Banjo ratios - what are my options?

Here's one online take. There are several manuals around in repro, and it is covered in service bulletins...http://www.btc-bci.com/~billben/rearend.htm
Basically...set up carrier preload. With OEM gears, probably olde Getz as well, the normal gaskets will get you there on first try. You now have total span between bearings right, but it still may need moving sideways.
Then, assemble and tighten pinion til you have prper rotational torque. OEM is a drop in, aftermarket will require creative use of shims.
Test R to P backlash against spec...tighter or looser is accomplished by gasket change, keeping same total gasket stack thickness but adding on one side, subtracting same from other. Again, OEM is often right on at first assembly. Henry had no time for multiple tests and assemblies so tolerances were extremely tight.
For a super-low gear like this, pinion is small and fragile, so get that checking compound and throughly check out gear contact pattern.

 

HAMB tech includes a good article on 1940 install which I have never been able to find again and some discussion of setting up the new Speedway gears, which I think required pinion depth work.

 

Wow.....(huh?). I really have no idea what I am getting into. Do you know of a place that sells rear-end rebuild kits? (with bearings, races, shims, gaskets, etc...) I'm sure I'll need all that, or will the old bearings work if they are in good shape. They don't have that many miles on them. They were replaced a few years ago and treated well. Ideas?

 

Joblot has all, but if bearings are not worn and don't say "China" I would be disposed towards keeping them. Just redo gaskets and seals...I think you are putting a new R&P in, so not applicable, but I recommend measuring side gaskets on disassembly to give starting point for reassembly if keeping parts.

 

Bruce,

You think I will be fine with the bearings and races that I have? How do I get the bearings off of the pinion? How do I reinstall them onto the new pinion? These are all details that I am missing. I read the tech article that Kevin Lee was so nice to post (THANK YOU!!!). I also PM'ed "the-rodster" to see if he would repost the pictures. I think I have a grasp at how to check/set carier preload with the gaskets. (i'm assuming that Joblots has the gasket sets) Will I have to take the bearings off of the axles in order to replace the ring gear? ( I haven't had it appart yet. Trying to get all my ducks in a row before I start) Also, my grandpa told me he welded the spider gears together to make it posi. That should make checking the carier preload a little easier.

Any further tips would sure be appreciated! Thanks guys!

 

BTW...How can I tell in what year my banjo rear-end was made? I checked with Hotrodworks on kits, and they need a specific year range...

 

Bearings don't live on the axles...this is a floater rear. Bearings can be done on press at machine shop or splitter type puller...I've got all the KRW tools to pop these apart, but you're in the wrong place.
Carrier bearings if good do not need to be disturbed.

 

You'll need (assuming good bearings) new bearing nut retainer thing, pin for coupler, inner seals, gaskets.

 

Luckily, I have both!

Huh? What are these? Are you talking about the two nuts that go on the pinion?

And the pin for the coupler?

Again, please forgive my youthful ignorance. This is my first rear-end job!

 

http://www.vanpeltsales.com/FH_web/FH_images/FH_rearend-pics/Flathead_Rear_Axle_Assy_1938to48.jpg

4636 and 4607

 

Ohhhhh ok. The 4636 is a lock washer that keeps the nuts from coming undone. 4607 is a pin that connects the pinion to the driveshaft? Again, I haven't taken mine apart yet, so I don't know. what about 4637? Is that a shim/spacer? Will I need these to set pinion depth? And how about 4625...what is that? Another bearing?

 

Really just a washer...there is no formal pinion depth adjustment; at Ford, any need for that meant that someone had screwed up. With aftermarket parts, your mileage may vary.

 

As stated earlier, Joblot has install kits and gears.
http://www.joblotauto.com/specials.asp?cat_id=1&currRecord=37#

 

and part 4625? What's that?

I will have to call joblot and ask them about their install kits. I have ordered lots of brake parts from them over the past few weeks. I'm sure they wouldn't mind making another sale!

 

4625 is bearing that supports back end of pinion.
Assuming you have a '35--48 rear, only parts differences really are number of splines on pinion and differing tooth count on axles/spiders before about '38.

 

Pinion...assuming all is in spec: Once bearings and race are on, tighten nut, heat housing (spec calls for 200 degrees, boiling water sufficient...most use a torch and more heat...) drop in the assembly, mking sure it goes all the way to shoulder. Discover rear pinion bearing still on workbench, start over...
Pull down on nut to seat everything, loosen and retighten to get rotational torque to spec. (will lookup spex, but you need like a BOOK), something like 15-20 inch pounds. Tighten second nut hard against adjuster nut, holding adjuster with a wrench. Spec is to tighten til eyes protrude from head. Engage locking thing. There is a KRW tool, natch, but just find a big socket that will engage or can be ducttaped to pinion shaft, use stack of adapters to 1/4" inch pound torque wrench.
Sideways stuff...I think basic gasket is like 009...gottalookitup. Put together rear with these (turning everything backwards, I think the guy suggesting doing this BEFORE putting in pinion has a good idea), test with two people rotating for that substantial drag. Once you get there (as I said, It will oft be right on first try with original gears) distance between carrier bearings is right.
Put wholedamnthing assembly together, check pinion back lash to spec. If tight or loose, gasket thickness is removed from one side and added to other.
An alternate take used by some...set pinion side gasket thickness properly first, get back lash right, then adjust total carrier load working only with the other gasket.
Inner seals...they push in from inside. AC&R has a cheapo version of original tool (and pinion pusherouter tool) available, but basically you need a piece of pipe long enough to reach and a flat piece to support seal as you punch it in. You can feel when it is in its ring ready to smack with a hammer.

 

Ford made all this stuff the closest tolerance parts on car, especially the pinion stuff, I think...reason was all the fiddling would have been impossible when cranking out a million units per year. Pinion depth was set to rigid specs, gearsets matched and kept together, bearing depths and housing dimensions kept to tolerance for the basic gaskets. It was all made to screw together, not to be taken apart and fiddled with 87 times. I think your early RealGetzes are likely OEM quality...
Due to extreme ration, I would do checking of contact pattern. You have a tiny little pinion, and it needs to be happy.

 

Coupler pin...all hammering must be done with coupling and pinion shaft well supported with some sort of anvil. Drill old pin from one side, drive it out. New pin has one formed head, you get to form the second. With it solidly backed, poundonit. I usually heavily center punch it and surround that punching with a ring of challower punches...seems to help it get started spreading. The trick is a lot of medium blows. Betcha the new ones are Chinese replicas of pins and spread like cheddar cheese...

 

Here is my out of the box Speedway, 3:54 set up. Pilot bearing slipped right on and it appears there is a groove under the pinion bearings.

 

Ooooh...nice clean gears!!! Keep posting as it goes in. I think everyone is interested in the new 3.54's since originals have become so hard to find.

 

Man, it's weird... Looking at the pictures above I can almost smell gear lube. Yuck!

 

MMmm...sardines!

 

good stuff!