Help all dodge guys!!! Gyromatic troubles

hello, i have been having problems with the gyromatic transmission in the 1950 dodge coronet that i just bought. when i bought it i knew it had some problems. at first, when it would try to shift from 3rd to 4th, or 1st to 2nd, it would constantly grind unless i threw out the clutch, then it would shift. when i drive, i start in high gear, and i let up at 13-15 mph...but it grinds! i decided to change the fluid in the ****** and did with 10w motor oil....and i put 3 pints in. i had read that you have to have the correct idle to have it shift, but it has a chrysler spitfire flathead in it, and i dont know how to test the rmp. now that i changed the oil, it grinds for maybe 1-2 seconds, and then shifts. any thoughts or suggestions would be appreciated. thanks-matt

 

There is a one way clutch in the trans, like a coaster hub on a bicycle. It could be jammed up. Or your RPM idle too high. Cut it down to 450 or so. Those motors idle VERY slow, first check the ignition timing is to specs (not advanced too far) then cut down the idle speed as far as possible, adjust the idle mixture if necessary, cut the idle speed again, go as slow as you can without stalling, it should be going about half the speed of a modern engine.

 

How do I adjust the ignition timing, or check it for that matter...also, I know how to adjust idle but not mixture...how do I check the r.p.m? should I do this when it is in gear or neutral?

 

10 wt oil may be too heavy. I have auto trans fluid in mine. It works fine but it holds a lot more than 3 pints. Closer to 2gallons.

 

10W motor oil is correct for the trans. There is an adjusting screw on the throttle linkage for idle speed and another on the base of the carb for mixture. Warm up engine, put in neutral, back off the idle speed until it is slow as possible. Turn the mixture screw in until the engine hesitates and back it out 1/2 to 3/4 turn until it smooths out. See if you can slow down the idle some more.

Also check the spark advance (timing) and set it to factory spec.

The engine should idle down to about half the speed of a late model engine and just sit there purring like a big cat.

 

There may be other things wrong besides carb adjustment. The carb is actually the last thing you adjust in a tuneup. The rule is, adjust valves then do ignition then set the carb up last.

You may want to do a compression test and tuneup to make sure it is running right. The carb adjustment is in case someone has been monkeying with it and didn't know what they were doing.

 

got the idle down but it still seems to be grinding for a second before shifting...do you think changing the fluid again would help? where can i find the specs for the timing for the spitfire 6 in it???

 

You need a repair manual, they turn up on Ebay or at auto flea markets.

 

Ordered a manual for the gyro-matic... hopefully it is here by next week. I will keep my eyes open at the next swap meet that is here locally

 

My reply was for the fluid in the fluid drive coupling.

 

You probably need to clean the electrical contacts on the governor (decides when speed is sufficient to shift) and the solenoid, allows the shift to occur.

These are really simple and usually bullet proof trasmissions, and not real fussy when everythig is correct.

take a look here until you manual comes.

http://www.imperialclub.com/Repair/Transmission/index.htm

should tell you what you need to know about trouble shooting and repairing.

Everything here from the late 40's will apply to your Gyromatic. Sames trans different name. Official nomenclature was M 6 semi automatic. The fluid drive was used in front of a couple different transmissions.

Idle rpm should be 450 to 500. Also there is a bunch of wires on the support fo the air cleaner that effect the transmission. The is one that grounds the coil during the shift. This is to allow for some slack in the drive line to ***ist the up shift. so check and clean all those connections too.