1998 V70XC - Oil Leak Puzzle

[VolvoOwl98]

I discovered a curious oil leak from Saskia today. When putting her up on ramps to check for the source of the oil drops that had landed in the drip pan (with fresh absorbent material), a medium-ish leak started to drip oil. Yet when driving off the ramps and remaining on level ground, the only oil dripping was residual.

At 178K miles and recently did an oil change, which didn’t have the leak even when up on ramps, so it’s a recent development.

It appears there’s two leak locations needing to be identified (my leaking oil pan drain plug I’m aware of and am trying to figure out how to remedy).

Overall view of the mess :(

The first leak seems to be coming from nearby the turbocharger on the left side of the car, and is the dominant one that made itself known when Saskia was on the ramps.

The other looks to be coming from the right by the black fuel and evap lines that go over to the top of the engine, as well as the fuel pressure regulator and other things on the right side of the car. (Also noting that the oil cooler lines attaching to the radiator need new o-rings and clips.)

My main focus is the leak that comes out when on a frontal incline. The other two (drain plug and right side leak) I would also be appreciated having input on.

[scot850]

Drain Plug - Did you replace the crush washer when you did the oil swap? If not, that is likely the reason for the leak.

Back of engine area. If is is definitely engine oil, cheek if the oil filler cap is sealing. The seal ring goes hard, and leaks oil into the top of the engine under the spark plug cover. There is a drain out from there at the back of the head at the RHS when viewed from the top. That same oil can leak out the LHS of the head and down the side of the engine.

Another possibility is your cam seals are leaking. If the car was sitting for a long time it could be the oil seals dried out and are now leaking because the PCV is pressurizing the block and blowing oil out the can or crank seals (both front and back).

Assuming all the leaks are engine oil, then turbo pipes are another leak point.

I would suggest spraying the oil leak areas don with brake fluid cleaner and seeing where the oil is coming from.

Remove the spark plug top cover and see if the oil is leaking from the oil filler cap and is sitting on the top of the engine. If it is, clean it off and replace the oil filler cap seal. Just leave the spark plug cover off until the issue is completed.

The also carry out the PCV glove test. Place a glove over the oil filler with the cap off, start the car and see if the glove inflates, stays flat or gets sucked down. As you have a 98, you can rev the engine from the engine end of the gas pedal cable and see what happens. If the glove inflates then the PCV needs done. PCV blockage will blow oil seals out and can leak from the area of the cat can on the front of the engine and it leaks around the block and down the LHS(from the front) by the crank pulley.

Neil

[VolvoOwl98]

Drain Plug - Did you replace the crush washer when you did the oil swap? If not, that is likely the reason for the leak.

I did, yes. I had to buy a nee drain plug from a local auto parts store as the old one got chewed up when trying to remove it (as detailed in a recent post in the main maintenance thread linked in my signature).

If is is definitely engine oil, cheek if the oil filler cap is sealing. The seal ring goes hard, and leaks oil into the top of the engine under the spark plug cover.

Replaced the seal with the viton seal from IPD to remedy an issue of oil leaking out from the cap when on inclines. It’s not leaking.

There is a drain out from there at the back of the head at the RHS when viewed from the top. That same oil can leak out the LHS of the head and down the side of the engine.

Thanks, I didn’t know about this and will check it out later today.

Another possibility is your cam seals are leaking. If the car was sitting for a long time it could be the oil seals dried out and are now leaking because the PCV is pressurizing the block and blowing oil out the can or crank seals (both front and back).

PCV system was replaced by a local Euro car specialist (used Volvo OEM kit) shortly after I bought the car about 9 months ago. Will do glove test again to verify that’s still working okay. There looks to be a slight bit of oil on the timing belt side of things, but it looks old. I’ll have to see about removing the cover (which is a bit broken already). I’ll also pull the distributor cap and rotor to check that seal, and inspect the other driver’s side seal.

Assuming all the leaks are engine oil, then turbo pipes are another leak point

They all very much seem to be oil. I replaced the return line gasket and o-ring recently and from photos that seems okay. The feed line could be leaking. I do know a bit of oil is present on the air intake side, with a little in the intercooler piping too.

