1988 760 turbo blown cam seal, breather q's...

TylerW71 · Post by **TylerW71** » 25 Jul 2015, 20:29

Hey guys:

A week ago I picked up an '88 760 turbo wagon in good condition. It sat for the last year and I have no service records with it.

When I first looked at it I noticed the engine was covered in oil. After getting it home and running, there was a good-sized oil leak from behind the timing cover.Yep, the cam seal was popped loose.

So, I've ordered and received a new Volvo breather box and took everything off to clean and reassemble. Here's where I guess I haven't seen a good explanation:

The breather box I removed looked old and was a Volvo part, but still passed air if I blew through it. The line to the air intake tube was slightly crusty but not plugged. Same went for the white elbow and z-tube.

The only thing that did look questionable was the vacuum line leading to the intake plenum. It was oily and fit loosely on the intake port, but not split.

The engine seems to run good and doing the oil cap test before working on everything seemed inconclusive. It's not been modified and has about 175K. The only ominous thing I did see was some oil in the intercooler tubes, and the PO said it occasionally put out a big puff of smoke and rattled briefly.

So, can those breather boxes get caked up enough to affect pcv operation but still pass air? Is there anything else specific to an FT engine I need to check/clean/replace while I'm in there doing that other stuff? I have new elring seals to go back in and I'd like to either not have another one pop or at least know I have an issue beforehand. Thanks.

lummert · Post by **lummert** » 26 Jul 2015, 09:27

If the cam seal had previously been replaced with an Elring seal that was the problem. Your best bet is to replace with a Volvo seal. The elring seal fits too loosely in the head. Replacing the breather box is a good idea. It's possible to replace the breather box without removing the intake manifold.

93Regina · Post by **93Regina** » 26 Jul 2015, 11:54

lummert wrote:It's possible to replace the breather box without removing the intake manifold.

For any older vehicle, its best to remove intake and injectors and refit with new intake gasket and new injector o-rings, and while doing it, clean up intake, throttle plate, hoses etc.

Taking short cuts tend to come back "in your face."

TylerW71 · Post by **TylerW71** » 04 Aug 2015, 19:45

Well, to wrap this up, I pulled everything apart and found that the cam seal was an elring, which fit way too loosely. I replaced the 3 seals, glued them with 3M yellow snot and everything is leak free now.

I found about 2/3 of a quart of oil in the intercooler when I drained it, so that evidently explained the random pinging and blue smoke, because the turbo gives no symptoms of wearing.