M37 hydraulic clutch?

[jeffhuey1n]

I can't seem to find anything on the subject so here it goes: the clutch pedal when depressed, actuates a hydraulic cylinder, similar to the brake master cylinder. It is in fact mounted just outboard of the brake master cylinder. A hose runs from the back of the "clutch cylinder" to a smaller actuator on the opposite side of the truck which is attached to the shifting forks(?). It may very well be that I just need to add fluid of some type to get it working.

Is there normally a hydraulic clutch setup in a M37?
And, any recommendations on what type fluid to use?

Next is to figure out how to service the cylinder.

I'll post pics in a few minutes, just wanted to get the questions out there ASAP.

Pictures below. There is a filler plug on top of the "clutch cylinder" which is pretty much inaccessible. There is a valve that a line could be attached to to service it, maybe... The mechanical linkage is not connected to anything.

 

[Roller]

M37 didn't have a hydraulic clutch, strictly mechanical. Dot 3 is what you use in your setup.

Frank

 

[jeffhuey1n]

I figured it out. Because this truck has a 318 V8 made between 1957 and 1966, the mechanical linkage will not fit. The previous owners solution was to install a hydraulic clutch. He used a M37 master cylinder, about 3 feet of aircraft grade hydraulic hose, some fittings and a second hydraulic cylinder which looks like a Warner part. I had some extra Dot 5 so I filled the cylinder and with my son pumping the clutch pedal, I bled the secondary cylinder until no more air came out of the fitting. Clutch operates correctly now. I'll have to pull the whole system eventually to fix the inevitable leaks. This truck has more helicopter Crew Chief adaptions, improvisations and overcame all obstacles that got in the way than anything I've ever come across.