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  View original topic: How bad did i screw it up?
A1Tunaboy Sun Jan 26, 2014 1:41 pm

Trying my best to be a mechanic, I replaced my jumping out of 4th gear transmission last year for a Freeway flyer from Rancho. (Only took me three tries to get the axle flanges to seal properly.lol) We have barely driven Louie, (our bus) maybe only accumulating 500 or so miles since the install.
We were on one of our club cruises and almost made it back home, when we felt a large lurching or binding from the rear end with a lot of bad noises when I was down shifting. I couldn't get it to duplicate the noise, so we limped it home and I tore into the reduction box that I figured the noise was coming from. As suspected, I chewed up a the upper inner and outer bearing in the reduction box.
I anticipated that a bearing was bad, so I purchased all four bearing to be replaced when I got into it, but now I need your opinion on how bad the axle shaft, the upper gear and the outer cover of the reduction box.
I have yet to crack open the other reduction box to check it.
Also, since the reduction boxes and transmission share the gear oil, did I also screw up my new transmission?
All comments are welcome on what I should replace, just add some useful criticism with your post.







sled Sun Jan 26, 2014 1:46 pm

I would not use any of those parts, including the axle.

I doubt that much debris made its way back into the transaxle case but a complete flush is obviously needed.

Eric&Barb Sun Jan 26, 2014 1:59 pm

Doubt it was your fault.

You are going to stumble now and then!

When hearing expensive noises it is often better to get a tow (AAA) home or pull over and fix it there.
Personally have replaced the bearings in one 1955-63 RGB in just two hours in a rest stop just North of Redding CA. Helps to have the spare parts and tools on board.

Looks like you can save the inner RGB half, axle tube, and maybe the stub axle, but everything else will have to be replaced.

Transaxle and other RGB should be just fine. To double check this inspect the magnetic drain plugs from the center section and other RGB. If no shavings it is more than likely fine.

BarryL Sun Jan 26, 2014 2:36 pm

Before I can answer I need to know two things:

Is the circlip groove still intact and usable?

If you set the new outer upper bearing onto the axle does it still have a resonable amount of interference fit or does it just spin?

Stocknazi Sun Jan 26, 2014 5:02 pm

so what could have caused this guys bearings to explode?

campingbox Sun Jan 26, 2014 5:32 pm

StockNazi wrote: so what could have caused this guys bearings to explode?

Maybe the circlip to hold the crown gear and axle inside the transmission did not get replaced? Maybe the spacer behind that circlip was left out? Usually the end of the axle doesn't chew through the reduction box outer half like that.

That axle is done.

novetti Sun Jan 26, 2014 5:34 pm

Ouch

I can't see the circlip ring groove in the tip of the shaft to hold the bearing and gear.

Did the ring snapped off allowing the whole to axially thrust against the inner bearing / rgb case on the other direction?

A1Tunaboy Sun Jan 26, 2014 6:58 pm

I did a little more digging. I drained the Transaxle. There was shavings on the magnetic plug.
I drained the other reduction box, the magnetic drain looked good.
Also, on the bad RGB, the half axle does not spin freely. Surely, the inner bearing is gone.
I was going to replace all four any ways.

I am guessing what happened was the circlip did not stay in place and allowed the axle to move in and out. Circlip also got involved in the bearing and breaking down the outer and then the inner.
Pretty much now novetti explained it.

I do remember when I did all of this last year, that when I was removing the outer half of the reduction box on one side (I cant remember which side) the circlip that held upper outer bearing on the axle came off and the upper outer bearing was left in place inside the removed rgb half.
I cleaned out the groove for the circlip on the axle with a real thin file and made sure that the circlip was seated real good, but I did not use a new one. Looks like the circlip possible had lost some of is spring or spread out or the grove just did not have enough lip at the end of the shaft to hold the clip.

I am going to pull the entire rear axle out and start over. Was hoping to get some project around the house done before it started getting to hot. Oh, well.

So, there is shavings and debris in the transaxle, what do I do?
Can it be flushed sufficiently enough that it doesn't require a rebuild or am I wasting time?
Where can I find an axle and upper gear?
I haven't inspected the lower gear, if it looks good, I will reuse it, or am I wasting time again? These gears seam to be very robust. If the face of the upper gear didn't get messed up against the bearing, I would probably have reused it too.
Can I reuse the outer half of the rgb? I did get some damage but it did not do anything to the upper outer bearing seat, just behind it, and it only damaged a mm or so.
Thanks for all your help with my issues.

campingbox Sun Jan 26, 2014 8:05 pm

There are replacement axles for sale in thesamba classifieds. I think we have a few up, I have apile of them here. Ditto with the upper gear. Replace it. I would reuse the stub axle if it looks fine and the outter box half - assuming the retaining pin fits in there tightly. It might be tough to get the rest of the bearing out of there. I wouldn't worry about rebuilding the trans, drain the oil and refull it and call it good.

novetti Sun Jan 26, 2014 8:18 pm

Reading again and having a better look :

-The mark in the RGB cover is from the tip of the axle thrusting againt it.
Are you able to move the axle in / out by hand?
I would pull the side cover, daisy seal, that big circlip and crown gear just to be sure. Check everything.
You might have issues with the crown gear, fulcrum plates, axle spade or the big circlip retaining the crown inside the differential body because having the axle touch the inner side of the RGB has to be something in there allowing it to move in / out.

