clinter

Ok...I just bought a 93 NA (88,000). It seems to have a harsh metalic whurring noise that increases with vehicle speed. It does not seem to be related to the engine speed (when I take it out of gear and coast, the noise continues). It also does not appear to be realated to the brakes.

My thoughts are some type of bearing, probably a wheel bearing.
Has anyone else had a similar problem?
Has anyone replaced or repacked the bearings? If so, what kind of job was it? Any tips?
There is also the possibility that this is normal for this car, but I don't think so.

Thanks,
Clint

gbhrps

Can you tell if its a front wheel or back wheel? Does making a turn on a winding road change the volume or tone of the noise, enabling you to identify which wheel is the culprit? If so, its most likely a wheel bearing. Changing the bearings is not a big job if you're mechanically inclined, have the tools, and a place to do the work. The hardest part is driving the bearing races out of the wheel hub. You can take it to a mechanic and have him press them out and install your new ones on a 20 ton press, or if you're careful and patient, you can use a punch and hammer and drive them out and install your new races in the same manner, but you must be careful not to scratch them while using the punch. Repacking the bearings with grease, troquing the axle nut to the correct preload, and reinstalling your caliper is not all that bad. If any of this sounds scary, let a professional do it. Check out the FAQ and TECH sections of TwinTurbo.Net for procedures. Good luck!

clinter

Thanks for the reply. I have not been able to distinguish which wheel it is comming from. Nor have I been able to detect any change around a corner, etc. That is why I am questioning wether it is a wheel bearing....

Anyway, assuming that it is...I have repacked bearings on my rodeo...so I am familiar with the procedure.

Does anyone know what tools (bearing nut wrench) and part numbers of those tools, as well as torque and preload specs.?

I have looked for this proceedure in the tech pages and I did not see it. I would be happy to take notes and pictures if anyone is interested.

Also what is everyone using for manuals?...factory?...Chiltons?

Thanks,
Clint

gbhrps

I'm using the 1990 ZX factory manual and, upon closer inspection of the procedure, I'd definitely take the wheel hub assembly to a mechanic who is set up to press out the old bearing and press in the new one. The manual shows that there is a ring clip that holds the bearing unit inside the hub that can be removed with a screw driver. (Obviously reinstall it after the new bearing is in.) The entire bearing assembly is prelubed at manufacture and requires no further maintainence. After reassembly onto the car they say to turn the wheel hub 10 times in both directions, and then check the bearing preload as measured at the wheel hub bolt: 5.9 - 37.3N (0.6 - 3.8 kg, 1.3 - 8.4 lb) (NSK bearing) or 7.8 - 57.9 N (.8 - 5.9 kg, 1.8 - 13.0 lb) (NTN bearing) and the axial end play .05 mm (.0020 in) or less. As for special tools, the only ones shown are the 20 ton press, a bearing inner race puller ST30031000 (J22912-01), and two different wheel bearing drifts ( one to remove the old bearing and another to install the new one). Best of luck!