Write-Up: Filled Rear Motor/Transmission Mount

So the Plexiglas mold thing almost worked but not 100%


filling side


sealed side


That's the 2nd problem right there. The original rubber mold had a very thin barrier that appears to have become a tough barrier.

The first problem is I should have cut the tip off more for a larger opening and remembered to heat the stuff up a bit like Scott said. I was really breaking my hand to get it that far. I think had I addressed those two issue, this would have worked fine. I didn't have any leaking problems and otherwise, it looks like a good fill.

I guess the only thing to do now is prime it and spread the rest by hand.

Have you got that new mount in yet turtle? I'm curious what the feel inside the car is after doing this to a mount - do you get vibration mor than before?

^^^ Yes, you will feel more vibration, but it's not necessarily bad imo. At idle you'll notice more through the wheel and dash, but during driving, the shifts are actually firmer, shorter, and smoother - it doesn't jolt and becomes less noticeable than with a worn set of OEM mounts.

Codith, just fill in the gaps and you're good. Put the tube tip in the bottom of each cavity and pump it full.

I filled mine in two steps by inserting the tip of the tube into each cavity about 1/2 way down to pump out the air (there will be a bit of excess, just use a card or piece of paper to scrape it level to the top. I then waited 48 hrs, flipped it over and did the same with the other half. THere's probably a few bubbles in there, but it's better than having ALL AIR.

Oh, this stuff takes A LONG TIME TO DRY! Fill the mount about a week before you install. I'll post some pics soon.

Hmm, I havn't had a chance to look at mine yet but I'm thinking they may not be too bad. My shifts are fine, no jolting or banging, not when shifting or going into gear. I'm trying to narrow down this little vibration I get at 25k, and the symptoms described in this write sound more severe.

Mine sneaked up over time. I run a firmer shifting tune, so expected my shifts to be harder than stock. I didn't suspect the mounts were bad from feel of the shifts alone, but I knew the mounts were old and soft, and the engine makes a lot of torque. The mechanic spotted it right way with the car on the lift.

After replacing F/R mounts, I was surprised at how much more connected and solid the car feels - the "smoothness" you feel from our Buick 3800 has much to do with it's mushy mounts - it's isolation that creates some sense of that smoothness. The engine (mine anyway) isn't so smooth at idle like you might expect from a V-8 or V-12.

During acceleration, the applied torque sort of pins the engine in place and the ride and response is much less sloppy now. It's smooth torque delivery, and a really noticeable difference. And I do consider how my choice of having firm shifts and 20% more power likely contributed to wearing of the mounts!

Here's the Anchor mount (made in India) I bought from Rockauto for around $30:





I taped up the bottom side to stop any leaks:





Here's one showing the flash inside at the halfway point:





Filling half on one side at 1:20pm:



Removing excess material:





Filling the other side, finished 20 min later:





Here's a piece of excess weld, seemingly hardened, I found on the table later that night, 9:00pm. I sliced it to find it was not cured inside. It takes DAYS for this stuff to set:



Four days later, I removed the tape from bottom and filled the other half:



Extracting the old mount:







Extreme wear!



Press the new mount in to start it:



Tap in the rest:

Ok here's my rear mount


Pressing in the pucks was a little trickier with this one but doable with pictured contraption.




This won't even need the teflon tube, just a decently thick washer on each side. Hopefully it's lined up pretty good. I went a hair over a 1/4" lower than where the OEM hole is unloaded to account for the sagging under weight, which seems to increase with wear & tear. The last thing I want it to have this harder mount holding the trans up higher than the OEM one does and taking away my hood clearance.
The pucks' diameter is just a tiny bit short of filling the side-to-side space in the bracket but actually once you press it in, the pucks distort a little bit and it's about perfect. For that reason, a tighter fit top-to-bottom is better (forces the sides out more to take up the space there)

I can slice the Teflon pretty thin. If you want a set of plastic washers made, just let me know how think they need to be.

