Cheap DIY urethane motor mounts

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Its been about 55 miles now, mostly highway. This is just one trip to work and back plus taking the girls to school once. Shifting feels so much better, no shudder. Leaving stops is nicer, I don't have to feather the clutch to avoid a big jolt when the engine rocks back.
 
We used to do this with Neons at the strip. You could literally 'inject' the mount with high grade silicone or urethane and fix it right on the spot, well in 8 hours or so.

Only downside is a bit more vibe than a factory mount, but on many FWD vehicles this really helps the shifting of a manual trans....
 
Good job!

Having done the Windo-Weld mount on a previous car, that was insane the level of vibration it transmitted. As in, vibrate the car like a bass drum. I wouldn't put up with it for a daily driver anymore. Good to hear that this stuff works, and is nowhere near as stiff.
 
I've done some research and found some info for different fillers, with comparative pricing.

The PL S40 I used is only Shore A 28-32, and $7.99 a tube.

3M Auto Glass Urethane Windshield Adhesive-Medium Viscosity,
PN 08693, Is Shore A 50-55 and about $15.00 a tube.


3M Windo-Weld Super Fast Urethane, PN 08609, is Shore A 55-60 and $26.00 a tube.

I think 3M 08693 is the winner, and will go in my old mounts soon.
 
I'm getting ready to do this with my Protege5. A good quality passenger side engine mount is close to $200 for the manual transaxle cars. I'm getting ready to take a weekend away. I may remove the mount and fill it with the fast curing windshield adhesive that supposedly will set in about 48 hours.

I'm glad you posted this. The jig is a good idea that I will adopt for my work.

Stay tuned over the next few weeks.
 
You can get 3M Windo-Weld Super Fast Urethane, PN 08609 on Amazon for under $19. oilBabe has Prime, so we'll see if I can get a tube shipped free.
 
Is the mount fluid filled? I guess you have very little to lose by trying a filled/solid mount but I think you'll find it too buzzy for a DD.
Some companies make urethane inserts to fill the holes in the OEM mount, I wonder if putting in an insert and then drill holes into it to soften it until you like it, would work?
 
That's the insane part about the price. It's not a fluid filled mount. Apparently the manual transmission car is sort of a unicorn when it comes to a few of the motor mounts.

I plan to try this with the easy to get to mounts first, and if it works, I'll invest the time in more difficult to reach mounts.

Originally Posted By: IndyIan
Is the mount fluid filled? I guess you have very little to lose by trying a filled/solid mount but I think you'll find it too buzzy for a DD.
Some companies make urethane inserts to fill the holes in the OEM mount, I wonder if putting in an insert and then drill holes into it to soften it until you like it, would work?
 
will be interesting to see how they hold up. Not sure if you did much to ensure bonding to the other parts (granted you used adhesives), and if it is the right stuff for the heat and everything else.

Still, nice job! I hope they last and keep us posted. OE stuff cannot be THAT different, other than how they pour/craft and cure the materials...
 
Here is my attempt for the Protégé 5

https://www.dropbox.com/sh/7j6qt4nb7x8y4zl/AACkbXZ_-ohOQ5UVmpMor48ha

I supported the engine, removed the mount. You can see the mount is completely torn. I cleaned it with brake parts cleaner and then filled it with the 3M windshield urethane. It is supposed to be fast setting. From what I've read, 48 hours should be enough. I am giving it over 72 hours while I am on a long weekend with oilBabe.

For some reason, a good quality mount for a manual transmission P5 is $150-200. So $18 in urethane and 90 minutes time is a worthy gamble to see if this works.

The other mounts are more realistically priced so if needed, I will buy replacements.
 
Of course, there are other "synthetic rubber" options that cure rather rapidly. No need to wait 4 months!

I've done similar things with engine mounts, transmission mounts, suspension bushings and yes, even pneumatic tires.

1) Polysulfide rubber sealants (for aircraft fuel tanks and for sealing the fuselage) such as PRC-Desoto PR-1422 (B2 cures in 2 hours, B-1/2 cures in 1/2 hour)
prc_pint.jpg


2) 2 part polyurethane of nearly any durometer you want (softness) I typically use 30 durometer. This stuff is cheap, easy to mix, easy to mold (such as in a paper cup) , makes great suspension bushings and so on. The pic says "RTV" which means "room temperature vulcanizing". It does not mean it's silicone sealant.

Poly74-30_pint.jpg
 
Another quick note:

The 30 durometer poly is great for various applications. One use is to fill small Chinese tires so they don't leak down overnight. Another good use is to re-fill leaking "liquid filled" engine mounts and suspension bushings. Just mix up a batch and inject it in the empty mount/bushing using the holes you drill. Works like a champ.
 
Today I picked up the 3M 08693 window urethane for $11.23 at NAPA auto parts and filled my original MT mounts. I cut a couple lengths of 1/2" aluminum tube to help fill the voids in one mount, this allowed me to complete the whole job with just one tube of urethane.







 
Today I installed the new DIY mounts. The white mounts were not pretty. The rear mount tore loose and formed a gap above the eye.





Mounted the new DIY urethane mounts and bolted the cross member in, torqued to 65ft/lbs.


Car shakes a bunch at startup, but idle is still smooth.
 
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