can anybody tell me of a good shop in northern indiana or southern michigan where i can have these trannies rebuilt? I just want these to be pretty reliable i hear about alot of pump gear failures. thanks

There is someplace in Kalamazoo Mi. that does them,....get a hold of Crazyhorse he has had work done there, he gave me the name also but I can't find it right now,....Fred

that would work great i have a uncle in kalamazoo. thanks for the help.

I had a pump gear failure. I bought new parts from Bam Marine, and redid it myself. The hardest part was pulling the motor to get the trany out. He also sells an improved clutch pack for the Merc trans. I put that in just as a little insurance.

If I were you, while your trannys are apart, send out the pump gears and shafts to be Cryo treated. This process was unknown back when I was running the MercTrans and have often wondered if this could have solved the cracked pump gear problem

I`ve done a little research and I`ll be sending out my TRS gears, shafts and bearings to Diversified Cryogenics, the owner seems to be really intune with his trade and motorsports applications

Good luck,

Kurt.

Exactly right, Kurt! I did this about 5 yrs. ago after repeated failiers and have had no prob. since with 500+ HP. --- Jer

I WOULD TRY TO SEND TO HUBER TRANS. THEY DO GOOD WORK FOR ME !!

I have a theory on why the pump gear splits. We see the same thing on the bigger trannies occasionally and I believe it is due to the input shaft twisting. This causes the key to skew at an angle, and with very little clearance between the key and the slot in the gear this force tries to expand the gear, which then promptly snaps. We take a few thousandths off the key where the gear rides.

Cryo probably can't hurt, but not sure if it would help this.

Mbam, It`s been a long time since I ran the MercTrans. I had MANY pump gear failures over the years. My twin Gale Banks turbo BBC 24 Superboat had a tremendous appetite for them. I think the 29 Mirage had a lot to do with it!

If my memory is with me, on the pump gear wasn`t the key slot machined at the thinnest part of the gear? and your theory would prove correct, twisting of the key would put undue pressure on the weakest part of the gear.

Your fix makes perfect sence to me!

Kurt.