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Grogee's spannering (Puma, Maestro, 5er & Corsa). OPERATION CLUTCH


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'Found' a free afternoon where Mrs Grogee wasn't hassling me to pack stuff for the move, although we'd spent yesterday and today clearing shit out of the garage. 

I decided to tackle the iffy rear brake which I couldn't get any fluid out of. 

Took the drum off, shoes off then clamped the flexi hose and removed the old wheel cylinder. Luckily the brake union didn't decide to go all twisty with the brake pipe. 

Not sure what was wrong with old cylinder but I managed to bleed some new fluid directly though the pipe, so there's no blockage there. 

My replacement cylinder was luckily the right size but unluckily the wrong 'hand'. Fortunately it's so old school that I was able to pull the pistons out and swap them around, making it an RH version. 

Fumbled the cylinder back on then the shoes on, again old school stuff is so much easier to manoeuvre into place. Lots of cleaning and copper grease to keep things from seizing up, then adjusted the handbrake adjuster to something approximately close. 

I've also changed part of the handbrake cable; a new one came with the car. The plastic 'outer' part is slightly longer than the one that came off but I'm hoping that won't matter.

The green spring clip attaching it to the backplate had me foxed for a bit but I poked and prodded it until it gave in. 



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Got the manifold off but in doing so I've now created new and exciting problems with at least two broken studs in the head. 

Not quite sure how I'm going to tackle this because I think the area behind the head is impossible to fit a drill into. 

I've got a right-angled drill whatsit which might do the trick, although from memory use of that tool required at least three hands.

If I can't get at the stud then it's head off, which I could really do without although it would allow me to do a good de-coke and stuff; I'd probably get it skimmed as well.

Tomorrow I'm going to the scrap metal place to weigh in some stuff. I did alright last time, £40 or so for some old discs and alloy wheels. I've got loads more this time so I'm hoping it'll be enough for a cobalt drill bit set.

IMG_20221017_122021194 zoom.jpg

IMG_20221017_122102035_HDR zoom.jpg



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Thinking about the studs and fixings for the manifolds, they appear to be M8 but I'm a bit wary based on the fact this is BL, O-Series and dates from around the time of the Norman Invasion.

Shirley at least some of the hardware in an O-Series will be imperial threads?

Also, does anyone want to weigh in on the unleaded v valve seats debate - Wikipedia says as below, but the car has come with some Redex lead-replacement fuel treatment, which makes me think Wikipedia is wrong. 

Handbook says use 4-star but seeing as I write handbooks that's the last source of information I want to use!

2-litre O series[edit]

A notable advantage of this particular O-series engine is that the cylinder head does not require modification to run on unleaded petrol due to having hardened valve seats. Other O-series engines, however, cannot run on unleaded without modification of the cylinder head or use of an additive.

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We're beyond the ability of two nuts to move these studs. 

I've just been in garage attacking the zorst manifold and interestingly my impact stud remover thingy managed to free two of the three stuck studs. 

This is after liberal application of 'farmer fixing juice' (acetone and ATF) over a couple of days, then heating each one with a blowtorch.

The impact remover thing actually worked alright but on one of the studs it just chewed the end down to a sad nub. I ground it flat then drilled it out and re-tapped.

Fortunately I have a few M8 studs in Stores so they've gone in after I cleaned the gasket faces up with a grinder sanding wheel thing. 

While that was out, I cleaned up the faces on the aluminium inlet manifold too (gently) and I'm halfway through making a throttle body gasket that is NLA.

What I'm actually doing though, is procrastination. Because I don't want to recognise the probability that to get that stud out means taking the head off. 

Because the manifolds are at the back of the engine, there is limited tool space to drill out the stud that's flush with the head. That, and I will need a very steady hand to drill into the stud (the head is 'high-tech' aluminium). Hard enough on its own, but harder when you're lying on your back or lying on top of the engine. 

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Success, I think - unless I've accidentally drilled through a waterway.

I've got all the busted studs out but had to resort to drill & tap method. Scary, because of potentially borking the head due to drill slippage. 

After a morning of plonking about with reverse drill bits, I seem to have reached a place where the manifolds are ready to go back on. 

Had to 'aside' the fuel rail and wiring first, spilling lots of fuel, then remove a rusty coolant pipe - spilled lots of coolant too.

I may replace the pipe with some copper pipe if my semi-employer has the right size and a bender. It's right next to the zorst manifold so it'll get toasty hot, I'm not sure even high temp paint will do the trick there. 

I did try the stud remover on the sticky-out broken stud but again it just chewed it up - this, after heating the funk out of it with blowtorch. I had a bucket on standby in case of spilled fuel ignition...

