buick engine mounts

Did the welds crack? That is some beefy steel to stretch like that to allow the parent steel to bend.

 

The welds didn't crack. The plate just stretched between the bolt holes. I put the caliper on the plate and it measures 3/16 with the paint. Under normal circumstances you might not even notice them stretching that much, but I had minimal clearance on my front crossmember with the fan to begin with. So, a little drop at the mounts equated to quite a bit at the front of the engine. Just to clarify, the mounts I have the pics of were bent because the Jeep went over a retaining wall and dropped about 30". But that's a story for another thread. One that I'm not ready to 'fess up to yet. Anyway, it was the replacements for those mounts that tweaked just from running a fairly mild trail. I couldn't do pics 'cuz they were already installed. I think the plates on the older ones are thicker. The new replacement ones I just received are not as heavy duty as the older ones I had originally ordered in 2005. All that said, the damage to the new mounts was identical to the damage in the pics, just no way should have happened on the trail I was on, barely more than a logging road. I'll try to mike the plates on both mounts and see what the real difference is. Raining here right now with snow possibly tonight.

 

Welding the mount to the frame should solve the problem.

 

It's not the frame mounts that are the problem They are welded to the frame. It's the plates that bolt to the engine block that are sprung.

 

John,
I'm thinking about the forces that would cause the plates bolted to the side of the engine block to spring like that. Seems to me that there may be a lot of frame flex going on, with each frame side rail moving fore and aft with respect to the other side (diamond distortion of the frame). If it were mine, I would be looking at how firmly the frame crossmembers are attached to the frame rails, are all the rivets still tight? I don't remember seeing on your Jeep whether you still have the original front crossmember or not, if it's not there maybe the frame can move around more.

Don

 

I have an extremely rigid frame, being fully boxed and two additional crossmembers. Bottom line, the newer version of those mounts are not nearly as beefy as the ones I bought 5 years ago. The outrigger is the same, but the mount plate and the way the outriggers are attached to them are not as strong. Wish I had taken some pics before I put the newer ones back in. Also, I was using the mount holes that were closest to the frame so my outriggers were quite long. I did that originally because I thought the frame brackets weren't strong enough to put the weight out on them that far. This time I used the holes that are closest to the engine so the outriggers are short, less leverage on them. I've already been on a much tougher trail with the new mounts with no problems now that they are re-inforced with some 1/4". Maybe I can get a pic of them, but it's awfully dark and crowded down there.

 

So the factory knew what they were doing when they put a short mount on the engine and the long part on the frame

 

You could say that. Definitely the factory mounts are superior to Novaks. I can't speak for the Advance Adapter parts.

Warloch: I hear what you are saying about looking like the bolt holes are being pulled in, but that's not the case. The block is flat where they bolt on. The plate has been stretched upward between the bolt holes.

 

Here's how I setup the original mounts that I bought in 2005. I'm fairly certain I would not have had a problem with them in normal use. However the replacement mounts I just received look similar but the outrigger is cutout at the bottom where it is attached to the mount plate. I'd guess that the lack of contact at the bottom and the thinness of the plate allowed the plate to bend between the bolts. I'll see if I can get a pic of the existing mount, but I think the re-inforcing plate I made is going to block a good shot of it.

 

OK, the mount plate is the same thickness on the older mounts and the newer ones. 3/16" nominal. They differ in two ways from each other. The outrigger is a little lower on the mount plate, thus dropping the engine in the front about 5/8" and the outrigger on the newer mount is notched at the bottom where it attaches to the plate.



I plan to call Novak on Monday and see what they think. Like I mentioned earlier, I've always been happy with their stuff and I've used quite a few of their parts.

 

Just my opinion but I think the factory Dauntless mounts are superior.
Excepting a few cases of rubber deterioration I have never seen a failure of the factory insulator pad nor the frame brackets.
With the factory system the thick insulator pads are located directly up against the engine block.
In that specific location the maximum engine movement is allowed by way of minimal flexing of the pad itself.

 

I have to agree with Oldtime. with the flex at the motor less chance of block flex and leverage on the frame causing frame twist and flex. Even if the frame is boxed with that much leverage the frame can twist. One of the reasons I use stock style rubber insulators and build my own frame mounts or use stock frame brackets. I've actually seen blocks crack around the mounting points or pull the threads out of the block with those style.
I also like Novak's stuff, but don't like the design of that style of mount or Advance Adapters mounts.

 

Have to agree, I think factory mounts are the way to go. I cut the factory mounts out of a '67 Commando frame and they worked perfectly in a CJ2A I built 20 years ago. What better way to get the engine located perfectly. If you look at a factory V6 firewall you'll also see the factory "patch" piece they used to clear the drivers side valve cover on the V6. You can cut this piece out of a scrap tub and it fit's perfectly on a flatfender tub after cutting out the corner.