The Stovebolt Site Forums The Shop Area Driveline Setting up a 4:10 Eaton

Just wondering if I should go a little higher on the backlash for used gears...got backlash of about .007 drops to .005 for some teeth. Should I go another notch on the right/left side nuts - seems a notch moves it about .002 roughly.

Heading off to GM for some gear marking compound. Hoping I'm close...I put it back together as original but who know what original was...changing out these pinion shims is going to be a PITA.

There's two possibilities for setting up used gears without building in a whine- - - -slim and none! Unless you ran a tooth contact pattern for reference purposes before the gears were removed and reassemble them to exactly the same relationship, there's going to be a new "wear-in" and almost a 100% chance of noisy operation. Good luck! BTW, plain old rattle can enamel spray paint makes a good gear-marking compound for checking the tooth contact pattern. I use semi-gloss white.
Jerry

When taking apart a closed rearend to service it, is it not the same situation as above? Would measuring the backlash before starting and then duplicating it do the job. I am thinking about the case when it is taken apart to service the bushings at the front, assuming the use of conventional separate bushings.

guess I'll have to turn up the radio LOL. I didn't measure the backlash on this when I took it apart, that was a mistake.

GM gear marker was only around $5 for the tube. I bought some cheapo lipstick to try it on the advice of bro-in law- and it didn't work so well.funny tho buying it at the store (wife did not want to donate)..I told the sales lady I wanted something cheap and bright to work on a rear end, LOL. what a look I got.

Probably the same sort of looks I get when I walk into a fabric store with a micrometer and start measuring the thickness of cotton denim material! I make round ball patches for my target muzzleloading rifle from denim, machinist's soluble cutting oil, and water. A couple of thousandths' difference in patch thickness or half a grain of powder weight makes a huge difference in the accuracy.

Checking backlash on a torque tube rear axle before tearing it down is a good way to assure it gets reassembled correctly. Also doing a tooth contact pattern is even better. I bought a 1-lb. can of white lead pigment on Ebay recently, which will be a lifetime supply of rear end checking dye and also lubricant for the dead center of my lathe. I mix the pigment with linseed oil to make a thick paste for both applications. The 3 tablespoons of white lead I'd been using for the past 20-something years was getting a little thin!

Jerry

Jerry,
I have always been curious about this point. In my old 38 manual it shows how to take the rearend apart to get the driveshaft out and then talks about setting up the backlash when putting it back together. So I guess the very best way would be to do the contact pattern and take photos of it before disassembly.

Fred

Be sure to do a thorough job of degreasing everything before trying to run a contact pattern- - - -indicator dye on oily gears doesn't show up well. I've used paint, Prussian Blue, and White Lead as a tooth contact medium- - - -White Lead is by far the best choice if you can find it.
Jerry

We used to use white lead to cover caulking seams in lobster boats before we went to bondo!

Should have saved a can or so.

My machinist buddy just called me and has a tube of Prussian Blue as well for me. I may try that as well.

Antique collectors love the artwork on old Dutch Boy white lead paste cans- - - - -I like the stuff inside! I'm bidding on an Ebay auction for a 1/2 full 5-lb. can of the stuff, which I'll be happy to empty and resell the can! Even if it's hardened into a solid lump, a little work with a mortar and pestle and a few drops of linseed oil, and it makes excellent lathe center lube!
Jerry

Anyone know where I can get a shim pack for a HO52? I need to adjust the pattern.

You've got one shim, right? As a last resort, use it as a tracing pattern and cut some shims out of .002" brass stock. With a good pair of sharp scissors, the outside shape cuts out nicely. A utility knife or something similar and a little persistence will handle the inside contours. If you happen to have a set of gasket punches, bolt holes are pretty simple, also. Stack up the shims as necessary to adjust the tooth contact pattern, That 5-hole pinion carrier casting adjusts in and out pretty easily, and the shims aren't terribly hard to fabricate if necessary. The mid-1950's Ford rear end pinion adjusts the same way, but I believe the hole spacing on the shim is a little different.
Jerry

Just for fun I checked the backlash on the 2 4:57's (1952's) I have here out of running trucks...both were over .20 and one was closer to .30! Considering factory is .005 to .008 that is a tad off. It was very hard to get a pattern on either, from what I saw it wasn't near optimal.

Talked to a local older truck shop here and they said they pretty much stick it together and run it LOL..The old boy said good luck getting a decent pattern on used Eaton gears..I don't think they spend much time trying to set up used gears...they put them back together with the original shims and spacers and away they go.

to each their own I guess....

That's over 3/16" to 5/16" slop in the gears Randy, don't you
mean .020" to .030"???? With that much slop they'd be on the
verge of skipping teeth.

DG

oops ..good catch Denny....missed a zero...I'll get heck from my machinist friends for that...

but still quite a bit of slop relative to settings in the 1952 manual...I guess these old girls can run outside of the envelope LOL.

That excessive backlash comes from wear on the gear teeth. That's why I said you're not very likely to get good results trying to set things up to factory-original specifications. The most obvious indicator of excessive backlash is a considerable amount of free play when turning the pinion yoke. If you're considering buying a complete unit and the owner doesn't want to open it up for an inspection, the free movement of the yoke is a good bargaining point on price. Don't assume excessive slack can be adjusted out!
Jerry

Thanks Jerry..I've been talking to a few older (bigger) truck guys here and the consensus seems to be put them back together with the original shims, check your backlash, adjust side nuts and run em'..don't bother chasing a pattern on older used gears, they don't appear to generally do it..I had one guy tell me it was a waste of time on something that old, that was for newer stuff.

Appears to be - if they howl, then deal with it. Add shims or turn up the radio.