Anyway I just need to make or find another stud to go in then I should be ready to bolt back together. Need to clean out manifold first as it's full of swarf from cleaning the faces. 

Still a lot of work to do to get it running again but feeling better that head doesn't have to come off. 





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Been sorting out some parts cleaning and painting for Maestro. There are two struts between manifold and block, plus a steel coolant pipe that runs next to the zorst. All of them have got too hot and the paint has peeled so I've cleaned them up with the wire wheel and given them a coat of high temp paint. I've only got blue, so that'll have to do. 

Had a look at the throttle body. Weirdly it doesn't open the throttle butterfly fully, so I've ground off the stop a bit so it now turns properly horizontal to the flow. That'll be worth an extra 0.05bhp. 




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It's back together, so the logical move now is to take it apart again.  

Wait, there's method to my madness... I've drained some coolant in taking off that rusty pipe, so I may as well drain the lot. I've got a new wasserpumpe to go on, which requires cam belt off, which I've also got. No idea when it was last done. 

As luck would have it, the stars have aligned and the engine is at or near the timing marks so that's the universe's way of telling me I should do it now. 





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So I've pulled the belt off. Also reverse flushed radiator and block, that felt good. Not too much gunk came out but I think it's good to do 'while you're in there'.

The belt and tensioner arrangement is very straightforward, as usual no visible damage to belt but the tensioner had gone rusty, although it span ok. 

I've bought the wrong water pump and it seems replacements are impossible to get. Well, impossible or £80. There are a few different variants and it seems I've bought a diesel pump. Block fitting is the same but the elbow is different. 

Not sure whether to bodge the diesel pump on there and use a selection of generic 38mm pipe fittings, or fork out for the right part. 



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More pratting about today. Cleaned up gasket faces ready for the correct new pump, it's an eBay special from a person not a parts company so I'm hoping it won't take an age to arrive.

I couldn't help but feel sorry for the oil catch can at the front of the engine. It's been wrapped in pipe lagging (why?) which has done a nice job of keeping the damp next to the steel, it looked very crusty indeed so I've beaten that rust into submission with the whirlybrush. I'll be applying a few coats of Wrong Blue to it in the hope it'll slow the rust down. 

Yesterday I took the thermostat out to flush the system so I've been making a new gasket for the housing, and I'll throw in a new stat for the sake of £5.


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This morning I got a pass-out to do a couple of hours tinkering. Re-sealed the catch can (now painted Wrong Blue) onto the sump with new home-made gasket and RTV sealant. Same treatment to thermostat housing, popped new stat in and sealed the top down. 

ETA for the new wasserpumpe is Saturday which seems an impossibly long time seeing as it was posted yesterday. Is there another RM strike?

Next up, I are be mostly wire-wheeling the bodywork at the front, under the radiator but to the sides where it meets inner wing/chassis. It's looking a bit crusty but luckily won't be visible if I clean up then paint over with zinc or matt black.

We're moving out soon, probably around 12th, so that's the 'drop-dead' date for getting this running again. The non-functioning indicators will have to wait, it just needs to be mobile to get over to bodywork place for an estimate. 


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Got the angry wheel out again to treat some rust that was starting at the front. It's not terrible and I could have ignored it but I'm taking the view that I should do stuff 'while I'm in there'. In this case I'm doing the water pump and the rust was bugging me. 

Managed to spill some zinc primer onto the brick driveway - sorry new owner. TBH it's a mess from various spills and fluids I've dropped while working on shiters.




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Pump and belt back in but rain stopped play before I could finish. Tensioning the belt was basically a total guess. Doing it properly requires a tension gauge which I don't have. So I just went for 'about right' on the thumb meter. Did a 720 on the crank bolt and it seems ok. 

I was pleased to receive the pump so soon, it was posted Saturday. But I couldn't find a gasket so I went about making my own, something I've had to do a lot lately. Not trivial because you can't rest the sealing surface onto the paper because of the impeller jutting out.

Eventually I sort of cobbled roughly the right shape, then when I went to put the scissors back I noticed something on the kitchen floor... The original gasket had fallen out of the package onto the floor! Ah well no harm done, I've got a spare now. 

Because the Maestro dates from ages ago, the handbook isn't too specific about which coolant to use. However I've got some 'red' which ought to do the trick. Book says 33% antifreeze but I think I'll go for 50% for better corrosion resistance. I'm not bothered by ultimate cooling power as I won't be ragging it around a track. Also, I've reverse flushed the rad and block which should help. 





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2 hours ago, grogee said:

Because the Maestro dates from ages ago, the handbook isn't too specific about which coolant to use. However I've got some 'red' which ought to do the trick.

