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

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.

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

What is exactly did the seller say a heritage edition was? I don’t think that’s a real thing. As for the way it’s running I’d check for vacuum leaks and look over the fuel system first.

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

I'm guessing it's the fuel sock. It's on the end of the pickup tube, and after so many years it's rotten. It gets sucked in while you're running down the road. When you stop or reduce the demand it lets fuel flow.

It's actually a pretty common problem on older vehicles. The fix is to remove the sending unit, pull off all remnants of the sock, and replace the fuel filter.

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

Is the sock on the end of the sending unit and do I just remove it from there and not replace it and just replace the one on the carb inlet.

Could I just replace it with an inline filter somewhere?

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

If it is indeed the strainer on the sending unit, you just pull what’s left of the old one off and press the new one on. Definitely change the filter in the quadrajet inlet if present and any other filters that might have been added in the last 50+ years. Also a really good time to replace the sending unit gasket on the tank and rubber fuel lines inside the cab that attach the metal lines to the sending unit. Here is an example of the Strainer.
https://classicparts.com/1967-87-gas...ock-filter-3-8

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

More fuel demand causing the fuel filter issue? When I started down the road again it would be ok for a bit longer if I was under 40 mph. If I tried to speed up to 50+ right away then it would start acting up sooner. That maybe equates to fuel demand issue?

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

If it is the pickup tube sock you will probably have remnants of it in the fuel tank. I would not run it without the sock filter. You may have to disconnect the fuel line at the pump, and at the sender and blow some air through the line to clear any debris out of it. Blow through the line at the tank end but make sure the line is disconnected at the pump. Yes, replace the carb filter too. once you remove the sending unit it will be pretty obvious if the filter is bad.....

https://classicparts.com/1967-87-gas...ock-filter-3-8

Edit: I didn't refresh the thread before I typed my reply so it mirrors the reply by 57taskforce... :( I guess great minds think alike... :)
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Re: I feel like I messed up bad - new to me truck issues after purchase
 

Yes, that’s exactly why I said to look for vacuum leaks(cheap and easy to find with carb cleaner), and really go over the fuel system. A vacuum leak leans the fuel mixture out, just like not enough fuel running thru the system, or a gummed up carb will do. I’ve seen the strainer get gummed up with old gas before, while not disintegrated, or falling apart it still had to be replaced.

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

With the age I wonder if I should just replace the whole tank and sending unit, or is that overkill?

Could I just put a fuel filter on the outlet from the tank

I will probably ask the shop to look at the sock and carb filter and replace it to get me going and then I can replace the tank and sending unit myself when I get it home

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

I remove the tanks, empty out as much of the gas as I can, and take them to the car wash and pressure wash them with soap, then a good rinse with clear water. I then take them home and vacuum out as much of the water as I can with the shop vac and put a heat gun in the sender/fill holes and run it until the tank is dry on the inside..... Works good. Then it is easy to tell if there is any heavy rust in them.
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Re: I feel like I messed up bad - new to me truck issues after purchase
 

My wife behind me thought it smelled like fuel and was running rich? Possible getting too much fuel.

I should have mention this too but I touched the coil to dist. cable while running and got a shock. Isnt it supposed to be insulated and that not happen? I was checking the plug wires were attached tight. The truck would sputter and backfire while under load too. - bad ignition coil and wires?

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

There is a lot of juice right there so if you are grounded good it will zap you through the coil wire..... :)

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

I bet a doughnut it’s running lean, backfires under load is a tell tale sign.

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

LIKE - this makes me feel a bit better and it might be an easy cheap fix.

I might just have a new HEI dist. and ignition sytem put in since they are fairly cheap. I am going to put on new plug wires with the ceramic boots and a fresh set of plugs.

It was also getting terrible fuel mileage.

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

When I brought old blue home.
Ran like crap.
Hei cap
Rotor looked even worse

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

Congratulations on your purchase. Don't panic. Sounds like you got the right truck. It may need some minor fixing, welcome to the tinkering. I suggest ask here on the forum lots of questions as they come up, and post lots of pictures of what you have and especially what you're asking questions about, and the fine folks here will give plenty of info to help you out and make recommendations if you want to hear them.

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

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

Thanks for the encouraging words. I did panic a bit and it was mostly because of lack of sleep and just spending a crap ton of money. My self-calming pice of mind is that these motors are fairly simple mechanical air pumps and there is not a lot of things to go wrong and it isn't anything major. In the IT world I am used to digital reliability not analog. Leaving a new purchase 100 miles away was tough too as I was planning on polishing it out tomorrow. Patience was never my strong point. It will all be ok and was probably a blessing that it acted up on me before I went up the pass.

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

I see you’ve got the NL2 aux fuel tank. You need to verify which tank it is pulling from. There should be a manual valve on the drivers floor near the bottom of the door, kinda between the door and the side of the seat. The valve will allow you to select between the cab tank and the tank below the bed. You won’t be able to properly diagnose this until you find out which tank it running on.

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

In your list of things to check you left off the obvious one to me.
Considering your elevation and ambient temperature it could just be carb icing.

I’ve had that happen. a few times.
Worst time I had an actual ball of ice around the carb.


https://en.wikipedia.org/wiki/Carburetor_icing

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

The 2nd tank was removed many years ago and the fill cap is just there for show.

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

Congratulations on your new truck! She a looker! :metal::metal: We'll be expecting more pictures of it.

Here is a link to a thread on fuel tanks. Post 20 has a good run down on the fuel tank.

https://67-72chevytrucks.com/vboard/...d.php?t=732963

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

Congratulations on your new to you truck. Try not to be disappointed in your purchase and embrace the truck for what she is. 50 year old and things are going to need attention. Our trucks are a hobby, not a daily driver. There are exceptions. Don't blame yourself or the seller. Whatever the failure, it may be that it failed for first time on the trip home. Think of it as a great opportunity to learn the truck. Lots more things will come. It is part of the "fun" of owning one of these. Hopefully you have a place and a little time to tinker. The journey can be rewarding and educational with the correct attitude.

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

Thank you, I need to also embrace even the suck parts of owning an old truck even if it looks good (kind of like marriage lol) I also need to just accept that there are no cheap hobbies I am interested in and it is better than sitting on a barstool all day and not having anything to show for it except regret. This is an eye opener of how as a society we have generally become used to getting in and turning the key and it working and having all the comforts of home.

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

Check all your rubber fuel lines specially on the suction side. My 68 would run fine at low speeds but at higher speeds or going uphill even at slow speed it would stumble . I changed all the filters and still the same . It ended up being the suction side of the pump . The rubber hose looked fine but was like mush. It collapsed under demand.