Transmission / Overdrive: Overdrive Problem

[joenj]

OK, I have a 1950 Champion 9G. It did not have overdrive. I traded for a 1950 Champion rust bucket that had overdrive. Removed transmission and replaced all bearings and seals. Inside looked good. (I have worked on standard transmissions before, but not overdrive) I have a shop manual and a manual from Randy Rundal on the transmission. I installed it in my good car and used a wiring harness from a Studebaker vendor. No problems with the wiring. My problem is the transmission will not shift in OD. Ran a extra wire from the Solenoid to the inside and connected it to a VOM. At about 30 MPH VOM shows 6 volts. Slow down and voltage drops to zero. (Governor and wiring good.) Checked Sol. and cleaned it. Still no OD. Tried a sol. from a working OD transmission of a friend of mine. Still no OD. Tried my sol. on his car, worked fine. In OD the transmission freewheels like it should. Lever on transmission is back all the way to the stop. Pulled transmission and disassembled again. Found nothing wrong. Back together again, and does not shift into OD. Does anybody have any ideas what could be wrong? Tried all the trouble shooting in the book. ( Put car on blocks and ran it to 35 MPH and OD solenoid buzzes and does not go all the way in.)

[joenj]

OK, I think I may have found my problem. The gaskets that I used are thinner than the old gaskets, causing the parts inside to bind. Has anyone else had this problem? I am going to try using more gaskets and see if that cures the problem. I have checked the parts inside thinking that I might have installed something wrong. Everything is in the right place. If the gaskets don't fix it, I don't know what to do.

[bezhawk]

The solenoid has to be put in correctly. Do not push it into place and instal the bolts. It MUST be twisted, so the flat spots on the shaft engage the pawl . Then you twist the whole thing to line up the bolts. If you remove the solenoid bolts, and hold the housing straight, you should not be able to pull it all the way out. If you can then you know that the shaft has not seated in the pawl correctly.
The reason for this is the shaft on the solenoid is shaped like a lolipop, and the end has to be able to PULL [on the pawl] when it's engaged. The pawl also has a circular cut out where the solenoid shaft rides

[joenj]

Thanks for the reply bezhawk. The solenoid turns 1/4 turn and locks in just fine. I checked it first thing after the trouble. To check it, all you half to do is remove the two bolts and pull straight out on the solenoid. If it comes out, it was not locked-in. To get mine out, you turn it 1/4 turn and pull out. I tore down the tranny today and could not find any thing wrong. Added 2 gaskets to both sides of the overdrive unit and reassembled it. Just put it in me car and now it works fine. I think the thin paper gaskets put a bind on the shift shaft. Also my governor does not shift until about 32 MPH. (Checked with GPS). Is that because of the rear diff. ratio is for a car without OD? I don't think this will be a problem. Has anyone did this before? Do I need to change the rear end? I have he whole rear axle in my parts car.

[StudeRich]

32 MPH for a Champion 169 sounds perfect, but I would look at the Tag on the Diff. divide the Pinion tooth count into the Ring Gear count.

A good number for Overdrive and today's Fuel Prices is the Standard Trans. Ratio, which may be 4.10 vs 4.56 for most Overdrives.

[joenj]

StudeRich, checked my ratio on my diff. It was 4.10. My parts car is a 4.56. I seem to not need any more power, so I am going to leave the 4.10 in my car. I can see the need for a slower rear end if I was loaded and in hills all the time. I have not had time to drive it much with the OD working. (just got it to working 4 hours ago.) I do not know how it will do at 70 MPH on the interstate. Before the engine seemed to be turning too many RPM at 70, that was the reason I added the OD transmission. It should reduce the RPM by app. 30%. Do most people leave the 4.10 in overdrive cars?

[TWChamp]

My 50 Champion has the 4.56 and I wish it had the 4.10. Your car doing 70 with no overdrive and 4.10 must have been ready to throw a rod.

[joenj]

TWChamp, It was. Only did it once, and seen I needed another gear. I don't have a tach. on it but I would guess about 4,000 RPM. The engine would not have lasted long.

[bezhawk]

Glad you got it sorted out. I think about 3OOO @ seventy would be about what you would want with a Champion engine

[joenj]

OK, Got all the bugs out of my OD transmission, and I love it. Adding 3 extra gaskets did the trick to let it shift right. Had a little trouble adjusting the kick-down switch. I can drive on the interstate with out over speeding my engine. Thanks to all you that responded to help me and to the search function on the forum. Randy rundle's book had a note about the gaskets that sent me to the right track and the info. on the forum helped with the rest. About wore-out the trans. bolts removing and tearing down the OD part of the trans. but learned a lot about how it works. Thanks again. Joe