Cracked 4R100 case at banjo bolt/return

[TurboM700]

You could try a good epoxy like a Lord Adhesive. Its a used alot in Aviation and Off road industry to bond anything to anything. Like Alum to steel. Plastic to alum etc.

Do not mig it. You will just burn it right off there.

Todo it right you will need to pull the tranny and get it on its side and find someone with a TIG welder that is really could with Alum.

If it was me it would get taken down everything pulled out. Hot tanked then grind the affected area back up with a TIG welder machine it down and rethread it.

After all that you might be money ahead to just replace the case.

 

[rammertide07]

opcorn:

 

[tensixniner]

Damn, this thread turned hilarious fast.

I see your point but welding with a tig torch and having you a/c balance set for higher cleaning action, cleaning with chemicals will not remove enuff of the oxides and will require higher cleaning action dialed into the machine because of the condition of the metal means you will put a conciderable amount of heat in the base metal and it will heat soak just like brazing if there is rubber seals that close that you are worried about the heat then disassemble the trans and do either process.

please explain why you would not use brass or aluminum?


edit: you will have to pre-heat the base metal (cast metals expand and contract differently than the filler metals used) so ether method you will have to use a torch to heat the base metal to about 300-350*F. if it were my truck needing the repair i would braze it just because of the characteristics of welding cast aluminum.

I'll do my best to answer the post made in response to my previous one.

I'd use chemicals to degrease as much as possible.
You can play with the AC balance however you like, it's only going to help remove the aluminum oxide on the surface and won't do anything beneficial in removing the greasy dirt.
A file, sandpaper, burr ... etc can also be used to help remove the oxide layer minimizing the use of AC balance.

Brass isn't used to braze aluminum, it just doesn't stick very well. There are other filler metals that can be used which are more appropriate. For example, 4047 can be used as a brazing filler.

As far as a filler metal for welding it, there are also many choices. I'm sure one could be found which is suitable for this application.
With a suitable filler and welding procedure the weld and the untouched casting would have similar strength charactericts, assuming the part wasn't originaly heat treated.

A big part of doing this repair with welding or brazing is the skill/experience of the weldor performing the work. Also, the equipment and supplies they have available.

In summary ...
The method of repair is the customers discretion.
My personal preference would be TIG over MIG but I am also not against trying a quality epoxy first. JB Weld probably wouldn't be my first choice.

 

[rammertide07]

Thanks for all the replies guys. I'm trying to sort this out and try to find other opinions because everyone that "knows" more about this stuff than I do. Not trying to be sarcastic, I don't know enough to tell someone they are wrong...and there's a lot of disagreement. Didn't mean for there to be a argument over this.

I've researched MIG vs TIG and TIG does seem to be the better option...depending on how much it costs. I have 3 leads on guys that might can MIG weld, I'll look into seeing if they can do TIG.

I like the sound of the epoxy that TurboM700 suggested, I'm going to check that out.

I have another banjo bolt and washer in route. I know the thread count is 18, does anyone know the width of the tap I need? I believe its 7/8".

 

[Denver]

If you do tig weld it, drill, then tap how are you going to prevent all of the shavings from going into the trans fluid and flowing through the transmission? If you do go the welding route make sure you have a fire extinguisher handy. The bypass can be removed.

 

[rammertide07]

If you do tig weld it, drill, then tap how are you going to prevent all of the shavings from going into the trans fluid and flowing through the transmission? If you do go the welding route make sure you have a fire extinguisher handy. The bypass can be removed.

My wife just got a Rainbow vac, and does that thing have some suction. I have a good 45min before she gets home.

I don't think I will have to drill since I'm not going to a bigger size. I'm just re-threading the threads straight. I've considered just to use the banjo bolt as the tap. But i'll probably just use a tap and put some grease on it to cathch most of the shavings. The bypass line can already be pulled away as it is.

 

[Tom S]

:clapping:


Charles you need to take a big step back and f*** your own face you f***tard

THIS IS NOT AWOL SO BOTH OF YOU TAKE A STEP BACK.

 

[DocBar]

:clapping:

he may have engineered it to be functional but he does not know how to repair cast aluminum! you all keep doin what you are doin and i will do the same.

Charles you need to take a big step back and f*** your own face you f***tard

Wow.:lame2:

 

[dzljon]

Damn, this thread turned hilarious fast.



I'll do my best to answer the post made in response to my previous one.

I'd use chemicals to degrease as much as possible.
You can play with the AC balance however you like, it's only going to help remove the aluminum oxide on the surface and won't do anything beneficial in removing the greasy dirt.
A file, sandpaper, burr ... etc can also be used to help remove the oxide layer minimizing the use of AC balance.

Brass isn't used to braze aluminum, it just doesn't stick very well. There are other filler metals that can be used which are more appropriate. For example, 4047 can be used as a brazing filler.

As far as a filler metal for welding it, there are also many choices. I'm sure one could be found which is suitable for this application.
With a suitable filler and welding procedure the weld and the untouched casting would have similar strength charactericts, assuming the part wasn't originaly heat treated.

A big part of doing this repair with welding or brazing is the skill/experience of the weldor performing the work. Also, the equipment and supplies they have available.

In summary ...
The method of repair is the customers discretion.
My personal preference would be TIG over MIG but I am also not against trying a quality epoxy first. JB Weld probably wouldn't be my first choice.

:redspotdance: some one that knows you cant use brass to braze aluminum! this is good. thanks

 

[rammertide07]

:redspotdance: some one that knows you cant use brass to braze aluminum! this is good. thanks

I did find a good video on alumminum soldering

http://www.youtube.com/watch?v=OLvDHwQFvAM

I'm checking on some leads today I got for guys that do welding.

 

[Charles]

***tard....

Someone who would disassemble a trans, make a repair to a dime-a-dozen case and then spend all the labor to reassemble the trans back into that same case with a much higher chance of an issue compared to a perfectly good OEM case without any cross-threaded and cracked bosses repaired.

 

[rammertide07]

***tard....

Someone who would disassemble a trans, make a repair to a dime-a-dozen case and then spend all the labor to reassemble the trans back into that same case with a much higher chance of an issue compared to a perfectly good OEM case without any cross-threaded and cracked bosses repaired.

I agree, I'm not equipped to do that. So I would pretty much be paying for a rebuild + cost of the case. I would be better off buying a new/rebuilt transmission.

I'm going to try to make the repair as it is first. This piece is very exsposed away from the case..more that a crack on a flat surface of the case.

 

[rammertide07]

Well I was wrong. Called the shop just to see how much a case and swapping everything it would cost. $400 for case and $300 for labor + new seals and gaskets.

 

[rammertide07]

Does anyone know the thread system used for the bajo bolt. I think its somethink like what is used for JIC or AN fitting...if they are different.

 

[Charles]

Does anyone know the thread system used for the bajo bolt. I think its somethink like what is used for JIC or AN fitting...if they are different.

JIC and AN seal on a flare. Your threads are straight cut, but there's no flare to seal. And since they are not tapered threads the threads themselves will not seal like a pipe thread.

If you wanted to do away with the banjo bolt and go to a JIC or AN, then you would maybe go to an ORB fitting and use one of the washers with an enclosed o-ring to seal the face as opposed to machining the o-ring receiver into the boss on the trans.

Either way, unless you re-tap that hole for pipe, you'll be sealing up on that face just like the banjo bolt does.