A few question about fuel delivery

[speedy]

I have a 82 c10 with a mild 350. It has the stock tanks, mechanical pump, and a quadrajet with broken choke(new one is next on my list). I have noticed it takes way too long for the engine to fire up. The carb and or pump is losing fuel. I can leave the truck for a few hours only to have to turn the engine over a 2 or 3 tries before it fires up. That usually consist of 5 second intervals.

I would like for it to fire up instantly or at least less than a couple seconds. I just don't want for it to eat my battery in the middle of town.

What would help with firing up faster? Is it the carb? Do I need to look into getting a new pump, possibly an electric pump?

While I'm here. I eventually want to redo my fuel lines from the pump to the carb. I also have a fuel regulator that I need to install but I have no idea where to put it. And lastly what type and size fuel line would be the best to go with?

Thanks

 

[bucket]

It's a carb issue more than likely. A stock quad is known to leak and a plug needs epoxied to fix it. It could also very easily just be an issue with your choke.

 

[chengny]

When you come back to the truck after a couple of hours, pull the air cleaner cover off.

While looking down into the carb throat, cycle the throttle linkage full stroke. Note whether or not you see streams of gas shooting down into the throat.

You should see it (gas spraying into the throat). If you don't, you either have a bad accelerator pump or - as Mr. bucket suggests - the plugs at the bottom of the float bowl are leaking.

Usually however the plugs don't leak so badly that all the gas is lost in a matter of 2 hours. And, since the entire bowl of gasoline has been dumped into the intake manifold, when the truck does start up, it runs extremely rich and you get big black smoke at the tail pipe.

Here is a little trick to easily diagnose an accelerator pump problem versus a leaking bowl:

First, pump the throttle a couple of times and try to start the engine normally. If it doesn't quickly catch, get out and spray a quick small shot of ether (starting fluid) into the carb or air filter.

Quickly jump back in the truck and crank it over again.

It if fires right up and continues to run normally, that indicates that there is plenty of fuel in the float bowl but the accelerator pump is not functioning correctly.

If it stumbles and stalls a couple of times before it starts running good, that points to a dry bowl.

 

[speedy]

Thanks for the replies guys. I'm not around the truck at the moment but will try those suggestions and let you guys know what happened.

 

[MadOgre]

Epoxy is only a temporary fix.

 

[speedy]

I drove the truck to work yesterday. Which is around 12 miles. It ran good other than some bogging when giving it more than half throttle. I'm not sure whats causing that. I have my secondaries adjusted but its possible the little spring is weak or broken.. Anyway I parked it and didnt touch it for about 4 hours. I popped the hood and check the fuel pressure gauge i have installed and it was still reading around 3 psi without the engine running. I removed the air cleaner lid and cycled the accelerator and it was shooting fuel like it supposed to. I left it there over night and did the same thing this morning and it still had fuel in it for it to fire up within a few seconds. Maybe it just needed running. IDK.. Regardless I still plan on swapping the carb and intake for a new one.

What do you guys recommend going with on the Carb and intake? Is 600cfm ideal for a 350 bored .030, 284 energizer cam, and a set of old camel hump heads.

Thanks

 

[bucket]

600-750cfm is fine, just as long as it's vacuum secondaries. And a dual plane type manifold.

I'd either go with a quality reman Quadrajet or an electric choke Holley. All depends on how much you want to spend and what features you want.

 

[farmerchris]

little known issue on quadrajet is which filter you use,use the correct length for the carb ,be either a short one or long one,not much problems on the short ones,that all that will fit in there.but most important is a quadrajet filter should have a small flap(valve)on the end going to the carb,this is a anti-drain valve.keep the fuel-bowl pressurized.cheaper or generic filter do not have this feature,and the good ones do not cost that much more.

 

[speedy]

little known issue on quadrajet is which filter you use,use the correct length for the carb ,be either a short one or long one,not much problems on the short ones,that all that will fit in there.but most important is a quadrajet filter should have a small flap(valve)on the end going to the carb,this is a anti-drain valve.keep the fuel-bowl pressurized.cheaper or generic filter do not have this feature,and the good ones do not cost that much more.

Hmm I'm not sure if that filter is still in the carb but I could be wrong.

 

[77 K20]

Hmm I'm not sure if that filter is still in the carb but I could be wrong.

I haven't run a filter in the carb for 20 years.... just run an external inline one. Had issues with the treads trying to strip out on it- so gave up on them.

