timing problem, need urgent help

[mytos232]

hey guys

i cracked open the timing covers today to change the timing belts and none of my timing marks line up, one cam is 180 from where it should be and the other is 90 from where it should be. what can i do? do i just try and rotate the cam pulleys?

[Track T 2411]

A little history on the bike might help... had it been running this way? Have you tried to turn the engine over by hand? Are you certain you're looking at the right marks? Is the engine at top - dead - center on the compression stroke for the #1 piston?

Start at the beginning. If the engine has been running relatively ok before, you probably aren't at TDC of the compression stroke. The timing mark on the crank flywheel will be at TDC twice for every one revolution of the cams; the end of the compression stroke, and the end of the exhaust stroke. If the engine turns over by hand with no binding, try turning the crank one revolution and look at your marks again...

[RB]

Was this a running bike? Or can you spin the engine by hand with the crank shaft bolt? Turn until marks line up or the engine locks up??? If locks up you have a valve issue most likely.

[ericheath]

Which bike ?

Pull spark plugs to make it easier to rotate. If you’re at T1 and the pulley marks are that far off, I suggest you remove the timing belts before rotating the engine any more. After removing belts, loosen all the valve adjusters and back them out as far as they go. Then rotate the engine slowly back 1/8 to 1/4 of a revolution paying attention to which way you rotate it. You want the pistons down in the bores. If you feel resistance, stop.

You should now be able to rotate each cam pulley so each up mark is up and the timing marks very close. Then rotate the engine the opposite 1/8 turn back to T1. Put the left belt on. It goes on pretty easy. I take the slack out of the straight side of the belt (the one that is opposite the tensioner) and start it on the teeth from there, then around, pull the tensioner to the loosest setting and the belt should slide on. Check both the pulley timing mark and the T1 mark. They’re easy to nudge out of position. If they moved, try again.

The right side is the harder one because the number 3 intake(?) valve spring has a little tension on it. The valve is slightly open and tries to turn it clockwise. Again, take the slack out of the straight side. I hold the pulley firmly with the other hand and start the belt on the straight side. Once it’s on the teeth, pull the belt over the tensioner.

Check your marks, if they aren’t right, remove the right side and try again.

You can tighten left side belt tensioner, then rotate the engine around one revolution so the up marks are down and tighten the tensioner on the right side. Go slowly and listen as you rotate it a few turns.

If you’re off that much, it’s possible a valve got bent. Not necessarily, but possible. If it rotates freely after doing as above, you can do a compression check, or put the plugs in and see how it runs.

I think I have everything. Sorry if I’m oversimplifying it.

[mytos232]

its an 83 1100 it hasnt been running since i bought it, the crank turns over fine, the cams dont want to turn but i havent loosened the valves yet. im assuming whoever owned it previously tried to do a belt swap and did it wrong, but i dont want to ruin an engine and just yank on stuff.

[robin1731]

snip...…... the crank turns over fine, the cams dont want to turn but i havent loosened the valves yet.

That doesn't sound good.

.

[RB]

And it's confusing too!! the crank can't turn w/o turning the cams if the belts are on???

[ericheath]

I think you better follow the procedure I described to make sure you don’t cause any damage.

You need to get the belts off and pistons down an inch in the jugs, you could use a probe through the spark plug holes to ensure they’re out of the way.

Then you can turn the cams and see how it goes. If they’re stiff, you have issues.

I believe, but cannot swear to it, that when each “up” mark is at about 4:00, all cam lobes are away from the rockers.

You can see the lobes and base circles under the rockers.