'A' Series engine repair

[Squire_Dawson]

I wonder if there's any interest in an engine repair thread. This is an 1100 unit salvaged from a scrap car which will be put into mine. It has been dormant for at least 10 years, probably 15 or more, and before fitting it, the obvious health checks need to be carried out. So, let the strip down commence. First of all, I need to remove the caked on muck. Curiosity got the better of me however, and I ended up removing the rocker cover instead to have a look. Inside was not a pretty sight. Some of the valves are stuck. But at least the engine still turns freely.

 

 

 

 

Plus gas comes in very useful on such jobs.

 

 

***BONUS Scammel***

Papped by a mate of mine.

[AlabamaShrimp]

Me interested please! I've taken very broken engines at college apart but I know that's nothing like real life.

 

As I'm wanting to have a mess with my mk1 Fiesta this might give me a clue what to do

[MarvinsMom]

MOARE PLEASE!

[Grundig]

I too like engine strip down & rebuild threads 

[The Moog]

Yes please mister....

[MrBiscuits]

Yes Please....

 

One of these remains the only engine I ever properly rebuilt - in my parent's shed circa 1997.

[beko1987]

Very much yes please!

[tinribs]

I put my hand up too

[forddeliveryboy]

So it's a big YES! From me too, fire away!

[Squire_Dawson]

Right ho, I'll keep you posted of progress.

[mercrocker]

Look forward to it.....Reckon the time is coming soon to flip the top open on mine.

[stephen01]

cant wait to see the progre

[doobietoo]

+12345678910 I have built a few but you never stop learning and I am looking forward to seeing all the little tricks that make things easier...... No pressure lol

[lisbon_road]

I've rebuilt plenty but if you can be bothered with uploading pictures it would be fun to see and as doobie says - you always learn something.

[CHRIS1980]

Did this come out of an Allegro?

[Squire_Dawson]

Aye it came from an Allegro, which makes it easier as it's a like for like swap. So, progress. This breather hose is obviously past it, but I'll keep it for reference so I can cut a new one.



Removing the manifold, some nuts were hard to access.




With an extension drive it was easily got at. All I have used so far are open ended and ring spanners and sockets with various drives. Everything on this engine is AF threaded, the most common sizes 1/2" AF and 9/16" AF.


The manifold was removed with the carburettor still attached, which will be dealt with later. Just a little gentle persuasion with a rubber mallet broke the bond. It was carefully withdrawn using both hands as it is heavyish cast iron, which can be very brittle. So caution is needed when handling cast iron pieces, especially rare parts, which if they break are usually unable to be repaired.




Now, the thermostat housing, another part which is getting hard to find and can be very difficult to remove. Copper grease on the studs stops things seizing up. Here we can see the furred-up outlet. Fortunately the top came off easily enough, again just tapping with the rubber mallet to break corroded bonds. The sandwich piece, which takes the pipe to the heater, is stuck for the moment and is something else to be tackled later.



Rocker gear was removed, another simple job just removing nuts and washers. Note that some of the cylinder head studs are here.




Head off! Not a pretty sight but beneath the grime all appears well. The liquid on the piston crowns is Redex I had poured through the sparking plug holes. I will explain more about what to look for here in a future post.



The stuck valve. Given the state of this head I am not going to tackle it myself. A professional will be giving it the works including hardened valve seats for unleaded petrol.

[Squire_Dawson]

I will sort the upside-down photos.

[mercrocker]

Good stuff, Squire - got a feeling my head's gonna look like that when the time comes.....

[seth]

Soaking in Plusgas and lots of heat from a blow torch might get that thermo sandwich plate moving.  

[blguy1975]

Great thread Squire,More photos ,,Do a good Job and I may hire You re build Hectors 1275

[Slartibartfast]

Love this sort of thing. Definitely will read more.

[oldcars]

Loving this. You make it looks easy. I have been doing the head on my Reliant but i'm awful with the photos. 

[Squire_Dawson]

Where was I? Ah yes, dismantling an engine... I have been working on it when I had the chance and taking photos. So to resume...

 

The cylinder head came back to me 'as good as new' with all the work done, which means I can forget about valve problems for many years now (I just hope the rest of this engine is OK!) The total cost was £175, which I think is money well spent.

 

Had a look at the head gasket, as they can be re-used if in good condition. This showed signs of blowing between cylinders so I threw it out. No point risking it after going to the expense of a 'new' head when a gasket costs comparative pennies. I only buy head gaskets of the copper type, the new one was made by Payen. The copper side faces up.

 

 

Before installation, there was some cleaning to be done of the cylinder block face and piston crowns.

 

 

I wiped the oily residue off as best I could and then set about attacking it with a drill fitted with wire brush attachment. No great pressure is needed when doing this. Any stubborn bits can be carefully scraped off with a screwdriver. The idea is to get as flat as possible a surface so the gasket seats well and evenly. The rag down the bores is a precaution to stop debris from falling in - cleanliness is godliness and this is precision engineered machinery, after all!

