My brother has a 1997 Honda Accord 2.2L He removed the valve cover and cam gear to replace the cam seal. Instead of completely removing the timing belt, he ziptied the timing belt to the cam gear so the timing belt wouldn't move. I understand this isn't likely a recommended method, but that's the way he did it. So he replaced the cam seal, and when attempting to put the cam gear back onto the camshaft, the cam gear keyhole (assume that's what it's called) doesn't line up with the key on the camshaft. If you take the key out the cam gear will slide onto the camshaft, but with the key installed in the camshaft keyway, the key and keyhole are misaligned by just millimeters. Since it is such a small measurement, I don't think the belt slipped a tooth or anything. I was thinking perhaps the timing belt tensioner tightened when he took the cam gear off, but I really have no idea.
Any ideas and/or solutions are appreciated!!!

 

It's possible the camshaft moved a bit because the valve springs push on the cam lobes.

Did he start out with the engine at TDC? Or is it a random position? He'll have to really check the cam timing to be sure.

Is it possible the cam belt has skipped a tooth down at the crankshaft sprocket?

The tensioner wouldn't have done it, because it's locked in position. This engine doesn't have an active tensioner. It's only got a weak spring and you lock it in place by tightening a nut through the lower timing cover.

 

A quick and dirty fix would be to make sure everything's at #1 TDC, remove the rocker arm assembly, slide the cam gear under the belt, tilt the cam back down in position, and replace the rocker arm assembly. Then double check the cam timing.

 

Thanks for the replies JimBlake and Roader
He said he set it at TDC by lining up the cam markings. Not sure if it slipped a tooth on the crankshaft, but I suppose it is possible. The reason I figured it didn't slip a tooth is because the distance it is misaligned is nowhere near a full tooth, only a few millimeters. The valve springs pushing on the cam lobes like you suggested makes sense to me. Can it be lined back up without removing the rocker arm assembly by simply turning the camshaft or crankshaft? Or is that a no-no?

 

Turn the crankshaft just a bit. Using the bolt in the center of the crank pulley, that will be easier than turning the camshaft (which has nothing to grab).

When you get the camshaft sprocket back on, make sure you verify the cam timing marks carefully before spinning anything.

 

As long as the word "up" on the camshaft pulley read right side up it should be OK. To avoid a bad surprise, crank the engine over a few times by hand, with the crankshaft bolt, before you spin it with the starter.

 

Ok cool! We'll probably knock this out tonight then. One last question: I was told by someone who claimed to be an ASE mechanic that by replacing the cam seal the way my brother did, just pulling off the cam gear with the timing belt still attached as opposed to completely taking off and redoing the timing belt, that the timing belt tension will be wrong and the belt will snap within a week. Any truth to that??

 

Semi-truth. After doing that, I would at least check the timing belt tension. You should absolutely double-check the camshaft timing.

Cam-timing belt tension isn't supposed to be TIGHT like an alternator belt. Check the long span of the belt, closest to the radiator. You should be able to twist the belt somewhat less than 90-degrees with your fingers. Trouble is, without removing the lower timing cover, you'll have trouble grabbing it mid-span.