My exhaust cam doesn't have a timing mark (and I think I'm off a tooth)

[ziper1221]

I have really no idea how this happened. I finally got around to doing the timing belt on my 2006 V70 2.5T with 240k miles. I marked the cam sprockets and crank pulley, and aligned the new belt with the painted marks. I rotated it by hand with no issues. I checked everything by lining it up with the factory marks, at which point I realized the exhaust came does not have a timing mark. When I line up the intake cam mark, the crank mark seems to be off by one tooth. The car runs reasonably well. I read online that the VVT has 1 to 2 teeth worth of adjustment in it. I wonder if the previous mechanic put in a replacement unmarked cam or what the hell happened, but now I just want to try and figure out how to do it right.

I've got a ton of oil leaks and most likely a clogged PCV. Should I buy the cam locking tool, pull the cam sprockets, change the seals, and reset the VVT from scratch?

[chrism]

Are those your yellow paint marks or a prior mechanic. I suspect the exhaust sprocket has been separated from the hub at one time or another. Look all the way around it and see it was remounted 120 degrees off one way or the other.

[cn90]

The cam marks are there.

The oil leak is from excessive play in Exhaust VVT Hub.

Anyway, I wrote a DIY VVT Hub/Cam Seals for the 2007 S60 in this forum.
You may want to take a look at it.

At that mileage, you will likely need a new Exhaust VVT Hub...
Or install the exhaust cam seal in reverse...

[ziper1221]

Are those your yellow paint marks or a prior mechanic. I suspect the exhaust sprocket has been separated from the hub at one time or another. Look all the way around it and see it was remounted 120 degrees off one way or the other.

Indeed, the yellow paint was already there.

The cam marks are there.

Really? Could you circle it?

[cn90]

Assuming the photos were taken at the same time, then the previous mechanic moved the marks, He might have replaced the cam seals before and reinstalled the VVT Hub differently. Not a big deal as long as the hub is in the most CW position (once the T55 bolt is torqued down), and the rear of the cam shafts were locked with the tool...

Anyway, here is the 2007 S60 VVT Hub DIY:

viewtopic.php?t=100439

[abscate]

If it is off time it will code the ECM-644 ? can pop the Check engine light on after the first restart, so if you dont have that, its timed right. The marks are there but they are really small and easily missed.

That Dayco timing belt is not known for its consistency vs the Conti Tech belts, its worth checking the other parts of the TB system for criticality.

My guess is the VVT exhaust hub was reinstalled off marks. Annoying.

[ziper1221]

If it is off time it will code the ECM-644 ? can pop the Check engine light on after the first restart, so if you dont have that, its timed right. The marks are there but they are really small and easily missed.

That Dayco timing belt is not known for its consistency vs the Conti Tech belts, its worth checking the other parts of the TB system for criticality.

My guess is the VVT exhaust hub was reinstalled off marks. Annoying.

I had code ECM-671D, but I think it might've been spurious, since I haven't gotten any more codes since clearing them a couple hours ago. No other codes relating to timing. Think I should just not worry about it then, since 1 tooth would give an immediate code?

I don't understand your comment about checking the other parts of the TB -- I put in the new dayco belt, idler, and tensioner just now.

thank you

[cn90]

Could you line up the crank and cams to the marks, then post photos of all 3 areas...
- Crank
- Exhaust Sprocket
- Intake Sprocket

[scot850]

It may be just me, but in the 2nd photo of the exhaust cam, as cn90 suggested, I think I see the cam marker near the next bolt CW. So possibly fitted 120 degrees out.

Neil