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Ok I did something kinda stupid the other day. When I was taking out the two front engine/transmission crossmember bolts, they sheared right off. I drilled them out but wasn't paying attention and used a 1/2" drill bit (taking the threads with the bolt).

For now I drilled all the way through and used a long bolt with a big washer on the other side of the frame rail. But I'd like to retap the two holes.

Does anyone know what's on the other side of the bottom of the frame rail (inside the tube)? Is it a nut, or some kind of bar? If I use, say, a 9/16" tap, would there be enough metal for it to be safe?

I had basically the same problem, except i was rattling on them with an impact, and one of the bolts nut that is in the frame rail broke loose. They are just spot welded on. And now i cant take my crossmember off anymore, i can just bend it out of the way

-If you drilled it with a 1/2 drill, theres no way a 9/16' tap will work, thats way smaller. I think they are originally a 10mm metric bolt, just go up to a 12mm.

-Ryan

ryan_Fuerte wrote:I had basically the same problem, except i was rattling on them with an impact, and one of the bolts nut that is in the frame rail broke loose. They are just spot welded on. And now i cant take my crossmember off anymore, i can just bend it out of the way

-If you drilled it with a 1/2 drill, theres no way a 9/16' tap will work, thats way smaller. I think they are originally a 10mm metric bolt, just go up to a 12mm.

-Ryan

Yeah but you're saying it's a spot-welded nut on the other side... so I must have drilled out most of it with my 1/2" bit (ie. there's not much left to thread). I guess I'll just leave it as it is. There shouldn't be too much stress in the downward direction since launches should rotate the engine against the front frame rail, right?

That is the most used motor mount. You need to get it fixed properly. Call a exhaust shop or body shop and see if they can weld a new nut in for you.
I'm not 100% clear on the mount you are talking about. Is it the one under the radiator? If so then it is the most important mount. The second most is the rear one.

PATDIESEL wrote:That is the most used motor mount. You need to get it fixed properly. Call a exhaust shop or body shop and see if they can weld a new nut in for you.
I'm not 100% clear on the mount you are talking about. Is it the one under the radiator? If so then it is the most important mount. The second most is the rear one.

Damn. Yeah, the one under the radiator.

Well, I'll be doing the KLZE swap in a couple months so when I get the old engine out I'll cut open the tube and weld in some new nuts.

Thanks for the warning.