Ford 9" 3rd member case/housing cracked? Or casting mark?

tirewater · May 29, 2019

While looking over my 9" housing, I noticed a lip in the metal that *could* be a crack. There is no sign of a crack on the inside of the housing.

Is there an easy way to determine if this is a crack or simply a casting mark? I've wire wheeled the clear coat off for a better image.

Heh, I can't seem to catch a break (no pun intended) with rebuilding my Ford 9 rear 3rd. Ultimately I've bought new gears, new trac-lok (x2 as one had severe runout), good used pinion housing, and now it seems a new 9" 3rd housing as well.

Thanks,
Chris

DirtDonk · May 29, 2019

One break, comin' up!
I'd have to say it's a casting edge. Sure does look like a crack would look though!

But my vote is for casting flaw. Especially since you say it's not showing through.
The edge of it looks offset (one side higher than the other) so that's my clue.

Best of luck with it. Not sure how to truly test that theory (such as with Magna-Flux or whatever method) but there may be some way. Heating mildly with a torch to see if it opens up?
Not sure but if someone else's housing has that same one, you're good to go.

Paul

bax · May 29, 2019

best way to tell is go after it with a sanding wheel. Smooth it out and see if it is a crack. Crack is wack

Timmy390 · May 29, 2019

First pic looks like a crack but the second and third look like casting.

Agree with some sandpaper....see if it smooths out......

Tim

broncosam · May 29, 2019

Looks like a casting mark to me, but I'd still sand on it a bit to be sure.

Broncobowsher · May 29, 2019

Looks casting to me.

Justafordguy · May 29, 2019

X4, flap wheel it, then you will know for sure.

tirewater · May 29, 2019

Thanks, I'll grind it down some to see how far the imperfection goes. It's definitely a ridge/lip, but it's not obvious if it's cracked in addition to the ridge being there.

markatherton · May 29, 2019

crack

Clean the area thoroughly. Turn it upside down so you can pour oil in the area and see it it leaks through.

tirewater · May 29, 2019

markatherton said:
Clean the area thoroughly. Turn it upside down so you can pour oil in the area and see it it leaks through.

I don't think oil will make its way through the crack. The crack extends into the casting. I believe it's likely a casting imperfection rather than a crack, but crack nonetheless.

I couldn't get a flapper in there, so I used the dremel.

Fun time$. This started off as fixing a leak, and has become a piece by piece replacement of the 3rd. Would've been cheaper to just to buy a completed 3rd. Lol...

Now I have to find another 2.89" 3rd case. Or scrap the new bearings I just pressed onto the carrier and buy a set of the 3.+" ones. I don't see much in the way of 2.89" 3rd member cases laying around.

bronkenn · May 29, 2019

Paint it with POR15 and it won't leak.

bax · May 29, 2019

at this point I think thats a crack. I may have a small case laying around but like you said. It's upgrade time.

capt2130 · May 29, 2019

Try some liquid dye penetrant.

5001craig · May 29, 2019

FWIW it looks like a crack to me.

Could you weld it up with some nickel or better rod? After disassembly. I seem to remember one of the electrode manufacturers made some rod that worked well and flowed well too. May require pre/post heating. Torch for preheating and cover in ceramic blanket to cool slowly. I've done this in the past on other items but I'd talk to someone more knowledgeable than me about your 3rd.

After confirming it's a crack.

Rustytruck · May 29, 2019

Heliarc with everdur rod. If its been there for 40 years why worry about it now. Now if your building a hard core offroader that may be another issue.

There is also a special silver solder out there.

https://www.muggyweld.com/product/ssf-6-silver-solder/

sykanr0ng · May 29, 2019

capt2130 said:
Try some liquid dye penetrant.

/\/\ Take it to an automotive machine shop and have them Magnaflux it.
Either way you will know.

WILDHORSES · May 31, 2019

DirtDonk said:
One break, comin' up!

Crack or not I've noticed an uptick in housings breaking apart out on the trail. This stuff is 50 years old and if it's been abused or if you plan some abuse a good nodular housing will only set you back a few hundo.

Jim

tirewater · May 31, 2019

WILDHORSES said:
Crack or not I've noticed an uptick in housings breaking apart out on the trail. This stuff is 50 years old and if it's been abused or if you plan some abuse a good nodular housing will only set you back a few hundo.

Jim

Thanks Jim. I have a Currie Nodular case coming to the house today or tomorrow. Ultimately my 3rd did have problems that may or may not be related to the case imperfections. In addition time spent finding a 'good' used case is considerable as this area is the land of no convenience.

The main annoyance is time wasted and spent on the existing setup. Cleaning and a ridiculous amount of assembling and disassembling. I'll be throwing away a second set of brand new carrier bearings when the case comes in (no aftermarket cases use the 2.983 bearings.)

suckerpunched · May 31, 2019

I might have one, I am a few hrs south of you. Is there an easy way to identify the 2.89 case vs the 3.0?

DirtDonk · May 31, 2019

And don't throw away the brand new bearings just yet. Most members have the same size and someone might need them.
If you have the time to do it, they might go quickly.

Paul

Ford 9" 3rd member case/housing cracked? Or casting mark?

Sr. Member

Attachments

Bronco Guru

Old Member

Bronco Guru

Bronco Guru

Total hack

Bronco Guru

Sr. Member

Bronco Guru

Sr. Member

Attachments

Bronco Guy

Old Member

Jr. Member

Bronco Guru

Bronco Guru

Bronco Guru

Bronco Guru

Sr. Member

Sr. Member

Bronco Guru

Similar threads