Stripped bellhousing to transmission threads

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Coal creek Chris

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Ok, had another idea. Let's have some fun with this for the sake of discussion and creativity. What might work that would hold tight but I wouldn't have to take out the transmission and bell? Knowing that these ideas would wreck the bellhousing holes.

1. Use one of those expanding anchor bolts, like for concrete, where I use a nut on the transmission side rather than it being a bolt head on that side?
2. Use some sort of self cutting/tapping bolt that basically cuts its way in and holds snug?
3. High heat epoxy to anchor in a stud in the bell holes and then use a nut on the transmission side?

I know these are all bozo/hack fix ideas but sometimes the best fixes are the temporary ones that work.
 

AuroraGirl

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Ok, had another idea. Let's have some fun with this for the sake of discussion and creativity. What might work that would hold tight but I wouldn't have to take out the transmission and bell? Knowing that these ideas would wreck the bellhousing holes.

1. Use one of those expanding anchor bolts, like for concrete, where I use a nut on the transmission side rather than it being a bolt head on that side?
2. Use some sort of self cutting/tapping bolt that basically cuts its way in and holds snug?
3. High heat epoxy to anchor in a stud in the bell holes and then use a nut on the transmission side?

I know these are all bozo/hack fix ideas but sometimes the best fixes are the temporary ones that work.
your dancing around the thing you should be doing. its your truck, you dont have to do anything
But if you have an aluminum bellhousing especially, realize that those few bolts are doing a LOT of work for your heavy looking truck which takes heavy loads/trailers Think about the torque you put down and think about the weight you want to move from here to there

If its steel, id think you are still just opening yourself up for it to crack rather than break which could eventually be disaster but stresses can pile up over time.
If you want us to tell you a lie and say those are good ideas we can. Not saying epoxy, puddy cant be good. But they almost certainly dictate a "surface prep" in their instructions.

You arent gonna be doing that on the truck
 

Coal creek Chris

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your dancing around the thing you should be doing. its your truck, you dont have to do anything
But if you have an aluminum bellhousing especially, realize that those few bolts are doing a LOT of work for your heavy looking truck which takes heavy loads/trailers Think about the torque you put down and think about the weight you want to move from here to there

If its steel, id think you are still just opening yourself up for it to crack rather than break which could eventually be disaster but stresses can pile up over time.
If you want us to tell you a lie and say those are good ideas we can. Not saying epoxy, puddy cant be good. But they almost certainly dictate a "surface prep" in their instructions.

You arent gonna be doing that on the truck
True, it is taking heavy loads and is a dump bed. The bellhousing is aluminum. It wouldn't be possible to do any decent surface prep in there for an adhesive approach because its a greasy mess.
 

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True, it is taking heavy loads and is a dump bed. The bellhousing is aluminum. It wouldn't be possible to do any decent surface prep in there for an adhesive approach because its a greasy mess.
yes, you are making part of my point. Cough cough. What does the little guy on the other shoulder tell you to do?
 

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You can also thread the holes and drill the ears on the tranny to accept 11/16" bolts if the existing one are 5/8". Keenserts are the way to go if you keep the original size.
 

Coal creek Chris

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yes, you are making part of my point. Cough cough. What does the little guy on the other shoulder tell you to do?
The other guy in white says I should fix it like a pro and upgrade to a bellhousing that can take a lot of abuse, if such a thing exists. He also says, maybe its time for a more modern truck.
 

whiskeydents

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Not sure if you were still dealing with this problem, but during my 465 swap, I noticed that the donor bell housing threads were mostly stripped. I just ordered 4 FULL THREAD bolts (3 inches long if I remember) online through fastenal. I ran a tap through the bell housing to clean the threads up and then flattened out the casting flash on the inside on the housing where the bolt heads would sit. I then just ran the bolts from the inside of the bell housing turning them essentially into studs for the transmission to slide onto. I had to use a die grinder to clearance the transmission “ears” to make room for lock washers and the nuts so that they would sit flat. Worked pretty slick for me as it allowed the transmission to be aligned on the studs before trying to align the input and all that.

-Morgan.
 

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You might try a little longer bolt first, if you could grab more than a couple threads you might be okay? Just a thought
 

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You might try a little longer bolt first, if you could grab more than a couple threads you might be okay? Just a thought
Thank you!
2 pages later…
@Coal creek Chris, slow down for a sec. And don’t get too wound up about the comments about how you fix it.
But the top things I’d try first is what @Loren said. 1/4” or 1/2” longer bolts may work.
If not and they are almost grabbing and not just completely void of threads is stuff a piece or 2 of stranded automotive electrical wire in each hole. Insulation and all. Trial and error to find the right gauge but we all have wire laying around.
Very Good chance they will grab and tighten up sufficiently.
Free and easy.
Been using red neck Helicoils like this for a long time.
If neither method works then move on to more complicated solutions, that don’t involve epoxy or concrete wedge anchors. Although I kinda like the wedge anchor idea.
Have used 1000s of them in concrete. Never thought about them as a repair for stripped threads though. That actually may also work as well as it seems it may.
Just know they’re not coming out unless you can punch them through should you ever need to remove them.
 

Grit dog

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Damn, there’s a YouTube for everything!
Well, never claimed the redneck heli coils were the best, and would expect tapped inserts to be far superior , but I’m pretty sure I’ve put more than 130 in lbs on some.
 

89Suburban

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Thank you!
2 pages later…
@Coal creek Chris, slow down for a sec. And don’t get too wound up about the comments about how you fix it.
But the top things I’d try first is what @Loren said. 1/4” or 1/2” longer bolts may work.
If not and they are almost grabbing and not just completely void of threads is stuff a piece or 2 of stranded automotive electrical wire in each hole. Insulation and all. Trial and error to find the right gauge but we all have wire laying around.
Very Good chance they will grab and tighten up sufficiently.
Free and easy.
Been using red neck Helicoils like this for a long time.
If neither method works then move on to more complicated solutions, that don’t involve epoxy or concrete wedge anchors. Although I kinda like the wedge anchor idea.
Have used 1000s of them in concrete. Never thought about them as a repair for stripped threads though. That actually may also work as well as it seems it may.
Just know they’re not coming out unless you can punch them through should you ever need to remove them.


Or a piece of threaded rod bottomed out in the good threads then a nut and washer on top?
 

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I used a product, many years ago, that I had great success with called Locktite Form-a-thread. I used it on a transfer case to transmission bolt that was stripped out. Key is to get the hole and bolt VERY clean. Ran it that way for many years. Only problem I had was when I went to rebuild the case a few years ago, I twisted the bolt off when I tried to get it out. Not sure how it would work on an engine to bell housing, but if done right it is VERY strong
 

Ricko1966

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I'm sure this is fixed but it seemed like a good place to throw this in so you all can put in your memory in case you ever need it.
@Grit dog was talking about redneck helicopter coils,I'm going to tell you how I make redneck helicoils. I prefer to just buy and use heli coils but being an hour an hour away from everything it's not always possible,and sometimes you have to order the kit you need. Here's how I do it find a bigger bolt that I have a tap for clamp a chunk of 2x4 in the drill vice bore a hole your new bolt will fit snug in.Don"t move your wood or the drill vice,put your bolt in the hole,put a combination wrench on it, use the drill size for what ever bolt you stripped outs tap size to drill a pilot he in the bolt. Now you have a bigger bolt with a hole centered.Use the hollow bolts hex head and screw it into your retapped bolt hole. Keep your wrench on it and tap the I.D. to the size you need then drill or grind the head off. I know Pita but if you have to wait a day for a heli coil you do what you have to.
 

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