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Cleaning a diff assy

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blkcorvair

Jedi Knight
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I picked up a good used 4.2 diff, but it was shipped in a box with papers and cardbord. Now there's little bits of cardboard and whatnot sticking to various parts inside the diff. I blew most of it out with compressed air, but does anyone have any ideas what I could flush it out with. I heard mineral oil but not sure. It will be installed dry for about a month before I get my new hubs, so I dont want to leave it un proitected. Maybe I could drown it with some 80/90 after I clean it up.
 
Flush it out with mineral spirits, followed by compressed air. Let it dry, pour some 80W90 on it, rotate it to distribute the oil, put it in and forget it.
Jeff
 
I would put it in a 5 gallon bucket and cover it with gas and let it soak for a while and turn it a bit to help clean off the gears and avoid sparks and flames /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
While out, If you have someone who is knowledgable, you, might check it for play and shim it. Maybe someone could give us a tech lesson.
 
The backlash varies with each gearset, and is etched on the back of the ring gear. I'm looking at one for a 4.55, and the backlash figure on it is .006"
While properly setting up a diferential is far from rocket science, it does require some special tools. A <u>good</u> dial indicator with a solid mount is a must. A decent set of Vee blocks is a plus.
Jeff
 
""""""I picked up a good used 4.2 diff, '""""""


I assume this is for the car your building? and not for stret use ?

At a a minimum I would check the backlash on the gears (get a number), remove the ring gear carrier, and pinion assy and the seal, wash the case, inspect everything, put in a new pinion seal, give the goofy lock plates on the ring gear bolts the flotation test, and use loc-tite or drilled head NAS screws and safety wire on the ring gear. Watch the under head radius if you use NAS and then use beveled i.d. ground flat washers.

On the caps use hardened washers and new ARP or grade 8 nuts with loctite. Get rid of the lock washers. They tend to damage the original nuts when removed. once you do all this you dont have to worry about it.....cause you did it right. not a pleasant sight when the bolts back out.

Whatever you do., do not use gasoline to wash off anything.

You don't want to get any solvents in the pinion seal cavity also. When you remove the seal it will be hard as a brick unless the p.o. has replaced it in this century. you can also clean up the outside of the case real nice and remove any paint. In your spare time you can polish it also...:smile:<)).
 
yes I think its under control. Was a very good looking piece. Got it from W.C. at a reasonable price. I try to locktite everything. (Ive seen bolts back out for no reason. no good.) As for cleaning the unit up. I found mineral spirits worked perfectly. New seal. Ditched that paper gasket though. Used some gray Yamabond. Never failed that stuff before.
 
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