themanimal

Ok, I’m by no means a newb but it seems that for the life of me I can’t get my kanai diffs to co-operate with me. It’s the front diff that has really been causing me problems. A worn out original diff the (TCLD or whatever) prompted me to install a standard diff. I ordered all the correct parts but keep chewing up parts. Here is the low down:

Installed everything identical to the initial set-up and wore the teeth off of the pinion after one day. I thought perhaps I shimmed it too much. Also thought perhaps diff case was getting worn out.

Put everything back together with new diff case as per the manual drawings. Seemed to have a good mesh but the whining and screeching told me otherwise. Tore everything apart, checked for drag brake, replaced the internal gears and fluid on all three diffs, checked wheel bearings. Replaced the drive pinions on front and rear.

In a very late night haste to get ready for a race I accidentally installed the thick washer between the inner bearing and the pinion gear...which caused friction, heat and a case meltdown. AAAAARRRRRRRRGGGGGHHHHHHHHH. I bought completely new bearings for the diffs, a new case, and I’m ready to re-install everything.

So.... the questions are.... 1st. Where does the thick washer go? It seems that it should go behind the inner diff bearing and the case. If I leave the washer out the pinion is too far back in the case to mesh well with the ring gear. The manual shows the washer but doesn’t show where to put it in!!! 2nd. When shimming the diff left and right..how tight should it be? Is a little play acceptable? 3rd. I’m using the diff case with the grooves on the outside, should I be using the smooth diff case with the non TCLD gears?. they seemed to fit well.

Any help would be greatly appreciated. In 3years of MT’s, stadium trucks and buggies I have never had problems like this before.

Jammin"145

Throw it in the river and buy a Jammin' Actually I need a new boat ancor so I'll take it.See ya Thursday at the track.

Cash-Money

i thought the kanai diff's were buletproof
i would just buy a pre built diff like the spider one from ofna

themanimal

Someone is itching for a beat down!!

I thought you had aboat anchor already? At least it's about as fast as a boat anchor.

Cash-Money

Cash-Money

i keep a dessert egale in my car at all times.

themanimal

ooooh aren't you tough with the gun in your car.

here's a tip douche bag. Stop spamming my thread. You obviously have no experience in this diff matter or any RC matter if your quoting ofna parts as bullet proof.

Jammin"145

It might only be slightly faster than a boat ancor but it least it will run all day,since it is a Jammin'.

themanimal

Anyone with any real help?

SpeedBump57

Ya know it is threads like these that give both cars a bad name.

XingXing

too hard to follow your post buddy.

pictures will help us help you.

but here is a tip. change the k3 bulkehead with a 777 bulkhead. thye are same part number but the 777 bulkhead are much stronger, so wont develop slop like the old 7.5's did.

themanimal

Actually, its threads like this that give RC posters a bad name. I'm looking for technical assistance.....

Xing xing..thanks a bunch for that tip! I'll order a new diff case next week. Don't have any pictures but I think I'm going to try and scour other 7.5 manuals for the diff details. The new pinion gear comes with a thick washer and that washer is listed in the parts list for the diff assembly insturctions but it doesn't specify where it goes!!!!!!!!

AreCee

iTrader: (1)

Don't know where you see that washer listed because it's not used in the 7.5 or 777 manual. Yes, it comes packaged with the pinion but you don't use it. What you do use are the large diameter thin shims on the outdrives to move the crown gear closer or further to the pinion gear to set the correct mesh. A thin spacer can be used between the pinion and its bearing to move it closer to the crown.

Once you have the diff shimmed in the bulkhead it shoud feel snug to turn by hand, that's OK because after you run it in the diff will loosen up a bit.

themanimal

Thanls for the tip!! I only put the washer in there as it seemed that the pinion was not meshing too well with the crown gear. I'll take another look today and see what happens when I take the washer out.

Just as an FYI though, if you DO put the wahser in FRONT of the bearing (between the pinion and bearing it will create friction and heat and melt the diff case. SO if you must put it in, put the washer in frst, then the bearing and then the pinion.


Thanks again for the "reality" check. Looks like anothe night of diff work

AreCee

iTrader: (1)

No problem. As I said, I don't use a spacer/shim on the pinion in my 777 but I did need to shim the diff on the crown side to mesh more firmly with the pinion. You have to check it occasionally to see if any slop occurs but that can be done without disassembly by trying to move the outdrives from side to side, if you can then shim again.