Technical 100hp timing woes

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Technical 100hp timing woes

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Nov 11, 2019
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Hi All,

Ive been experiencing some issues while trying to set the timing on my ‘09 100hp.

The cam belt failed and valves bent. Ive had the head reconditioned with new and skimmed at the engineers. After reassembly and following the elearn guide to set the timing the engine won’t rotate. My question is this. After the head is skimmed do you need to use a shim plate or thicker gasket? I had a mechanic friend come out and check my work but he did pretty much what I had already done for the same outcome. Insights and help are much needed!!

TIA!
 
Did the crank rotate freely before putting head back on?
Is the gearbox in neutral? Don't laugh it's easy to miss.
 
Please post pictures of the timing marks you are aligning. Plus photo of the position of cam shaft lobes on number 1 cylinder when mark you using is lined up.
 
the camshaft sprocket on the 100hp engine is not keyed to the camshaft .

Did you set the pistons all at the same height in the cylinders?

Loosen the camshaft sprocket?

Set the exhaust camshaft in correct position and lock it using special tool?

Then fit belt kit , then tighten cam sprocket bolt while counter holding sprocket?
 
The 1.4 engine is timed with all four pistons at 1/2 stroke. You need four equal length dowels and put one down each spark plug hole. The crank is set correctly when the tops are all in line. You will also need to lock the cam. The belt is fitted and tensioned. Finally, the cam wheel is locked up and the cam locks removed..
 
The 1.4 engine is timed with all four pistons at 1/2 stroke. You need four equal length dowels and put one down each spark plug hole. The crank is set correctly when the tops are all in line. You will also need to lock the cam. The belt is fitted and tensioned. Finally, the cam wheel is locked up and the cam locks removed..



Yes this is exactly how we did it... mdc with the cams locked. I used the window at the back of the cambox. Everything i did was according to the elearn guide... I didn’t have the locking tools so I used a trick i saw here on the forum with a hex bit....
 
Yes this is exactly how we did it... mdc with the cams locked. I used the window at the back of the cambox. Everything i did was according to the elearn guide... I didn’t have the locking tools so I used a trick i saw here on the forum with a hex bit....

Without special tools how did you hold the cam sprocket while tightening bolt?

We're the cams timed correctly to each other when head reassembled? If cams not timed to each other that could cause your problem.

I don't know about the trick for locking cams please add link , is it possible that cam can be locked in wrong position using trick.
 
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Without special tools how did you hold the cam sprocket while tightening bolt?

We're the cams timed correctly to each other when head reassembled? If cams not timed to each other that could cause your problem.

I don't know about the trick for locking cams please add link , is it possible that cam can be locked in wrong position using trick.



I don’t understand how the cam can lose timing when the cambox wasn’t disassembled?? I removed it complete and then took the head off for reconditioning with new valves stem seals etc...

I didn’t undo any of the bolts/nuts on the cam sprocket?
 
I don’t understand how the cam can lose timing when the cambox wasn’t disassembled?? I removed it complete and then took the head off for reconditioning with new valves stem seals etc...

I didn’t undo any of the bolts/nuts on the cam sprocket?

In that case the inlet and exhaust cams are still in time.

Is gearbox in neutral?

Did you put equal length wooden rods through all spark plug holes of cylinder 1 and 2 to find mid stroke position? Or even better 4 wooden rods one in each cylinder.?

Are you 100% certain cams locked in correct position using improvised tool?
 
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In that case the inlet and exhaust cams are still in time.

Is gearbox in neutral?

Did you put equal length wooden rods through all spark plug holes of cylinder 1 and 2 to find mid stroke position? Or even better 4 wooden rods one in each cylinder.?

Are you 100% certain cams locked in correct position using improvised tool?



Ye pretty sure cos they’re solidly locked in place...
 
Take off the cambelt and see if the crank moves at all. Obviously don't do a full rotation. Likewise with the camshaft.



It does. We fitted and refitted the belt each time the mech tried to do the timing... rotated the crank to reset the position before attempting to set timing again.
 
Ok it looks like there is only one notch in camshaft to lock position and I went through other threads and found the 10mm Allen key trick.
So I agree cam likely in correct position.

I see you have replied crank can turn.

How did you find mid stroke of pistons.

Is the pip on crank sprocket at about 7 Or 8 o'clock when you set crank to mid stroke?
 
Is the water pump seized? Is that why cam belt broke?
 
Ok it looks like there is only one notch in camshaft to lock position and I went through other threads and found the 10mm Allen key trick.
So I agree cam likely in correct position.

I see you have replied crank can turn.

How did you find mid stroke of pistons.

Is the pip on crank sprocket at about 7 Or 8 o'clock when you set crank to mid stroke?

I said earlier. You need four equal length dowels. Drop one down each spark plug hole. The engine is at 50% stroke when the dowel tops are level.

You also need the correct cam locking tool/pin. If it is loose the cam will not be correctly set.
 
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