I need help getting my trucks engine running!!

[1968_K20_4x4]

I will check for 12v to the distributor next

[1968_K20_4x4]

So I installed my new carb yesterday. I poured gas down the fuel line untill the filter was full and she stopped taking more gas. I tried to fire up the truck and she wouldn't go. At first she cranked and sounded really good like it would go. It fired up and ran for a couple seconds then died. I poured some more gas in the fuel line and tried a few more times but it would just turn over but wouldnt fire. I checked and I do have 12v power to the distributor with the key on. So not sure where to go next with it.

My uncle has worked on old trucks for a long time. I usually try to figure stuff out on my own but I asked him to come down and see if he can help me figure out what's missing.

Thanks guys for all your help thus far. I certainly know a lot more than when I started. If anyone has any other ideas of what else to check please let me know. I'll update with how me and my uncle make out

[min]

Are you sure the fuel pump is working. Pull the fuel line off the carb and crank it over to see if you are getting fuel.

[1968_K20_4x4]

So I finally got the truck running! When my uncle came down yesterday we traced back and found the problem... the sending unit was clogged! I had blown out the rest of the fuel lines but didn't think to check the sending unit. Cleaned it out and when we put it all back together she fired right up! Thanks again to everyone who responded, I learned a lot from all your replies and now thanks to your knowledge and help there is one more old chevy truck up and running! Lots more work to do ahead of me but I couldn't be happier with this progress. You guys are awesome. Thanks again

[68 P.O.S.]

Good work figuring it out. Now you need to throw on a fuel pressure regulator set to 5.5.psi to keep the Edelbrock from flooding.

[Ol Blue K20]

I'm glad you got it figured out.

[1968_K20_4x4]

Originally Posted by 68 P.O.S.

Good work figuring it out. Now you need to throw on a fuel pressure regulator set to 5.5.psi to keep the Edelbrock from flooding.

Thanks for that info, this will be my next step. Ordered the Edelbrock unit

[wesmigletz]

Originally Posted by 1968_K20_4x4

Thanks for that info, this will be my next step. Ordered the Edelbrock unit

I would switch to a low pressure pump rather than run a regulator.

Carter M6120
https://www.summitracing.com/parts/crt-m6120/overview/

or

M2468
A bit pricier, but this is a higher volume pump. I run this pump on my performance SBCs running Holley carbs.
https://www.summitracing.com/parts/crt-m2468/overview/

[1968_K20_4x4]

Originally Posted by wesmigletz

I would switch to a low pressure pump rather than run a regulator.

Carter M6120
https://www.summitracing.com/parts/crt-m6120/overview/

or

M2468
A bit pricier, but this is a higher volume pump. I run this pump on my performance SBCs running Holley carbs.
https://www.summitracing.com/parts/crt-m2468/overview/

This is a way better idea! Forget the pressure regulator. This is absolutely a much better way to go. I didnt know such a thing existed. Thank you for this awesome suggestion! Ill definately be returning that regulator and buying a low pressure pump instead.

[bill3rail]

Originally Posted by 1968_K20_4x4

So while I wait for my new carb to arrive I have a couple little updates. Checked the casting number on the block and it checks out to be a 69-73 307 2 bolt. Also, pulled a few spark plugs. Not sure if you can tell if they're good just by looking at them. They're very dirty and one had oil on the thread. Here's a couple pics of the plugs for your consideration

Check those plugs. Unless my eyes are deceiving me, that bottom plug looks to be different than the top two.
The top two are definitely tapered seat plugs but the bottom one does not look the same to me.

Time for new plugs anyhow.

Bill

[68 P.O.S.]

Originally Posted by 1968_K20_4x4

This is a way better idea! Forget the pressure regulator. This is absolutely a much better way to go. I didnt know such a thing existed. Thank you for this awesome suggestion! Ill definately be returning that regulator and buying a low pressure pump instead.

Get the Edelbrock 1721 fuel pump. I'm using it with my 1406 and it works great. Just a little pricey, but made to work with their carbs.

[OregonNed]

Originally Posted by 68 P.O.S.

Get the Edelbrock 1721 fuel pump. I'm using it with my 1406 and it works great. Just a little pricey, but made to work with their carbs.

Second that - my set up and it works great

[1968_K20_4x4]

Thanks Guys. I bought a Carter M4685 mechanical pump... the listing says it runs to a max of 7psi but a bunch of reviews said it worked really well with an Edelbrock carb. Going to try that out and hopefully it will work good

[1968_K20_4x4]

In the meantime here is a couple pics of the truck all cleaned up. Really loving that ochre colour!

Sorry about the tire covers

[1968_K20_4x4]

Pic 2

[68 P.O.S.]

Nice looking rig. Which seats are you running?

[1968_K20_4x4]

Originally Posted by 68 P.O.S.

Nice looking rig. Which seats are you running?

Thanks!
Theyre some type of generic bucket seats that came in the truck. No idea what they came out of. Ill upload a pic- sorry about the messy interior this was when I just bought the truck. Theyre OK for now, eventually I would like to install a bench seat from an early 90s GM truck

[1968_K20_4x4]

Originally Posted by bill3rail

Check those plugs. Unless my eyes are deceiving me, that bottom plug looks to be different than the top two.
The top two are definitely tapered seat plugs but the bottom one does not look the same to me.

Time for new plugs anyhow.

Bill

Thanks for the suggestion. All the plugs I pulled were tapered seat, the picture isnt great but the one plug had some oil on it when I pulled it making it look different from the others. All plugs have since been replaced with new ones

[1968_K20_4x4]

New fuel pump is installed. Truck fired right up and is running great! Thanks so much for all the help guys

[Ol Blue K20]

Congratulations!! It must feel good

[68 P.O.S.]

Congrats!!!

[cknfrmr]

Congratulations! Happy Motoring.