CCKW open cab on G-506

[bobc]

I couldn't do this project if I didn't have all the left over parts from three parts trucks, I did the same thing when I restored my half-track, at one time I had three of them down here, what parts I didn't need were sold to finance the one I kept, of course it helps to have 5 acres and a understanding wife and mother in law, and no annoying neighbors!

[bobc]

Finally got all the brakes rebuilt! The wind came up and since I'm working outside I lost most of a day, that darn sand was blowing around the back of the barn and wanted to blind me, but things calmed down today and I was able to clean all the parts up and rebuild the wheel cylinder, picked out the best oil free set of shoes from the pile, they actually look almost new, just had time before dinner to get a coat of primer shot, finally after watching the end of American Graffiti, I went back out and shot a couple coats of color, now with any luck tomorrow will be nice and I can bleed the system again and see what kind of pedal I get, I'm going to hold off on rebuilding the master cylinder till I see if I can stop this beast without the booster!

[bobc]

Minor set back on progress today, I got all the brakes done and replace the rear flexible hose, bled the whole system then fired it up to take a run around and see if I could get enough brakes to stop it without the booster, I pulled it out onto the dirt road and shifted into high range and 2nd gear and the truck wouldn't hardly move, so I stopped and put it back in low range 2nd and it moved again but only till it got rolling, when ever I tried to shift into a higher gear the clutch would slip, I've only ever driven this around the property and off and on the truck when I got it so I didn't know what condition the clutch was in, I now know it's shot! But I was able to determine the brakes work really well, I was able to lock up the rears on the dirt road, so I should have enough to stop it on pavement. Now I have to find a clutch, I spent this evening walking around the property checking stock, I only have one parts 270, some one pulled the head off a long time ago, but the bell housing is still on it so if the clutch was any good it should still be useable, only problem is the stupid way GM bolted the bell housing on, what the heck were they thinking, surely not about us poor guys way down the road, so I have to drop the bottom end out of this engine so I can check the clutch disc!

[bobc]

I got lucky on the clutch in the stuck engine, it was practically new, you can still see the cross hatch marks on the pressure plate, I had my local NAPA order me a pilot bearing, I picked up a couple alignment tools from a friend, which were too big because not many trucks used a pilot bearing, but I had the blown up chevy transmission sitting in the bone yard so I pulled the input shaft out of it, cleaned it up well in it should work fine, so since I had every thing set up I pulled the tranny on the open cab, I pulled my yard truck up to it and used a cable hand winch to slide it out, then I rolled the truck forward and it came right out, I had my wife turn the engine over with the hand crank while I unbolted the pressure plate, of course I forgot to take the throw out bearing arm off, on most vehicle this isn't required, but since this isn't a normal truck you do, what a pain, the clutch plate was shot, the pressure plate has cracks and the spring fingers are flat! I've cleaned up the pressure plate and clutch plate, if I get a little time tomorrow I'll run the sander over the flywheel, I don't have time or money to do it properly but as much driving as I expect to do this should last me the rest of my life, I'm hoping to run this truck up to a car show next weekend, I won't have the bed on or the seats done but I should be able to get the front end done, we'll see!

[bobc]

Things didn't go so well with the clutch installation, after getting the transmission all bolted back up and getting the clutch pedal back on and hooked up I couldn't get the clutch to disengage , no matter how far I push the pedal the clutch won't slip enough to turn the trans over when the pedal is down, I had a big family thing that I had to take some time off the project,I promised my nephew I would get my 43 White M-2-A-1 half-track running so I could take him for a ride, so I haven't had time to get back onto the open cab and see what I could figure out on the clutch, at this point if I had a good V-8 with an automatic transmission handy I would stuff it in there, I have actually took a look at a 460 with a C-6,I'm just getting so frustrated fighting this original engine trans set up, and there are so many stupid things they did that just about drive me over the edge ever time I have to deal with them, maybe next week after things settle down I can get back out and figure out what went wrong with the clutch!

[Sleeve]

Sorry to hear that, clutch and transmission work always stresses me out . The thought of having to start over never thrills me because it is such a PIA to get the tranny back in!

Couple of thoughts..... my clutch had stuck to the pressure plate and fly wheel after it sat for a few weeks even though it was free when I first installed it. I broke it loose with a bar on the output shaft u joint yoke and it has been fine ever since. Might be worth a try. The other thing that comes to mind is the throw out bearing, the original was pretty tall and there is a shorter version that if swapped in by mistake would give that problem. There are two pivot ball lengths for the TBO arm too and the short one of those can give you grief. It sounds like your'e a better mechanic than me but sometimes in the heat of things we forget so maybe this will be of some help.

