Oil leak from camshaft front seal

[940volvoman]

Has anyone had to replace the front oil seal on a 940 camshaft?I think mine is leaking quite a bit.I haven't yet removed the timing belt cover to inspect...

[360beast]

Yes I've done loads.

Do you need some advice?

I would start by removing your PCV box and giving it a thorough clean out or replacing it (still available from Volvo and aftermarket suppliers). If you haven't done it before then it's probably causing excessive crank case pressure which causes oil to blow out of the seals.

[940volvoman]

Hello,360 Beast.Yes, please,I need some advice.

I have often wondered about the PCV and cleaning it.I came across this problem many years ago on a Fiat 127 which was blocked solid...

Thanks in advance

[J liddy]

Luke is top man on these engines so .he's done some excellent work for me on my 900 !!

[360beast]

Originally Posted by 940volvoman

Hello,360 Beast.Yes, please,I need some advice.

I have often wondered about the PCV and cleaning it.I came across this problem many years ago on a Fiat 127 which was blocked solid...

Thanks in advance

The PCV is located under the inlet manifold, remove the vacuum lines going to it, they should just pull off. Then you will need to unbolt the metal sleeve for the wiring loom that also bolts through the PCV. Then it is one or two bolts that hold the PCV in place, it will lift out and you'll need to wiggle it around to get it out, if you have a 95/early 96 car then you'll probably have EGR junk in the way too which will need removing (preferably blocking off and binning IMO). It's easier to replace it but if you don't want to then bang it in a bench and solid carbon deposits will come out, once very little comes out I would then soak it in some sort of cleaning agent, wether that be degreaser or something else is your choice, my mate soaked his in petrol. Don't forget to replace the o-ring part number 949659 still available from Volvo or parts for Volvo's etc.

To do the crank seal, I would highly recommend doing the auxiliary shaft seal both part number 6842273 and the front crank seal part number 1276425 NLA from Volvo but the skf one appears to be the exact same so I imagine that's where Volvo gets it from. The front crank housing gasket is probably leaking too, I'm yet to see one that isn't and I know others on here say they haven't found this but literally every single one I've done the bolts are loose and the gasket is leaking, the part number is 1276425 available from Volvo but it has to come from GCP in Sweden. The gasket is longer than it needs to be so I cut the excess off and where it exposes the sump gasket once off I use gasket sealer along there to make sure the sump doesn't leak at the front.

You'll need to remove your V belts, if you don't have an impact gun then you'll need the crank locking tool, others have jammed the flywheel but I'd rather not risk damaging the starter ring gear. Then slacken off the Crank pulley bolt (24 or 25mm I can't remember of the top of my head) and then remove the locking tool. Remove the top cover and then spin the engine over so the crank and cam timing marks line up.

Remove the crank bolt fully and then pull the crank pulley off, remove the bottom cover (you'll probably need to pull the waterpump pulley off to remove this) then you will have everything exposed. You will need to remove the cam and aux pulleys now, you can put the crank pulley back on then put the locking tool in place and remove the 15mm bolts from the pulleys, they're usually quite stiff even though they're only done up to 50Nm. Then pull the pulley and locking tool back off, slacken off the 15mm nut for the tensioner then push the tensioner as far left as you can then tighten the nut again to hold it in place. There is a hole to put a pin in but it is usually still difficult with this pin in place so it's better to go past this point.

Now you can pull the belt off and all of the seals will be exposed, clean all the oil and grime off the front of the engine then you can remove the seals and fit new seals to the same depth or even a little bit deeper if there's a groove but make sure you get the lip of the seal the correct way around or it will leak.

The timing belt is part number

Cambelt pre 1993 271713
Cambelt post 1993 3507704

To remove the crank housing there are about six 10mm headed bolts and the oil pressure sensor wiring on the bottom has a nut that holds it on and then the stud has a nut at the base of it which needs to come off too, then there are two 12 or 13mm headed bolts that go through the sump in to the bottom of the housing, it will then need a bit of levering and persuasion to come off. Put a rag in the hole that's left so crud doesn't go in your sump, clean all the old gasket off and then the rest of the information I put at the start of this post.

If you want pictures of it there are some in my project thread

https://www.volvoforums.org.uk/showt...290481&page=15

There might be some in this thread too

https://www.volvoforums.org.uk/showthread.php?t=311775

[Forrest]

Just a couple of things to add to Luke's excellent advice above.

When buying the radial seals try to obtain OEM or at least the same design as OEM. There are two different sorts of radial oil seal which require different approaches to fitting as described here.

https://www.skandix.de/en/news/oil-s...ferences/1374/

The 940 uses type A.

Whilst you can in a pinch knock the new seals into place with an improvised tool, IMHO there is no substitute for the genuine Volvo assembly sleeves.

Petrol and a stiff brush is effective at cleaning the gunk off the front of the engine once all the belts and pulleys are out of the way.

When assessing whether to follow Luke's advice about replacing the timing cover gasket bear in mind that if you do damage the sump seal removing and refitting the sump is a non-trivial task on these cars. The same goes for if you inadvertently displace the PVC oil return tube. So take care and don't force anything.

Good luck!

[940volvoman]

Thanks for your help,there 360 Beast.

It seems like a much bigger job than I expected, but I might break it down a little by trying to inspect /fix the PCV system first...

[360beast]

Originally Posted by 940volvoman

Thanks for your help,there 360 Beast.

It seems like a much bigger job than I expected, but I might break it down a little by trying to inspect /fix the PCV system first...

I'd definitely start with the PCV system.

Honestly it sounds like a lot but even if you have never done it before you could have it done in a day taking it easy if you're mechanically competent. If you're pretty new to doing stuff like this then set a weekend aside for it and make sure you have all the tools and parts ready before starting.

[baggy798]

Ancient Chinese Proverb: Onry fix what is bloken.

[Rversteeg]

Excellent write up of how to get to the oil trap:
https://www.volvoforums.org.uk/showthread.php?t=71672

I did it a few years ago with the help of these instructions and it was quite easy. I do not have EGR which made life a bit easier. On the other hand, I do have an inlet manifold with four additional LPG injectors to make access more difficult. No need to take the manifold completely out, just unbolting it from the head is sufficient.

I removed the oil trap basically to fit a new gasket underneath (original one had hardened) and found the trap itself was still clean, even after 300K+ miles. Thanks to a lot of motorway driving, LPG and good quality oil maybe?