RT4 bearing help

[lucky13]

I need to replace a front and rear bearing on a 1986 RT4 and am having a heck of a time.

Front - Honestly, I'm not sure I see how the stub axle and bearing come apart. There is a single snap ring on the inside of the bearing so I assume that I need to press from the outside in, but that I need to press out the stub axle and hub first. With the flare at the back of the stub axle and the threaded part of the stub axle being larger than the hole in the hub, I'm not sure what the correct procedure is for accomplishing this.

Rear - I've pressed out the hub and the larger snap ring, and attempted to press the bearing from the outside of the upright with no luck. I have been told that they're a bear and require heat and a LOT of pressure. I have put a good bit of pressure on the bearing (8k lbs on the gauge) but have been reluctant to add heat, assuming that this is a magnesium part. Do I just need to keep cranking on the press?

Thanks in advance for any help.

[Thomas Wirtz]

Heat is your friend when removing / installing wheel bearings in a Magnesium wheel bearing carrier.
BUT, you need to use a electric heat gun similar to a hair blow dryer. Often used for removing paint.
Apply the heat on the bearing carrier and the bearing will easily come out with a little pressure.
Use leather gloves while heating and handling the heated wheel bearing or you'll soon realize you should have worn gloves. The same goes for installing the wheel bearing. before installing the new wheel bearing place it in the freezer for a couple of hours before heating the wheel carrier, you'll find the the frozen bearing will almost drop in the heated wheel carrier.
best of luck.

[Bob L.]

don't know if similar, but my RT5 (SV) had some jack screw holes to use during disassembly...do you have anything like that on front/flange side? Been a while since I had them apart, would have to go back and look for procedure, that came from Ralt. As I recall, there are jack screw holes in flanges, then you remove the carrier with brgs/stub axles..... On flanges, supposed to use 10-32 screws from assembly to jack apart, but I ran out of threads before flange came off...had to use longer screws w/ shims and heat to get apart. Was touchy. Don't recall all the detail on carriers, but think I had to make piece to press them out...from outside to inside. Once out you took brgs out of carriers.

Can look for written Ralt procedure if you'd like, Would need to scan, it that is working. Send me email to forward scans of those..if you want, may not be super quick.

Did need heat to put back together, I bought oven from rebuilt place for shop to heat the uprights....then pressed. Took some tooling to press stuff in, keeping things square.

Also, took big snap ring pliers to get those out. Had to take care with snap ring groove in upright, land was easily damaged when reinstalling brg. carrier as all was up a deep hole with cooling on upright and no good visual. Think I used old brgs as tooling to reassemble. Easy to damage seals/shields on brgs.

Bob L.

[lucky13]

don't know if similar, but my RT5 (SV) had some jack screw holes to use during disassembly...do you have anything like that on front/flange side? Been a while since I had them apart, would have to go back and look for procedure, that came from Ralt. As I recall, there are jack screw holes in flanges, then you remove the carrier with brgs/stub axles..... On flanges, supposed to use 10-32 screws from assembly to jack apart, but I ran out of threads before flange came off...had to use longer screws w/ shims and heat to get apart. Was touchy. Don't recall all the detail on carriers, but think I had to make piece to press them out...from outside to inside. Once out you took brgs out of carriers.

Can look for written Ralt procedure if you'd like, Would need to scan, it that is working. Send me email to forward scans of those..if you want, may not be super quick.

Did need heat to put back together, I bought oven from rebuilt place for shop to heat the uprights....then pressed. Took some tooling to press stuff in, keeping things square.

Also, took big snap ring pliers to get those out. Had to take care with snap ring groove in upright, land was easily damaged when reinstalling brg. carrier as all was up a deep hole with cooling on upright and no good visual. Think I used old brgs as tooling to reassemble. Easy to damage seals/shields on brgs.

Bob L.

I overcame my reluctance to heat and the rear bearing popped right out. That ease with which it came out doesn't match with how much pressure I put on it without heat and got nothing but...I'm not complaining. I would really appreciate the Ralt procedure if you can scan copies. mbcmr@aol.com

Thanks!

[Bob L.]

Sent email with 5 pages attached....hope you get them. Bob L,

[lucky13]

Sent email with 5 pages attached....hope you get them. Bob L,

I got the stuff you sent, Bob. Thanks very much. Still working on figuring out that front but in time, I'll get it.

[Bob L.]

Have you removed the nut on outside of stub axle? Spanner type lugs way up the hole...believe with that off you can press the stub axle/assy. out the backside. I had to make a tool to get the drive lugs, as all was so deep, needed depth to clear stub axle, it threads down then hits threads for wheel, threads down those to get off....could send you a photo if you want. Nut is a std. bit from brg. store....

Bob L.

[lucky13]

Have you removed the nut on outside of stub axle? Spanner type lugs way up the hole...believe with that off you can press the stub axle/assy. out the backside. I had to make a tool to get the drive lugs, as all was so deep, needed depth to clear stub axle, it threads down then hits threads for wheel, threads down those to get off....could send you a photo if you want. Nut is a std. bit from brg. store....

Bob L.

I have removed the nut, yes. I have a tool with the four prongs sticking out one end and a 1-1/16" nut on the back for an impact socket. It sure does look like the outside thread diameter on the stub axle is larger than the hole I will be pressing into on the hub. I'll get another pic and send it.

Matt

[Jerry Poole]

What wattage heat gun are you using to heat the bearing and magnesium upright? Could you suggest the brand of gun you are using ? THANKS!!!! , Jerry

[Bob L.]

I used a cheap HF heat gun, on high setting during diassembly... you could add heat temp paint/sticks (welding store), keep under 450F, or so....don't want to melt rubber seals in brgs.... Use heat and press....

[Bob L.]

I have removed the nut, yes. I have a tool with the four prongs sticking out one end and a 1-1/16" nut on the back for an impact socket. It sure does look like the outside thread diameter on the stub axle is larger than the hole I will be pressing into on the hub. I'll get another pic and send it.

Matt

If nut came off, threads dia. must be small enough to go thru hub....or why have the nut on axle to flange? Only reason for nut: to secure flange to stub axle. There's a big thrust collar/washer on back side of flange...between outer brg. and flange. See photos I sent you, off forum. Keep things square while pressing.

Bob L.