flywheel housing crack repair?

afuncar

Senior Member
can anyone tell me if they have a method to repair a flywheel housing or is it best to keep looking for one with no visable cracks that ring. I have one with no visable cracks(after cleaning) but, doesn't really have a clear ring.
 
I'm sure you can repair it but I would keep looking for a good one. They are dime a dozen! Why worry about one that has been repaired after you spend all the time and money putting everything together.
 
Many flywheel housings are found cracked at the two lowest mounting bolts. My theory for the cause of the cracks is people jacking the front of the motor up to remove the timing cover to change the timing gear. If the housing is bolted tight to solid rear motor mounts something has to give.

I would not worry so much about the cracks, what is important is that the housing is not twisted out of shape. When putting an engine together it is prudent to check the run out of the upper 180 degrees of the housing with a dial indicator. According to Ford it should be within .006.

When making this check I make a .015 thick paper gasket to be installed in concert with the two horse shoe shaped .010 metal shims that install behind the ears at the top of the housing where the throttle linkage installs. The paper will crush down to be somewhere close to .010. Most gaskets supplied by suppliers is not thick enough. I have a pair of shortened mounting bolts to use at the ears so that all six bolts can be torqued down evenly before the dial indication measurement is made.

I have put a number of engines together with cracks at the two lower mounting holes and they worked fine as long as I was able to dial in the top 180 degrees of the housing. The bottom 180 degrees of the housing is not a concern as it is very flexible and is pulled into alignment when the bell housing is bolted up.

If there is concern about the two cracks at the lower mounting bolts drill a small hole in each at the end of the crack to keep it from lengthening.

I have never been able to tell anything about tapping them with a hammer and listening to the sound. They all sound the same to me.

Tom Endy
 
I'm sure you can repair it but I would keep looking for a good one. They are dime a dozen! Why worry about one that has been repaired after you spend all the time and money putting everything together.

If you are serious about this, I sure would be interested in purchasing 12 'good ones' from you. My experience has been that cracked ones are the 'dime a dozen' ones.
 
When I first got my S/W sedan,it would jump out high gear going down hill.I noticed the F/W hsg had been brazed in several places & when I removed it,it was warped.I installed a good hsg & problem was fixed.
 
I suspect many of them are cracked by dragging them on the floor. Since there is very little strength in the housings I used ones with cracks at the lower bolt holes without hesitation. The strength is all in the cone shaped transmission housing and once it's attached the flywheel housing is almost just a spacer cannot flex.
 
I agree with Brent, I would like to have 10 or 20 of those "dime a dozen" good ones you have. I find 8 out of 10 are cracked. I can make even the cracked ones work correctly if, they are not too bad.
 

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D.J. Barev; I would say no because you're creating a stress riser in the cast iron.Whereas you have to heat it to the point of the silver to fuse to the iron.
Where this area is in constant twist due to the wishbone torque forces I wouldn't recommend doing so. The pinning relieves the stress due to the drilling on the crack and then strengthening that area by drilling and pinning across it.

To those who don't want to spend alot of time looking I would suggest trying to find a late 1931 as it is reinforced on the inside and these flywheel housings don't crack.

I've enclosed photos for anyone to readily identify the good ones from the 8 out of 10 pile.
 

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I'm new at this so bear with me. Fortunately, although they are cracked, nothing much falls apart. You only know it's cracked when you see the crack. It seems to be a harmless condition, but one that will bug the hell out of you as long as you know it's there. I have a FW housing with a small (Short) crack in it. Since it's junk now I can't hurt it. I drilled a small "Crackstop" hole at each of the crack end to prevent the crack from getting longer. I'm debating in my mind whether or not to to drill along the entire crack and fill it with braze or just what to do. Of course, if I braze it I'll have to, heat the entire thing up in the barbecue and apply even more heat to the area of the crack to apply the braze. I dunno! Anybody got a suggestion?
Terry
 
Here in my town I have access to a place called Automotive Block Welders. The have ovens to heat blocks and exhaust manifolds to weld them. When I have cracked flywheel housings, I take them to this outfit to weld the cracks. The key issue is to find someplace that can weld cast iron that has to be heated in an oven to weld it correctly. Some welding shops claim they can weld cast iron and only heat the area they will weld with a torch and that is it. Not the same thing as using an oven.
 
If you are serious about this, I sure would be interested in purchasing 12 'good ones' from you. My experience has been that cracked ones are the 'dime a dozen' ones.


come take a trip to Canada. All the ones that I have seen and sandblasted have been perfect. Haven't ran into one yet that has cracked. Going on 8 Model A's. Maybe just luck? who knows!
 
I also thought cast iron needed to be heated to a certain temp. so the weld would take, but where I work, they don't pre-heat. I work for a company that manufactures machines related to agriculture. A lot of the parts are welded cast-iron and receive a lot of heavy stress and they hold up fine. The one mig welder guy told me you have to use a high heat setting and use nickel wire. I'm not sure if nickel wire is readily available, but if I find some i'd like to try it.
 
OK, Maybe it's cast steel or wrought iron. Maybe they have worked a system of welding that is unique to the parts involved but can't be used elsewhere.
Generally speaking, Cast iron has to be preheated and the hotter the better. The nickle rod for stick welding is available under the name of "Ni-Rod". I have used stainless rod in a pinch. The MIG reels are probably available from a welding supply house.
Terry



I also thought cast iron needed to be heated to a certain temp. so the weld would take, but where I work, they don't pre-heat. I work for a company that manufactures machines related to agriculture. A lot of the parts are welded cast-iron and receive a lot of heavy stress and they hold up fine. The one mig welder guy told me you have to use a high heat setting and use nickel wire. I'm not sure if nickel wire is readily available, but if I find some i'd like to try it.
 
The only crack that is bad is the one around the cam shaft that is caused by the motor mounts. This one wil aloow oil from the cam shaft to leak and you will believe it is the normal leak but it is much more. As critical as the alignment is and can be way off if cracked I brought a new one that is reiforced at this point and now I don't wory about it. I tried many used ones and they were warped and cracked. Welding a large flimsy housing is ricky in it's self and the warp is much worse than the crack.
 
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