Thanks for this, I’ll take a look at the new stuff today.

[abscate]

That looks like a cam seal exhaust side leak . I don’t think your 1998 xc70 has VVT so that’s an easy fix

The rear of the engine looks like the turbo drain o ring didn’t seat right. I chased that leak for three years

[VolvoOwl98]

Took the cover off and forgot that I hadn’t gotten a chance to clean the oil leakage from when the cap seal first went bad, then forgot about it

Seal on the cap is looking good

I couldn’t find the ‘drain out’ on the head that scot850 mentioned, but I could see the rest of the head was pretty clean.


Onto discoveries… did the glove test, and it did have some slight inflation that increased with small revs. Grr

Also noted a fair bit of oil from the PCV line that connects to the air intake right before the turbo inlet

I also noted that there was oil on the outside of the two tubes that come from the catch can by the intake manifold. Not entirely sure what to make of that, other than that there’s an issue there


Tried to get a view of the catch can, front of the engine under the intake manifold looks okay

After pulling out the air intake pipe and shifting some hoses around, I believe I found the culprit (as I see abscate just mentioned). It does indeed appear to be the exhaust camshaft seal on the driver’s side behind the camshaft position sensor. There was a lot of oil that was on the lower screw and the bracket that helps guide the evap, SAS check valve, and turbo hoses

I remember now when I changed the distributor cap and rotor that there was also a small amount of oil in there, when the time comes to replace seals I think it would make sense and be wise to do both at the same time.


Then a bit of clean-up of the old mess with some shop towels. Hopefully it stays about this clean lol

The rear of the engine looks like the turbo drain o ring didn’t seat right. I chased that leak for three years

That’s good to know. From feel it seemed okay and earlier photos seem to not show too much of a mess, but I’ll get under there a different day and check on that

[Clemens]

+1 on the turbo oil return line seal and the cam seal

[PatternFlyer]

If you have glove test (ballooning) and rear cam seal leaking & PCV job done. Most likely same thing that I have to fix soon based on a local volvo mechanic. Not sure what it is called. It is part of PCV. The oil trap box connect to the engine block. oil from the trap box is draining down from the block to oil pan (square hole) in the attached pictures.

I am still trying to figure out if I should drop the pan and open that blockage or find something to poke through. Not far from out side, but it appears to go down more than a few inches.

There is a youtube video:

I've done the PCV twice without knowing about the blockage. Still have parts that I took out last time and they are all clear without any kind of blockage.

Ihncheol

[erikv11]

I think at this point I'd

1 change both rear cam seals (easy job; use only Corteco brand seals)
2 consider replacing the turbo oil drain return line seal (messy job)
3 accept that the bottom of the turbo will always have a few drops of oil on it
4 clean up the oil messes everywhere, then see where/if they start from anew

[VolvoOwl98]

I stumbled across another thread discussing the oil pan in relation to PCV issues, and apparently there's some sort of screen in the oil pan that can get fouled up. At some point when time and money allows I'll get to dropping the oil pan to replace the seals and clean things out (also have to figure how many of each length of bolt to order to replace the old ones that seem like they're going to be very troublesome).

Rear camshaft seals are something easy I can do and will get to soon, tomorrow I'm going in and replacing the fuel pump with a unit from VAST Tuning (thread here:viewtopic.php?t=107994&start=10).

I don't mind a small bit of oil being on the underside of the turbo, it is admittedly 27 years old and hasn't been rebuilt/serviced to my knowledge.

I'll take a look again at the turbo return line and probably pull it out to spray it with some cleaner to ensure the o-ring on the block side can seat properly. Not the most excited about getting in there again after it taking 6ish hours the first time, but at least I have more of an idea of what I'm doing. May or may not get to that this weekend, really depends on how the fuel pump replacement goes and what my back can handle lol


I probably should have mentioned when first starting this thread but I replace the seal and o-ring on the oil return line a bit back. I have it documented in my main thread about Saskia, but I forgot to carry that info over to here... whoops

[PatternFlyer]

Complete Vast pump or just the internal? Are you going to do the direct power?