73 Camper suddenly losing & burning oil

Hello, everyone - I'm the defacto caregiver for a pretty old 73 poptop camper. While the body is nearly perfect, we've replaced about 2/3 of the mechanical pieces. I've used the archives of this group extensively for information about symptoms I'm seeing, but I'm a little stumped now and am wondering if anyone can help...

The engine that's in there now is fairly new - not more that 5000 miles, according to the 3000 that were on it when it was sold to us, and the 2000 we've put on it since. More recently, I've replaced the starter and alternator, rebuilt the carburator (solex 2 barrel), tuned it up, etc. It was running pretty darn good for at least a week there.

We took the van to the eastern Washington desert this weekend. At one point we got onto some very dusty roads, which clogged the air filter and, eventually, the points. At this time I noticed a slight oil leak starting; I thought it was the right valve cover.

Once we got the points and air cleaner cleaned up, it ran famously again. But as we headed home it began eating more and more oil - like, a quart every 60 miles or so, now. I just replaced the points (they had gotten sorta fouled) and that helped it run a little smoother but it's still losing oil and, now, burning a lot - a good screen of smoke, especially on startup.

The oil is most prevalent around the oil filler and dipstick, and it's leaking along the left-to-right seam in the engine block above the fan (I'm not sure what that area is called). From what I have seen, that says a leak around the pulley - and two mechanics have said "rear seal" and "pulley seal" - but from reading this group, it sounds like there's no seal there, and I'm not sure how to address that problem. Would a leak there cause oily exhaust?

The oil leaks while it's running, and a considerable amount just after stopping. But not to much when it's idling, and none when it's not running...

Further - I checked the PCV hose, it's clear and there's a lot of smoke coming out of there. When I connect it to the air cleaner, the engine slows 100-200 rpm.

Can anyone help me here? What more can I check out? Is this indicative of a leaky pulley? How can I check that?

Thanks in advance! Elijah

Reply to
Elijah Smith
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There is no left to right seam in the case itself, so I suspect that you're talking about the seam in the fan housing. If you're getting oil thrown out there then my guess is that it is indeed the rear main seal. In a 73 bus you have a type 4 engine which DOES have a rear main seal. Pully seal would not be quite the right term, but the people who used that term mean the same thing.

Fortunately, the engine does not have to come apart to get to this seal, but there is still a fair amount of stuff that has to come off. I think this work could be done with the engine in place, but there are some special tools required to remove the fan.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Reply to
Jim Adney

Jim - thank you! It's a relief to hear you say there is a seal there

- I thought I was getting jerked around by the mechanics I had talked to... or slowly losing my mind...

Now that I reread old posts, I see a few references to the fact that there is a rear main seal in type 4s. Have you replaced them, engine in? Any hints? is it pretty straightforward? Could I get the pulley off with a standard puller? I have two pullers, different sizes...

Also - would a blown seal cause significant smoke in the exhaust? I can't quite see how it would, but would love to hear that fixing the seal might stop the smoke. They definately started at the same time.

Thanks for your help, sir! I really appreciate it.

Elijah

Reply to
Elijah Smith

Jim - thank you! I had seen so many references to there NOT being a rear main seal in the aircooleds, I thought I was being lied to, or going insane...

Can you give me any pointers on replacing the seal? I have a couple of different gear pullers - will they work? Have you done the procedure? I couldn't find it in the Muir book and haven't looked deeply into the others yet...

Also - any chance the blown seal could be causing the smokey exhaust? I can't figure out why it would, but the smoke started when the leak did, and I really would like to think I'll fix them at the same time too.

Thanks again! I've been rereading the archives with this new information; I see you contributing useful tidbits and opinion over and over again. I appreciate it!

Elijah

Reply to
Elijah Smith

sorry for the double post - first one gave an error, had to rewrite...

Reply to
Elijah Smith

You should have a Bentley manual if you're considering doing this. It will show you all the steps. I've never done it. I don't do much work on type 4 engines.

Once the oil is in the fan housing the next stop is to blow it into the heat exchangers. If that's what you have I would expect your bus to fill up with smoke as soon as you turn on the heater. Oil inside the heat exchangers would generate a lot of smoke.

Of course your heater may not be connected.

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----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Reply to
Jim Adney

Oh, sigh, sad. Long day under the car (did some brake work while I was there) to find a clean, dry rear seal. I changed it anyway, still leaks.

Because of the excessive blowby coming from the PCV box, and because I just discovered the #1 piston doesn't seem to be firing (no change when I pull it's spark wire), I'm now thinking maybe those rings burned, the crankcase is overpressurized, and oil's coming out the fill & dipstick tubes at high rpms, getting pulled into the fan from there...

:(

btw, my small puller worked famously on the pulley hub.

thanks for the help!

elijah

Reply to
Elijah Smith

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