Yet another timing belt question

[mmstingray]

So I replaced my timing belts yesterday. I did everything according to the book (Clymer). I had the mark at "T" (there is no "T1" as the book says), and both camshafts were right where they should have been. When I took the right belt off, the pulley advanced a couple degrees ahead. Before I put the belt on, I rotated the pully back to where it was supposed to be.

Now, the tension on the left belt is good. That is, the side of the belt that doesn't have the tensioner is semi-taut and not floppy. That's not the case with the right one. Is that normal?

Also, I am SO paranoid of damaging the engine, I've been truning it by hand using the kickstarter. I have yet to start it. If the valves were to hit the pistons, would the engine even turn?

[ozzie]

MM, no this is not normal. When I was trying to figure out a miss/backfire problem I replaced both belts. In the process of diagnosing the problem I removed and installed the belts many times( at least 4). I am very familiar with the condition you are talking about and here is what i have found: Due to the way the cams/crank operate, one half naturally tensions against the rotation, that is ; the "top" side or the side without the tensioner is normally taught due to the valve springs wanting to rotate the cam ever so slighty. The other side tensions opposite that. When this happens the side without the tensioner rotates in such a way as to let slack occur. What I did to counter that was to route the belt over the tensioner side first. This way no slack is available. It may take some "trial and error" but it can be done. Whatever you do make sure there is no slack at all in either belt and that when tensioned, the timing marks on the cogs line up with the marks on the case. Forgive me if i have confused you to the point of desperation Hang in there thereis plenty of help to be had here

ozzie in sapulpa

[Whiskerfish]

I have run into the same thing on belt installs. I believe it is due to the valve spring tension "pulling" that cam in that direction and creating a bit of slack there. On mine the left side is nice and snug and the right side will have a fair amount of play. Mine were not to the point that I felt I needed to take any action and I left them alone. But if you are concerned You "might" line things up at the proper marks and then Loosen your Tensioner and using a wrench on the RH Cam pulley rotate it just a half a degree or so backwards to remove the slack, then set your tensioner again. That should help alleviate the slop you see on the top of the belt. Again when you are done do several rotations by hand making sure everything stay where it is supposed to.

[mmstingray]

Sweet fancy Moses do I ever love this forum. Thanks guys. I'm gonna go try again in a couple minutes.

[octane]

So I replaced my timing belts yesterday. I did everything according to the book (Clymer). I had the mark at "T" (there is no "T1" as the book says)

..oh yes there is...sort of;

if you turn the crank a bit away from the T you will find an F and the a "1".
(Refers to cyl. 1 and 2)

On the 'opposite side of the crank you'll find a T and a F and a 2.
(Refers to cyl. 3 and 4)



As WF said...

Check this, how to take up 'slack'







PS
A "How-To change timing belt" thread will be up and running later today
in the How-To 4 Wings" forum.


EDIT: here' an exclusive preview ha ha ha:



..tension-roller LOOSELY attached
..take up tension with 12m ring-spanner so pulley is EXACTLY on mark
..strip spanner to frame.(the pulley 'wants' to turn, as it is 'riding' on the
cam slope)
( re-check position of pulley-marks (looks out of mark on photo, but that's because of the angle from witch it was photographed)
and check crank mark )
..position belt on pulleys/tensioner
..let spring preassure 'automaticly'make nessesary tention
..tighten tensioner bolts

I had to re-do it to get the same tension as on the other
side.(witch is not affected by the 'reverse-tension')

Last time I did this thing I held on to the crank this way
( as I only have two hands)

[mmstingray]

Great stuff as always, Octane.

Well, somehow I go the belts to be the right tension and all the marks were where they should be. I cranked it by hand first and all seemed good, so I started it. Ran just fine with the choke on and everything, until Boy Genius suddenly realized that he forgot that he left the flywheel cap off and got oil all over the place.

Magnificent.

So I sprayed the engine down with degreaser and hosed it off. Now it runs horribly, stalling if I don't keep it above 3 grand. I suspect I got something wet I shouldn't have.

[mmstingray]

The timing belt thing seems to be okay now. Now onto the other issues:

http://www.ngwclub.com/forum/viewtopic. ... ght=#26037