JohnLX300

iTrader: (2)

About 4,000 miles ago I had my timing belt replaced with the water pump and the 2 idlers and the tensioner. But, now everytime I drive I hear what sounds like a bad bearing noise. It happens only when the car heats up. I started it this morning....no noise...then I drove and let the car heat up and the noise came back. It seems to be coming from the center of the block. Any Suggestions?

sktn77a

iTrader: (2)

Yes, take it back to whoever did the work and ask them. It could be an alternator or AC condenser bearing going bad (which, in turn, could be due to an overtightened accessory belt). Is it a metallic screeching/chirping nosie, or a typical squealing belt-type noise. Bearing noises are usually worse when cold and go away when hot. Try squirting some water on the belts. If the noise goes away, that would point to the belts. If they aren't toyota belts, they may be more prone to noise (based on my limited experience with toyota vs aftermarket belts).

code58

John- Were the parts replaced at a Lexus or Toyota dealer or independent? What I'm getting at is if the parts were replaced with OEM parts or aftermarket parts. I would never use anything but OEM parts on a T/L, not driveline anyway. I used a Goodyear Gatorback timing belt on my DIL's RX and replaced it at 30k mi on the belt. I'll not do that again.

JohnLX300

iTrader: (2)

I did use all OEM parts and had my local toyota dealer replaced all these components. Earlier today, I bought my vehicle back to toyota, they replaced the timing belt....stating that is was defective. Now, the sound isn't as loud as it was before but its still there. Its about 50% of what it was before. And I notice that it is the loudest when the engine is warmed up, when the engine is completely cooled you can't hear it at all.

code58

What did they say about the fact that the noise is still there (even if reduced), or don't they know about it yet? If they used OEM parts on it, I can't imagine why a T/L timing belt would go bad, especially in a short time. They are one of the best belts I've ever seen. Also can't imagine why it would make a noise. What kind of noise did (or does) it make. And if it was a defective timing belt, why didn't the new belt get rid of ALL the noise? Something not right with this picture.

Also, I can't imagine why a timing belt would make a "bad bearing noise". Still say something isn't right here.

JohnLX300

iTrader: (2)

I just bought a stethoscope last night, this morning I turned the car on. the noise was from the center of the engine block, but very faint. Then I wait for about 10 minutes now the noise was a lot stronger, not as strong as before, but stronger then when i first started it. I have access to alldatadiy, and pulled up the timing belt/water pump diagram. From the diagram, the part that is making this noise is the water pump. Which would make some sense, being that the noise is low when the car is cold, and when it heats up and the thermostat opens and the coolant rushes to the water pump the noise is considerably louder. Also, the week before they replaced the idler right about the water pump saying that, that was the issue. What do you guys think?

code58

John- I assume you meant to say "right ABOVE the water pump". Right? The OEM Aisin water pumps are the highest quality and most finely engineered I have ever seen, but i guess even then it's possible to get a bad one. This is tricky and I wouldn't even suggest it to anyone who i didn't think was VERY careful but I have pulled the top bolts on the timing belt cover and used a MS to try and trace a noise in that area. I would suggest blocking the cover out rather than trying to hold it though. The MS should definitely tell you if it is the W/P though. You should be able to get to the W/P with the MS even if you have to place the probe on the pump and then have someone start it WITHOUT TOUCHING THE THROTTLE! Good Luck!

JohnLX300

iTrader: (2)

Update to this situation, I have been bringing my 99 RX300 to the toyota dealer on my spare time for this same issue. After having them tear down the passenger side to finally fix this issue. They even had their regional master toyota tech tear it down because I complained so much about the quality of workmanship of whomever was working on my vehicle. They master tech stated he spayed the belt with brake cleaner, the noise stopped momentarily. He stated after calling a couple other regional master toyota techs, that the OEM Toyota belt will sometimes make this noise, their solution after trying out various timing belts was the Napa branded timing belt, which is made by Gates for Napa. They are in the process of the repair now and I should now by tomorrow if this was the solution.

JohnLX300

iTrader: (2)

The issue was solved by the new timing belt. Surprised that no one else had the same issue with the OEM t-belts.