Hairball Medicine (Differential Fix)

[LBRC]

http://lbspd.com/v-web/gallery/albums/album58/MVC_372L.jpg

Your differential prone to hair balls? This little mod will allow you to clean when needed.

http://lbspd.com/v-web/gallery/albums/album58/MVC_377L.jpg

First you have to remove the retainer. Do not try to pull or twist it off you will bend the axle and strip the right rear wheel. Simply squeeze it with a pair of pliers then rotate it 90 degrees and squeeze it again, repeat as necessary until it easily pulls off.
http://lbspd.com/v-web/gallery/albums/album58/MVC_380L.jpg

Clean your differential and apply a light coat of silicone grease or synthetic oil to the gears.
http://lbspd.com/v-web/gallery/albums/album58/MVC_382L.jpg

Reassemble the differential.
Use a jeweler’s knife edge file to make a shallow grove around the axle flush with the edge of the differential. Take care not to make the grove too deep, better too shallow at first since you can always make it deeper if needed.

[LBRC]

http://lbspd.com/v-web/gallery/albums/album58/MVC_383L.jpg

Then use a 1/16” E-clip to secure the differential.

I used a rotary tool to spin the differential shaft while cutting the grove with the knife edge jeweler’s file, this way the grove was perfectly round allowing the shaft to spin if for some reason the E-clip where to catch while the differential was operating.

The placement of the grove is vitally important the portion of the differential that holds the wheel must spin free of the axle for even differential action, but that same portion must also remain firm against the gears. By making a perfectly round grove and using a round E-clip like the one in the photo the clip will be able to turn and the axle will also be able to turn if needed. Even if the clip is too loose the wheel will keep it from coming off.
http://lbspd.com/v-web/gallery/albums/album58/MVC_389L.jpg

Once you have successfully completed this mod the E-clip can be removed and the differential disassembled for cleaning whenever needed. It is not necessary to remove the axle from the motor mount in fact you should avoid doing so.

[arfin]

Hey LBRC, i did it cleaned 2 Diffs, MAN this is the greatest mod ever, your the greatest LBRC!! :D :D

The steps i took are:

1.Take the motor out.
2.Pry the wheel beside the diff out a bit, for better grip
3.Then like LBRC said, squeeze the diff, and turn the wheel. You will hear a noise, and that's when you know it's coming out.
4.Once it's out find all the hair and take it out, my hair was located behind all the parts, in front of that one gear that doesn't come off.
5.Reassemble, and push the wheel back in, if you pushed it out.

Now you have a diff, almost as good as new. LBRC, do you think Home Depot carries that E clip?
Also don't forget to squeese the wheel back in, thats if you needed to squeeze it out a bit.

[LBRC]

I’ve managed three cars so far without taking anything more than the wheel and body off.

All you have to do is give the retainer a good hard squeeze with a pair of pliers, then let up move the pliers to a different spot on the retainer (90 degrees out) and give another hard squeeze, repeat as many times as necessary until the retainer loosens up and slips off. It usually takes me 5 squeezes using the flat spot close to the base of a set of large needle nose, when using a small set of needle nose pliers with a cutter so that I had to use a higher spot on the pliers with less force it took up to 20 or so but I just keep it up, squeeze let up rotate – squeeze let up rotate, until it deformed enough to easily slip off.

Home Depot maybe but I sort of doubt it, the one here doesn’t have much in the way of uber small parts, I picked up the ones I’m using at a local Ace Hardware.

[LBRC]

Update: If the E-clip touches the side of the wheel use a drill bit the size of the outside E-clip diameter to clear a little space.

If done correctly this mod is a vast improvement over a hair and lint clogged differential, but there is always room for improvement. So for some of my modified cars I wanted more.

A better version would have an ultra smooth spacer the diameter of the retainer that could fit loosely between the E-clip and the differential but thick enough to keep the differential from touching the E-clip.

That would be good, here’s something better.
http://lbspd.com/v-web/gallery/albums/album58/MVC_394L.jpg
Yep, a ball bearing :cool:

[arfin]

Damn your mods are all amazing man! Where did you get a bearing that small? Any specs on it, i'd like to get one. Thanks!

[LBRC]

The bearing is easy it’s one of the two gear case bearings from a MZM upgrade kit. Carefully enlarging the hole for it to fit is not so easy, I hand drilled out the hole with a 4mm bit, lol and a whole lot of checking and patience.

[arch2b]

The bearing is easy it’s one of the two gear case bearings from a MZM upgrade kit. Carefully enlarging the hole for it to fit is not so easy, I hand drilled out the hole with a 4mm bit, lol and a whole lot of checking and patience.
epoch might be able to get bearings to fit, what is the stock opening size? would an overland bearing for the main gear housing for example be small enough?

[LBRC]

epoch might be able to get bearings to fit, what is the stock opening size? would an overland bearing for the main gear housing for example be small enough?

Should be the exact same size as the Mini-Z Monster bearing I used with a 4mm outside diameter. The differential hole is 3.5 mm and the retaining bead is 3 mm. I suspect it would be almost impossible to find a bb with a 1.5 mm inside diameter and 3.5 mm diameter since it only leaves 1 mm for the balls and races.

I have a track set up outside on a raised platform in a garage tent still a work in progress but now functional, it uses foam mats coarse sanded for a RCP like surface covered with a light coating of chalkboard paint, the 3/4" rails have a plastic/Teflon face with foam backing. After a night of driving the bb is definitely the best way to go. I cleaned 5 differentials in under 15 min this morning :cool: and was surprised at the amount of dirt, lint, grass, hair and who knows what else they collected in just a few hours outside on a clean track, inside would have been worse inside with cats and dogs.

[arch2b]

how do you like the chalkboard paint surface? i've often thought of that myself but never tried it.

[LBRC]

Terrific :D

A 60 or 80 grit scuffed foam surface with a light coating of chalk board paint is a must try, especially for smaller and narrower tracks.

I no longer have room for my larger track, so I needed something to replace it with and since it would be outside even thought covered by the tent it had to be something that could be cleaned, repaired, and disposable if need be. I had built some cars for a couple of US Navy types who where going on deployment and had purchased a very large Lakeshore set up to take with them, it was the first one I had ever seen so I assumed that their set-up was what you got when you ordered one, wrong. They had sanded the surface, sprayed it with the chalk board paint, and made inserts to fill the gaps in the rails, a real pro job but then they had the equipement and manpower. So the joke was on me it wasn’t until much later that I learned what they had done to turn a horrible track into one of the nicest two foot lane portable tracks I have seen. So for my outside track I purchased old LS tiles (dirt cheap there owners hated them) and have been slowly sanding the surface down and coating it with chalkboard paint, then adding a Teflon coated plastic edging to the rails that also covers the gaps. The finished track will be 20’ x 10’. One great thing about the paint is that for a semi-permanent set-up you can tape the connections and then paint the tape, perfect for Epochs and smaller modified cars.
http://lbspd.com/v-web/gallery/albums/album44/MVC_233L.jpg
It's also a very good looking surface, the finished track will have lanes as well as EL-wire edge lighting. I like it so much I’m almost tempted to try a light coat on the RCP surface for the larger cars but that would render it useless for competitive practice.

[epoch1-43]

LBRC, let's see some pics of the track; you need to start yourself a Member Album:

http://epoch1-43.com/gallery/showmembers.php?cat=500

:)

[arch2b]

yes, i would love to see a new thread on just your track. i could go on but i'd rather save it for a new thread rather than take this one off track. please post more pictures (see member gallery) and details :p