 

[highdesertrange]

ok it sounds like your problem went away. 1st off there is no good reason for not running the filter in the carb. come on guys always use 2 wrenches when changing the filter, a 1" on the big nut and a 5/8 flare on the line nut. did I mention always, like never just try to use a 5/8, once the line is off break the big nut loose, this is the filter retainer once it's broken loose you can remove it by hand no wrench needed, replace filter and reinstall retainer by hand until it stops take your 1" wrench and snug, remember this screws in to the aluminum carb body you want it just snug don't do an Armstrong with your 1" wrench. then start your line by hand, when you can no longer turn it by hand put your 1" wrench back on and tighten your line nut with your 5/8 line wrench without letting the filter retainer move. do not try to tighten the 5/8 line nut without the 1" wrench in place. this is very important and where most people mess up. I will repeat "do not tighten the 5/8 line nut without the 1" wrench in place to keep the filter retainer from turning". also the carb bowl is not pressurized your carb bowl is vented though the charcoal canister. the fuel in there is not pressurized. highdesertranger

 

[77 K20]

ok it sounds like your problem went away. 1st off there is no good reason for not running the filter in the carb. come on guys always use 2 wrenches when changing the filter, a 1" on the big nut and a 5/8 flare on the line nut. did I mention always, like never just try to use a 5/8, once the line is off break the big nut loose, this is the filter retainer once it's broken loose you can remove it by hand no wrench needed, replace filter and reinstall retainer by hand until it stops take your 1" wrench and snug, remember this screws in to the aluminum carb body you want it just snug don't do an Armstrong with your 1" wrench. then start your line by hand, when you can no longer turn it by hand put your 1" wrench back on and tighten your line nut with your 5/8 line wrench without letting the filter retainer move. do not try to tighten the 5/8 line nut without the 1" wrench in place. this is very important and where most people mess up. I will repeat "do not tighten the 5/8 line nut without the 1" wrench in place to keep the filter retainer from turning". also the carb bowl is not pressurized your carb bowl is vented though the charcoal canister. the fuel in there is not pressurized. highdesertranger

And sometimes it just strips out for no reason. I just bought a quadrajet made by JET. Went to remove the fuel filter right off the bat. Used a 1" socket on the nut for the fuel filter. Broke loose easily. Turned it out slowly, and got it about 1/2 way off, then it started to not turn so easily. Turned it back in, and it got easier. Sprayed PB blaster on the treads, tried to remove it again. Started getting hard to turn. Sprayed it more. Ended up stripping out a few threads.

And I had a similar thing happen many years ago. Maybe I just have bad luck- but have heard of others having the same issue sometimes. There should be NO reason for it to strip when the fuel line is off.

And to support the likely hood if it stripping out, JET included a buy back paper in the box. If the your old carb is rebuildable then send it in. But if the throttle plate was too worn or loose, that would disqualify it. Also if the fuel filter was stripped out, then that disqualifies it also.

 

[MadOgre]

And sometimes it just strips out for no reason. I just bought a quadrajet made by JET. Went to remove the fuel filter right off the bat. Used a 1" socket on the nut for the fuel filter. Broke loose easily. Turned it out slowly, and got it about 1/2 way off, then it started to not turn so easily. Turned it back in, and it got easier. Sprayed PB blaster on the treads, tried to remove it again. Started getting hard to turn. Sprayed it more. Ended up stripping out a few threads.

And I had a similar thing happen many years ago. Maybe I just have bad luck- but have heard of others having the same issue sometimes. There should be NO reason for it to strip when the fuel line is off.

And to support the likely hood if it stripping out, JET included a buy back paper in the box. If the your old carb is rebuildable then send it in. But if the throttle plate was too worn or loose, that would disqualify it. Also if the fuel filter was stripped out, then that disqualifies it also.

Sounds like JET is a place to stay away from for rebuilt carbs because both of those issues can be fixed better than new with the right tooling which would be peanuts for a large company like JET to invest in.

And im still scratching my head trying to figure out how a freshly rebuilt carb would have that kind of issue with the filter nut. Unless there are real monkeys building carbs at JET.

I would just send it back and demand another one!

 

[350runner]

What a shame :-(

Sent from the dust in front of you!

 

[speedy]

It's been starting up with no issue at all. Even this morning, after sitting for a few days it fired right up. We just did a Fast ez-efi fuel system setup on a 85 k10 today at work and I have to say it is NICE! I'd like to go that route and be done with it but at $2k it's a little deep for my wallet right now.