V40 and S40 (2004+) owners rejoice! Help and advice is here for you while you’re working on your Volvo’s timing belt.
This is also applicable to 2000s Volvo 5-cylinder cars with VVT… variable valve timing.
MVS member Bruce:
The timing mark on the cam gear is really not important once you pull the gear/hub off the cam. From then on out you’ll make your own mark on the exhaust cam gear for the next timing checks, here’s why: the gear and the hub with the VVT mechanism mount onto the cam with a center bolt, and can spin forever until you torque that center bolt real tight (80NM) but the point is- there is no reference (like a key or flat) between the cam and the hub, and if you do the job the way Volvo designed it to be done, it doesn’t matter. The crux is- you have to lock the cams in their indexed or timed position (preferably after turning crank to set it at TDC, and before you remove the timing belt), and thereafter- it doesn’t matter what position you install the gear in, you can make a new timing mark for your use later- when installing the new belt and checking it after a couple rotations.
First look at the opposite end of the cams (the drivers side in US) after removing the rubber coated plug on the intake, and on the exhaust- removing the cam position sensor cover and the cup inside, and notice both cams have a machined slot cut across the end of the cam, offset from center, one offset above the middle of the cam center, the other below, (because it is a 4cycle engine). These slots should be aligned or following the horizontal seam in the camshaft cover. You should lock each cam in position with a special tool so you keep the cams in proper timing, and back at the front of the engine (passenger side) look down at the crank timing-belt cog and you’ll see the timing marks (2 grooves stamped into the top of 2 adjacent teeth on the inboard corner or edge of the teeth that needs to be aligned so they straddle the mark on the crankcase.
Those 3 alignment actions- locking the intake cam, locking the exhaust cam and aligning the crank to TDC mark, make for a successfully timed engine. There’s a couple steps to take care of when installing the tensioner and belt, rotating the engine a couple turns to be sure no slack existed between gears/cogs to throw off timing, this is when you want to have your new timing marks on the cam gear already re-established, and the intake cam gear bolts set at mid slot.
Further there is a tool in my ebay-purchased Volvo timing tool kit but I don’t use it, a stubby bolt of sorts, that you push through a port in the crankcase at the left / driver (US) side- that fits into a notch in the flywheel locking the crank at TDC. It’s a pain to get to, requires removing starter, etc. so BEFORE I remove the timing belt — I just make sure the crank and cams are turned to the exact position so that the cam locking tool fits right into place, and if you don’t mess with the crank- (unlike the cams the crank doesn’t tend to turn on its own) then everything will remain in factory timed position, with marks on the crank timing belt cog and crankcase lining up.
Lastly — some people insist on pulling the harmonic damper off, I do not, I just remove the last section of plastic timing belt “compartment” cover that lies under the crank cog and behind the damper, with that out of the way I have no trouble to get the new timing belt in there.