Red stuff (organic acid) doesn't always play nicely with older seals and materials (including brass heater matrices, for example) - I'm not saying OMG IT'LL DIE, but it'd be worth reading up on it because this car will have been specced for glycol (blue) back in the day.

And obviously, never mix 'em. They make a gel.

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bottled it and heeded @mercedade's advice, I've bought 5l of Bluecol's finest ethylene glycol concentrate (based on the fact I'm bound to need more in the future).

Are there any shiters near Rayleigh (Essex)? I've bought 2x cheesegrater wheels which I can collect from (relatively) nearby Northants. There are 2 more in Rayleigh. One is pretty crusty but I know a man who restores alloys.

I used to live in Billericay but unfortunately I can't go back in time to ask Past Me to collect them. 


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7 hours ago, Noel Tidybeard said:

now you are sure those wheels are MG 14" cheesegraters and not VP 13"?

Says 5.5J x 14" on the ad.

The coolest wheels for the Maestro, by a country mile, are these ones. But they are metric, which is simply a pain in the ass so I'm not bothering, even though there is a set available on the bay. 


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Good news:

It runs. It hasn't leaked anything out yet (except exhaust blow - see below). It got up to temp and the fan comes on.

It sounds properly fruity. The s/s zorst I put on must be a sporty number; I'm pretty sure it's bigger diameter than standard: https://youtube.com/shorts/DD-MyJaKeXY?feature=share

Heater blows hot to feet and screen, but not face vents. Is this normal?

Bad news:

The Chinese relay I put in doesn't switch fuel pump on, so I'm using the butchered original that works but flattens battery if left installed. 

There's a blow from where downpipe meets zorst. Going to try slapping some more fire putty on and re-seating the clamp.

There's a 'zizzing' noise from around front end, alternator or water pump, or oil pump I think. Maybe it was doing it before, I honestly don't know as it was weeks ago I last ran it. File under 'wait until it breaks'.

Next up: NSR brake binding & new handbrake cable. 



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Strike while the iron's hot! Or at least while it's not raining. 

The drum came off after a tickle with the persuader but I think the cylinder was seized. I couldn't move either piston once the shoes were off. Luckily I had a spare from a bargain NOS purchase so slapped it on and bled out the brake. 

The handbrake adjuster was also seized so I've freed it up and it's fine now. The cable is a bit of a bugger though, I need three hands to compress the spring while I connect the cable. @Cluffy to the rust arena, please. 

In two minds whether to replace the main handbrake cable - I ought to test it and see how stiff it is really. I do have the part (well it appears to be the part) so I could do it 'while I'm in there'.



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13 hours ago, grogee said:

Says 5.5J x 14" on the ad.

The coolest wheels for the Maestro, by a country mile, are these ones. But they are metric, which is simply a pain in the ass so I'm not bothering, even though there is a set available on the bay. 


they look same as montego GSi wheels with different centre caps and i don't remember mine being metric!

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Met a nice old chap called Glyn this morning, collected these two wheels off him. He showed me his collection, he has a later MG Maestro - also in white but with colour coded body kit, very nice. Also in his man cave was an Austin/MG 1100 which looked very tidy indeed. I took the opportunity to note down his preferred body repair person - Northants is a half hour drive from me but he sounds better value than 'grumpy Tim' who I use. 

Nice to share stories with a fellow addict, and he seems quite active in club circles so a good bloke to know. 

The tyres on these wheels are decent but non matching, a shame because I don't expect I'll find another Goodyear Eagle NCT or Bridgestone RE71 in 185/60 14 any time soon. Same story with my spare, an immaculate (and hardened) Pirelli P6000 from Back In The Day. #tyrenostalgia 


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More faffing about with the handbrake cable. I mistakenly thought it would have to be disconnected from the handbrake lever to replace it, so I spent ages removing the centre console to unhook it.

That involves (unbelievably) partially removing the front seats, the whole thing was a clusterfuck of back-breaking fiddling really. 

There was another reason to remove the centre console. The gear gaiter was hanging off unattractively. Turns out it's held in the console with six tiny self tappers into ancient, brittle 80s plastic. Yeah, the raisers failed immediately when I tried to combine the good gaiter and good console. Solved this by drilling 2mm holes through and bolting it with M2 bolts and nuts. 

Anyway, new handbrake cable is on. Hopefully I'll get an hour or so tomorrow morning to refit the rear brake shoes and drum, then I can finally let it off the stands and drive it to Grumpy Tim's for an estimate on body repair. 

Haven't got any pics but I did like this low sun shadow of a bird on my roof, so have that instead. 


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  • grogee changed the title to Grogee's spannering (Puma, Maestro, 5er & Corsa). OPERATION CLUTCH

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