the carb butterflies are fully open by default on Holley-equipped R6602's .. I see you have the holley.. A better-starting, slightly better on fuel replacement is a Zenith that superceded the holley, it should show up in later Dash-20's .. On your holley truck you should be able to manipulate the throttle linkage between the pedal and the governor, but I believe the butterflies cannot be manipulated until vacuum is applied as you suspect
You are correct about the carb. The linkage was frozen and things weren't right in things attached to the linkage. The accelerator pump was also stuck. I was able to lube things up and get the linkage working but the operation was a bit wanky, it would stick when depressing the pedal sometimes, stick 1/2 way when released, sometimes and just wasn't right. I found that the plate on the part of the linkage going up the firewall directly off of the pedal that has the return spring and hand throttle cable attached to it was flopping around loose on the rod and was acting as a stop. It had been that way forever from the looks of it, so I just ran the jamb nut that holds the plate against the end joint back into the position it should have been in....tight against the plate and end joint...and everything fixed itself. I had to PB the accelerator pump shaft and work it a bit and that freed up nicely. The pedal, linkage and throttle lever all worked smooth.
First, a big shout out to
@BLK HMMWV, he was a great help....even stayed off his phone! It would have been much more difficult to get what was done without him.
Did a fluid check, everything looked good.
We threw some nice hot AGM batteries in it and powered things up. No Genie smoke, guess that was a good thing! I was totally expecting to have issues with the starter and/or the linkage but NOPE! Stepped on the plunger, the thing cranked like it was new! Hooked up a pony tank, removed the fuel inlet at the carb and gave it a crank....or four, no fuel delivery. Put the can on the fender, gave the feed hose a suck....new gas don't taste as bad as the gas did when I was younger.... Let gravity take over and re checked supply to the carb, good supply now! BUT! Gave things a crank with the choke on, took a bit then a big POP, it lit off and idled, on 3 or 4 cylinders, smoking black like a diesel. The choke didn't return all the way.
Fixed that issue, fired again and gave it a bit of RPM to try and clean things out.....90 psi oil pressure at this point....here comes the above BUT! Giant fuel leak out the bottom, right out of the FP vent. Shut it down, looked things over, no other leaks, one fan belt started to come apart, didn't look to see if it started to build air, didn't try to move it, DID try the steering and it is nice and easy when the engine is running.
Ended up removing the fuel supply, firing and running it until it was out of fuel, pulled the batteries, got belt numbers, pulled the FP to get numbers. Also found the reason for the big POP just before it fired. I forgot, we went around to every vehicle in the collection and put trailer aluminum tape over the exhaust pipe outlet. Blew that stuff of like a bomb!
Found belt cross overs in the 5T parts section
Then and Now doesn't answer their phones except for Mondays and Thursdays, called them with the numbers today, they have a kit for the FP and it is on it's way.
As for the carburetor, I did find out that the Holley is, well a Holley, I hate them, and there is indeed an "upgrade" Zenith, 63AW16. I searched here and found the zenith number, also found a used one on E-bay. Also found out that Evil Dr. Porkchop might have some parts, PMd him, turns out the carb on E-bay is his. He also did some peeking around and says there might be a couple more in the inventory.
The Museum has been using a place in NY for Zenith carb parts and kits. I did call them last night with the Zenith carb number, but have not heard back. They might have a Holley kit, but, since the wrecker is going to be a worker bee, I think the Zenith is a good choice. Rumor has it that there is a rebuilt crab laying around, so that means gaskets only to renew it. I know Treadwell can make the gaskets we need, just need to wait for word back on the Zenith carburetor.
@msgjd, Yeah, I think I will take you up on the Ermeto to normal/SAE fittings list. I see a minimum of 6 of the lines on the crane upper, they look to be #20 or so and 4 or 6 under the rotator area that look like 12 or 16. One end looks to be just NPT but the other is funky, where it joins a hard line. Looks like almost a compression fitting.
Sorry, no pictures or videos. I will say that this thing pushes some air out the exhaust pipe!
I am sure there is going to be more on this to follow. I know it will need brakes....the pedal is stuck and I am sure the MC and wheel cylinders are in need of attention. The PB does work though!
The last time this ran was 1993. It was used in an episode of Combat Garage. It was used to remove the GAA engine from the E8 Sherman to R&I the clutch.....30 years!