Cam belt snapped on Peugeot partner please help!

[Gibbo2286]

The normal position is for pistons 1 & 4 to be at TDC when the flywheel is pegged so if you set the camshaft so that the valves on No 4 are 'on the rock' i.e. the exhaust just closing and the inlet just opening it is then in/near the firing position for No 1 and the holes for the camshaft should line up, maybe half a hole out due to the preset advance.
Fit the belt when you have that all set up then remove the pegs, rotate the crankshaft forward two full turns and recheck that the peg holes still line up.

[RichardW]

I'll have a look later and see if I can find the procedure for replacing the cam shaft on this engine. If the camshaft is near enough in the right (timed) position when you offer it up, then there should be no problems.

[JayRenton]

Thanks mate I’m having a nightmare now!!
I actually spoke to a Peugeot specialist this morning and he said these engines are timed up wth the pistons half way down the bore.
So I left the crank pinned with a 5mm drill bit on the pulley side and then fitted the cam which bolted down fine and turns freely, I then fitted the belt and timed it up fine.
Now I’ve gone to turn the crank and it comes to a clunk as if the piston it touching a valve.
I can’t understand it, it’s seems such a basic set up am I missing something?

[JayRenton]

Could the timing be 180 degrees out? Somehow?
I’m thinking the crank turns twice and the cam turns once?

[Gibbo2286]

Could the timing be 180 degrees out? Somehow?
I’m thinking the crank turns twice and the cam turns once?

That's correct cam runs at half the speed of the crank, I suppose might be possible that you have it 180 out.

[Peter.N.]

I don't think it actually makes any difference, as long as the valves are in the correct relative positions with the pistons, I cant think of anything which will know the difference - but I could been wrong in advance.

Peter

[JayRenton]

Ok I’ve sat down and had a beer and my brain has gone into over drive.

I need take the belt off rotate the cam 180 from its pinned position then put the belt back on rotate the crank 360 and that should be it.

[JayRenton]

That didn’t work it still catches although a bit further around.
I know the crank rotates freely as I tried it before I bolted the cam down and the cam defiantly spins free so it must be the timing, i’m beat!!

[sparksie]

Hmm
You're going to have to use the flywheel timing holes.
If all the pegs go in, it will be correct and there will be no clunk.
Set the cam first, both because its easier and its harder to do damage turning the crank by hand.
Sorry, the flywheel one is a bit of a pain to get to and, knowing this, I always mark the pulley, if it hasn't got timing holes in, before I start.
You couldn't do that, because the timing was already lost, so you'll have to use the flywheel holes.
Others will doubtless be along shortly with tips to make it a little less difficult.
Good luck

[ekjdm14]

I don't know if this has a similar "gotcha" to some other engines (IIRC the old XUD had this too?) where there's actually TWO holes in the flywheel, one the timing hole and another for I don't know what. I seem to recall the actual timing hole was a good fit and the "false" one was a bit sloppy/larger if that helps.

I suppose you could try and turn the crank a little forward and back from the hole you have now while trying to insert the pin, and see if there are any other possible locking points.

EDIT-: just noticed you used a 5mm pin in the pulley to time it up, is this the procedure or is there a flywheel locking point as well? seems like a locking pin in the pulley would be a lot more susceptible to any free play in the pin arrangement than if it were locked at the flywheel... IF there's a locking hole in the flywheel then use this instead of the pulley.

[JayRenton]

Cheers guys but I think on my engine the the flywheel is just used to lock the crank to remove the pully bolt!
The actual timing pegging point is on the pully side of the crank. Unless I’m wrong.
I think I’m going to strip the covers off again and take the sump off so I can actually see where the crank is.

[JayRenton]

The flywheel locking point is in a different position to the pully locking point and I’ve watched guides on changing the timing belt and all of them use the pulley locking point.

[sparksie]

Yes, I always do too, when it exists.
Since dual mass pulleys, there hasn't always been a pulley locking point and I've been making my own marks, but, as I said earlier, the OP hasn't got that option.
I also read somewhere, perhaps on here, about pulleys that had the holes in the wrong place. If memory serves, the flywheel holes were used to solve the problem. My understanding has always been that the flywheel is the definitive datum and everything else is timed from there.
I've been lucky, so far, with PSA lumps. I've never had to rebuild one after a catastrophic failure.
Back in the day, when engine rebuilds were economically viable, all rotating parts had timing marks cast/scribed into them and success depended on checking these visually at every stage of assembly. To be honest, I think I preferred it, but the modern way is more foolproof.
In all the upheaval of the last year, tools have become scattered and I have no idea where my locking kit is. I have a feeling 5mm may not be correct, but as I never used the flywheel pin, I may be misremembering.
It is good practice to have all pistons down the bores while fitting the head, just in case, but I'm pretty sure the actual timing is at tdc.
It certainly is with other manufacturers

[JayRenton]

Cheers, I’ll give it a try, I’m hoping I can rotate the crank around enough to pin the flywheel whilst jiggling the cam around keeping the valves out the way too

[RichardW]

I had a look at the procedure this morning - there is nothing about rotating the crank when refitting the cam - it just says that the cam should be at timing position when bolted down - there is a mark on the end which can be lined up with the hole in the cam carrier so that it is in timing position.

The pin in the pulley is used to time the engine - the flywheel locking (above the exhaust) is not in the timing position, and is only used for loosening / tightening the crank pulley bolt.

I would take the belt off again, and remove the belt sprocket on the crank to make sure that the woodruff key is still in place - sometimes when the belt goes, the woodruff key can shear off, and this puts the crank sprocket (and therefore timing) out of synch with the actual crankshaft.