Help a newbie with an M6 situation

[greg g]

I just made aquaitance with a fellow with a 53 or 4 Desoto with the semi Auto.

He is having trouble with the trans. Says he has to rev the engine then bump the clutch to get the car to move even in low range. He has checked out the trouble shooting deal on the Imperial club website but still has not found the problem. Wonder if its clutch related rather tha FD or trans problem?

Not real familiar withthe M6 so looking for some input to help him out before he puts a chey drive train in it.

[adam_knox]

Hmm, if he went through the trouble shooting guide I don't have much advice. The idle setting is important as well as the fluid levels. Have him check the fluid drive levels and the transmission fluid (its two different components). Also, have him check that his accelerator pedal isn't stuck. The car won't shift, or is force shift if the accelerator is engaged when it hits 15 mph.

Tell him good luck for me!

[PatS....]

The M6 has a regular clutch bolted to the Fluid Coupling that wears just like a regular clutch and needs very occasional adjusting to compensate for wear just like a regular clutch...the adjustment might be worth a try.

Then check that the ebrake is not binding. (That would also make hydraulic shifting difficult)

[Kevinb71]

How about the brakes. Are they dragging or locked up? Can he push it by hand in nuetral?

[moose]

If he finds out that something is wrong with the trans, I've got a spare. Mine's working fine right now.

[hillbilly4008]

Hi everyone. I'm the newbie with the problem. Now what I have going on is when I take my foot off the safety clutch after shifting into gear the car stalls. The only way to move the car is to drive it like it has a manual transmission. From what i've researched I'm told that the car should be able to sit at idle while in gear and not stall, unfortunatly that isn't the case with my car.

Any advice? Greg suggested checking a vacuum line, but I only have the one going from the carb to the dizzy, and that appears to be good.

[PatS....]

That almost seems like an impossibility if it actually has a Fluid Coupling. Have you ever been able to let the clutch out without it stalling?

I wonder if, like Fred's car, the Fluid Coupling has been replaced with a regular flywheel over the years.

Can you get it up on a hoist or somehow take pictures of the bellhousing and transmission?

When you say drive it like a manual transmission, does that mean that towards you and down is first gear?

[Big_John]

Hey Joe!

Assuming stuff like the fluid drive is full of the correct fluid, I'm wondering if there is a problem with the fluid drive itself. I looked at my service manual and they make reference to a bearing failing in the fluid drive. I would think that the drive could freeze up if that bearing failed.

[hillbilly4008]

Pat, I've only drivin this car around my driveway so far. I have yet to find out if it even shifts going down the road. Yes, this stalling issue has been a factor since day one.

Looking at the car from underneath it definatly does have the M6 transmission still intact, and all the solenoids intact and wired.

I will try and pull the fill plug access plate tommorrow and see whats up. Hopefully get it on the lift and shoot some pictures.

Edited May 9, 2011 by hillbilly4008

[hillbilly4008]

I know my carb is out of adjustment, so fingers crossed on that one. I'm having a friend come tweak the carb tuesday. Which part of the carb did you have to adjust to fix the problem?

The car doesn't jump then stall like a typical manual transmission does when you just let off the clutch, It creeps a little bit then it stalls.

[Al B. Bach]

This may be simple but I know that is the idle is set too low then mine will stall when you let the clutch out. How's your idle?

[Dodgeb4ya]

If you were to take all the trans wiring off the transmission and drive the car, You will find that it will upshift into high range the second you let off the gas-even at 2 MPH!. It will stay in the high range at all times-no downshift is possible-unless you come to a complete stop and hold the clutch pedal down and wait for up to 5 seconds for oil pressure to drop to let the direct speed sleeve pull rearward and off the input shaft. You need the electronic controls to provide a downshift when you want it ( throttle KD) or a governer controlled downshift as in coming to a stop.

The car should still move normally in and around your drive way even with a high idle. The trans doesnt even need to be full of fluid to be able to drive around the yard /driveway ect in low range.

The brakes need to be checked-both E-brake and service brakes. The Fluid coupling possibly could have a weird problem-low on fluid locked up ect. The clutch itself possibly and lastly an internal issue in the trans-free wheeling section or input shaft?

Jack it up pull the driveline and test the trans for smooth normal rotation and go from there. Never had an M-6 with this bump the clutch to get it to move issue. Is it a optional torque converter coupling as in "Fluid Torque Drive" as used in the Chryslers with a actual torque converter-now those do have some serious issues! I know DeSoto's had their own version of it. Pics of the underside of trans/coupling housing would be good too.

Bob

[greg g]

Here is some stuff on the fluid torque drive system that started to be used in 51.

Navigate the booklet withthe page bar at the top as the next page lik near the bottom isn't always reliable.

[hillbilly4008]

I just pulled the fill plug access panel and inspected the coupling, its very clean. I also pulled the fill plug and the fluid level is right where it needs to be. It looks that none of this has been done since it left the factory.

As soon as i get another car off the lift i'll put this car up in the air and get some pics for everyone.

Edit: Greg, I'm not seeing any links in your last post.

[greg g]

http://www.imperialclub.com/Repair/Lit/Master/049/index.htm

[hillbilly4008]

Good stuff right there. I'd bet the oil was never changed in that converter, that manual says do it every 20k miles. My odometer reads in the 90k miles.

[hillbilly4008]

Right now I am thinking all of my problems are carb related. Could someone please point me down the path of getting my carb back to its stock settings. My father and I have been just tuning it by ear until this point, so besides my float still being too high, I am sure every thing else is out of whack also.

I think I've found that the main idle screw should be set at 1.5 turns. I can't seem to find any more info. The carb is a Carter Ball & Ball, setting ontop a Canadian 251 L-head, with the head shaved .050, and split exhaust manifold.

[greg g]

Check out the heading IF motor STALLS. Did you read through the section under special adjustments? It looks like there is an adjustment on one of the screws that connects one of the wires and a start up setting for it. did you check the operation of the spring and plunger in the assembly?

[greg g]

or this type

[hillbilly4008]

Well I think we have the problem licked. Yesterday I found that I had absolutly no compression in two cylinders. So the head, and manifolds came back off. The exhaust valves were stuck wide open on the two cylinders. After a few hours of soaking and some "gentle" persuasion they freed up. While I had the engine turning over to check the valves I noticed that the fuel pump seemed to have ALOT of pressure.

I put it all back together today and installed a fuel pressure regulator set at 3lbs. Now the engine runs great, the carb no longer leaks, AND the stalling issue with the M6 has been resolved.

[greg g]

did you get it down the road to see if the upshift is working??

[hillbilly4008]

Not yet, my seats are out because I am repairing the floors.