Thread: timing issues 300 tdi....oh my god...

assuming you mean the bolts that mount the drive gear to the injector pump and not the ones that mount the tensioner for the AC belt?

Dont touch em yet, if it was timed right before you took the belt of you might just be a tooth out on the pump or the crank.

firstly you need to establish if you are actually locking the crank or just engaging your timing pin onto the edge of the flywheel.

then you need to insert your timing pin into the injector pump.

If you start messing with the pully mounting bolts for the IP you are most likely going to want a DTI, mag base and an adapter to check the plunger lift height at TDC.

you could have also not tensioned the timing belt sufficiently.

hope thats of some help.

Have you searched through the good oil for the threads that are the how tos on doing the timing belt?

Agree with Blknight - although in the few times I've removed injector pumps I've not had to resort to dial test indicators.

Did you use some marker fluid on the old belt and sprocket, transferring the marks to the new belt to help with installation? Copying marks from the old belt to the new belt helps ensure you are not a tooth out when putting the new belt on, assuming the old belt was not a tooth out to begin with. Pity after installing the new belt, but if you had found you could have locked the injector pump and the fly wheel at the same time (and cam aligned to marker) then in theory your timing should be correct - otherwise re-install the belt.

The black metallic thing you can just make out is the injector pump drive hub. Don't play with the big middle bolt.

The injector pump sprocket comes next and is keyed to fit onto the injector pump drive hub.

Finally, fitting over the sprocket comes the keeper plate.

The sprocket and keeper plate are secured to the pump drive hub by three bolts.

The other two holes on the sprocket are for use with a special tool - the two holes are threaded to take keeper bolts associated with the special tool - the two bolts do not punch a hole into the black thing (but can be used to push the pump off the back of the timing case when all other retaining bolts are removed).

It sounds more like:- you are a tooth out on the belt; you may have already tried to remedy this by loosening the keeper plate to get some adjustment (hasn't helped too much); and that you might have to go back to square one, remove belt, lock pump, lock fly, align cam, re-install belt. I seem to recall that the Haynes manual suggests you can loosen the keeper plate when installing the belt, but this is with the fly wheel and pump locked, and cam aligned.

I might add, I once stripped the aluminium thread from one of the belt tensioner bolt holes. Had set the torque wrench correctly and as I tightened up you could tell the resistance was not there, the feel was just not right - the bolt pulled out with not much effort along with all the thread! Treated the de-threaded hole as a 'new bore' and selected a suitable tap for the size.

As an aside, I tried to buy the special sprocket holding tool from an interstate, reputable, and independent LRover workshop. Seems they didn't use the tool when replacing injector pumps. From their experience the sprocket with belt attached doesn't move much, and provided you've not loosened the retainer plate it should all pull back together. I ended up making my own.

With the crank locked at tdc ,the cam gear on the alignment mark and the injector locking pin in place,
I always loosen the 3 injector hub bolts and rotate the pulley clockwise to the limit of the elongated holes, before offering up the new belt.
As you apply torque to the tensioner the injector pulley will rotate slightly anti clockwise.
When the belt is tensioned, I then apply a little pressure to the 22mm nut on the injector pump until the locking pin can slide in/out easily and while holding that position, tighten the 3 bolts.


I rotate the engine by hand 2 full rotations to seat the belt and then repeat the above sequence.




If you don't rotate the pulley clockwise before installing the belt, you can run out of adjustment to set the pump timing correctly and the actual belt tension will be bad, which is what you may have done.


I hope that makes sense.