Aluminum engine mount failure! Pics inside.

[IsaacHayes]

Yeah, the big 3/4" thick or so aluminum main engine mount broke... W....T...F...

I have a polyurethane insert in there along with the rubber, but would that be enough to cause THIS:

[kflo 93 gt]

Over torquing would cause that, all day.

[Tofuball]

Fatigue over a long time? Thanks for sharing those pictures :O

[IsaacHayes]

KFLO: overtorqing? Are you saying my engine has too much torq? How can you over-tighten those bolts and cause that though? I don't get it.

Tofuball: I'm thinking (hoping) the same. Perhaps before the poly mount it developed a stress crack from bottoming out the mount slamming in the back side. And now that it's solid it just sheared away??

[mcgavinz26]

Ouch, sorry about your luck. At least it wasn't a clean break and your engine dropped down on that side while you were driving or something.

I had poly inserts in mine, the mount itself was fairly new (the mount, not the bracket), I had wheel hop pretty bad, and I didn't manage to break mine. Maybe yours was a bad casting?

[PCGUY112887]

How did you notice it cracked? Just see it or could you feel it?

[IsaacHayes]

Scott: Yeah I'm glad it didn't fail while driving. That could of broke the oil pan or worse. Thanks for the re-assurance. I haven't had the poly in for long that's why I suspected that caused the crack. I'm guessing it just brought out the crack... I'm hoping it's a weak cast or just fatigued from over the years. I left it at the junkyard so I didn't break it in half to see. The underside was cracked all the way across though it was about to drop any sec.

PCGUY: I noticed it when I was converting to the 3 wire CTS, just happened to see it and freaked out! I didn't feel it because there isn't much space between the crack. If I felt it, it would of been too late. I converted to the 3 wire CTS because I didn't feel like replacing the bad sender in the rear head LOL.

[ForcedFirebird]

Good thing it didn't break through! One more burnout, though...

HMMM, wonder if this is a common thing? Maybe a new billet piece needs to me made?

[IsaacHayes]

Hahah Funny you say that, I did do a few burn outs recently. 185 width cheapy winter tires, parking lot, and a few jabs of the throttle = nice marks.

A few guys on bstuff are thinking of billet now too I think after seeing my pics. lol. Looking in the crack of the old one it shows how crappy cast metal breaks apart.

[ForcedFirebird]

Hahah Funny you say that, I did do a few burn outs recently. 185 width cheapy winter tires, parking lot, and a few jabs of the throttle = nice marks.

A few guys on bstuff are thinking of billet now too I think after seeing my pics. lol. Looking in the crack of the old one it shows how crappy cast metal breaks apart.

Guess you'll have to send the broken one to be copied

[mcgavinz26]

Is the torsion mount at the bottom of the engine right above the subframe? So it the engine would fall and rest on the subframe.... maybe? Hah, I can't imagine how that would feel, or sound for that matter, and the car would probably still be able to move.

[IsaacHayes]

FF: I left the broken one at the junk yard. It's on 95+ beretta's, coriscas, grand ams, and skylarks. Not sure what was the last year for that mount. 97 or 98. Maybe even malibus had it. I got another spare though and if this new one rips I'll send it to you and throw the spare on. But if you want to copy and make them I could send the spare one I have now. But with a billet one, I have to wonder if it would then crack the timing cover?? lol I guess the bolts go through it to the block and should be ok. Having billet though would defiantly hold up!

Scott: yeah there is the torq strut down there. The subframe might stop the motor but no doubt that pulleys, wires, and other shit would be busted up. I'll upload pics in a minute of the back side of the mount and what I did when I got the new one.

Drove for a bit tonight road testing it. Man it's a big difference being in a car that pulls your head back!!! I was driving a Ford Taurus to the junkyard today in the meanwhile and floored that car will barely get up to speed soon enough getting on the highway.

I feel nervous though, from driving it around the block flooring it. I feel I should pop the hood now and expect to see I broke it again!!! LOL God I hope it lasts.

[IsaacHayes]

A view from the bottom: (almost through!!)


Side:


I got a new rubber top piece too. This was worn before the polyurethane insert:


New mount has less rough casting seems (or at least ground more by the factory) than old. But I will still get rid of them.


Like so:


A little turtle wax to remove dirt and oxidation:


BLING BLING Yo

[mcgavinz26]

Wow, you really must have been a burnout or two from a serious problem.

[bszopi]

If you have a big enough scanner, take your spare one and scan it in and save it as a PDF. Then email it to me. I can then recreate it as a CAD drawing and send it on to FF. I can also verify I have the right dimensions by going out and measuring the one in my car.