1998 V70XC - Oil Leak Puzzle

[erikv11]

...
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

OK yeah given that I'd wait on the return line - clean it up and see if it's leaking.

[VolvoOwl98]

Small update while I wait for responses in reference to troubleshooting a no-start after new fuel pump (thread: viewtopic.php?t=108158)

Oil on top of the head again… could be from oil cap (replaced that nearly a year ago, then upgraded viton seal from IPD a few months later to fix the seal leaking), or it could be the PCV hose up there…

Having a car behave like a hydra isn’t exactly ideal… cut off one problem, two more shall take its place

[abscate]

Technically, that’s a Medusa but hydra is approved here, too.

[VolvoOwl98]

Technically, that’s a Medusa but hydra is approved here, too.

If there had been a good enough Swedish mythology equivalent (regenerating heads) then that would have been my first pick... but neither Jörmungandr, Níðhöggr, or Lindorm fit the bill quite right

(Yes that led me down a rabbit hole researching Swedish mythology)

[scot850]

That may be part of your oil leak down the back of the engine. That PCV pipe to the head can get hard and crack or leak where it attaches to the head, but I would suggest it may be from the oil cap as there is oil in the groove below the cap which is the highest point.

No it could be the pipe leaking, but I can recall if you did the glove test on the oil fill hole to check for crankcase pressure?

Being a 98, I think it still has the flame trap in the PCV pipe to the intake hose. If it does that could be blocked causing the pressure to the head and potentially to your cam and crank seals and any other potential weak spots for oil to leak from. Or the oil return lines int the block on the front of the engine from the oil catch tank could be blocked.

Neil.

[abscate]

Oil cap leakage. You can see it up high on the ridge of the tower oil usually doesn’t climb uphill neatly unless it sprays and that’s messy.

You could just quote that Swedish mythological character, this is a low IQ forum of knuckle draggers and we wouldn’t know the difference

[VolvoOwl98]

No it could be the pipe leaking, but I can recall if you did the glove test on the oil fill hole to check for crankcase pressure?

I did check, and there was some slight inflation, with a bit more noticeable when giving it small revs with the throttle cable.

Being a 98, I think it still has the flame trap in the PCV pipe to the intake hose. If it does that could be blocked causing the pressure to the head and potentially to your cam and crank seals and any other potential weak spots for oil to leak from. Or the oil return lines int the block on the front of the engine from the oil catch tank could be blocked.

It does have that hose, and the connector to the intake pipe right by the turbo via the PTC has some oil buildup on it. The other day while perusing around I came across the discussion of using a larger diameter heater hosing for the line running from the oil trap to the PTC to help manage the higher pressure these engines can make as they get older, and will likely do that once live gets a bit less busy here in a few weeks.

Oil cap leakage. You can see it up high on the ridge of the tower oil usually doesn’t climb uphill neatly unless it sprays and that’s messy.

What would the suggestion be here, replace with a new oil cap? It could be caused by the PCV pressure, but the pressure isn't terribly dramatic (not like when I first bought Saskia, thank goodness). I hope it isn't the seal's fault with it being upgraded to viton.

[abscate]

Double gasket maybe?

[scot850]

The caps have 'catch's' or flanges that are what lock them in place can bend with age or wear allowing more of a gap with the seal in place. I have found a variation in thicknesses of seals supplied from different suppliers, as well as the materials not holding up. I replaced one on a friends P2 about a year ago and it is leaking already. Not a Volvo one, but a cheap one from IPD or FCP. It was tight when fitted but had flattened out a lot from a new one even in that time line.

Neil.

[abscate]

There was a thread where someone rammed stiff Pcv tube into the block hole and packed it full of carbon gunk, then cut that piece of tube off , rinse, repeat. This cleared the draft hole without dropping the pan.

Once you get it partly open, bottle cleaning wire brush and routing to get it clean.

Maybe Mike alder from Australia wrote that up? It was someone famous