Ford 9" question

[hossdoc]

I have never taken the center section from a Ford 9" before. Once removed, the internal lip of the axle mounting face has two big triangular gouges; one at the 9:00 and the other at the 3:00 position. Normal?? Or is this a sign of previous carnage? Anyone have any ideas as to the cause and solution? Should I be worried?

[silver69camaro]

Off hand I don't remember. But if it doesn't leak oil, what's the problem?

[parsonsj]

Once removed, the internal lip of the axle mounting face has two big triangular gouges; one at the 9:00 and the other at the 3:00 position. Normal??Yes. It seems to be an artifact of the manufacturing method. No big deal. One thing to watch for is that the bolt-pattern is asymmetrical; the gasket will almost go on backwards.

jp

[hossdoc]

I'm gonna try to post a photo for clarification; sorry if this doen't work. Weld this shut or leave it alone? It didn't leak when I disassembled it, but somene else had replaced the gasket and used some of the red sealer as well: I thought that was a bad idea. How do you recommend preping the mounting surface befor replacing the gasket? Sorry for what may be a stupid question but I've never done this repair before

[Apogee]

That's normal...it's just part of the manufacturing process. You can look inside and see the weld seem where they closed the mounting flange from multiple pieces of material.

As for reinstalling the 3rd member, I never use a paper gasket...they just get in the way. I've had the best luck with the Grey RTV once both surfaces have been thoroughly cleaned and degreased with MEK, Acetone, Laquer Thinner, brake cleaner, etc. Do you have the copper crush washers to go under the nuts against the 3rd? Some choose not to run them, but they can keep a stud from leaking if that's the case.

[hossdoc]

Sorry, the third member was out of the car for the previous owner, no washers present. Great tip though. Not to doubt your word on the RTV issue, but I thought I read in some article way back when that some rear end builder would void warrenty if RTV type sealer was used. As I recall it had something to do with small pieces coming loose and clogging some oiling port. I think the article went on to say that string or dental floss was wrapped from one stud to the next two complete rounds to provide adequate seal. However, I may be mistaken.

[justanova]

Sorry, the third member was out of the car for the previous owner, no washers present. Great tip though. Not to doubt your word on the RTV issue, but I thought I read in some article way back when that some rear end builder would void warrenty if RTV type sealer was used. As I recall it had something to do with small pieces coming loose and clogging some oiling port. I think the article went on to say that string or dental floss was wrapped from one stud to the next two complete rounds to provide adequate seal. However, I may be mistaken.

i believe that was an article in circle track mag. rtv can clog the oiling hole for the pinion bearings and cause failure, so some dirt track racers use cotton kite string instead of a gasket, but i have always used the paper gasket with no problems, i've even reused the gaskets several times.

[Apogee]

...Not to doubt your word on the RTV issue, but I thought I read in some article way back when that some rear end builder would void warrenty if RTV type sealer was used. As I recall it had something to do with small pieces coming loose and clogging some oiling port...

I've read the same thing but never experienced it myself...knock on wood. Some of the older housings are more difficult to seal, if not impossible with just a paper gasket. I don't go overboard on the RTV and have yet to see RTV anywhere other than where I put it after removing the 3rd. Sometimes it's a fight to get the 3rd in without messing up the beads of RTV...but I hold my own :box2:

[pav8427]

Notches are there to fit the 9 3/8" ring gear center section used in the full size Mercs and Fords. Probably Lincolns too.

Doug

[hossdoc]

Thanks to everyone for the help. One final post on the issue. Should I replace the studs during this rebuild; in for a penny.... What are the torque specs on the housing bolts?

[parsonsj]

The only reason to replace the studs is if you remove them to help get the housing gasket surface clean.

I've used RTV and gaskets, and I've had better luck with gaskets.

Torque specs: 38 ft-lb dry. 32 with thread lube. You won't be able to get a torque wrench on all the nuts, so you'll need to use your "elbow wrench" for a few nuts.

jp

[hossdoc]

The gasket that come off this 9" was a paper one, several of you have mentioned paper as well. Was at that dealer today to pick up some other parts. The gaskets they have for the 9" are a rubber gasket. Yea or Ney?