 

 

N.B. when the head was away being re-conditioned, I sprayed all the bores liberally with WD40, then took some clean rags and stuffed them tight in. This is to prevent, as best one can, the corrosion of the bores, which is harmful even at a microscopic level.

Here I am checking the ridge at the top of the bore to judge wear. This occurs naturally as the top piston ring does not come up right to the top of the bore, thus a ridge is eventually made over many miles. These bores are in good enough condition for an old engine with some 60,000 miles.

 

 

 

It is worth noting that, when an engine starts smoking and using oil, a re-bore is not always necessary as the piston rings wear out first. On an engine I did in the past, the bores were honed after expert opinion and I fitted new Cords 'ridge dodger' piston rings to great success. Without going off on too much of a tangent, this is why cold-starting and short journeys are bad for an engine, as the rich petrol mixture washes out the oil from the bores, resulting in excessive friction. So starting up the engine just for a few moments then switching off is definitely bad for an engine.

 

Now, a common problem when removing the cylinder head nuts is that, over time, they seize to the stud, and quite often the stud itself will unscrew from the engine block. This happened to me, so I put some rag around the stud to protect it against damage from the vice teeth. Then, with the vice tightened up, the nut can easily be worked loose and the threads cleaned up.

 

 

To be continued...

[mercrocker]

Good going there so far! Head cost seems quite reasonable, certainly cheaper than an exchange unit which I never feel happy about - much rather the same head went back on a serviceable engine.

[Honey Badger]

Great Thread.

 

I have pleasant unpleasant memories of helping my mate swap out his 998cc lump for a 1275cc Metro unit in the mid 90s, using scaffold poles, blue BT chord and brute strength the lift the engine out, it's still in the coalplace at my old flat as far as i know, might be a bit* rusty now.

 

I'm reading this lying down after back injections last week, I'm sure* that it isn't linked to changing the A series.

[steve_earwig]

175 quid doesn't sound too bad at all.

 

Me and a mate rebuilt the engine on his Riley Kestrel (calm down, it was an Austin 1100 with a grille) about 25 years ago, stepped piston rings on that too. I only have vague memories of that, mainly that it is possible to drop the distributor drive down into the gearbox (the cam gears are helical so you have to drop it in slightly turned, I wasn't happy how it looked so, hold on, I'll just redo that, clink, clank rattle... Magnet on a stick saved the day there). The other one was his brother decided to do the valve on the engine hoist up really tight so it was a bastard to undo, when I did manage to crack it off it all came in the rush, engine/gearbox heading for the concrete floor at a high rate of knots but I just managed to stop it with a couple of inches to spare.

[Dave_Q]

Good action so far Squire and agree the head work sounds reasonably priced.

 

Just a point on prepping the block, is a wire brush type thing the best thing for it? Appreciate you will be being extremely careful but the block needs to be as flat as possible for best sealing.

 

In the past I have used a block of metal like this wrapped in a sheet of wet'n'dry.

 

Happy to be corrected if that's not best practise, just my 2p.

[Guest Lord Sward]

Is it not worth doing a wet test on the bores, i.e. pouring some paraffin in to check the balance of the drain-down.  Note; I'm not a technician. 

[Squire_Dawson]

Thanks guys. Progress is steady. Always best not to have any deadline for these things.

 

 

 

Just a point on prepping the block, is a wire brush type thing the best thing for it? Appreciate you will be being extremely careful but the block needs to be as flat as possible for best sealing.

 

In the past I have used a block of metal like this wrapped in a sheet of wet'n'dry.

 

Happy to be corrected if that's not best practise, just my 2p.

 

On an old iron lump like this it doesn't matter as long as there are no gouges taken out. The gasket, when torqued down, will seal things up. I'm not sure about a more expensive engine of different metal, mind you. On tough old crap like this it's ok.

 

Is it not worth doing a wet test on the bores, i.e. pouring some paraffin in to check the balance of the drain-down.  Note; I'm not a technician. 

 

A compression test will tell us more and the results can be checked against the figures in the workshop manual. Either way, it's academic because I'm not touching the bottom-end, this will either work or not when it is eventually started up. It appeared well-maintained so it's reasonable to believe the piston rings aren't excessively worn.

[seth]

Good progress! I've always used a paint scraper to get the old crud off blocks/heads. Just have to be careful to make sure to keep it moving in the right direction and not put a deep scratch in if it were to slip sideways. Means you can control where the waste goes too and avoid getting any down places you don't want it. With the exposed bores wiped clean I then turn it over slowly and allow the pistons to bring up anything I've missed and deposit it at the top of the bore, wiping it away each time.

What did you get for your £175 on the head? New valve seats, guides, skim? Did they dismantle and refit valves etc?