Symptoms of a bad motor mount

Donkeypuncher · Post by **Donkeypuncher** » Tue Nov 22, 2011 2:11 am

Not the torque struts, but the actual motor mount or center mount. Been trying to track down the culprit of my horrible vibration problem without any luck. Thought it was an exhaust leak at first and replaced the manifold with an obx lth. Then I replaced both axles, upper and lower torque struts, and the transmission mount. None of that fixed it.

Symptoms:

- When revving the engine, from 1800 to 3k rpms it vibrates the entire dash and I can feel it through the steering wheel and all the pedals.
- The vibration gets deeper and louder when I hit dips or bumps in the road. It does this at any rpm 2k+, but seems worse at the lower rpms
- It doesn't do it when coasting in neutral over dips/bumps
- It does do it in neutral with the rpms 2k+ over dips/bumps
- Sometimes it doesn't do it in reverse, sometimes it does

I thought it was a leak at the collector on the header, but I've replaced that. It seemed a little better when I overtightened those 3 botls, but came right back after a few minutes. Just want to make sure I didn't miss anything before I go and replace the motor mount since that is gonna be a pain in the ass.

Notanexit92 · Post by **Notanexit92** » Tue Nov 22, 2011 10:18 am

I know my center motor motor mount is shot as well, I can take a flat head and see cracks all around it. I think if your Torque Struts are in good shape, and actually aligned, it'll be okay, I'm gonna replace my motor mount when I change the timing belt soon. You sure your not running open header?

I'm running Open header with my OBX and it vibrates the shit out of my car.

gilly02le · Post by **gilly02le** » Tue Nov 22, 2011 11:24 am

my obx lth makes my car shake too, especially with solid motor mounts.. i attribute it to the fact that the header has no flex pipe.

Hudson_Neon · Post by **Hudson_Neon** » Tue Nov 22, 2011 12:02 pm

make sure there's nothing touching the car. mine sounded like that when the fitment of my downpipe wasn't perfect after installing my turbo at carlisle.

also, try reving up the engine at the throttle body and watching it. take a jack and a board and jack up the engine on the oil pan and watch to see how much it moves up and down

g_force58 · Post by **g_force58** » Tue Nov 22, 2011 12:43 pm

since you put on a LTH, wouldn't that weigh the engine toward the back of the car/ Wouldn't the vibration from the engine cause a resonance thru the header due to the extended length and cause more vibration? I don't know since I have no experience with the LTH, but it would seem to make sense. Just my 2 cents.

Hudson_Neon · Post by **Hudson_Neon** » Tue Nov 22, 2011 1:49 pm

a LTH doesn't weigh enough to put that much more stress on the mount.

Donkeypuncher · Post by **Donkeypuncher** » Tue Nov 22, 2011 5:47 pm

The header and exhaust have plenty of clearance, that was the first thing I checked. There isn't any movement revving at the TB, I'll try jacking it. I thought maybe the lack of flex pipe might be the culprit, but it was doing this when I had the stock exhaust manifold on there as well.

I really started to notice it a few months after doing my timing belt and prothane inserts on the trans mount/torque struts. I can also hear a faint clunking sound in gear at low rpms when hitting little washboard bumps in the road or running over city titties. I thought it was the LCA bushing, but it doesn't do it when coasting in neutral.

It's not unbearable, just really annoying. I'll try and get a video inside the car and see if the camera can pick up the noises.

darthroush · Post by **darthroush** » Thu Nov 24, 2011 2:32 am

A bad motor mount will cause a noisy hell in the car, especially when accelerating and while the car [suspension] is "loaded" as it goes over a bump/hill in the road. It subsequently gets quieter as the car passes said bump/hill.

Donkeypuncher · Post by **Donkeypuncher** » Thu Nov 24, 2011 6:07 am

Yup, that would describe exactly what it's doing. Sounds like a war zone inside the car when I take off in 1st gear. The only time I don't get any vibrations is at idle, which is kind of ironic.

Post by **occasional demons** » Thu Nov 24, 2011 9:43 am

You are not loading it at idle, other than the weight of the engine. (Unless it is an ATX in gear)

Donkeypuncher · Post by **Donkeypuncher** » Thu Dec 01, 2011 11:56 am

::UPDATE::

Looks like the motor mount was the problem, the rubber is cracked and separated from the metal.

