Vibration / Buzz at Right Motor Mount - 3S-FE

[deddy]

1990 (built 08/89) Camry with 3S-FE and 5 speed. 168K miles.

I have finished the Timing Belt, Water Pump and seals, etc. and the engine is tight and leak free. Now I've turned my attention to addressing the vibration and noise at low RPMs (that was present before the repair).

Symptoms: This significant vibration / low freq buzz happens at a very narrow RPM range: about 650-850. The noise sounds almost like metal to metal contact. The noise is quite obvious when revving the engine in nuetral and when the RPM's drop through the 850 - 650 range, there is a distinct buzzzzz especially (when sitting inside the car) at the right side floor boards and dash area. I have crawled underneath and gripped the exhaust (with gloves) and the noise is not coming from the exhaust system (not a broken hanger or exhaust leak).

The noise is centered at the right side motor mount (next to the Timing Belt cover). I can lift the engine from below and when the weight is off the mount, the noise stops.

I removed the mount and inspected it. Unlike the front and read motor mounts that obviously degrade and tear apart, this mount doesn't appear to have damage.

I read most of the posts here on Camry I4 vibration issues (there's a lot!), but the consensus is a bit mixed. Some people report success when replacing the mounts, some say it's just a fact of life with these Camrys.

The engine runs fairly smooth - there is not a noticeable shake at idle (although it does seem a little smoother after about 1000 RPMs). I have set the ignition timing correctly and it has new plugs, wires, rotor and cap. I also cleaned the throttle body and EGR inlet (at the plenum).

Last year in another thread about vibration the good DoctorJ posted that Toyota changed this mount in 08/89 and added a 'spacer'. I'm not sure that I can identify a spacer on my mount, so I'm wondering what he might be referring to. When I remove the mount from the car the only two separate pieces are the mount and the thin rubber sheath that covers it.

I guess what I'm asking is:

1. Does your Gen 2 I4 Camry have such a noticable, audible vibration/buzz at this RPM range?

2. How likely is it that a new mount will eliminate the noise? (cost is $50)

3. I know the other motor mounts are shot. How much would they contribute to this particular noise? (cost $50)

4. Do these mounts 'sqwash' down from the weight of the engine? (there is no other apparent damage).

5. Suggestions?

Thanks for reading a long post.

Doug

[fredk]

[new echo owner]

Originally Posted by fredk

Is fredk thinking what I am thinking? If the mounts are bad, whether it is the cause or not, you will need it anyway, why not just replace them and see what happen.

N.E.O.

[deddy]

Good point.....

I can tolerate the bad mounts (front and rear) for the time being. They really don't seem to be causing any issues. I don't drive the car very 'spirited'.

I can't tell that the side mount is bad, at least not by looking at it. So I really don't want to 'bet' $50 that a new mount will fix the vibration without some reason to believe that it will. I have quite a bit of $$ in the car now, and there is still the A/C to fix. Just trying to prioritize my investments in this project.

Doug

[new echo owner]

If the mount is the cause, except for the vibration, it isn't going to cause you any problem. Sometimes, it is indeed difficult to tell if a mount is bad or not visually; however, if you put a new one side by side with the old, you just might notice the height difference. A collapsed mount can look good but would transmit vibration.

N.E.O.

[Doctor J]

The 89-90 right front mount [where the timing belt is] in crossection looks like the ball joint, except it is rubber filled instead of grease filled

Many times it fails if the bolt at the top of it is tightened to its torque before the rest tof the bolts. This causes seraration of the rubber inside and metal to metal contact. The online manual specifies the tightening sequence, but even followig one if rubber is older then 10 years, it could break.
The cracks and separations of the torque limiting mounts [aka one between the tranny and radiator,and tranny and crossmeber] cause hop at the gear shifts especially when going uphill [manual tranny].The TSB has been issued regarding this matter. But again, the vibration and noise at neutral is mainly to the "timing belt" mount internal metal to metal contact

[deddy]

A new mount from Autozone ($45.00) solved the problem. Thanks for all your suggestions and explanations.

Doug

[paladin_omega]

Which mount did you end up changing?

[deddy]

Well... as I said in the original post:

" The noise is centered at the right side motor mount (next to the Timing Belt cover)"