Picked up a 1970 GMC C3500 dump truck that needs some TLC
- Thread starter pclausen
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pclausen
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Thanks buck. Yes, I really did this truck. Did a little work on it over the holidays. Front shoes didn't look all that hot:
So I picked up a new set from Napa for $18 bucks. Gotta love the cost of parts for these older GM trucks! Since I had the front hubs off, it was a good time to repack the bearings with were otherwise in excellent shape!
Front axles all done and ready for re-assembly:
I also took care of the relay for the HEI coil via the relay mod mentioned earlier. I had some 10ga wire laying around that I ran to both the battery positive and negative terminals. I'm quite certain I have a full 12V at the coil now.
I took the carb off to figure out what was up with there only being 2 bolts holding it on. Turns out the intake was never drilled and tapped for 4 bolts!
So I just put it all back together for the time being. This last week or so, with the weather being quite cold in these parts, I really have to pump the gas pedal to get it started, and then for the first minute or two, it stall if I give it any gas, and there is no power at all at low rpms. So I have to let it idle for a while, and then really rev it up to 2-3k to get it going in granny 1st, and keep it at those rpms for another few minutes before I can shift into 2nd without stalling. Once the engine is fully warmed up, everything is fine. Maybe something with the electric choke or something?
So I picked up a new set from Napa for $18 bucks. Gotta love the cost of parts for these older GM trucks! Since I had the front hubs off, it was a good time to repack the bearings with were otherwise in excellent shape!
Front axles all done and ready for re-assembly:
I also took care of the relay for the HEI coil via the relay mod mentioned earlier. I had some 10ga wire laying around that I ran to both the battery positive and negative terminals. I'm quite certain I have a full 12V at the coil now.
I took the carb off to figure out what was up with there only being 2 bolts holding it on. Turns out the intake was never drilled and tapped for 4 bolts!
So I just put it all back together for the time being. This last week or so, with the weather being quite cold in these parts, I really have to pump the gas pedal to get it started, and then for the first minute or two, it stall if I give it any gas, and there is no power at all at low rpms. So I have to let it idle for a while, and then really rev it up to 2-3k to get it going in granny 1st, and keep it at those rpms for another few minutes before I can shift into 2nd without stalling. Once the engine is fully warmed up, everything is fine. Maybe something with the electric choke or something?
BIG DOOLEY
Platinum Member
Nice work truck!:thumbsup:
Looks pretty solid for the age.
Looks pretty solid for the age.
bdeboer
Platinum Member
It sounds like the choke is not doing anything at all. Manual choke kit is one option.
dodge man
Super Star Member
I was thinking the same thing, a manual choke is the way to go and fairly cheap. They used to make kits for that kind of thing.
OP
pclausen
Veteran Member
Thanks. I'll look into a manual choke kit. It does have the electrical choke on the carb, but it clearly is not working. Will look into it and depending on what the issue is, the manual choke kit might be the way to go. It already have a place for it in the dash. Will be a lot cheaper and less work that replacing my clutch from all the high reving and slow clutch releasing I'm forced to do right now until the engine is fully warmed up!
Looking4new
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Seeing as you are missing the other two holes for the carb, there is your excuse to get a 4bbl battleship and a 'Q' jet. While you got the battleship off, you might as well get a set of 202 heads for it. They along with the 4bbl will wake up that old 305. IF you do that, then a set of headers with dual straight pipes (if straight pipes are not an option, then cherry bombs will make you barely legal) and off you go.
It all depends on how much you want to spend on a 42 year old truck.
While you got the battleship off, you might as well get a set of 202 heads for it. They along with the 4bbl will wake up that old 305. IF you do that, then a set of headers with dual straight pipes (if straight pipes are not an option, then cherry bombs will make you barely legal) and off you go.It all depends on how much you want to spend on a 42 year old truck.
timswi
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Seeing as you are missing the other two holes for the carb, there is your excuse to get a 4bbl battleship and a 'Q' jet.
It all depends on how much you want to spend on a 42 year old truck.
I agree, a 4bbl on a 305 makes a huge difference in my experience...Never liked the 2bbls's got lousy gas mileage and never had any kick.
pipes and glasspacks are a good idea too....None of this is too expensive.
Verticaltrx
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Definitely go back to a manual choke. I'd bet the truck was originally setup with one and it was lost when they swapped in the current motor.
As for the carb and intake, I'd have mixed feelings about swapping it. Our '75 C60 (with a 350) has a 2 barrel truck carb and it runs great. Plenty of power for what it is. With that said, the quadrajet is a heck of a good carb and I'm running one on my '79 F-150 for it's good off-road attributes. A lot of people hate quadrajets, but once you figure out how to work on them they are pretty straight forward.
As for the carb and intake, I'd have mixed feelings about swapping it. Our '75 C60 (with a 350) has a 2 barrel truck carb and it runs great. Plenty of power for what it is. With that said, the quadrajet is a heck of a good carb and I'm running one on my '79 F-150 for it's good off-road attributes. A lot of people hate quadrajets, but once you figure out how to work on them they are pretty straight forward.
OP
pclausen
Veteran Member
I picked up a manual choke kit for 10 bucks as the auto parts store. Was a snap to install and wow, what a difference to have a working choke!
I pulled the plugs and they are pretty fouled again after only about 75 miles, which was one trip to the dump and then just hauling chips around on my land.
I found this on a local craigslist ad:
It has the performer RPM intake which is not really ideal for me, but I can probably sell it and the brand new Mallory distributor, towards a more suited intake and carb. The block is a 020 casting 350 and the heads are 062 vortec heads with roller rockers. Also has high rise valve covers. Cam is supposedly mild. It is a 355, which I guess is the 350 bored 030 over. He had it listed for $800 obo or gun trade. I have offered him a few hundred bucks and a shotgun. Let's see if that works for him. He bought it as it sits for a project he is no longer doing, so it has to go. If I do get it, I'll do headers, pipes and glasspacks.
I pulled the plugs and they are pretty fouled again after only about 75 miles, which was one trip to the dump and then just hauling chips around on my land.
I found this on a local craigslist ad:
It has the performer RPM intake which is not really ideal for me, but I can probably sell it and the brand new Mallory distributor, towards a more suited intake and carb. The block is a 020 casting 350 and the heads are 062 vortec heads with roller rockers. Also has high rise valve covers. Cam is supposedly mild. It is a 355, which I guess is the 350 bored 030 over. He had it listed for $800 obo or gun trade. I have offered him a few hundred bucks and a shotgun. Let's see if that works for him. He bought it as it sits for a project he is no longer doing, so it has to go. If I do get it, I'll do headers, pipes and glasspacks.
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