I also noticed some liquid dripping out, didn't know the mtx has a fluid filled mount. You can see where it's leaking out of the cracked rubber.

Picked up the mount from napa, didn't want to take a chance on the anchor brand after hearing bad reviews. The napa one appears to have a lot more rubber in there.

About to put it all back together and see how it feels. I hope that's the last thing I have to replace for a while.

darthroush · Post by **darthroush** » Thu Dec 01, 2011 3:11 pm

A fluid-filled OEM motor mount. I'm curious how the NAPA one will fare. NAPA wanted to sell me the Anchor one when I went in (and I only bought it elsewhere due to the price).

Donkeypuncher · Post by **Donkeypuncher** » Thu Dec 01, 2011 5:12 pm

Well, the motor mount was definitely the problem. The car feels so much nicer, almost like it's brand new. All of the vibration is gone as well as the clunking noises. I'm so relieved right now, it's been 2 years of hell trying to figure out the problem. We'll see how well the napa mount holds up, haven't heard any bad things about their product line.

Thanks for the help guys

sidepipe87 · Post by **sidepipe87** » Thu Dec 01, 2011 11:02 pm

Soooo how much hell did you go through installing this? When we did the T belt last year the tech that works next to my dad suggested we replace it because they go bad and I thought "nah... it'll be ok" plus I didn't have the money after all the parts and labor for the T belt/water pump/tensioner/LCA bushings/inspection

Post by **occasional demons** » Thu Dec 01, 2011 11:12 pm

Either remove the motor mount plate or all the torque struts/mounts, and slide the engine/trans assembly to the driver's side. Either way sucks.

Donkeypuncher · Post by **Donkeypuncher** » Fri Dec 02, 2011 2:31 am

I ended up dropping the trans side with a 2nd jack and sliding the the engine over a few inches. With the mount plate off and those few extra inches there is enough room to get at the bolts. It wasn't fun, but at least I didn't have to do the timing belt.

I forgot about the lower coolant hose when I was jacking up the engine, so of course it popped off and shot coolant everywhere. Now I remember why this was one of the last parts on my list, wish I did it during the timing belt.

Post by **occasional demons** » Fri Dec 02, 2011 7:25 am

Yep, that is how I did mine, tho only because I was changing the MTX mount at the same time.

Donkeypuncher · Post by **Donkeypuncher** » Fri Dec 02, 2011 7:54 am

Same here, I switched back to my old trans mount with inserts since I already had it all apart. The crank pulley will hit the mount snub when jacking up for that 3rd mount plate bolt unless you drop the trans or remove the crank pulley. I didn't have a puller, so I got to do it the fun way.

XxWhiteNeonxX · Post by **XxWhiteNeonxX** » Fri Dec 02, 2011 1:09 pm

you should get ahold of some 3m window urathane, and fill that mount while its out of the car. Really helps with the motor wanting to sag down.

Public Disturbance · Post by **Public Disturbance** » Sat Dec 03, 2011 11:00 pm

occasional demons wrote:You are not loading it at idle, other than the weight of the engine. (Unless it is an ATX in gear)

This could be my problem D car shakes like a mofo N nothing is there a how to on how to intall motor mounts and what are the torque struts everyone is talking about I thought is was just the two motor mounts and the tranny mount I would search but I'm on my blackberry and its a pain

Post by **occasional demons** » Sat Dec 03, 2011 11:20 pm

The TS's are the two bars top and bottom on the passenger side. The motor support mount is between them in the side rail of the body. It attaches to the aluminum plate that the upper TS is bolted to.

Public Disturbance · Post by **Public Disturbance** » Sun Dec 04, 2011 12:49 am

So the solid motor mount people get are actually the torque struts? and the aluminum plate is the engine support mount?

brybry · Post by **brybry** » Sun Dec 04, 2011 2:57 am

Donkeypuncher wrote:Not the torque struts, but the actual motor mount or center mount. Been trying to track down the culprit of my horrible vibration problem without any luck. Thought it was an exhaust leak at first and replaced the manifold with an obx lth. Then I replaced both axles, upper and lower torque struts, and the transmission mount. None of that fixed it.

.

