motor mounts

bholmes · bholmes's Garage

any tips or words of wisdom on motor mounts. I'm pretty certain mine are shot. I checked my balance shaft alignment when it started vibrating so bad, but it wasn't the problem. It vibrates awful at idle and still vibrates through the rpm range. I used the old SoCal method of checking the clearance between the oil pan and crossmember with your hand and according to this I need new motor mounts. So how's the easiest way to do this and where are the cheapest mounts from? So far it looks to me like pelican is the best deal, which makes me happy. I have read you have to pull the crossmember to change them, is that a nessecity or can I do it with out doing that. I just want to simplify things if I can. Thanks for the help.

Techno Duck · Techno Duck's Garage

Yes, you have to take the cross-member out. Its not hard to do, but labor intensive. You need to remove the control arms and the steering rack. You also will need to support the engine above, which can be done with a few cut to length 2x4's, chain, hooks and a 4-5 ft piece of super strut from Home Depot. Clarks-Garage has a procedure that does not involve removing the steering rack and control arms..but honestly i think its more trouble than its worth. Thats just my two cents.

If you do a search about motor mounts, you will see the non OEM ones typically fail very early.. the consensus is the Porsche OEM mounts are the only way to go. Yes they are more expensive, but you save money by not having to redo it in the long run.

bholmes · bholmes's Garage

how much difference in life expectancy. I'll research it more when I get a chance, i'm just being lazy. If the aftermarket will last me around two years or so it's no deal to me, but if they fail with in the same year that's a problem. Thanks for the tip. Sounds like i'll be pulling the cross member to do it. Thanks for the input.

eviladam · 08-07-2007, 06:44 PM

i did mine in about 4 hours(first time i worked on the car, 3rd day i had it) i took the cross member out but i did not remove the steering rack or the control arms. i found the job to be very easy just a PITA to get it mounts bolted to the motor due to space. i held the motor in place from the top and everything worked out great, i didnt even cut my knuckles!

edit: i used the cheapo mounts and i DO NOT drive this car lightly, going on 1 1/2 years with them and no problems.

bholmes · bholmes's Garage

Sounds not to bad on the cheap mounts...where did you get yours? It really doesn't sound to bad, I just like to have an over view of my job and tips from the pelicanites before i get into it. I hate it when I do a job then one of the guys tells me a much easier way.

ERAU944 · ERAU944's Garage

i also didn't remove control arms and/or steering rack. what WILL help you is to remove the front sway bar for when you drop the crossmember. undo the sway bar, support the motor, unbolt the motor mounts, take out the four bolts and pull down the cross member, remove the old/worn mounts, install the new, then reverse everything back together.

a moment to read, a few hours to execute, thousands of miles to enjoy!

bholmes · bholmes's Garage

You make it sound fun! I am thinking about putting new sway bar bushing on when I do the job. You don't have any 30mm front sway bars do you mike? PM me if you have one.

JustinL · 08-08-2007, 07:56 AM

I'm running one solid engine mount on the exhaust side. I don't notice any excessive shaking or vibration. It was cheaper and will last forever. When the driver's side mount goes (which should be a long time not being subjected to the heat of the exhaust) I'll put the other solid on that side and a solid tranny mount.

bholmes · bholmes's Garage

where did you get the solid mounts? I like the sounds of that. I used solid mounts on my chevy for years, it vibrated a little more, but not bad...may have not been balanced the best though. Just for the record, not sure if it's the same for these cars, but on the chevy if you used solid tranny mount you had to have solid motor mounts so the rocking of the engine didn't snap the bell housing. Just thought i'd throw that out there, not sure if it's pertainat to our cars or not, but you never know.

JustinL · 08-09-2007, 06:32 AM

Same thing with our cars. That's why I only did one side. There is still some movement that comes from the other mount. I bought my solid mounts from lindsey racing. They are cheaper than any other style. Also check out some of their more expensive mounts too.

flash968 · 08-09-2007, 09:09 AM

i've gone through this on a number of other cars - on my charger i actually had to add a chain to prevent the engine from crashing through the hood when the mounts broke - lol - but then a supercharged 440 will do that

i'm playing with this right now on my 968 - my engine puts out enough torque to actually watch the motor jump up about 1/8" on throttle - the OEM mounts are in excellent condition, but just allow too much lift - i tried a polyurethane centered mount, on the driver side only, and got WAY too much vibration - i am now designing new mounts with rubber centers to resolve this problem

bholmes · bholmes's Garage

supercharged 440....that sounds nice. One of my buddies has a N/A 340 that makes 478hp at the flywheel on the dyno. It's in a 69 dart, it's a fun little car.

How much more vibration did you get from the poly centered motor mounts Flash?

Justin, did you notice a big difference in your solid motor mount?

I can stand some vibration, but excessive. Of course it's excessive now. It's better than bad mounts certainly...right?

JustinL · 08-09-2007, 11:25 AM

It's better than a collapsed mount, but I changed so much stuff when I did the mount that it's hard to say what did what. With the new engine and exhaust resonater, it will vibrate at idle, but not so much that I can't stand it. My girlfriend doesn't complain about it. It doesn't vibrate the mirrors or any of the interior parts, but you can tell the engine is running.

bholmes · bholmes's Garage

Sounds liveable. It's hard choosing between raw performance and smooth opporation. My car has never been 100% vibration free. I think one engine mount was bad when I got it and the other went just recently. What does the tranny mount do when it goes bad? When I go around a curve I can feel my shifter sway, is that the mount back there? Anyone know of a rubber tranny mount that doesn't cost over 150 bucks?

flash968 · 08-09-2007, 04:36 PM

vibrated enough that i yanked it back out immediately - i know i can do better - i shoudl have a prototype in about 2 weeks

yes the blown 440 was nice - 650 at the wheels - silly fast - even with the nutty suspension though, you still had to watch what you were doing - nobody should have a car that big that goes over 200 - i wrecked it in spectacular fashion, spreading it over a half mile of road

bholmes · bholmes's Garage

Glad that you lived to tell about it. Got any pictures of the machine? I love old mopars. I have a 383bb that I intend to build for a t-bucket that is on the back back back burner.

bholmes · bholmes's Garage

Oh, and in regaurds to the tranny mount. Any tips or experience there?

flash968 · 08-09-2007, 06:49 PM

charger wreck - imagine the tin foil after you pulled it off a bake potato

tranny mount - not been a issue, other than the side loading and resultant shifting - the new motor mounts should resolve that too though

bholmes · bholmes's Garage

Replaced the motor mounts today, it's much much much better. I used the 951 aftermarket replacements. It wasn't to bad of a job. Now I need to see if I can silver solder that fuel rail so it'll last untill my new one gets here!