2.0L air-cooled engine rebuild?

[blemvanagon]

Hello i'm new to the Vanagon world and aircooled engines in general and wanted to know what you guys thought about my vans motor. I recently bought a 1980 Vanagon 2.0l air-cooled.

previous owner said the engine started spitting oil out of the exhaust pipe on a trip he had taken and had a big loss of power so it was towed home a year ago and left until i picked it up two weeks ago.

I started it up when i got it home and it ran but was very loud and pretty smokey as well but help an idle just fine. i did a compression test and it had low but not out of specification compression on two cylinders.The low cylinders were at 115 and 111psi. the other two were at 145psi. I then did a wet compression test on the low cylinders and the compression shot up to around 150 so i'm thinking piston rings are bad. I removed the engine and am about to start taking it apart. what else do you think i should check as i'm taking it apart and what parts would you recommend to replace along the way? thanks, any kind of info is greatly appreciated!

[Wildthings]

You should post on the Bay Forum as this is essentially the same engine as used in a 1972-79 Bay Window Transporter.

In general head work is what makes and breaks these engines. You will likely need to buy new heads and have them reworked using high quality valves, seats, springs, etc. Fairly minor upgrades in the cam can give considerable payback, but be wary of upgrading the cam very much if you need to pass smog.

[blemvanagon]

ok i will move the post, thank you.

[Zeitgeist 13]

You should post up pics of the engine so we can see if all the obvious cooling bits are intact. That will tell us a lot about what heat cycling the engine experienced just prior to showing symptoms leading to the forced downtime.

I'm also in Oly.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[blemvanagon]

Okay i will add a photo later today when i get off of work.

[blemvanagon]

here are the photos of the engine Before I removed anything. I now have the alternator and clutch assembly removed.

[chompy]

That looks pretty clean! Do you have the crossover fresh air tube that comes from the fan connected to your alternator?

The blue arrows are sort of pointing to it.
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'81 Westfalia Subaru EJ22
Manual Transmission

[Zeitgeist 13]

Yeah, that looks like it's had some love and attention in the past. I assume you're pulling the heads next?
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[blemvanagon]

Yes I do have the air tube I must've taken it off before taking the picture. The the pervious owner said the owner before them took good care of it and know what he was doing I guess. But yes next I want to take the heads off and get them checked out along with the block I'm thinking just take it to a machine shop to have them look at it since I don't have much experience with these engines. Is it difficult to check and replace pistons?

[Zeitgeist 13]

Once you get the heads off, the issues may be obvious. The pistons and cylinders are really easy to service once the heads are off. You could just pull a rod out and see if the bearings are scored or a few lifters out to see if the cam is pitted or flat.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[blemvanagon]

Ok so I removed the head on cylinders 3&4 which had low compression. The head looks ok to me I can't see any cracks and the valves don't seem corroded or anything. Can anyone see anything wrong with it? I also removed the cylinders on 3&4 and the piston has wear marks on the side and the bottom ring looks like it's worn out on both pistons to me because I can see the small spring on the inside. That's just what I think I haven't done the other side yet to compare because I ran out of time but what do you guys think. Bad piston rings?

[williamM]

Those seized at one time from excessive heat- See if your thermostate and flaps are present- Saw one where the flaps had been removed and that 3/4 side looked like that. So did the motor in the Grey whale have identical scuff marks.

Your not going to be able to reuse those pistons- so might as well do both sides.

Those heads were leaking pretty bad also. If you plan on keeping your motor any length of time- you might consider some AMC rebuilds . General consensus here is the new AMC's will run as long as 30,000 miles- where as if you put quality valves/guides and springs on them they hold up pretty well- I get every used AMC head I see. and then re do them.

Agree with checking rod bearings - especially the ones scuffed so badly.
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some days I get up and just sit and think. Some days I just sit.

opinion untempered by fact is ignorance.

Don't step in any!

[chompy]

What do the cylinder walls look like? I'd personally grab a new set of pistons, rings and cylinders since it looks like this thing was leaking/burning oil pretty bad anyways. If the head is ok and not cracked you could just fill the chamber up with fluid and see if it leaks by blowing air from the opposite side. You'll see bubbles start to form around the valves if they aren't seating well. There are other ways to do it as well.... might be worth it to bring the heads into a machine shop so they can check if its warped and can properly check the heads out. Not sure how much you want to spend.
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'81 Westfalia Subaru EJ22
Manual Transmission