Well everyone, my motor mounts are finally shot..
I wanted to get a set of polyurethane mounts for my SE, but I haven't been able to find any. I checked all the usual suspects and no luck. All I've found so far are solid mounts or stock replacement mounts. Do any of you have poly monts in your cars? Where can I find a set?

Tranny question: Will bad motor mounts cause grinding when shifting gears at higher rpm's? ( 5k-6k) During normal acceleration i have no problems when shifting into any gear, but at higher rpm operation, 1st to 2nd and 4th to 5th grind horribly! I know it could be a synchro issue as well, but would bad mounts intensify this?

 

well, i don't know where to get polyurethane motormouts for an rx-7, but i know you can get a liquid polyurethane, you can make your own motor mounts if you can't find any, i've also used a window sealer (i know....) for filling in crappy mounting bushings before... and on the tranny question, not sure, but i would assume mounts could be part of the problem, i think it's sync, but, if you're going to fix that, i suggest fixing tranny and engine mounts first, then see if you need to do more.

 

as for the window sealer, i can't remember what kind it was, but it worked, let me e-mail someone in our shop and i'll post what the brand is, if we still have some laying around.

 

may I ask how you know they are shot? Thanks

 

I am guessing they are shot because of the incredible amount of play in them. I can shift the motor side to side very easily with just my hands. Also when i was doing the timing on the car last week, when i hit the throttle you could see the whole motor twist, as well as the tranny. ( which does have a brand new mount by the way)

 

Anyone?

 

There is a source, They were listed in Rx tuner about 3 months ago. I will try and look for it tonight.

 

^^^ yes he is right. I forgot about this:

http://banzairacing.net/subscribers_...tor_mounts.htm

 

That is them. The price seems high to me, or is that about right?

 

i've used urethane for windows. it's working quite well actually. my mount had broke when we lifted the motor out of my car, and me being in a semi-rush to get it running, i went to advance auto (or napa) and picked up a tube of urethane. the gun to push it is no good, i just took a hammer and used my 'abs-o-steel' to push it out and fill the broken one in..

 

On your original question about the tranny mount making shifting more difficult, it is only when the tranny mount is completely gone and the engine is able to shift so much that you find yourself going from 1st to 4th on upshift, and from 4th into 1st on downshift. This is one indication that 1) you need to shift more slowly, and 2) you need to replace both engine mounts and the transmission mount!

I replaced my SE mounts with stock and think it was a good investment. The new rubber mounts will dampen out any engine vibration and cleared up an idle 'fluctuation' that I had been hunting down for about 3 months. Replaced the tranny mount with the last clutch job and was amazed at how smoothly the engine revs and idles now.

Good luck. Let us know how the poly mounts work out for you,

 

You guys are amazing! THANK YOU. As to the price of the mounts from banzai - they are $110.
Mazdatrix sells the stock mounts for i believe 59 a piece so this is not bad at all. Long Duck, I believe that the new tranny mount is the only thing that's allowing me to really shift at all rifht now. these mounts are DEAD. I still double clutch when i shift just out of habit, and that seems to be helping a bit too. Hades - thanks for the link, you rock.

 

Sorry I meant to thank Dan for the link. Hades you still rock too.