Steering wheel shaking at a stop - engine mount bad?

[AmTeC]

So My cb7's (auto) steering wheel shakes alot when in gear and at a stop, but not when the car's moving, or when its not in gear, some of the members here told me the front engine mount is usually the cause, I'm not exactly sure which mount is the front one, I assume the one right behind the radiator, I dont even know where the other two are. I'm also not quite certain on how to diagnose the engine mount. I put up the handbrake, put the car into drive, popped the hood and looked at the engine as it shook. It shakes more towards the back (towards the windshield) and less towards what I think is the front engine mount (behind radiator). My guess tells me that means the engine mount isnt absorbing the vibration, but rather transmitting it to the rest of the frame, I could be wrong. With the engine off, moving the mount shows that its sorta stiff, not alot. I dont have anything to compare it with so it could be normal.

[Fleetw00d]

There are four engine/transmission mounts. You correctly identified the front mount (aka torque mount). There is one at the left end of the engine about even with the head, one on the top of the transmission housing on the right, and the fourth on the main cross member attached to the engine via a bracket under the intake manifold.

Is the rubber in the front mount cracked?

If you have a 5 speed, the rear mount will have a rubber insert similar to the front mount. If you have an automatic, the rear mount is fluid filled; below 1000 rpm, the fluid is allowed to communicate to both sides of the mount to make it less stiff. Above 1000 rpm, a vacuum operated mechanism isolates the two sides of the mount to make it stiffer.

[AmTeC]

There are four engine/transmission mounts. You correctly identified the front mount (aka torque mount). There is one at the left end of the engine about even with the head, one on the top of the transmission housing on the right, and the fourth on the main cross member attached to the engine via a bracket under the intake manifold.

Is the rubber in the front mount cracked?

If you have a 5 speed, the rear mount will have a rubber insert similar to the front mount. If you have an automatic, the rear mount is fluid filled; below 1000 rpm, the fluid is allowed to communicate to both sides of the mount to make it less stiff. Above 1000 rpm, a vacuum operated mechanism isolates the two sides of the mount to make it stiffer.

The rubber doesn't seem cracked. I have an automatic transmission. What kind of fluid goes into the engine mount? Engine oil? I did mention in another thread that I've heard of cb7 hydraulic engine mounts and after I changed the oil with synthetic high mileage oil it seemed that the vibrations reduced slightly, but it may just be my imagination. A member told me It must be my imagination

[Fleetw00d]

I don't know specifically what fluid is in it - it is self contained. Only recourse is to change the mount if it is bad; I've never come up with a test to be able to determine if one is really bad or not.

[AmTeC]

Still no clear answer

So I'm still not sure how to diagnose which mount is bad, or if it even is a mount causing the vibrations. Has anyone ever devised a way to figure out which mount is bad?

[oni_cb7]

So I'm still not sure how to diagnose which mount is bad, or if it even is a mount causing the vibrations. Has anyone ever devised a way to figure out which mount is bad?

Yes, it's very easy.

Front Torque Mount: The circle flap that you pulled back in one of your pictures, lift that and look at the three pronged rubber insert. Are any of them cracked? Are there any tears? Does it look old and dry rotted?

If yes, replace the mount.


Side Mounts: these can be determined just by looking at them. Ask yourself the questions above, if yes to any, then replace the mounts.

Rear Mount: harder to do, but easiest with two people. With the hood propped and the car running and in drive, shift into reverse, then shift out of reverse. While doing this, make sure someone is watching the motor, if the rear (intake side) of the motor lifts or you can hear an audible clunk shifting into reverse, then this mount is bad and needs to be replaced.


As a note, typically the front torque mount will wear out first. If this is bad and not replaced, it will cause the rear mount to wear out as well.

Good luck