Polyurethane Engine mounts Help

[GTOLou]

I put in prothane mounts a few months ago - when I added a BP crate and I had to swap the urathane/mounts from one side to another. Like there was a "left" and "right" side. One of the little metal barbs that stuck out would only line up on one side. Not sure that'll help, but it kept me from getting mine in.

 

[jthomas]

I had the same problem as you. They look like they will never line up but they will. Persistence gets the prize!

Lube the urethane mounts before installing them in the clamshells. Use silicone grease. Then I loosened the motor mount to frame bolts and then used long heavy flat end screwdrivers to pry the urethane portion of the mounts toward the top side of each clamshell. I lowered the engine and placed a Phillips head screwdriver that had a shaft about half the size of the motor mount bolt in one side and used the engine hoist to lift and lower the block just enough to get another similar screwdriver in the other mount. This part took a while. Once both mounts had screwdrivers in them I took the pressure off the hoist and let engine rest on mounts. I used the screwdrivers to pry the engine as centered to the mounts as I could. I then pulled one screwdriver and used a silicone greased motor mount bolt into the hole and pounded it through with a hammer. Then I used the hoist to lift that side with just enough pressure the let the other side some room to drop. Lube other bolt and hammer in. The flat end screwdrivers now come out. Now unhook hoist. Lastly, tighten the mounts to the frame (The biggest PITA of all when the suspension is in place but it is also doable.)

It’s a huge PITA but they will fit. Once they are in, the motor doesn’t move much if at all.

 

[need-for-speed]

Are you using clam shell mounts with one mounting hole in the center/bottom instead of three corner holes?

IF so... Those are the wrong mounts.

They should mount like this:

View attachment 143593



I battled for hours trying to get the "performance" mounts to work and it wasn't possible.
Use this style.
(Four mounting holes in the corners but you only use three of them.

https://www.autozone.com/external-engine/motor-mount/p/mrc-mounts-front-driver-or-passenger-motor-mount-a2292/1011780_0_0

If you want to use the poly inserts, open them up and replace the inserts.

I see you put the bolt heads on top.
That's "factory correct" but it's a lot easier to pull the bolts up through the frame and put nuts and lock washers on top.
An impact wrench will usually tighten them without the need to put a wrench inside the frame.

Good Luck!!!

Thanks for the tip on the bolts! I remember replacing mine in 1992 while the engine was in. It was a bitch. I used a crows foot and turned that nut (or maybe it was the bolt?) one flat /bite at a time! I plan to replace them again when I pull the motor in a couple of weeks. I’ll follow your advice and go with the upside down approach!

 

[Twisted_Metal]

Thanks for the tip on the bolts! I remember replacing mine in 1992 while the engine was in. It was a bitch. I used a crows foot and turned that nut (or maybe it was the bolt?) one flat /bite at a time! I plan to replace them again when I pull the motor in a couple of weeks. I’ll follow your advice and go with the upside down approach!

A piece of craft/floral wire fits in to the bolt threads perfectly to use to pull them up through the frame.

Some people use fish line but the wire worked great for me.

 

[BonzoHansen]

I had these same issues. Alignment dowel tools helped, as did a big pry bar. But I don't remember what was the magic spot was, but it took a long time to find it. So frustrating.