Club 80-90 Forums

hi all,

watch this forum almost every night and must admit i have learnt a helluva lot from you vw meisters on here but i have a couple of questions to ask which i'm hoping will aid me with the rebuild i'm currently carrying out on an engine at the moment.
having stripped down the engine last night down to the crankcase i have discovered that what looks like an oil scraper ring on one cylinder is broken as a piece of it fell out when i removed no.3 cylinder .so what i'd like to know is could this have caused the engine to sieze? as before it was stripped it was locked solid and now its free to rotate.also some of the pistons have a slight coking down the skirts in the area of the gudgeon pins, is this caused by blow past i.e worn rings or ovalled barrels? if it is would i get away with just replacing the rings and geting the barrels honed or would it need new barrels and pisons etc.? the next question is , i have some sideward movement on the conrods where thy are attached to the crank but no upward /downward movement i seem to remember this is okay but it a long time since i stripped anything down this far and have never stripped down a vw engine.another couple of questions (sorry for being a menace) do you think that the amount of fuel in the engine oil could have been caused by the broken scraper ring? also the airfilter box had about half a pint of engine oil in it when i removed it any ideas on this one?? and the last one (promise) can you re use the small rings that i would cause base gaskets at the bottom of the cylinders or do they need to be renewed?( not trying to be a cheap skate just want to do it properly) and what is the correct name for them?
sorry for all the questions but i have no history of this engine and it seems a bit wierd to me (apart from the broken ring)the symtoms that is as the pistons look quite new as do the heads and all the valves look good too. also when i first rescued the van from a scrapyard it did turn over albiet slowly for about 10 seconds before i just got the dreaded clunk, at first i thought i was just a flat battery or a lasy starter but after charging it i still only got the clunk.

any help here even if its only suggestions would be massivley apprieciated as i have to get it repaired before the summer as i'm going on a ''holiday in september for 6 or 7 months to sunnier climes''and dont want to leave it on the drive way for such a long spell. alseo i'm very curoius as too how the airbox filled up with engine oil and the crankcase with petrol engine is a 1980 2,0 cu Aircooled

thanks all looking forward to your replies

Hello,

I'll help you out if I can.

Firstly, you will want to renew all your piston rings, as a complete set.

Just get a standard set, nothing fancy.

Look very carefully at the 'land' (the groove) that the broken ring was in.
Is there any sign of damage to the piston.

Check this with an equivalent ring off another piston.

Its just that if you have to change a piston, you have to get a set of 4 'cos they are weight matched.

When you refit the piston into the barrel you will have to use a shim type ring compresser, (not dear).

Make sure that you stagger the ring ends, (like a mercedes badge) Use plenty of oil.

You should not have to force the cylinder on, a nudge with the palm of your hand should do.

You will need a gasket set, which will contain the paper rings for the base of the cylinders. Buy a german set, a bit dearer, but soooo much better than cheapo mexican, ( nothing to do with Top Gear)

Let me know how you get on,

Cordialement,

The oil in the air-box is a result of the crankcase getting pressurised because of the broken ring (& maybe scored barrel). This lets blow-by gases get past and blow oil out the crankcase breather into the air-box. If the cylinder with the broken ring let the plug get oiled up and stop firing then the unburnt petrol could have got into the crankcase.

hi sarran and BOXY,

thanks very much for the speedy reply. i understand now what yoou mean about the crankcase compression caused by the blow by.never seen it before on a conventional engine though (find these old vw engines a bit wierd but i'm sure i'll get used to them ha ha ). and yes sarran i will keep you informed about my progress. i watched your video link the other week and have been following your thread on your rebuild on here with great interest as i knew i would have to make a start on mine as soon as the snow melted and it got warm enough. i have a garage but have another car in it at the moment so tryig to do it at the moment is a bit of a struggle as i have very little space and as you can probably imagine every thing is covered in oil and rust all the tin ware needs completely strippingback ,the rust removing and repriming then repainting after rust treatment with a product sold here in germany called fertan (supposed to be very good according to all my german friends who restore old cars).i also have another CU engine which is a runner but the heatexchangers are shot and the tinware is almost nonexistant due to corrosion.it came from the UK and i think it has spent time by the seaside so my plan at the moment is to take the parts required from the broken engine,i.e heat exchangers exhaust most of the tinware heater pods etc. fit them to the good engine and give a good service ,belts oil plugs leads filters dizzy cap rotor arm and rebuild carbs and new front crankshaft oil seal. i will also remove the clutch and check that and if it looks as though its seen better days then replace that too. oh also pushrod tubes as they are a bit corroded and the o rings look a bit tired.would you recommend renewing the oil pump as i have read that its worth doing when rebuilding the engine?
another quick question is does anyone recommend a supplier where i can source all these parts as most of the one i look at will suppliy one part but not others .what i mean is is there one good supplier of Aircooled parts that supplies good quality spares and has quite a comprehensive range? i dont mind paying for quality parts as i want to do this once only as the tinware jigsaw has been driving me mad and also very busy in work at the moment so getting home at about 6 and then not getting out of the garage till 11 or 12 at night .i'll also try and get mrs melmelody to try and upload some photos when we figure out how to do it so you can see my progress and the state of my garage thanks again for the replies speak soon .

mel.

Hello,

For tinware, I degrease in a paraffin (kerosene) bucket. (soak for 24 hrs), then brush clean and use white spirit or similar to finish. Dry, (preferably with compressed air), and then wire brush off all the rust.

I paint directly with Hammerite hammer finish enamel, 2 coats within 24 hrs.

This kills rust and is pretty much dirt proof.

We will maybe be filming this procedure this week end.

As for parts, in France I use Serial Kombi.

Cordialement,