Even with the new engine I just got, it still vibrated a lot. I was thinking the same thing this guys was thinking. A had some thoughts that it could be the motor mount but I wasn't sure, since I saw my CV axe boot toured.

This thread really helped my problem.

next paycheck I'm gonna try to get this fixed!! thanks you guys

Post by **occasional demons** » Sun Dec 04, 2011 12:02 pm

Public Disturbance wrote:So the solid motor mount people get are actually the torque struts? and the aluminum plate is the engine support mount?

The aluminum mount plate is what the mount pictured above is bolted to. In the center. Yeah most times "solid mounts" is in reference to the torque struts. It is just one of those terms that isn't correct, but has stuck.

Public Disturbance · Post by **Public Disturbance** » Sun Dec 04, 2011 6:25 pm

Yep quick trip to my friend at autozone cleared it all up and now I can say I learned something new today lol so would it be a good idea to replace the mount when I do my dogbones to and like was said fill it with the window epoxy going to leave the stock transaxle mount in there till I do my mtx swap and then doing a solid trans mount

Donkeypuncher · Post by **Donkeypuncher** » Mon Dec 05, 2011 1:39 pm

I guess you could fill it with epoxy, not sure if it's worth it though. The napa mount didn't have any empty space to add epoxy anyway. I'd wait until you do the mtx swap, with the trans out you could probably move the engine over enough to get at the mount without removing the mounting bracket.

Public Disturbance · Post by **Public Disturbance** » Mon Dec 05, 2011 3:42 pm

Donkeypuncher wrote:I guess you could fill it with epoxy, not sure if it's worth it though. The napa mount didn't have any empty space to add epoxy anyway. I'd wait until you do the mtx swap, with the trans out you could probably move the engine over enough to get at the mount without removing the mounting bracket.

Yeah that is what I was going to do that way I can throw in the solid tranny mount all at the same time

chipdogg · Post by **chipdogg** » Mon Dec 05, 2011 9:13 pm

You guys that are dropping whole thing and moving to passenger side, those are 5-speeds, right?

I tried it with an auto today and there's no way in hell I could get it to move anywhere near enough to get mount out of frame.

Even had the trans mount unbolted (some jackass decided to put the shifter cable through it so it stayed in car). Trans hits frame, k-member, etc.

Ended up pulling off the motor mount bracket and almost had enough room to get mount out till the jack slipped out from under oil pan, dropped engine, gashed my thumb open, and destroyed outer timing cover. Came out relatively easy after that.

All in all it took 1.5 hours to drive car over to front of garage, finagle engine hoist out blocked door, find out there's nothing to grab onto with everything installed, jacked up car, removed tires. Dropped entire engine/trans down, tried moving over, reinstalled trans mount. Pulled ps pump and side plate, got mount most of way out, busted shit up. Replaced mount. Pulled bracket and belts off spare '04 engine, crank pulley, and timing cover. Pulled crank pulley and replaced timing cover on '03. Re-assembled and drove it around.

Much better now, 178k on original mounts. New owner appreciates the new mounts lol.

If I wasn't retarded, I woulda replaced the damn thing when I had waterpump out and head off. Bet it woulda been easier to do then.

Post by **occasional demons** » Mon Dec 05, 2011 10:14 pm

Yep, mine is an MTX.

Definitely needed to drop the trans end to clear the frame rail. I guess the ATX is physically larger where it hits, and won't let it drop enough. Sucks.

The half shafts weren't an issue; they had enough play to let it move over. If I wasn't doing the MTX mount at the same time, I would have done it the FSM way. (Pulling motor mount bracket) I did it on an uneven asphalt parking lot. Very intense with only the exhaust to keep the assy stable, and two jacks to position it, like pictured above.

chipdogg · Post by **chipdogg** » Mon Dec 05, 2011 10:21 pm

Yeah that trick definitely didn't work with an atx. Axles weren't the problem, the huge size of it is though. The mtx is like half the size on the side.

Pulling plate still sucks, not sure how you gotta finagle the engine to get it out but busting the shit out of the timing cover made it much easier to remove that's for sure. Now I'm short a SOHC outer timing cover for the spare engine. And it's partially torn apart now. Lame.

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Symptoms of a bad motor mount

Symptoms of a bad motor mount

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