I;'d say fuel issue. Check/replace the filters first, but my vote is:
I had this issue last year about this time. Ran GREAT, then when it warmed up fully it would start stuttering like I was running out of gas and die. If I let it sit for 15 minutes and cool down, I could drive it home. It would only happen warmed up, and when I stepped on accelerator. Idled fine. Made me crazy looking all over for the solution.
I point the finger at the vacuum accelerator pump in my carburetor. Had the carb completely re-built, installed it, and haven't had a problem since.
-T
idles fine - no power under load
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Re: idles fine - no power under load
I like to try the cheap and easy things first.
Bad fuel, rusted lines, bad filters, crud in the carb.
You could test fuel pressure if you have a gauge, if not, jerry-rig an external fuel source to the carb
and see if the truck runs better. If so, that would tell you it's a fuel delivery problem, If not running
any better.... might be electrical.
Cheap and easy is my motto
Jerry
Bad fuel, rusted lines, bad filters, crud in the carb.
You could test fuel pressure if you have a gauge, if not, jerry-rig an external fuel source to the carb
and see if the truck runs better. If so, that would tell you it's a fuel delivery problem, If not running
any better.... might be electrical.
Cheap and easy is my motto
Jerry
Member: Arizona Military Vehicle Collector's Club, Treasurer.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Past Pres
Member: MVPA #26600
Member: NRA
‘43 GPW, '53 M37 W/W, ‘54 M170 Field Ambulance,
59 M43, '76 M151A2, '86 CUCV,
'43 GPW, 416 & 101 trailers.
Re: idles fine - no power under load
started the long road to finding my issues with the idling/power.. thought I would begin with the fuel system.. as I wrote earlier, I wanted to see exactly what the condition of the fuel tank was anyway. so thought I would start there.
BTW.. I have the original tank in place, and I DID NOT bust or break one screw getting the access plate off the tank. or the fule sender unit for that matter
After removing the access cover in the bed, the fuel filter access plate and disconecting all lines, I was able to look inside the tank.
holy cow.. what a mess in there. wow.. I was able to reach in the tank and scoop out handlfulls of rusty sediment. the fuel filter was a clogged mess. how on earth this thing allowed fuel past it to run the engine in the first place defies logic.
well, I proceeeded to drop the tank, as a good cleaning and re-lining of the inside is in order..
its now outside of the workshop awaiting my next trip in a few weeks to begin cleaning and re-lining the tank.
I have had great luck in the past using a local supplier of a product called Retro restorations. I get a break for shipping as he is nearby too, so I use him for gas tank relining product.
www.retrorestoration.net
he carries the complete kit, to clean and re-line... so far. all three tanks I have done in the past held up well..
anyway, thats my next cabin visit job to tackle.. one bite at a time I guess.
I ordered the in line stainless steel fuel filter from Midwest military as well as a carb rebuilt kit, so those are next after the fuel tank reline job..
I am sure eventually the fuel lines will need attention... they MUST be as rusty I would imagine inside if the tank is so bad? maybe Ill order the replacement pre-bent lines and do the job now as the tank is out.. gotta think about it
anyway, thats my progress report
BTW.. I have the original tank in place, and I DID NOT bust or break one screw getting the access plate off the tank. or the fule sender unit for that matter

After removing the access cover in the bed, the fuel filter access plate and disconecting all lines, I was able to look inside the tank.
holy cow.. what a mess in there. wow.. I was able to reach in the tank and scoop out handlfulls of rusty sediment. the fuel filter was a clogged mess. how on earth this thing allowed fuel past it to run the engine in the first place defies logic.
well, I proceeeded to drop the tank, as a good cleaning and re-lining of the inside is in order..
its now outside of the workshop awaiting my next trip in a few weeks to begin cleaning and re-lining the tank.
I have had great luck in the past using a local supplier of a product called Retro restorations. I get a break for shipping as he is nearby too, so I use him for gas tank relining product.
www.retrorestoration.net
he carries the complete kit, to clean and re-line... so far. all three tanks I have done in the past held up well..
anyway, thats my next cabin visit job to tackle.. one bite at a time I guess.
I ordered the in line stainless steel fuel filter from Midwest military as well as a carb rebuilt kit, so those are next after the fuel tank reline job..
I am sure eventually the fuel lines will need attention... they MUST be as rusty I would imagine inside if the tank is so bad? maybe Ill order the replacement pre-bent lines and do the job now as the tank is out.. gotta think about it
anyway, thats my progress report
