starter and tranny bolts wont stay in....help?

last year i was unfortunate enough to hydrolock my motor and snap a rod in two, sending one half through the side of the block causing me to replace the ol' 89 4.0 block with a newer nvh 4.0 block out of a 99 xj. ever since in order to remain driveable, i have to crawl underneith and re-torque my transmission and starter bolts or else they will fall out while i drive. i have tried lock-washers and loc-tite(red and blue). when i originally installed the parts i used the torque specs from alldata and mitchell on-demand, but have since just tightened the bolts until they they no longer turn. this is very annoying and would like some other ideas.

j_epcherokee said:

last year i was unfortunate enough to hydrolock my motor and snap a rod in two, sending one half through the side of the block causing me to replace the ol' 89 4.0 block with a newer nvh 4.0 block out of a 99 xj. ever since in order to remain driveable, i have to crawl underneith and re-torque my transmission and starter bolts or else they will fall out while i drive. i have tried lock-washers and loc-tite(red and blue). when i originally installed the parts i used the torque specs from alldata and mitchell on-demand, but have since just tightened the bolts until they they no longer turn. this is very annoying and would like some other ideas.

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What size length bolts did you use? Manual or Automatic?

i used the original bolts..... automatic..... not sure about the size, its been a while since i've checked. just came back to town after being away for 6 months and i dont really feel like working on it alot right now. I just want to get it fixed so i can get back on the road.

Really stupid question time - did you use the correct size of bolts?

You'd be surprised, I've seen some strange things under people's hoods. And yes, I'm dead serious about that.

If you're dead damn certain you've got the right size bolts, check some of the specialty manufacturers/suppliers (McMaster-Carr and MSC Direct come to mind) for bolts with Nylon buttons on them - the Nylon deforms and locks the bolt into the hole. Used in conjunction with LocTite, there's no reason at all for them to come loose after that.

If that doesn't work, I'd go on the assumption that the threads are thoroughly deformed, and install Heli-Coils to repair. This will give you a clean thread of the same size, and I've NEVER had a Heli-Coil repair fail me in over 20 years!

5-90

thanx for the heli-coil reminder i have used it before on another application but never thought about it for this...

The only other thing that comes to mind is that for some reason your bellhousing is not really pulled up all the way.
If thats the case then you will never keep them in.
After you tighten them try a .002 .003 feeler gauge between the block and bell.
I'm thinking one or both of the dowels has missed the whole and is mashed, as it mashes more your bolts are loose again.

I am gonna bet you have the wrong bolts in their. If memory serves me corect one is standard the other is metric and their lengths are very different too.

Pete