motor mount shake or wheel hop

ruswin

Registered User
I don't remember my 93 5-speed shaking when leaving the line or under slight tire slipping in the past. Now with 158,000 on it, a filling-shaking event follows almost every major acceleration. What is the deal with the motor mounts in these cars? How can I tell for sure if the motor mounts are OK? If it's not the mounts, what else?
 
Shocks

Ruswin,
It's probably the rear shocks are weak. Have they been changed? Have a friend watch for wheel hop when you burn out. I recently ditched the "active ride" (Read="expensive and unnecessary") shocks with regular old Monroes. Just don't tell the counterman it is an SC. They will tell you the shocks won't fit. They will physically fit in there, but you will lose the gimmicky gizmos that adjust the damping. I left the actuators in their stock locations, connected, with no problems.
My only gripe is that a car with this kind of weight and power needs a shock that is more firm than the Monroes. I think KYB makes manual adjustables that will fit with a bit of fiddling up front. There are Bilsteins and Koni's that are stiffer than the cushy Monroes, but prices are close or equal to the stock electronic ones.
I always left my car on "firm", so I saw no reason to have this system clicking in and out.
I no longer have problems with wheel hop though. I am still considering getting the KYB's to firm up the feel.

As for the motor mount, get under there and get a look at them. Usually, it's the driver's side that breaks. You will have to look in from the rear of the motor to see it. If the metal stop tab is resting on the metal cage, it has collapsed and is probably broken like mine was. You will need to take out the I/C tubes, alternator/steering pump bracket (leave the alt and pump on the bracket, it can be done!) and probably the steering coupler to get the thing out, but it WILL come out with less trouble than meets the eye.

Best thing is, that is probably not your underlying problem. Rear shocks are easy. Motor mounts aren't!

I felt my mount give when letting out the clutch. There was a weird "rubbery" feeling to the engagement. That was the motor lifting up.. Though if you have an automatic you might not notice that much.

Good luck!
Scott
 
On your motor mount.I f the oil filter hit the lines when removing or hard
to get off after unscrewing it,you need motor mounts.

I f the oil pan set a little below the k-member you need motor mount.

If you put a block of wood under the oil pan and jack it up about 1/2 to
3/4 of an inch.and you then see a gap between the motor mount,you
need new motor mount.
 
Signs of bad motor mounts

Thanks for the good feedback. Unfortunately, it is the motor mounts. Doesn't look like a very fun job. Does anyone know what a decent price to have them installed is? I attached a picture which should help people ID the motor mount failure signs WITHOUT having to jack up the engine. Just look at the oil pan and or the oil filter. My oil pan is a full 3/4" BELOW the crossmember and the oil filter sits 1/2 way down the crossmember. I drove it for about 50 miles with a serious vibration in order toget it home. Could I have done any other damage?

I hope the pics help.
 

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You can ware a hole in the oil pan if you let it go long enough.
And you can ware into the power steering line by the oil filter to.

When I replaced my motor mount.I removed the both accessory
brackets.

On driver side,under the car you will need to take one bolt out of steering.

On both motor mounts, part of the job will be done from the top,and some
work under the sc on both sides.So you will need jack stands.

You will need a peice of wood to put under the oil pan .So you can jack motor up
to get old mount out .and you may need to jack the motor a little higher up,to
get the new mounts in.

You may need to remove the plastic cowl and wind sheild wipers.So you
will have enough room,when jacking the motor up you don't brake the plastic cowl.

While you have the plastic cowl off under the windsheild.Get some 3/8in or
1/2 inch hose clamps.And put a hose clamp on every vacumm line you see.
Put plastic ties on the vacumm lines with the small nippled ends.The vacumm lines
on the intake manifold intake plenum. Doing this will save you time later. If you
should ever develop a miss in the motor or what ever.clamping the vac lines
will give you a peice of mind that the lines on the back of the blower area
are not leaking .cost about $1.50.
 
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Search the forum for "motor mounts" and you will find at least 3 different methods for replacing them. Shops with a lift will do it an easier way than most of us and drop the entire front subframe to get at the mounts.

Shouldn't be more than a $500 job, not including parts. Though a dealer could push it to $750. Depends on the labor rates in your area. Figure 5 hours.
 
Thanks people... I'm not opposed to doing the job but I live in Arizona and a 5+ hour job in 100'F heat, plus frustration is not worth it. I'm probably going to print out a couple tidbits from this website and give it to someone with the proper tools. I'm en electrician... not a mechanic.
 
I beleive with broken motor mounts.That when the motor gets to jumpin around.
The vibrations will set off your knock sensor and pull some timing out.
So when you get them fix.You may see some more power and maybe
some better fuel mileage.

Good luck RANDY
 
Unrelated question but how much boost should I get from my stock 93? I just checked the supercharger oil level and it is low... It makes more mechanical noise than my 95 parked next to it and it onlt gets up to about 8 PSI under WOT. What damage could I have done by running it with low oil? What is the normal lifetime between overhauls to the supercharger? If I have to get the thing rebuilt, is there anything alse I should do to it at the same time?
Ooops... got a little carried away!
 
Suggestion

buy solid rubber ones so you wont have top worry about breaking them for a long time....my brother about 7k miles ago replace one of my motor mounts when we had my engine out and where checking the main bearings and now 7k later i just did alot of replaceing on my driveline and i noticed i had a shake in my motor and shifter real bad, and i replaced the tranny mount with a solid rubber one also before so i didnt know what was wrong.. come to find out when we just took my driveline all apart again i bought the solid rubber motor mounts because SuperCoupePerformance recommends them with the Spec clutches, because i just bought the Spec Stage III Clutch kit/lightned pressure plate/Spec Aluminum Flywheel/Inland Empire Aluminum driveshaft, got my tranny rebuilt ...So we took my motor mounts out and 1 that was the old one came out in 2 pieces and the one that was newer was almost in 2 peices..and also i spoke with Bill at SuperCoupePerformance and he said the stock motor mounts are known to go at any time..but he said he doesnt know anyone yet to break the solid rubber ones..and it takes a bit to replace them so i'd go with solid rubber and not worry about it for a long long time..
 
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