*HINT* Use thin gauge mechanics wire to poke through the Window Weld. If it's wet on the inside, it will stick to the wire. Just like baking a cake....when it comes out dry, it's cured.

AA, I just realized my last post went into the wrong thread.

Nope, it's in the right thread.

AA wrote:

I can slice the Teflon pretty thin. If you want a set of plastic washers made, just let me know how think they need to be.

One washer on each side takes up the space on the rear - shouldn't need anything more. Still need to get back to you for the fronts.

FYI, I'm leaving for vacation Fri morning, returning next Wed, so if you need these in a hurry, I'll need your measurements before then.

AA wrote:

FYI, I'm leaving for vacation Fri morning, returning next Wed, so if you need these in a hurry, I'll need your measurements before then.

We'll figure it out once you get back. I got my head in a bunch of other bs right now. I'll give you measurements for the front one and the 2nd piece just uncut so I can have it as spare.
thanks again

The pipe length and washers were dead on perfect - tight but not difficult.
That only thing that needs to be addressed using these large diameter washers right up against the bracket is the area that I have a red arrow pointing to. The casting flash line sticks out just a little bit into the area that the washer sits against on that one side. I don't think it's going to ruin anything but I will be grinding my bracket down to be perfectly flat between the trans bracket and the washer.
just FYI, that rear trans bracket is 95-98 rivs. The 99 is totally different.

AA, did you get my PM about the spacer tube?

Yes, waiting for your measurements before I cut.

Turtle,you are a mad scientist!

Thanks for the steering wheel.took a little while to get used to the smaller dia. but now I love it!

AA wrote:

You're right, Codith, that's the front mount. The listing at Rockauto says "rear", but the number 3127 is for a front mount according to Anchor Industries: http://www.showmetheparts.com/anchor/#

It shows correctly as the front mount now.

I notice Rockauto's inventory changes frequently, as do their prices and parts listing. Last week I went on to order KYB struts for our other car - they had the exact same item listed twice, one was $5 more than the other! I also notice with things like control arms, the left and right sides are often in stock at different times, and are sold for different prices. It must be difficult to update that site, with so many new parts coming through the system all the time. They are amazingly quick to ship though.

I saw albertj recommends using a primer before using the window weld. Can you find it at Autozone with the window weld or can you find it elsewhere? Is this what everyone else used or did you just scuff up the rubber before you added the window weld?

I didn't use a primer. The weld cures to a hard rubber over a few days time. If you make sure to spread a coat of weld over each end, doing one side at a time, it should stay in the voids. There's also a flash line inside the voids to give the weld something to grab. Worst case, the weld falls out and you are left with an ordinary mount.

Hey guys. I need to replace both transmission mounts front and rear. The rear more so than the front. It seems like you guys have done this without an engine lift of any kind. Is this true? MrRiviera did a write up on page 4 for the rear without one.

Can I replace both the front and rear mounts by supporting the engine from underneath? I haven't found a write up for the front mount. Is there anything else strange with these jobs I should know about?

There is more info dealing with the rear mount after page 4 (this thread).

Specifics on replacing/improving the front mount can be found here:

https://rivperformance.editboard.com/t2586-write-up-hockey-puck-casting-front-side-motor-mounts

For all other inquiries on engine mounts, see our FAQ thread:

https://rivperformance.editboard.com/t882-faq-engine-transmission-motor-mounts#9227

Hey guys,

I just ordered the rear and front transmission mounts from rock. The front one looks solid but when I opened and felt the rear mount Anchor 3065, it felt extremely flimsy and I could tell without a doubt it would be kaput in a year. I could just about dig a finger nail into it and tear it. It was also flaking black particles on my hand. Were all your guys' 3065 parts like this? It just seems flimsy and was wondering if I got one from a bad batch. Says made in India.

Anchor 3065 vs DEA 3065? Any differences?