2001 C70 VVT Big Oil Leak ?

[cuhfs]

2 Questions - I have a big leak on the passenger side all over the timing belt area. Leak appears to be from the exhaust side cam which is a VVT hub. I removed the timing belt and removed the VVT hub and as you can see the cam seal appears to be fine.

1.) Is it safe to assume that if the cam seals looks fine see picture... and is in place; that the leak was the VVT hub and not the cam seal? I could not see the leak to be sure. I rather not do the cam seal if it ain't broke.

2.) see picture - the driver side intake cam had a plastic cap and once removed a little oil came out. It does not have a cam seal! Is that normal?

Thanks

[FlyingVolvo]

A few months back I had a big oil leak from exactly that area. Fine oil mist coming out of timing belt area cover. Are those seals original? I'd replace them if you have it open anyway. Personally, I'm not too familiar with the details on these engines, but I don't think there's a lot of other places for oil to come out on the front side of the engine like that.

[cn90]

I discussed this with another fellow with XC90 2.5 VVT in the thread below.
We made some diagrams so you can see the cutaway view of the different seals in the VVT unit.

Basically:
- External Leak happens when the Cam seal leaks (If that is the case, buy Volvo or Corteco Only).
Trick on how to install the seal using PVC etc. is in my timing belt thread.
- Internal leak if O-ring leaks (oil simply flows back to the engine). If this is the case, some have success with new O-ring (difficult to finbd). Many just buy a new VVT Sprocket, which is about $250, which is not bad considering the VVT lasts some 170K or so.

MAKE SURE you check the photo by jordank.

http://volvoforums.com/forum/volvo-xc90 ... 251/page2/


PS: The VVT setting during installation. Ignore VIDA, it is basically useless.
- Follow the 1.5 cogs, 2 cogs thingy (i.e. VVT sprocket marks 1.5-2 cogs CCW of the mark on the cover).
- Once the Torx bolts are tightened (cam locking tool still in place), the VVT sprocket should be about 1.5-2 cogs to the LEFT of the mark.
- Now turn the sprockets CW until it stops, as long as the marks on the sprockets line up with the cover when you turn it all the way CW (by hand), then you are OK.
- If you have ever fixed BMW VANOS, then the Volvo VVT thingy is very easy.

[Klausc]

The hard part is removing and replacing the VVT and sprocket. Replace both cam seals as the intake is also leaking. The exhaust cam "looks" clean but is likely washed with oil, get OE replacements.

[rspi]

[rspi]

Yes the intake cam rear position does not have a normal cam seal, the cap seals it fine.

[cn90]

The Front Exhaust Cam Seal: sure it can look good but look means nothing when it comes to leak.
Leak happens when the seal hardens with time/mileage and is no longer pliable and performs sealing function.

The Rear Plastic Cap is the only thing that stops the oil leak. Yes, get new caps.

[bmdubya1198]

It is possible the VVT hub itself is leaking oil, as it is oil filled. The T50 cap on that hub has an o-ring on it, and it may be leaking. Otherwise, if you have the hub off already, I would do the seal just for peace of mind.
+1 to this being easier than BMW VANOS. These cars actually have a pretty simple VVT setup... I was confused by it when it was a problem on my cousin's car, but that just made me learn it. Make sure once the cam gear/VVT hub is tightened down, you turn it clockwise to its limit and the alignment mark on the gear lands on the mark on the TB cover.
As rspi and cn90 have already said, that cap is in place of a rear cam seal on these '99+ engines. No need to worry about it unless it's leaking. If the cap is damaged, replace it. $11 part at the dealer, and I think NAPA even sells them for $3.

[cuhfs]

Hi, I removed the o-ring from the VVT with a scrib as Robert DIY shows.

2 questions:

1.) The o-ring came out without any problem and it looks fine (flexible..). Not brittle, not out of shape. Could the leak still be the o-ring???

2.) The Cam seal looks perfect too. Hoping one of these items are the leak but it is hard to tell which could be the problem.
How do I know if these are the true source of the leak or Any thoughts as to if the leak source really is the o-ring versus the VVT hub itself being worn?

[MadeInJapan]

cuhfs- you've got it that far...best not to guess on this stuff. Seals don't cost that much. Just replace it for peace of mind. You don't want to do this job again!! Oh, and in respi's video the o-ring still looked fine but he replaced it. AGain, best so you don't have to make guesses like you're doing now!!