Oil Leak '99 V70 - Large, but Hard to Find Topic is solved

[nickelghandi]

Hello all and happy St. Patrick's Day,

I am working on my 1999 V70 GLT AWD (2WD converted before my ownership), and I am chasing an oil leak. See the list of replaced/refreshed parts at the bottom of the post.

I have recently replaced the cylinder head with one that I purchased and had rebuilt. I have zero boost, which I have isolated to the Boost Control Solenoid or TCV, however you want to say it. Some extensive testing revealed that it is stuck blowing the waste gate actuator open under any sort of boost. I have a new one on order and if that doesn't work then I will begin troubleshooting electrical things for that, but for now the major issue is the smelly (burning on contact with hot exhaust pipe), messy (puddle of oil - about 1 qt/100 miles), oil leak that I cannot find to save my life.

The main purpose for this post is I am chasing a mystery oil leak. During the R&R on the cylinder head, I replaced the turbo oil feed and drain lines and gaskets. I also redid all of the cam seals while it was apart. It leaked before the head job, and is still leaking now. Just today, I tore it back apart down to the rear exhaust cam seal and replaced it again just in case. There was a tiny leak, but now it is bone dry after the replacement, and there is still oil dripping from the bottom of the vehicle. The oil appears to leak from that side because if I chase the drips back up the engine, it goes up to the bottom of the turbo, and basically stops. There is a tiny bit of residue on the PTC intake inlet, but that doesn't look fresh.

I can only get it to leak while under load, and when parking after driving, there will be a small puddle underneath. I can let it idle all day and it will never leak. At this point I am beginning to suspect the rear main seal, but the leak seems to be higher than that. I will try to get some pictures up soon, but right now they would just show oil everywhere on the back and bottom of the engine. I just de-greased today and will be trying to trace the leak a bit better tomorrow.

Things replaced during cylinder head R&R:
PCV - all hoses. Kept breather box and cleaned thoroughly.
Vacuum lines - Any that were in the way and any that looked rotted.
Timing belt kit - Water pump, timing belt, idler pulley, etc, etc, all parts to do when doing a head job.
All cam seals
All seals within and surrounding the cylinder head
Turbo oil feed and drain lines and gaskets

TLDR: The leak only happens under load and is almost certainly not cam seals or RMS. Could be Turbo oil feed lines, or o-rings to block from feed lines, but cannot confirm. There is a visible drop on the bottom of the turbo housing, but there are visible drops almost everywhere...

Any ideas???

[tardcart]

you are not getting vacuum to the breather box. I think your model has a diaphragm control on the box. they go bad or check lines to it.
not sure if you have a PTC oriface on the turbo fresh air pipe, but check to see if clogged. If its not that then turbo could have bad seal.
but that would cause cloud of white smoke on the hi way when you pass, so doubtful.

[RickHaleParker]

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Tracer dye.
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[precopster]

Turbo drain pipe at union on rear of block can leak a ton of oil under load...the other end without a gasket.

Is it also flinging oil onto the RHS drive shaft?

[nickelghandi]

Rick, Tried the dye and it was of no use. The oil is going everywhere on the back of the engine and so is the dye.

precopster, I am thinking maybe turbo drain pipe at the block or similar. It is an AWD model so it is pretty difficult to see up in there.

Now I am getting a P0014 error, so I am thinking I am losing a bit of oil pressure causing the VVT solenoid to act up. I am only taking it on test drives at the moment and not relying on it, so I have time to chase this. It really puts out oil under load. It leaves a good sized puddle under the car. It isn't getting worse, but isn't getting better either. I have replaced the rear exhaust cam seal, and the oil dipstick seal now because they both had small leaks, but I am still having this large leak somewhere on the rear.

In other news, the new TCV fixed the lack of boost so it doesn't feel like a snail anymore.

[precopster]

That would be the most difficult pipe to access with an AWD. I was thinking this when mine failed when I put the motor together 3 years ago. I ended up buying a new pipe as the old one had been disturbed by constant re-insertion and trying to line up the gasket on the other end.

Darn expensive little sucker locally ($157 if I recall correctly)

[nickelghandi]

Well that was a pita to replace... Holy ****... My hands and arm have never been so cut up or grease caked. Gloves? Forget about it.. Thin blue nitrile tore after 5 minutes and anything thicker won't give you clearance to remove or replace things. I got tired of removing pieces of glove so opted for no gloves. So much oil got everywhere. I destroyed one gasket trying to get it in there and finally gave up and let my indie do the job on his lift. No more puddles when I park or smoking from the exhaust pipe.

Just looked underneath my 98 S70 GLT and it looks like it's leaking just a tiny bit too. It's easy to see and reach though. Shouldn't be as much of a problem.

[abscate]

I wonder if this the cause of my wet eng8ne on my T5

After a wash off, no oil visible. No oil at idle. Hot run, wet back of engine.

Uses one liter per 2000 miles

[abscate]

Update,i did the deed and replaced the drain line. Will see if it cures oil leak problem.

I did have my indie look for leaks to no avail a couple years back, looks like this one needed Volvo knowledge.

[precopster]

Glad it worked out. That little guy is hard enough to reach on a FWD. I used Hylomar blue sealant to ensure it stays put. No leaks in 3 years apart from the VVT exhaust cam seal weep.