RepairingPolishing Differential Ring Gear

The differential side carrier plate and spacer failed on my 512BB recently leaving the pieces inside case and leaving the differential free to walk around until I had time to get it out of gear.




The ring gear appears to have been damaged as well as the differential itself.





The box has been sent to CA for rebuilding. I was wondering what the prospects of saving the ring gear were as they are very hard to obtain?

Appreciate you comments.

Drew Altemara

I could see it being possible. Not ideal but possible.
You can see where the teeth mesh togethor (the non varnished areas)- your damage in this picture seems to be on the top edge only.
That being said it would require some very particular clean up and measurements to make sure you're not going to be putting wear on the mating teeth.

Best of luck.

If you decide you have to have a new ring gear it could be possible to reverse engineer one.
I have had this done in repairs of industrial gearboxes where getting OEM parts was not readily possible.

Drew,
I dread to think what might have been the outcome had the carrier plate decided to let go when you were doing 100mph, or more, instead of the 5mph that you were actually doing.
Obviously the 'last straw' or final push, was the extra activity in the diff gears, while you were taking the left turn.
If you were to stop and think about what 'CAN' happen you probably wouldn't get behind the wheel.

How is the progress?

We have the transmission seperated from the engine and crated up. I am told there are no ring and pinion sets for these cars any more. Fortunately, Ted Rutland bought a used 512BB transmission. We crated this up along with mine and sent it to CA (Ron Drew). Using some parts from Ted's transmission he will repair mine. Of course we'll replace all the syncros and seals along the way. When we're done Ted will inventory the used parts that are left.

In the mean time we're doing the belts (been 6 years) and I'm a 5-7 year timing belt guy, tensors, water pump, hoses, etc, etc, etc. Everything you should do with the engine out.

Hope to have it back together this summer.

I really miss this car. I have a Daytona to drive while this one is being repaired but I actually like driving the Boxer more.

Don't tell the Daytona guys.

Will keep you updated.

Drew

Drew,

I'll make a few calls for you...I think I may have a source for a new ring and pinion. I'll get back to you Monday afternoon.

Regards,
David

Thanks David. Appreciate any help.

Drew

Drew, sorry to see this!!

yes, it appears most of the damage on the RG is outside the wear groove, no pictures of the pinion, and it might be possible to polish out the nicks with a dremel & stone, but you would definately need the R&P Magnafluxed to insure there aren't cracks that pics won't reveal.

Honestly since you've gone this far you might as well replace them and try to rescue the old parts for spares for someone down the line. Besises Magnafluxing I would also have the R&P X-Rayed to insure you could sell them later & feel comfortable.

The other issue you mentioned is the LMTD Slip Unit, I would have the Housing Magnafluxed to insure the integrety of the housing & welds, and maybe even run a double weld. The Welded Units were what failed on the TR's which blew out the side covers something simular to your pics,until the newer version 512M unit came out that was a solid housing without the welded end.

This is the fist time I've seen this on a Boxer but the Damage looks almost Identical to several TR side cover explosions I've done that were caused by the LMTD Slip Housing welds cracking, causing the unit to expand/blow outwards.

Thanks for you comments JR. It makes me feel more secure getting a good second opinion.

We are going down the path you described. Ted Rutland came up with a used BB gear box. Rutlands has crated both transmissions up and is sending them to Rod Drew in CA. He rebuilds a number of TR boxes for Rutlands that they keep in stock.

The plan is to salvage the ring and pinion and maybe some of the differential parts from the used one that Ted found, repair mine and then Ted will keep the other good parts as spares. Pricing is open at this point but I've know and worked with the people at Rutlands long enough that I feel comfortable. Do not really have another choice unless David comes up with a new ring and pinion.

Along the way might as well replace the syncros, bearing and seals.

Again thank you for you comments.

Drew

Drew,

I found a brand new ring and pinion set...and left a message on your phone phone VM for you. Please give me a call when you get a chance.

Regards,
David

Drew - is this a different box/ r&p than the injected car? It worries me that such an integral part of the car is nla. Makes one not want to drive the car knowing they can blow out that easily with no warning and this hard to find, not to mention $$ to obtain if one is sourced. Sounds like you needed to pull the engine anyway for the major, so at least you are getting that sorted as a result of this unfortunate event. Still have the sodium filled valves?

Ted