Timing mark problem.

[minny]

I changed my timing belt today and I hit a problem with the timing mark on the cam sprocket. It was perfectly lined up, but when I put the tensioner on the mark moved back a few mil, 4 - 5. So I redid it, same thing.

Is this normal, because it seemed to be the tensioner moving the cam sprocket backwards a little. When I put it back to the timing mark on the second time there did seem to be some easy play in the sprocket, and look to be near impossible to me to keep the marks lined up perfectly while putting the tensioner back on.


Also, the timing marks on the crank. If that is lined up with the cam is that fine, because it moved off it's mark again, I rotated it twice , but had to do this a few times because it so easily slipped, eventually I got a neighbour to hold it still and it is peg on. But not sure now if it's tdc on cylinder 1 or 4.


In short, is it ALWAYS at TDC cylinder 1 when the timing marks are aligned.

If not is there a way of checking to make sure.

Thanks.

[minny]

OK

I just done some googling and i finally found someone who had a similar problem.

It seems to be to do with the number of teeth on the belt. The old belt that came off had 152 teeth, it was the old obsolete damper. The new style tensioner and damper has 153 teeth.

Is it possible to line these up? Or do i go and by a 152 toothed belt, trouble with that, I was informed they wouldn't work with the new style damper and tensioner.

HELP! :aargh4:

[hibbsy21]

Hmm this is worrying. I need to change mine soon, i have no idea how many teeth i have. Sorry i cant be of any help but good luck on finding a solution, keep us posted!

Rich

[minny]

From what i have read the 152 belts are all but obsolete, but you can still get them. The 153 should be used with the 'newer' ie 79 onward, damper.

It's just an absolute pig to get on. Not sure what I can do.

[minny]

OK Rich, I managed to do it and this is what I did.

I know you cannot move the cam sprocket whilst the crank is on it's timing mark. However, it suddenly dawned on me that it said nothing about moving the crank whilst the cam is on it's mark. I look to see how far the out I was, and it turned out to be about half a tooth. I so i rotated the crank round and and left it about half a tooth behind the mark i had made. That is, the mark I had made on the crank sprocket and the one on the head where not in line, the one on the crank being about half a tooth distance behind. I then put the belt on and rotated the crank clockwise with a socket so that the marks i had made where now in line and held this steady with my knee while i put the brass bit on the tensioner pulley and pulled the pin.

BINGO, both the cam and crank alignment marks are now in line or near as possible, in addition, the rotating of the crank clockwise to put the marks i made in line really tightened the belt that goes over the intermediate sprocket, not a smidgen of slack there.

I made two lots of marks, I aligned the mark on the crank pulley with the lower timing belt cover. Took this off, then I made, with permanent ink marker one on the crank sprocket and head, it is this i use to align and then check with the other on the lower cover.

Has regarding my query about TDC on the first piston. I thought about this last night and read that you can feel the compression on your hand, I though placing some cling film over the spark plug housing (with plugs removed) would give a better visual indicator, be careful to remove the cling film when not on compression stroke since it will suck it in the engine.

What I found though was the compression seemed to be at both 1 and 4 cylinders at the same time, made me assume that 1 and 4 where on compression together likewise 2 and 3. Not very helpfully, but what I did in the end was just get a touch and shine it down the spark plug, you can actually see the piston, just watch for it coming up as you rotate the crank. Hopefully that meant it was TDC on cylinder one.

Not had time to turn the engine on, but i have rotated the engine by hand with out the spark plugs in, and things seem to be doing what they should.

I hope that is of some help to you.

Does anybody know the best way the remove the thread but out of it's hole when the bolt head shears off? Is it jus a case of drill?