Picked up my first classic truck

[BabyBlueChevrolet]

I recently bought a 1973 Chevy Cheyenne C20. Its got a 350 small block and TH350 trans. When I bought it I drove it 250 miles back home. It was doing good then it started backfiring on the highway.

Anyway this is my first classic truck and Im real excited to get her running perfect. It is definitely a project but all the major parts are there. The engine runs like crap at the moment, might need a rebuild.

I am more familiar with 90s chevy trucks and dont know a whole lot about these, so any help yall can give me would be awesome.

You must be registered for see images attach

You must be registered for see images attach

 

[Asgeir]

Nice find, welcome from Oklahoma!

 

[oldretiredafguy]

Welcome from N. Texas!

You must be registered for see images attach

Sounds like it may be as simple as old/bad gas. Drain out as much as you can get; replace the fuel filters, and buy a couple cans of Sea Foam. Works wonders on gunked up fuel lines, carbs, water in gas, etc. Might also want to search for ethanol free gas.

 

[BabyBlueChevrolet]

Welcome from N. Texas!

You must be registered for see images attach

Sounds like it may be as simple as old/bad gas. Drain out as much as you can get; replace the fuel filters, and buy a couple cans of Sea Foam. Works wonders on gunked up fuel lines, carbs, water in gas, etc. Might also want to search for ethanol free gas.

I filled it up with mobil 1 gas premium then put a few gallons of regular. Before that it seemed to be running just ok. What gas stations have the lowest ethanol?

 

[oldretiredafguy]

Someone please correct me if I'm wrong, but I think all "normal" fuel has the same ethanol percentage, regardless of location (mandated by our smarter than us peons-Federal regulators). That's why I recommended looking for ethanol free. Costs more than "normal" fuel, but well worth it with no ethanol getting near your rubber lines or carb gaskets.














'

 

[Randy and Easton]

Welcome from DFW Texas. We agree with @oldretiredafguy , start simple fuel, fire and air and go from there. These trucks are easy to work on and there are some great folks here with tons of experience! You will learn a bunch like we have.

Randy and Easton

 

[Strick]

Welcome from Central NC.

Strickland

 

[chris_n]

Someone please correct me if I'm wrong, but I think all "normal" fuel has the same ethanol percentage, regardless of location (mandated by our smarter than us peons-Federal regulators). That's why I recommended looking for ethanol free. Costs more than "normal" fuel, but well worth it with no ethanol getting near your rubber lines or carb gaskets.

I believe out here in CA it is 10% ethanol. It ate up my OEM GM fuel pump in no time. I agree, if you can find ethanol free, get it.

 

[Shorty81]

Welcome from Ohio

 

[BabyBlueChevrolet]

Thanks for the warm welcome everyone Im real stoked to finally have the truck ive wanted since high school. I got alotta learning to do about carburetors but everything else under the hood seems super simple and there is ample space to work

 

[oldretiredafguy]

I filled it up with mobil 1 gas premium then put a few gallons of regular. Before that it seemed to be running just ok. What gas stations have the lowest ethanol?

Sounds like the new fuel you pumped into the tank stirred up all the garbage sitting on the bottom of the fuel tank. May be worth your while to look into another tank (new or used). Other option is to pull the existing tank and clean it like you do to your little one's high chair. Regardless of your method, filters will still need to be changed out. Pulling the tank and cleaning it out will insure you only have to change filters once.

 

[BabyBlueChevrolet]

Sounds like the new fuel you pumped into the tank stirred up all the garbage sitting on the bottom of the fuel tank. May be worth your while to look into another tank (new or used). Other option is to pull the existing tank and clean it like you do to your little one's high chair. Regardless of your method, filters will still need to be changed out. Pulling the tank and cleaning it out will insure you only have to change filters once.

Will do, thanks for the lead. Also, the transmission doesnt shift automatically, I have to start in low gear then shift up to second at just the right moment and same with third. I looked underneath and found a small bell shaped device at the back of the transmission, it seems like a vacuum operated solenoid of some sort and it is disconnected. Could this be the reason why it is not shifting automatically?

 

[WFO]

Welcome from the Texas Panhandle.

 

[ChuckN]

Will do, thanks for the lead. Also, the transmission doesnt shift automatically, I have to start in low gear then shift up to second at just the right moment and same with third. I looked underneath and found a small bell shaped device at the back of the transmission, it seems like a vacuum operated solenoid of some sort and it is disconnected. Could this be the reason why it is not shifting automatically?

Welcome! That thing that you speak of should be hooked up to manifold vacuum, it is called the vacuum modulator I believe. There should be some kind of steel line around the passenger side with attached rubber line that will connect to that modulator and likely to a port on the carb. And yes with that disconnected, it will definitely affect transmission shifting.

As far as ethanol free gas, just do a quick google search for your town for “ethanol free gas in blah blah” and it should come up.

I agree with the suspicion of bad gas and or clogged filter. I don’t know if it’s recommended, but I’ve seen Derek from Vice Grip Garage and Frieburger from Roadkill temporarily put a longer rubber hose (stressor on temporary) from the pump to the carburetor and put in-line a series of Wix clear plastic (not glass) fuel filters. As they clog up from the crud, the one nearest the tank will get really dirty and clog…so they stop and remove it, and reconnect it to the next one in-line and continue on until it finally clears.

I don’t know if I’d do that….but I understand why THEY do. Good luck with the truck- lots of good, helpful people here.

 

[Mr Clean]