I am thinking about reinforcing the new subframe bushings I have for my 90 325i, before installation.
I want to fill in the gaps to reduce deflection under load. Pic below.
This should hopefully keep things fairly quiet (compared to full urethane), yet still improve rigidity of the rear subframe.
Is urethane available in some kind of two part mix? Can this be found locally?
Easiest way is to go to Carquest or NAPA and purchase 3M superfast urethane for windshields. It is 1 part and comes in a caulk tube. Make sure you wear gloves when you do it.
Excellent, thanks alot.
Still looking for help in your shop?
its called window weld BTW advanced auto has it
This is what’s used to secure/seal a windshield?
Thanks
used it in my motor mounts, that shit works great.
You can get it in a caulk sized tube and use a caulk gun.
oh, and buy a bondo spreader thingy too.
tape off 1 side, and fill the mount slowly. then smooth it out with the spreader. it will take a day or 2 to set up.
Document how you did it then you can post it in the DIY section.
:word:
I did this when I replaced my transmission, the car shakes like hell now, I love it.
Thats a damn good idea. Urethane is sticky shit. that gets very firm. WEAR GLOVES
yea, no doubt. i ruined my favorite ugly shirt thinking i could be careful with the shit. it is messy, and gets all over.
Thanks for moving the thread.
I bought the 3m win-weld stuff, and filled in the mounts.
Thanks for suggesting the gloves! I used some, but still managed to get some on my hand, it doesn’t come off!
I didn’t use the spreader, didn’t see that comment until now. I just used my finger. Not as smooth as I would like. But should serve it’s purpose.
I’ll post pics shortly.
Thanks
I wish I had been on here a few days earlier to give you these “critical” tips for working with this stuff as I’ve filled several mounts including all of mine now with it.
You’ll notice the stuff is extremely sticky… sticks to anything, can’t get it off. You’ll be puzzeled then as to how to effectivly smooth it… you said you used your finger… that’s not bad BUT… there is ONE thing that works well.
ICE.
Sound weird? I know, it is weird. But think about it. It can’t stick to it, because it’s melting as it’s trying to stick to it. And water has no effect on the stuff. Just take an ice cube and use it to smooth it while it’s still wet and it’ll come out pimp.
Secondly… you can check the drying of the stuff just like you check cake… Stick a needle in it. The depth that has “black stuff” on it still, is the depth it’s still drying at. Expect it to take AT LEAST 1 full day to dry, but ussualy more. One mount I did, it took 2 and a half days for the needle to come out clean…
Thanks for the tips, a little late, but I’ll keep it in mind. Here are some pics.
Not too smooth, but it will be well out of sight, I should have used ICE!
You guys realize that there isnt just one type of urethane. There are dozens of formulations with different elasticities. I doubt that shit is anywhere close to what bushings are made of. Looking at the pic of the bushing you posted it looks like its only designed to deflect in 1 plane… up and down from the picture.
being that its a suspension crossmebmer bushing, im sure the busshing stands upright when installed, and most of the forces it will see are lateral loads, just like most most front engine mounts on fwd cars
while windsheild urethane isnt the stiffest stuff you can get, its still better then airgap, and its pretty well documented on forums across the internet that WS urethane does a nice job of stiffening up bushings. obviously the more airgap there is in the bushing, the more effect the urethane will have
I have read about aftermarket urethane bushings eventually deforming the part they are in due to the lack of lubrication.
This type of bushing modification almost seems to be better than buying new aftermarket replacement bushings.
It’s very similar to the density of aftermarket bushings. A little more flexible and less stiff, but that’s part of why it’s such a good choice, because it stays flexible and it’s super sticky during application, which means it ussualy never works itself free of the bushing.
It’s certainly a better choice then sticking dowel rod in the bushing which is still what I see a lot of people doing.