It was funny, bought a tube of gear marking yellow from the local GM dealership, they could not remember when they sold one previously LOL.

I just bought a half-full 5-lb. can of Dutch Boy white lead pigment. It's dried up, but a mortar and pestle and a little linseed oil will give me a lifetime supply of checking dye, plus all the lathe center lube I'm likely to ever need. I already had an almost-full 1-lb. can of the stuff.

All the environmental wackos can now commence to get their panties in a wad- - - -I'm using that evil lead! The thing is, there's absolutely nothing better for either purpose! Just to really hack 'em off- - - -I also cast and shoot lead bullets, and cast my own lead fishing sinkers!

Jerry

So Jerry..is it worth chasing the pattern on gears this old, given the work involved with swapping shims? Whats your opinion?

BTW, I used lots of white lead..we used it to cover the caulked seams on lobster boats before we went to bondo.

I'd suggest getting the backlash somewhere in the ballpark and doing a test drive to see how much noise you end up with. If you don't see a fire engine in your rear view mirror, it's possible the siren behind you is actually the rear end gears! Seriously, a little gear whine doesn't concern me unless it's coming from a brand new gearset I've spent a lot of time trying to get exactly right. I listened to a whine from a Dana Type 60 in my 59 Burb all the way from California to Tennessee, and for a couple of years after the move. The backlash didn't change in about 5,000 miles, but it was a little noisy all that time. That one had a GMC housing, Ford gears, and Dodge pinion flange- - - -all junkyard parts!
Jerry

This what you bought Jerry?
http://www.pbase.com/dennygraham/image/154650675

DG

Yep, that's it- - - -90% lead carbonate, 10% Linseed oil. The stuff is usually dried up into a solid mass, so I dig some pieces out with a wood chisel and use a mortar and pestle and linseed oil to grind it to a smooth, thick paste. It makes the best lube for the dead center on a lathe I've ever used, and it works better than Prussian Blue for indicating gear tooth patterns.
Jerry

we used to go through tubs of that on the boats. Not a bit of protective gear.

Ah yes, no protective gear, that explains it Randy, we've been wondering.

Tisk, tisk
DG

I gave up living dangerously in the early 70s.

I'll continue to use Prussian Blue because it is prettier and safer.

So far it has been good enough for my 1950s-era truck gears.

ok..I won't get into the asbestos them.....

now I am intrigued...how is tisk tisk different from tsk tsk?

i(e)nquiring minds want to know LOL....

Tsk-tsk, pronounced tisk tisk, is usually an interjection
meaning shame on you, you've been a naughty boy. It also
works as a noun referring to an expression of disappointment
or condemnation toward someone.
And now your admitting you came in contact with asmostos, triple
shame on you. Next thing we know you'll be telling us you washed
your truck parts in Ethel and played with mercury in the palm of
your hand.

Wait a minute.... I think the guy in the mirror just gave me,
the Forefinger Rub.

Amazing what we used to get away with years ago before OSHA
started looking out for us.

I don't think Jerry's old school white lead will be the death
of him, surely couldn't do any more damage than he's already
suffered.
But seriously, a white foreground with a dark scratch on it
would give you the absolute greatest contrast. I've used Dykem
both red and blue and it's true, you don't get a very positive
read on the teeth. Wonder if the commonly available oils
titanium white and such would give you a read similar to the
white lead?

Denny G

Yes, for the PC bedwetters with the lace on their panties artists' Titanium White pigment would work just as well as a tooth contact indicator- - - -just don't try to lubricate a lathe center with it. If smoking 2-3 packs of Winstons a day for 40 years and crashing various race cars and dirt bikes hasn't put me underground, I doubt if being exposed to a few grams of lead compounds is going to make much difference. If it does, then it was my choice to expose myself to the mythical hazards. The people who are dedicated to minding my business instead of their own can take an airborne fornication at a rotationally-motivated piece of pastry!
Jerry

Mercury? that one one missed me, but just barely. My older brother and his buddies used to play with the stuff at one of the many old abandoned gold mines here, apparently it was used it for gold production and it was just left laying around the old tailings..

...and they did play with it in the palm of their hands.

Now my old man did have a thing for Mercury, but that ws more of the pick up version....

Now regarding the rear end, I bolted it all back together yesterday..it will be interesting to see how this rolls out. There was a a couple of thousand run out in the ring gear so setting up the thrust bolt was a bit tricky, not sure how much difference it will be as this will not be used heavily.

Yep, wouldn't mind finding a thimble full of that white lead
next to my little Logan. I just use some way oil in the
dabber but that gets worked out pretty quick.
http://www.pbase.com/dennygraham/image/154661861

Not to worry Randy, you're never gonna put that kind of stress
on the rear end. Just bring the bumper up till it touches the
ring gear at the high spot and lock her down. even if it
touches it a tiny bit no problem it's brass tip gets plenty of
lubrication.

DG

I have a rear-end to do as well. Seems like white would show the best. Would white lithium grease work as well as the other methods?

A small tube of artists' white oil paint pigment would be a good substitute for white lead as a tooth contact indicator. Any art supply store should be able to provide that. I believe the name is "Titanium White" like Denny mentioned. It's also mixed with linseed oil to a workable consistency.
Jerry

Jerry is the expert here Scott but I wouldn't think you would
get a good read with it. Grease, even lithium grease is
semitransparent when spread real thin. The white lead or
titanium white would work well because even when spread very
thin they still cover very well.
I've got to dig out the 4.10 I got for my '54 and give the
titanium white a try. But as the man said it taint gonna be of
any use at the lathe.
DG

As always, thanks for the advice.