DOT3

I replaced the timing belt, crank seal, water pump and tstat. Put things back together and an intermittent high pitched squeak developed after a couple of days. I removed all drive belts and cranked the engine and the squeak still persists. Otherwise the engine runs good. Any ideas because I'm going back in Thursday.

1999 4runner
3.4l V6

Thanks

Fink

How many miles do you have on your rig?

Not sure about the squeak...maybe check the timing belt to be sure no foreign substance got on there, maybe some water was on there when you put it on...not real sure...just some ideas.

Fink

93ToyKid

Did you retract the automatic tensioner before you put it back in? The reason I ask is because we forgot to do this on one of our motorcycles, and it was fully extended, and therefore had the timing chain WAY too tight, causing a really loud squeak. Don't know if it would have the same effect on your motor or not, but just a thought.

DarylD

What belt did you use ? OEM or aftermarket . I've seen(&heard) aftermarket t-belts squeek .

DOT3

I've got 73k and all the parts are OEM.

I used the timing belt tool to compress the tensioner. The belt seemed a little tight to me because I had to remove the top idler pulley to get it to slide on. In other words, it would not quite slide over the installed pulley unless I removed it and pressed down on the belt with the pulley and then bolted it in.

The old and new belt looked the same.

????

MTL_4runner

I think the motorcycle engine setup is quite different from the 3.0 or 3.4L motors.

It could also be that one of your idlers is on the way out.
You might have to tear it back apart to find the squeak or just live with it for a while (won't harm anything if it breaks).

I assume you put the old and new belts side by side and they were the same length (likely because otherwise it wouldn't run right either).

DOT3

Maybe it's too tight. I thought that when I installed it so I double checked that the tensioner compressor tool had fully compressed the tensioner. I thought it had so I proceeded. I attributed the tightness to a new belt.

I've got it in the garage right now with the skid plate off and all belts removed and radiator drained. All I need to do is remove the covers.

This was an interesting excerpt from minimopar resources:

The Timing Belt Squeak
Usually what happens is the timing belt idler pulley (towards the rear of the engine) that is used to tighten the belt gets polished over time. If the belt is also over tightened, a persistent squeak will result. To remedy this, you will need to take off the timing belt and you might as well replace it. See the Engine Timing and Belt Replacement page for more details.
Once you have removed the belt, you can deglaze the idler pulley with a piece or emery cloth. Just "sand" the pulley with the cloth until it looks uniformly hazy. You can also deglaze the sprockets to ensure that they are not glazed, but this takes more time and they usually aren't the cause of the squeak. It is a good idea to wipe the teeth and grooves of the sprockets down with a solvent to remove any oil or rubber deposits.
Reassemble and time the engine using the procedure on the Engine Timing and Belt Replacement page.

MTL_4runner

If you do this use some pretty fine paper (like a 320 or 400) to break the glazing on the idlers.

Fink

You did all those repairs with only 73k miles on your rig? Were you having problems? I've got 90k and all I'm doing is the timing belt and drive belts...do I need to do the water pump and crank seal as well?

Fink

DOT3

Fink;

The spec is 90K or five years. My 99 has 7 years on it so it was over due. The belt looked good but it appeared that the water pump was just starting to weep since their was some antifreeze residue on a bolt. That may be normal. However, the belts don't do well when their are leaks. The crank seal and tsat are only a couple of dollars.

Fink

OK...thats what I thought.

Thanks man!

I'll be getting mine done next week!

Fink

Rick F.

My 2nd gen had a persistent squeak that would temporarily go away with belt dressing and I found later that it was a misaligned pulley. Try that to determine if it's the belt or something worse.

sswearin1

2000 3.4L with 91k, had the belt and water pump changed (at 85k) by a very good mechanic (independent toyota only repair shop that the family has used for years) and i developed a quiet and intermittent squeak that has become a little more persistant. can you hear the squeak when driving? i can only hear mine when idling with windows open or with the hood open. i think i will learn a little more about how to safely remove and put back on the belts and try the sandpaper idea. could it be the alternator? is that even connected to the system? that is where my squeak seems to be the nearest too but my ears aren't that great. fink, my mechanic noticed that my water pump had a slight leak and i just had him replace it since he was in there... probably not a bad idea since your rig like mine was owned by someone else before us.

FilthyRich

do the water pump while you are there. You do not want to have to remove the belts later just to replace a water pump. Too cheap of a part to do the work all over again

Rick F.

Ditto.

DOT3

Rickf and Swearin;

My first suspicion was drive belts so I adjusted and dressed them and the squeak persisted. I removed all my drive belts and then cranked the engine and the squeak was still present. It has to be the timing belt or even the water pump. They are the only components left.

The squeak is lound and can be heard inside the truck. Sometimes it chirps like a warbler.

sswearin1

i not a wrencher, but i try to help with observations when i have something similar happening on my truck. DOT3, you sound more knowledgeable than me since i probably couldn't even id my water pump. wow, that squeak sounds loud, i hope mine doesn't get that loud, but keep us updated.

bear001

Have you tried to put a styiscope on the tensioner pully for the timming belt sounds like maybe it is to tight or maybe that was the problem in the frist place?? loosen the tensioner just a smige he he that just a little bit hope it works

MTL_4runner

How would you do that?
....the tensioner is hydraulic.

You might want to check the water pump and idlers to make sure both spin freely by hand and don't squeek.

DOT3

Like usual, human error.

The idler pulley bracket that the tensioner pushes against to keep your belt tight was broken. I think I compressed the idler with the tensioner compressor tool too fast. The second time around I read the directions and compressed the the tensioner slowly. Their was a lot less pressure on the idler bracket.

So far no warblers.