Overdrive questions

50C8DAN

My '50C8 is now running and I am trying to shake out the issues with the tranny. It shift OK and goes into OD but it does not seem to want to freewheel and I cannot get it out of OD (manually) until I slow down and it shifts out on its own. Anyone have any ideas? Also, it has Supermatic but I have it turned off.

Unknown

Dan: I am not familiar with Supermatic and what it does; is this some kind of shifter preselector or something? In any event, you seem convinced that it's not related to your problem. I had a similar experience with our '54 Kaiser and you might want to check several things: First, make sure your tranny and overdrive gearcases are full of 90-weight or whatever they are supposed to take. Next, make sure your kickdown switch is hooked up properly and functioning right, and that your overdrive solenoid is working good and not all gummed up or something. I have a 1955 Motor's Auto Repair Manual and there is a pretty extensive troubleshooting flowchart for this sort of problem. If you are handy with an electrical meter (volts/amps/ohms) you should be able to follow the flowchart and figure out where the problem is. If you do not have one or don't have access to one, Motor's manuals are all over eBay and you can usually get a good one for $15 to $25 depending on condition (I did). They are indispensible and I highly recommend getting one. -Tom-

Jon B

Dan: let me understand. Are you saying that, when in overdrive (fourth gear), you tromp on the accelerator and the thing doesn't downshift into 3rd?



You also say it does not want to freewheel. Are you saying it does not freewheel when in conventional gear (that is, before you have lifted your foot to shift into overdrive), when the dash knob is pushed in? It should freewheel then, but not once it's shifted into overdrive.



Just wanted to clarify the problem.

Unknown

50C8DAN wrote:

My '50C8 is now running and I am trying to shake out the issues with the tranny. It shift OK and goes into OD but it does not seem to want to freewheel and I cannot get it out of OD (manually) until I slow down and it shifts out on its own. Anyone have any ideas? Also, it has Supermatic but I have it turned off.

Hey there

I have a 1950C8 with supermatic. It´s in pretty bad shape but running. As far i can understand the Supermatic IS the overdrive. It´s somehow operated both by the manual choke-like pulllever under the st wheel AND the electric switch in the middle of the dash. That switch goes via the main relay under the hood. If you want to get it out of OD i think the best way is to use the mechanical lever...



Ola

Jon B

My understanding of Super-Matic is that, when it is on, it makes the shifts semi-automatically, when the driver lets up on the gas. The vacuum clutch depresses and the gearshift lever actually moves. (I'm not sure if it shifts this way from 1st to 2nd and from 2nd to 3rd, or just from 2nd to 3rd.) Hudson's 'Drive-Master' did this as well, but it didn't have the addition of overdrive; when you add overdrive to a 'Drive-Master', you end up with 'Super-Matic'.

Geoff

Your overdrive is operating as it should. It does not freewheel when in overdrive, only before the govenor switch activates the relay and the overdrive engages. This enables you to shift gears without the clutch once you get rolling. Once overdrive is engaged, it locks the free-wheel out. You either have to kick it down, or as you relate, slow down until the govenor de-activates the relay. Perhpas your kick-down switch is not working if you can't get back to direct drive by flooring the accelearato pedal.

Geoff.

Fred

While we are on the subject, my 48 commadore 8 won't go into O'D. There is power to the relay but no power to the solinoid or cut out switch on the back of the transmission. If I push on the right contacts in the relay the solinoid clicks. It is a new (relatively) wireing harness from y&Z and worked up until last fall. Any suggestions? I have Hudson wall chart for checking O'D but my electrical education stymies me. Fred

Unknown

Fred



Pull the connections and burnish all... make sure all connections are tight and have electrical continuity... use an ohm meter to check or a powered test light. Also make sure there are no groundings of wires that should otherwise be insulated from ground. Good Luck.

kamzack

Dan;

Geoff is right on target,your OD is doing what it should. My 20 cents worth is, do away with the kickdown and use a off/on switch,so's to control when the govenor engages and disengages the OD. Makes it much easier on 50 year old plus parts and gives freewheel going through traffic, no drag on diff,U-joints and trans gears. I have a small switch located about 3" left of steering column. Also reduces the sudden surge of power that might come at bad time. Thanks for allowing me to participate.

Kim Kramer

Geoff

If the solenoid clicks when you manually close the relay contacts, then the problem is in the govenor, or the control switch at the back of the o/d unit which is activated when you push the bowden cable in. This switch provides a circuit to the govenor, which in turn grounds the relay coil, the other side of which is connected to the A terminal of the regulator. (This is to ensure that the overdrive is only working when the engine is running and the generator charging.)

Geoff.

Uncle Josh

The full Supermatic operation should be thus.

Push the clutch and put the selector in 2nd. Remove foot from clutch. It should not engage.

The clutch should engage when the accelerator is pressed. The car will move easily if it still has the stock 4.56 rear end.

When you lift your foot off the accelerator, the shift lever should move to 3rd

Next time you lift your foot, the OD will lock in, assuming you're over 20 mph.

When you stop, the OD should drop out and the shift lever go back to 2nd, the clutch should disengage and you are ready to go again.

You can drive all day this way without touching the clutch or shift lever, thus simulating an automatic transmission. Ingenious, huh?



By the way. I took mine off, and moved the kickdown switch over below and between the hi-lo beam switch and the clutch. You don't have to floor it to kick it down that way. Chick it's operation before you re-install. It should be Normally Closed. (If it's sluggish, take it apart and clean it, ir get a new one from the Jeepsterman)., and if you position it right you can kick it down with your heel as you push the clutch shifting from 2nd OD to standard 3rd.



On the way home today, I started the 49 in 1st, shifted to 2nd, then 2nd OD, then split shifted to standard 3rd, then 3rd OD, using 5 speeds on a slight upgrade. You can even use all 6 speeds, but why?



On one of my 2 drags ever, I was racing a 51 Fraud with the old 49 Super Six, and gambled on the extra time for 1st OD, and when I went to 2nd standard the hood rose about 2 inches and the Fraud dissappeared behind me.

My 2nd only drag was with my Uncle's 54 Merc auto. My buddy beat me bad with his Dad's 38 Buick as he predicted, and I suspected, since my Dad had a 41.

50C8DAN

OK I now have got the freewheeling thing straight. The kickdown works intermittently so I may have some switch or wiring things to sort out. However, I cannot pull the OD cable while under power in 3rd to get out of OD. Is there something I am missing here? System will come out when slowing down OK.



thanks for everyone's input.

Fred

Dan if you are below govenor grounding speed (free wheeling) you can pull the cable out if you keep engine speed so drive train is fully engaged. If you are in fourth gear you will wipe out internal parts in O'D transmission. Adviseable not to pull out cable while car is moving.

Fred

Geoff

That is normal operation - you can't disengage overdrive once it is engaged, unless you either kick it down to direct drive or slow down below govenor speed.

Geoff.

50C8DAN

Thanks(!!!) everything is working now as it should, at least the OD. Still need to work on the linkage and then the Supermatic.

Unknown

Dan, Geoff's threads are right on, go with what he says.