I feel like I messed up bad - new to me truck issues after purchase

[IT Cowboy]

I feel like I done messed up A A Ron

I bought a 72 C10 heritage edition today with a 402. The truck is nice, no rust I could see anywhere and it ran and drove great on the test drive. I didn't take it above 40 on the test drive though.

It was running fine on the freeway on the way home and then it started sputtering and surging after about 15 min on the road. It would act like it wasnt getting enough fuel and surge in rpms and power. If I put it in neutral going down the road and revved it is would rev ok. If I stopped and left it running for 5-10 minutes and then continued it would run ok again for the first 5 minutes or so and the start surging and sputtering again. If I was idling it didn't surge and if I shut it off it would start up right away no problem then idle fine. There is a mountain pass on the way home so I pulled over and found a mechanic shop close by and left it there for them to look at. I might need to have it towed to a classic car mechanic to have it diagnosed

It was not too warm outside today and the heat gauge stayed about 1/2 while moving. I am disappointed with myself and feel like a kid with a new broke toy. I keep telling myself it probably isnt anything to serious or expensive.



Small Update:

It made it to the shop I picked that is supposed to have a team of 5 techs that build and service rods and older vehicles. The first shop where I had to leave it was really nice but they are a modern shop and no-one really knows much about carbs. They didn't charge me anything for keeping it there two nights so I sent them a large box of donuts.

I sent an email to the "new" shop explaining the issue in detail and listed what several people told me it might be. I feel like I am waiting for a biopsy test to return but I think Jesus was looking out for me that day and put me in a place to keep the truck and myself safe. The trip to the shop is going to cost me dearly but it will be worth it if it is fixed right and I don't get hit on a mountain pass. More to follow


Second Update 02/06/2025

The shop I have it at called and said the fuel filter by the car was clogged nearly solid. I asked him to leave it out and put one inline instead.

Final update 2/8/25

I drove the truck home today going 168 miles up the mountain pass and bypassing phoenix and construction. It ran great and was a good trip and I think I averaged about 12 miles per gallon which I didnt think wasn't to bad considering the climb and elevation and it is a 402. The outdoor temp was around 55 and the truck temp gauge went to just a hair over 1/2 a couple times. Most of the time the temp was just below 1/2 and even at the 1/4 mark.

The truck fits in the garage with about a foot left on each end.

Arrrg, it has a leak lol. When I made it home the truck sat in the drive for about and hour and there was one small drop underneath less than the size of a dime. It looks like it came from the weep hole in the bottom of the flywheel shroud. I let the truck sit for another 2 hours and there were no more new drops. The bottom of the trans had oil on it but it didnt look like it is from the trans, I am guessing it is the rear main. If that is all it leaks I am good with it and trying to fix it might make it worse.

Thanks everyone for all the help and support.