Cambelt Alignment Issues!

[Toms306]

Hi guys,

You may've seen in chatbox but I replaced the cambelt, waterpump and tensioners today (306 HDi).

After 2 manual turns, the belt is wandering a few mm off the pulleys away from the engine, but the timing holes still line up perfect.

Ruan suggested I remove the tensioner and idler and clean behind them. Unfortunately this hasn't made a difference. Everything was torqued correctly as well.

So any more ideas? As I haven't got a clue what try next. Wish I hadn't bothered tbh lol.

Tom

[powerandtorque]

Usual cause of this that I've seen is something running mis-aligned so that it's not square to the belt and other pulleys. Really doesn't need to be far out at all to make the belt slowly work its way off - I remember someone's 205 doing the same thing after an engine rebuild and that turned out from memory to be that the head had been skimmed on the piss.

Waterpump would be my best guess if you're sure it was OK before hand and all you've done is belt/tensioners/waterpump.

If you haven't yet filled it with coolant and you've still got good access, swap the original bits back on one by one until the problem goes away - bit of a pain, but atleast you'll know what the issue is there.

[Toms306]

Hmm, ok, effort lol.

It was a genuine waterpump though, and torqued to Haynes spec, so should be alright I'd have thought? Unless I've put too much instant gasket on it, but that wouldn't be 'solid' enough to hold the pump out surely?

[R1-Mini]

Did you put the bottom pulley back on while trying to turn over by hand?
If not then that might be the reason why as it helps keep the belt in line
I always put the bottom pulley back on and nip it up

[C2K]

As above, was bottom pulley on?

[darrenjlobb]

As above, is bottom pulley on AND tight?

does the wondering occur on both cam and HP pump?

[Toms306]

Crank pulley wasn't on, I didn't think it had anything to do with the cambelt, thought it was just to pull the aux belt. Will that be the issue?

Wandering on everything tbh, but most on the cam pulley I guess.

[darrenjlobb]

Put the crank pulley on, tighten bolt, turn engine by hand twice, problem will be fixed.

Cheers n gone

p.s the crank pulley and bolt is what holds the lower belt pulley in against the block / belt on.

[Toms306]

Ahhhhh shit.

Spent hours trying to figure this out as well!

Cheers Darren and others!

---

p.s the crank pulley and bolt is what holds the lower belt pulley in against the block / belt on.

Ah right, I knew the bolt held both pulleys, and did put that back to turn the engine with. Didn't realise the aux pulley acted as a guide though, but makes sense now you've said!


Was the first cambelt I've ever done anyway (never did one at college on mechanics course lol), so besides the aux pulley fail it went well, will know for next time at least!

[JamesG]

Was the first cambelt I've ever done anyway (never did one at college on mechanics course lol), so besides the aux pulley fail it went well, will know for next time at least!

It's all a learning curve

[Toms306]

Yeah, it definitely is James. Was really worried about it if I'm honest, getting timing out or tension wrong....but so far the hardest part was removing the bloody covers!

*Cue a thread about valves meeting pistons tomorrow.

[C.A.R.]

More confident seeing you get this done tom. Would be something I'm keen to do myself too as can't justify the cost of getting it done by a garage right now.

[HDi--Power]

More confident seeing you get this done tom. Would be something I'm keen to do myself too as can't justify the cost of getting it done by a garage right now.

Once you understand the principal behind locking the cam and loosening the 3 13mm bolts to allow the pulley to float its a very easy job

[cully]

Once you understand the principal behind locking the cam and loosening the 3 13mm bolts to allow the pulley to float its a very easy job

be warned though dont over tighten those 3 13mm bolts on the cam pulley as that is what fractures the pulley! then over time the pulley will break up

que thread: my pulley has broken what do you think caused it

[Toms306]

They're 20Nm according to Haynes.

This seems ok now, since fitting the lower pulley lol. Havent actually started it yet though, not sure I dare.

[Tom]

Do it!!