theiceman

need some worldly experience..
I was taking off the transmission mount crossmember and ran into a little trouble. the mount is held on to the transmission by 4 nuts on studs, 3 of the studs came out with the nuts on , no big deal really, but of course the 4th just rounded off , just rusted right in I guess. So then I figure , okay just leave it , put it back and change the mounts right under the car, one went fine but on the second, the nut just spins on the rusted bolt so I can't remove it . So now I can't remove the cross member to work on the bench, so I can get the rusted mount bolt out, and I can't remove the mount either .

any one have any suggestions ?

I am considering grinding off the stud and rusted nut to release the cross member and then working on the bench, putting it back with only 3. I don't think I will ever get that stud out without removing the transmission. I could maybe get some heat on the stud , but there will be very little left after grinding.

My second option is to leave the cross member in tact with the one rounded stud/ nut and grind off the nut /bolt on the mount, this will be WAY harder given the location but at least everything will be secured properly in the end, even with a rounded bolt. I may do a little superficial damage to the cross member too as it looks tight in their.

Just thought I should ask before i take it to the shop and get charged extra for "working on it first "

TonyG

Cut the nut off with a Dremel.

Then once you get the cross brace off, use vice grips to remove the stud.

(verify, since without having one in front of me right now to see it, I could be wrong.... but I think you should be able to do it)

TonyG

mwildt

Hi,

I can't remember how that exactly looks, but I'd try to heat it first several time and then use a plier to try to turn it out/off. PB blaster, rust desolver, then heat it after it's been soaking for a while. Grinding would be absolutely last resort since you need the stud as long as possible to get it out proper.

Others may have better ideas, but heat I'd try first.

Michael

theiceman

Thanks Guys . I have nothing left to grab a hold of so grinding ay be my only option.

mwildt

One sec. Can you post a picture ? others might come with better solutions.

Michael

theiceman

sure , hang on a couple of minutes....

I am on a conference call for work and will snap a pic as soon as I can .

theiceman

okay here is the pic .. caution some pictures are graphic in nature... image of totally butchered hadware....

TonyG

Where is all the penetrating oil?

You shoud spray the hell out of it , over and over. Let it sit unti tomorrow. Then try one last time with vice grips.

Also... that cross member looks pretty rusty. You might want to consider finding a good used one.

mwildt

I agree with TonyG, only cut off the nut. Leave the stud as is so you can heat it and get it out so a replacement can be inserted. You could still try heat (make it really hot) and potentially use a chissel to tap the nut off.

Michael

r911

yes do TonyG's procedure first - but for 3-4 days w/ oil & tapping the nuts over & over

then do Michael's nut slicing - use a Dremel w/ cutoff wheel AND GLASSES - you make a vertical slice thru the nut so you don't hit the stud

must a been an exciting conf. call since you were cruising the net...

911 Rod

I think Ice is saying the nut is turning on the stud.
Can you get in there with the dremel and cut the nut leaving the stud behind?
Looks pretty easy from where I'm sitting.
Hey Ice. I thought you were done. Does it ever stop?

theiceman

Thanks guys she is soaking as we speak. I bought some MPS gas as it is hotter than propane. Actually all 3 of the other studs came out with the nut so I need 4 new studs - dealer only ? If I manage to cut the nut off at least I will be able to drop the cross member and check it out.

I will update later this weekend as I iwll let it soak overnight at least .

theiceman

Well to answer a few questions .... 911 ... it NEVER STOPS .. just as I think I am done I get the bug again and look for something else to do , usually I just end up reading one of Petes posts to some one and end up thinking .. hmm I could do that ! My motor and transmision mounts are actually in perfect shape and it looked doable so I though why not !!
The actual stud in the picture was rusted solid , the nut that turned on the bolt was one of the ones holding the mount to the cross brace. So I was screwed either way ..
Tony , your advice and Randys was the trick that turned it for me in the end. But the answer was staring m right in the face the whole time and I didn't see it until half way through my spaghetti dinner... I had an epifa... epife....apifin.... a great idea ... I jumped up and darted outside while I had some light . I crawled under and I new I had the answer , the thing I was missing was leverage on that nut and stud and I was starring at it the whole time. I took eveything else off the brace and tried to twist it , it moved..... about a 1/16th at each end of the brace, so I twisted it back and forth for about 5 minutes and it was moving completely freely by then, the stud and nut was not moving on the brace ( actually a good thing ) but the brace nut and stud were all turning about 10 degrees ,, this meant the stud was now loose in the transmission , the best possible scenario, worse case is I neeed a new stud. So then I used Tonys and Randys advice and cut down each side of the nut vertically. I didn't care if i damaged the threads . I was then able to use a chisel to nock the bits off and then the vice grips to turn the nut off .. still very difficult. I got the nut off and the brace fell. then I put the vice grips back on the stud and it came right out as I had already worked it loose .. although I think heat is a great idea i do not like using torches unless I have to. especially since I am an my back under the car .... hell I can't be trusted with a hand brake .. are you gonna give me a torch too ?

PS tony if I replaced everything rusted on my car I would have a kit car and none of the original left. I will pound down where somebody put a jack on it and take the surface rust off , repaint .. as they say that will buff right out ...

I guess I will have to get the studs from Porsche unless someone knows of another source as they will be metric thread, and the nuts are exhaust nuts , not the regulars, no wonder they were completely rusted on there.

Thanks for all your help guys, so glad I didn't rush in and grind it off without asking first.

TonyG

theiceman

The reason I commented about the transmission mount is that while the transmission serves as the torque arm, the mount transmits the entire load to the body.

All the torque of the engine is transmitted to the body through this piece of metal, thus is a fairly important piece.

Considering that the specific location of the corrosion on the mount is exactly where the transmission transmits its load, it's a problem.
The good news is that the brace is very inexpensive used and easy to swap out.

Something to think about...

TonyG

r911

having read posts exactly like this for several years, I can't believe how lucky I've been with the fasteners on both 911s I've owned...

anyway, know that you aren't alone...