually it's a nice casting, but their instructions neglect to say it needs finishing. It's a raw casting and so the gasket faces are not smooth, and more often than not these castings are not flat ..but is often slightly bowed &/or twisted - so it needs flattening on both sides before it will be oil tight. Often the holes need easing too, but that's because these Sunbeam engines were made on 'very tired' war-time machines. Personally I also find they look slab-sided when fitted - and so, as you see in the other photos, I file a grove all around it's outside, which (visually) halves its height and imo compliments the lines of crankcase cooling fins. That's it for today - it's time for me to do some flatting and filing ! Best regards and take care, Pete.
  9. Bfg

    Home made pick ups.

    ^ complete with bird bath.. Triumph owners are such a nice bunch
  10. ^ I provided the con-rods with shells only for the big ends to be reground to. But the mains were not meant to have been reground so the machine shop never had the engine block, caps, or bearings to measure or work from. The official workshop manual says ; Main Journal Dia.: 2.4790 - 2.4795". Today measured the front journal at 2.4675" = which according to my maths is not the 0.010" increment, but rather is a 0.012" difference. Admittedly my measuring with digital vernier calipers is not so accurate, but my previous pressed-tight measurement recorded a 0.013 - 0.014" difference ..so I might only hope that my calipers / each of my measurements are way out. Again I'll have another engineering company check them for me, but the fear is that the machine operator removed 0.010" from whatever he measured the part-worn journal size was ..rather than referring to workshop manual. I loathe the prospect of dragging this through the courts but just in case - does anyone know of a lawyer who is very good with cases like these.? Pete.
  11. . Finally I got my Triumph engine parts back from the machine shop. But to be honest - I'm of mixed emotions ..because things were not exactly as I had expected. . . Cylinder head ; now has been pressure tested and the core plugs replaced. It now has hardened exhaust seats, re-cut inlet valve seats, NOS valves (all of them), NOS valve guides, and the cylinder-head gasket face has been skimmed. Good news is that it's now good to go (..I hope), unfortunate news is that the original valve guides were a better fit than these. I thought those from #3 cylinder, and possibly one of those in #4, were a little loose and so might need replacing - but instead they went ahead and changed them all ..and now the all valves feel as loose in the guides as those to #3 cylinder were.! As you see I haven't yet unwrapped the cling film - so I also haven't visually checked the valve seats or the job done. I guess next week I''ll do this and also refit the valve springs so that I might do a drain-down test ..just to ensure the valves are well bedded in. Aside from replacing all the valve guides, I also didn't ask them to, nor want them to skim the gasket face. I simply asked them to check it for trueness and to advise. I have no reason to suspect the old gasket had any issues so if it ain't broke - don't try to fix things. I don't know how much has been skimmed off but I had no desire to increase the compression ratio. I'm not overly happy. Crankshaft ; journals reground to 0.010", oil-way drilling plugs removed and cleaned out inside, and crankshaft assembly has been balanced.. But......... I specifically didn't want the main bearing to be reground. (only the big-ends). The mains didn't need it ..and I so bought original manufacturer NOS main bearing shells of a standard size ...Which Now Don't Fraking Well Fit ! That has me well and truly 'upset'. Balancing . . . Having seen the job done on Mike's (another TR4 owner in the TR register) crankshaft - which necessitated his having to buy a replacement ..because his had been previously 'balanced' so badly and was beyond retrieving - I now see this in mine. I fail to see how so much needed to be removed from the balancing Triumph had originally done ? It gets worse on the other end . . . ^ blue arrows indicate original balancing notches, the two red arrows indicate where these corners has now been angle-ground away. The one has actually cut into the ground side face of the journal. Again, I fail to see how so much needed to be removed from the balancing Triumph had originally done ? I am of a mindset that they have done the same damage as Mike's crankshaft endured.. and that this crankshaft is now scrap. I may be wrong but I really don't think so. But to be sure - I now need to take it to another company to have it checked. Flywheel (right) is good (I think) and I am pleased. As requested - they turned the outer edge of the TR3 flywheel ..to reduce its overall diameter and to take the bolt-on TR4A starter gear ring. I'm told its metal was very hard indeed. With its starter ring, this is now 17lb in weight. As the standard spec was 31lb - I'm very happy with that weight saving. The flywheel seen here on the left is an already lightened TR4 one (which I borrowed for dimensions) which weighs in at 19lb. The gear ring weighs 3lb so altogether = 22lb. I would have been happy with that but it was not mine ..which is why I bought the TR3 one and had it reworked. The TR4 flywheel (left) is drilled for the 6-spring type clutch, my TR3 one has now been drilled for the diaphragm clutch. It was balanced independently and with the crankshaft. Overall the bill with VAT was £40 less than anticipated (all in all very close to £520 total), but until I know that crankshaft has not been ruined I'm left worrying. I also need to check dimensions and to find myself a set of +0.010 main bearing shells, so the final bill will end up more. Oh., and I need to drive back to the machine shop because they still have my con-rods and big end shells. My mistake as much as there's I should have remembered. There was no work to be done on them (I had weight matched them myself) but I supplied them so they might measure for themselves the exact big-end journal size required. That's all for tonight. Pete.
  12. . I've mainly been doing other stuff this week so just a little to update.. ^ A bachelor's home.. Mine has elements reminiscent of a production line. The two engine blocks of the engine's I'm rebuilding. Both I've tidied up in regard to filing the cooling fins and around the edges to diminish the appearance of knocks and scrapes incurred over the past 67 years, as well as some pretty awful original casting blights on the later case. The other / older one (to the right) was professional bead blasted, and will be used in Pudge ..the S7-deluxe Coronation window-display bike. The original to Nudge block - is the one I chemically cleaned and then used a scouring pad and degreaser on, and then last weekend - cosmetically disguised its broken top fin. Now there's not nearly the visual difference as it may appear here ..due to uneven lighting. ^ what I'm doing here is sorting / checking I have the components for each engine, along with all the correct fastenings and gaskets etc. It may seem obvious to keep all one bike's bits together, which on the whole has happened but these engines have been dismantled for quite a time now, and Pudge's was dismantled by someone else (..page 2 of this thread), and subsequently each box has been rummaged through looking for bits from Hovis which I sold in April springtime last year (page 4 of the is thread). The paper-type Oil filter is not standard, but is another little conversion I like to do on my own Sunbeams. I have to convert Nudge's engine yet so I'll come back and share details of that modification in a week or two. ^ Timing chains. The top of the three shown is a new one which illustrates how little it flexes sideways (no wear in its pins or links). The middle one is just slightly worn, and the bottom one is plainly just worn out. So there you go, as I say not a lot to report on this week, but enough "little steps at time" in the right direct ..and progress will finally be made. Wishing each and all of you a good weekend, Pete.
  13. ..subsequently learnt of this . . Araldite® EP 300 A/B Adhesive is an extrudable, two-component, room temperature curing epoxy adhesive designed for service temperatures up to 400°F (204°C). This product is suitable for bonding a wide variety of materials such as metals, composites and many other dissimilar substrates.
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