-Mike-

[Sgt. Hancock]

Bob,did you remember to install the "J" hook that links the clutch pedal to the throwout fork, or did you attach the pedal directly to the fork? If you forgot to install the adjusting link you will have difficulty disengaging the clutch.

[bobc]

I did install the J hook, I cranked it all the way down to try to get the clutch to disengage and still couldn't get anything! The throw out bearing and pivot ball were all from the engine tranny set that I'm using, the only thing I changed was the clutch disc and pressure plate! But from what I have read you are supposed to set the three pieces up as a set, I think this is where my problem is!

[Sgt. Hancock]

Your problem may lie in having the 'short' throwout bearing, which is for the original clutch assy. If you used a modern diaphragm clutch it will be necessary to use the 'tall' throwout bearing. The difference in height is just about the maximum adjustment on the 'J' hook, or 1 inch.

[bobc]

Well after a rough summer I'm finally getting back out into the yard, I spent most of the day trying to get the weeds down around the truck, some were 4 foot tall with a stalk 1 inch thick, but the horses and goats eat them so once I get them knocked down they don't go to waste, if the horses and goats didn't eat all the trees and bushes I would let them clean them up! When I last touched the truck I was trying to get the clutch working, Sgt.Hancock thinks I may have used the short throw out bearing, which sounds exactly like what's happening. Does anyone have a number for the longer throw out bearing, my parts guy could probably dig through his books and find it once I have the short bearing out, but it would sure be nice to have a number to start with. Thanks Bob.

[bobc]

Last spring I made a deal with a friend to swap the cab from the donor chevy for some open cab CCKW parts that I've been needing to get for this project, a top bow with both of the "nuts" that hold it up, another leg for the gun ring, but best of all is a wooden steering wheel, I think it's actually the Canadian type, but it's NOS and will look much better then the plastic ones I have to pick from, just a couple more catch up projects around the place and I should be able to get back to the truck!

[bobc]

Well after building a quanset hut for a hay barn for my mother in law, building some trailer skirting for my dad, cutting down some old dead elm trees for fire wood,I finally got back out to the open cab today, it's hard to believe how easy it is to remove the tranny, since I didn't have all the bolt on stuff put back from last time, so I set up the truck and the yard truck and slipped the tranny back out, I got out my micrometer and took all the measurements, I thought I had the clutch package from the 58 1 1/2 ton truck that I sold the engine out of this summer,I was hoping it might have the proper tall bearing, as I was looking around for it I found the engine and tranny from a 1950 Chevy sedan I sold this summer, the guy was going to hot rod it so he didn't want the stovebolt, the dust pan was off and I looked at the bearing, it looked very much like the one from the CCKW,and being out on the ground and the tranny only weighing about 20 pounds I popped it off, the bearing is almost identical, it's about a 1/2 taller, so I took all this stuff and info up to my parts guy, he's an old school parts guy that can still pull out a book and find just about any thing, so we found a bearing that is about one inch taller then the original one, I looked at that one on ebay that sgt.hancock talked about but it's 3 inches tall and from what I could measure while the tranny was still bolted up I think that will be too much, so we'll see what my parts guy gets in tomorrow, if it actually works I will be sure to list the number.

[bobc]

VICTORY!!!!! I finally got the tranny slid back in, it actually went in much easier this time, my wonderful wife came out and rolled the truck backwards with a 4 foot bar in the wheel, then using a tie down strap I was able to align every thing and it slipped right in first try, probably helped that the clutch was lined up from last time, then I bolted the pedals on put it in gear and pushed the pedal down and the tranny output shaft turned over perfectly, now if I can move in the morning I'll try to get the rest of the parts installed so I can drive it!

[bobc]

Just in case some one else has this problem the bearing that I ended up using was from parts plus and it's # P614037 .

[forestry4evr]

Bob,

You almost have her running under it's own power. That is a memorable event. Just try to drive it around the yard the first time without a smile on your face!

From my memory this combination is the GMC 270 mated to a Chevy bellhousing/flywheel/pressure plate/clutch to a Chevy four speed right? Or is it all GMC engine to transmission with a Chevy transfer case and rear?

Paul