I finally had the '79 working enough for some road testing and even a trail run. Engine seemed to be running well but possibly down a little on power (it has been a couple years and I've been driving the turbo diesel, so my judgment is skewed).
Due to change in drivetrain, re-adding an H42 with a Toybox, the stock tank was removed and the conferr aux tank is in and being used for a main until the rear axle is moved back and a fuel cell goes in. Just adding that as a possible source of trouble.
On a pre-run/trail test I started having problems with the motor cutting out on steep hill sections. It would start right up after a few seconds and I could continue, but as the day wore on it seemed to be more noticeable and it even began cutting out briefly on the road at inclines.
I did some air/fuel mix adjustments as it was running at pretty high RPM at idle.. 1600 or so. The fast idle screw (?) didn't appear to affect or have enough reach to affect any idle so I turned down the mix. Timing stayed on the mark during adjustment and the engine idled smoothly throughout.
Next weekend was an event/camp weekend, so I hooked up the small trailer and hit the road. I still got some cutting out on highway slight slopes, but as I left the highway for back roads, it began getting much worse over time. Finally stopped and had a small town mechanic take a look. I changed the fuel filter and he said the larger diaphragm on the distributer was timing retard (I had it capped) and by removing the plug, it should run better. So I did that and headed off to see. No change, and more cutting out and backfiring out the exhaust. I had limped to the small town as it was and couldn't get much past 40mph.
Fuel filter did have crud in it, so I am guessing something got into the carb and contributing.
I had turned around for home by then and finally had to call a friend to tow it to his house. By then I could keep it running a couple minutes up to 30mph before it would cut out. I'd have to wait for a few minutes before starting it and limping further.
So now I can get back to the truck to try and fix it, and am hoping to get some advice on where to begin?
edit- things I have considered:
mech fuel pump slowly dying?
float level?
fuel excess from no return line?
Haven't seen extra fuel dripping or leaking through as other threads have described from excess fuel or float bowl overflow.
I am pretty novice at carb troubleshooting, so any help is much appreciated!
Due to change in drivetrain, re-adding an H42 with a Toybox, the stock tank was removed and the conferr aux tank is in and being used for a main until the rear axle is moved back and a fuel cell goes in. Just adding that as a possible source of trouble.
On a pre-run/trail test I started having problems with the motor cutting out on steep hill sections. It would start right up after a few seconds and I could continue, but as the day wore on it seemed to be more noticeable and it even began cutting out briefly on the road at inclines.
I did some air/fuel mix adjustments as it was running at pretty high RPM at idle.. 1600 or so. The fast idle screw (?) didn't appear to affect or have enough reach to affect any idle so I turned down the mix. Timing stayed on the mark during adjustment and the engine idled smoothly throughout.
Next weekend was an event/camp weekend, so I hooked up the small trailer and hit the road. I still got some cutting out on highway slight slopes, but as I left the highway for back roads, it began getting much worse over time. Finally stopped and had a small town mechanic take a look. I changed the fuel filter and he said the larger diaphragm on the distributer was timing retard (I had it capped) and by removing the plug, it should run better. So I did that and headed off to see. No change, and more cutting out and backfiring out the exhaust. I had limped to the small town as it was and couldn't get much past 40mph.
Fuel filter did have crud in it, so I am guessing something got into the carb and contributing.
I had turned around for home by then and finally had to call a friend to tow it to his house. By then I could keep it running a couple minutes up to 30mph before it would cut out. I'd have to wait for a few minutes before starting it and limping further.
So now I can get back to the truck to try and fix it, and am hoping to get some advice on where to begin?
edit- things I have considered:
mech fuel pump slowly dying?
float level?
fuel excess from no return line?
Haven't seen extra fuel dripping or leaking through as other threads have described from excess fuel or float bowl overflow.
I am pretty novice at carb troubleshooting, so any help is much appreciated!
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