Squeaking noise after timing belt replacement

[mikey]

Well, I was pretty proud after tackling my timing belt replacement. I realize that it's pretty easy on one of these cars, but my buddies are impressed nonetheless. There's a hitch though.... I'm hearing a squeaking noise coming from in there now, and it seems to be getting louder. I bought one of those kits that had a timing belt and an idler pulley for one price, and I used the spring that was on there before. I'm pretty sure that I got the tension about right, and the engine runs smoothly. Could the new idler pulley be bad? Could too much tension, or too little, be the cause of the noise? I hate to think of going in there again, but I would at least know my way around now, and it should be quicker.

By the way, I replaced the water pump too, but the squeaking is there even with the pump/alternator belt off.

Any ideas?

[Petros]

Tensioner is a likely culprit. That is why I do not use aftermarket ones. The belts are fine, but I have found many of the Tensioners do not hold up, and can squeak. IT is easy to get to by just removing the upper timing cover, I think you can swap it out without removing anything else. If your old tensioner is smooth and quiet when you spin it by hand, I just reuse them, and I have never had one on a Tercel go bad. I have had the tensioner bearing go bad on other cars, but never on a Toyota.

Might try and easy test: remove the timing cover and start the engine so you can hear the squeaking, than spray WD40 on the bearing while it is running (try and keep it off the belt!). If the squeaking changes or goes away, it is the tensioner.

[mikey]

Thanks for the tips....

I'll check it out when I've got my next day off and post an update. I like the idea of getting in there without having to remove the lower cover (and thus the pulley, radiator, etc.), and if I remember, the tensioner pulley and its bolt are just accessable. Gotta be sure not to drop the spring down in there, and keeping dirt off of the belt should be easier, because I cleaned everything off during the last repair. I'll be happy if that's the problem, but it is sad that the original part lasts forever, and the replacement could be bad after a few dozen miles!

[mikey]

Problem solved ( I hope): I took off the upper timing belt cover, and WD-40 on the tensioner did not change the noise. So I removed the tensioner pulley and compared it to the old one, and the new one seemed quiter and smoother, and when I re-installed the old one it was even noisier. So I put the new one back on and proceded to step 2, which should have been step 1, it turned out.

A few days ago I posted about tightening the crankshaft pulley bolt, and it hanging up due to possible damage to the threads. I got a torque wrench on it today and the dang thing tightened even further, about another whole turn. It's seated well now, I'm certain. I think the squeak was sort of a rattle/squeak, and the likely culprit was the timing belt guide, probably shaking a bit. That's my current theory, and I'm sticking to it!

P.S. I was nervous about the timing belt jumping a tooth on the gear while the tensioner was off, so I tied a piece of rope around it to keep it sort of tight. Made me feel safer.....

[Petros]

I always double check the timing marks when ever I have done anything under the timing cover. Easy check, solves potential big problems later. It paid off only once, but once was enough to keep double checking timing marks.