Need Help 944 cam belt moved

[nebz]

I hope this can be corrected without a major issue. I was adjusting the tension on my belts and accidentally loosened the cam belt tension before getting to TDC. When I started to turn it to TDC I know the belt slipped on the lower pulley and the top turned. Didn't do anything violent and noticed right away. Hoping there is a way to get everything lined back up at TDC. Help is appreciated.

[Bradical]

Someone might have a better recommendation, but if you pull the cam tower all of the valves will be closed and you can rotate the engine without worrying about bending a valve. It will cost you a cam tower gasket of course.

[John_AZ]

Have you read Clarks Garage for info?

Timing Belt and Balance Shaft Belt Installation

Or complete shop information to get the timing marks to TDC:
Clark's Garage Home Page


J_AZ

[nebz]

I read all of the Clark's garage info. Doesn't seem to address realignment if you didn't start at TDC. Is their a mark on the flywheel at the bottom? Thankfully I only went a few degrees before I noticed. Never made any sounds on the inside. Hope its OK.

[pfarah]

I wish I had an answer; I do feel a little nervous for you though...

[PA_944]

You can rotate the crank by hand, as long as you don't force anything you won't damage anything.

If it only jumped a tooth or two you will be all right.

I had to do one years ago when the owner removed the belt with the timing marks not aligned and then tried to move the crank to top dead centre without the belt?

He gave up when he "locked" the motor.
It took a bit of turning the crank and then the cam but we got it back in the end with no damage.

The damage occurs when the belt breaks when the engine is running as the crank will continue to turn over after the cam has stopped or when cranking as the starter will try and turn the engine over even if something is misaligned.

Do it by hand and you'll be fine.

[PA_944]

Oh and if you cannot find the crank timing mark pulling the plug from cylinder 1 and using a long screw driver will show you where top dead centre is, it will be when the screw driver is at its highest.

I would pull all the plugs anyway to make turning the crank easier.

Obviously if you use this method or any other after having the belt jump you should rotate the engine by hand three or four times after the new belt is installed and tensioned to check for any clearance issues.

[Bradical]

It's really, really important to realize that only a tiny bit of rotation on the crank equates to a lot of piston movement. If you use the spark plug hole method I recommend using something like a Mickey Dees straw. When you are doing this the top of the cylinder is at a 45 deg angle to the plug hole so if you let the screw driver fall down too the bottom and you could bind it and risk scratching the top of the cylinder, probably not a huge deal but I wouldn't want to do it. Once you got it set verify you have OT at the top near the reference sensors and the notch at the bottom of the flywheel is centered as well.

Like I said earlier, to completely eliminate the risk (or the anxiety) of bending a valve, pulling the cam tower will put all the valves all the way up.

[nebz]

Thanks guys. Feeling better. I don't think anything is damaged, just some work ahead of me. Slow and easy and I should be able to fix it.

[PA_944]

Bradical,

There is no risk of valve damage when turning the crank by hand.


The spark plug method is only to confirm TDC so there is no chance of cylinder damage as the piston will be near or at TDC when you do the test.

This is a very simple motor and people should not be afraid of it.

It's just an 8 valve interference motor, nothing really compared to a 16v or 32v like most European cars have these days.

[Bradical]

Originally Posted by PA_944

Bradical,

There is no risk of valve damage when turning the crank by hand.


The spark plug method is only to confirm TDC so there is no chance of cylinder damage as the piston will be near or at TDC when you do the test.

This is a very simple motor and people should not be afraid of it.

It's just an 8 valve interference motor, nothing really compared to a 16v or 32v like most European cars have these days.

I agree, just a recommendation to mitigate or eliminate the anxiety.

[nebz]

Thanks for the advice. I am happy to report that I turned everything slowly by hand until all of the marks and obvious indicators were aligned again. Redid the belt job and my car is purring beautifully once again!

[JAXTURBO]

I know I'm late to the party, but happy to hear things worked out. Some tine ago I put on my cam tower and realized I was not at TDC... before I installed the belts. However I couldn't get camshaft mark to line up. I don't think I removed the tower. I think I removed most of the retaining bolts except the corner ones. That reduced the interference enough to turn cam by hand to get mark to TDC.