new rear motor mount but still vibration

[kemetuimay]

Hi
i have a 91 accord coupe automatic

when i first got the car there is a vibration at all time then i read through this website and found the similar problems and found out that i needed to change the rear motor mount, check the dist timing, and vacuum leak

well i done all those things and my car is still vibrating when i come to a red light or stop sign, after i change a new motor mount the only thing that got better is the idling when it is at park which mean i only get vibration when im at a red light

Can anybody tell me any other way i can fix this problem when a new motor mount didn't solve the vibration problem

I tuned it up with everything new like new spark plugs, new gaskets, new dist cap and the chip, new motor mount from front to rear

it will great if you guys can help me out because i have been fixing this car for more than a year now and no improvement

[boostdelinquent]

Have you checked the inserts for the other motor mounts? This may sound unlikely but how long has it been since the fuel filter was changed? I know on semi's once they start to go, it can cause a shudder/vibration so that could be a potential cause as well.

[kemetuimay]

thanks for replying
but yeh i did all the tune up including the fuel filter too but still no luck

[JSMexUsa]

I have lots of shaking while at red lights; I replaced the front motor mount with one from ebay for $25 (honda wanted $100) and didn't fix anything, probably the cheap motor mount is too soft and/or need to replace the rear one as well but mechanic told me is a lot of work and money to replace the rear one.

How much did you pay to replace the rear one and did you buy the Honda one?

[dadsCB7]

i replaced all mine with ebay ones and the vibration was worse than when the old mounts were in. the old driver's side mount was still ok, so i put it back in and a lot of my vibration went away. ebay mounts ftmfl...

[kemetuimay]

yeh i bought mine from ebay too and i replace it myself
its not that bad to replace it yourself, the only thing i hate about it is i have to drain the radiator out and put new gasket in everytime i try to check on it

but same here i think its a little worse with the ebay mount, the only think i remember is that my car vibrate while in park and drive with the old mount then this new mount only help cut back half of the problem, which vibrate only when i come to a red light

[K2e2vin]

Well, if it idles well in park, but vibrates in Drive, then I'd assume it's something with the transmission. Try getting a flush along with the tune-up.

New motor mounts would just transmit more vibration than before; assuming the old mounts were still "floating"(as in no direct metal to metal contact that would transmit vibration).

My sister's 94 Accord does this btw, I just pop it in N at red lights.

[kemetuimay]

i have thought of flushing my transmission before but one problem is the car is old and i don't know if the old owner ever change the fluid ever and i heard that i shouldn't change the fluid if the car is over 100,000 mile and never got the trans changed

[JSMexUsa]

i have thought of flushing my transmission before but one problem is the car is old and i don't know if the old owner ever change the fluid ever and i heard that i shouldn't change the fluid if the car is over 100,000 mile and never got the trans changed

That,s BS; You have to change all fluids, do full tune up and timing and all belts whenever you buy a used car because most sellers sell them before doing major maintenance or repairs.
I change my transmission fluid once a year or at 15,000 to 20,000 miles.

[wed3k]

here's the thing, if you tighten the motor mount and the engine is cocked at an angle, it wont allow th rest oof the mounts to absorb the vibration.

you need to put the engine's weight on a jack and then tighten all the mounts. otherwise, the mounts will bind. the same applies to control arm bushings. you need to have the vehicle in a rested state and not jacked in the air.

[K2e2vin]

That would mean you'd let the motor hang before torquing it down.

[wed3k]

That would mean you'd let the motor hang before torquing it down.

actually on a jack...it would be at rest since the weight is on the jack and not on the mounts.

you want all the bolts to thread in by hand.

[K2e2vin]

Do you realize what you're saying?

For LCAs, you'd lower the car onto it's wheels and tighten the bushings then; therefore the resting position is with the bushings in the "neutral" state.

Same with the motor mounts; if you have it on the jack, tighten it, then drop the jack, then it would be twisting the mounts in the engine's "rested" position.

I agree you want to bolts to go in by hand; but once you get it in, drop the jack, and then torque them down.

[wed3k]

my statement still stands corrected.

because if the engine is already putting pressure on the bottom of the engine mount, what if the engine wants to rock backwards on the rear mount? there will be no room or play for the bushing to move. thus it will bind and transfer the movement to the frame.

[K2e2vin]

It still has room to move. If you ever looked at the webbing of the mounts, they're designed to "hold up weight".

If anything, tightening it on a jack would more likely cause it to bind since it's actually going to pull the mount down when you tighten it("preloading" the bushing you could say). The mounts will be trying to keep it in the same position as when the motor is jacked up. Tightening it on a jack is like tighten the LCA with the wheel still raised up.

BTW, IMO I assume it's not that important whether or not the mounts should be torqued on a jack or not; I'm arguing behind the logic of your statement. I personally like it hang from the mounts and then torque them down. I've never had an issue in any of my cars.