Don't need to drop the tranny to do the job, I just did that just a couple months ago with it in situ. Just use a thin spanner to reach that lower 13mm hex behind the frame and the side cover plate.

Debris from RGB wouldn't travel to the centre of the gearbox.

Lower gear looks fine, the top gear might even be reused if you get a good machinist to face grind it and make a space ring you could use to overcome the loss of material. If it is within specs might not even require it. It is not complete junk if you have access to proper machining services available to you.

jmmj Sun Jan 26, 2014 8:47 pm

novetti wrote:
Are you able to move the axle in / out by hand?


WAIT!!! if you pull on the axle you can provoke a whole new problem - one of the fulcrum plates can fall in behind leaving you with a &%$ of a job that probably wasnt necessary.

But Novetti is right, its possible it already has a fulcrum plate fallen behind which means the shaft wont sit in deep enough. You will have to do a search on this in relation to the rgb housing because my experience with this is bug only. Its possible that with a fulcrum plate in behind the rgb case wont even go on.

Good luck!

Cheers,

.M.P.

novetti Sun Jan 26, 2014 9:05 pm

jmmj wrote: novetti wrote:
Are you able to move the axle in / out by hand?


WAIT!!! if you pull on the axle you can provoke a whole new problem - one of the fulcrum plates can fall in behind leaving you with a &%$ of a job that probably wasnt necessary.

.M.P.

Fulcrum plates, axle and crown gear are retained in place by the thrust washer and the big circlip retainer. It won't fall off, only after circlip retaining the thrust washer is removed(which is a bitch to remove even with appropriate circlip pliers).
If the fulcrum plates already felt behind axle spade with circlip and thrust washer in place, it means axial play tolerance is already out of spec (excessive wear on spade, crown gear, thrust washer, fulcrum plates).

Clara Sun Jan 26, 2014 10:46 pm

I had a similar thing happen with a big nut box in my 61 bus.

The upper outer bearing was toast, it fell apart like yours.
The circlip groove on the axle shaft was completely gone, and I had to replace the shaft. Which meant I pulled the axle tube off, pulled the tranny. It had been whining a few years, so I figured I'd just get it rebuildt at that point.
I reused the gears though. They did not get chewed.

I knew there was something funky getting going in there, but when it started sounding rumbley I was a few hundred miles from home.

FWIW, it is normal to be able to slide the axle in/out by hand slightly with the inner & outer bearings and upper gear off.
You can have a fulcrum plates slide out of place if you pull it out all the way.
But that axle shaft doesn't seem to have a nice circlip groove anymore, so you need to get in the fp area anyhow when you replace it.

outer rgb bearings from when it happened to me:


This picture is fun:

cru62 Sun Jan 26, 2014 11:23 pm

Clara wrote:


Anyone else notice the awesome floor mats in Clara's shop? NIIIIICE!

BarryL Mon Jan 27, 2014 9:36 am

The face chew on the gear is not that big a deal as long as there is still meat to space it between the inner and outer inner races as that's all it does. It kinda floats in between there with supposedly zero side play but all that holds it is the circlip interference to the inner race. You can flip the top gear around, too.

The beauty of the RGB is there is not the huge weight of the bus on the top axle bearings.

Outer box is fine to reuse just ditch the abandoned outer race. What concerns me is the brake-holder/adjuster-alignment-pin might not seal since it's been removed.

The gears will make a tad more noise but that should get better with age. Any chips will have to be cleaned out on that side, of course, and all bearings new, reseal freeze-plug, new seal.

Just drain and refill the center section.

IF you can clean up the circlip groove and the scored axle will hold the inner race fairly then I'd reuse it as is.

I chewed off a circlip once which devoured similarly your predicament while on a long trip. I opened the cover, cleaned the snot out of everything in place, tossed the outer bearing and put it back together without that bearing and clip and made a paper shopping bag gasket. I drove another 50,000+ miles till finally replacing the whole transaxle. Upon breakdown the Gypsy Patchjob was still going strong.

Of course I know this to be a hokey patch.

davebuckholts Mon Jan 27, 2014 11:11 am

cru62 wrote: Clara wrote:


Anyone else notice the awesome floor mats in Clara's shop? NIIIIICE!

Yep, I noticed. I also noticed it looks as if Clara likes to break things......



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