Fuel issue
 

Howdy all, my son ran into another issue that I am going to post to get some opinions on. His truck is a 1969 C10 with a 305 engine and a 4 barrel carb. The other day, he stalled out driving around the house. He was able to get the truck started again, but I guess it stalled out again. He was able to get off the road and we had it towed home. It kicks over, and when I put gas into the carb it will run, but will die once that gas is used up. He bought a new fuel pump, he works at a auto parts store so it was a cheap part to try. That did not work. He disconnected the lines at the fuel pump and said he is getting gas to the inlet and outlet, but once he connected the line to the carb the fuel is not getting to the carb. I ask him, and he swears there is gas in the tank. My question, and I have had to work so I have not really had a chance to look yet, what could cause the gas to go thru the pump, but not get up the line to the carb? He took the line off the carb and blew air thru it and said it was not plugged. It is a standard fuel pump, not electronic, and the gas tank is still in back of the seat.

I am more just looking for suggestions because I have been working and he is doing this on his own. I think he may be out of gas and does not want to tell me, but if he is getting gas thru the pump that would tell me there is gas in the tank. Any suggestions on where I should start?

Thanks in advance

RR

Re: Fuel issue
 

There should be a small filter in the fuel inlet on the carb. It may be plugged up. Tell him to be very careful when he screws the fitting back into the carb because they have very fine threads and are easy to cross thread and/or strip the threads out in the carb or fitting. If I remember correctly it takes a 5/8" wrench for the line and a 1" wrench for the fitting. He may have to use a wrench on both to get the line broke loose.

LockDoc

Re: Fuel issue
 

What brand and model of carburetor?

Re: Fuel issue
 

Thanks for the suggestion. I was thinking about that, but wouldn't the gas still come thru the line into the filter you are talking about? He bought a clear external filter and I don't think there is any gas even getting to that. I am planning on attacking it this week after I get out of work.

I will let him know to try it, why not, right?

Re: Fuel issue
 

I am not sure, it was on the truck when he bought it and I have not looked to see. I am going to guess Holly, or whatever came stock on the truck, but I will check it and see. Thanks for the input.

Re: Fuel issue
 

an inline filter i use a metal canister ones i dislike the plastic ones
Look under the truck for a filter many ppl have put one before the fuel pump


You can remove the sending unit check the pickup sock is clean and look inside the tank with a flashlight To look at and for sludge in the tank and use a bucket to put the sender unit in

I would remove the seat put some plastic down to keep any spilt gas of the carpet or underlay

You can use a long stick ex yardstick to stick in the tank for a dip reading to see if there is gas in the tank in case the sending unit or guage failed and stuck on a reading

Re: Fuel issue
 

Stuck carb. inlet needle?

...wait a minute, you say he tells you (post # 4) that fuel is coming out of the pump but..." He bought a clear external filter and I don't think there is any gas even getting to that."

That don't sound right.

Re: Fuel issue
 

If the inlet filter was plugged it might not let the clear filter fill up. It will be interesting to see what the problem is when you guys get it figured out.

LockDoc

Re: Fuel issue
 

There is a "sock" in the fuel tank from the factory on the bottom of the fuel line. This can collapse and give you this condition.

Re: Fuel issue
 

I towed a guy off the highway and helped him with a similar issue...
he had just installed a "new" fuel pump so I assumed it was good....
I pulled the line off and checked for flow...had some but not great...
then I pulled the sender and sock out...it looked fine.
Turns out...his "new" pump was bad right out of the box

Re: Fuel issue
 

I call that a BOOB...Bad Out Of Box.

I think others have said this, but start at the carb and check for fuel pressure. Disconnect line at carb inlet, place in suitable container and crank engine. If good fuel flow, then it is a carb issue. If no fuel flow or very weak, start working backwards. On my '72 240z, I purchased two fuel pumps in a row that did not work. Did your son install the pump correctly (meaning cam follower is pressing properly on pump lever arm). Could there be a cracked or split hose on the suction side of the pump? If so, the pump will suck air and not fuel...but you should get some fuel.

Last week, I had to rebuild the LP side of the fuel system on my CC boat with a PCM GT-40 (ford FI) engine. It was confounding because the LP pump was running, but no fuel to the HP Fuel Cell Canister. I went ahead a replaced all the fuel components on the LP side of the equation including: fuel pump relays, in-tank pick-up tube (to eliminate vacuum leak), and LP pump. I suspect it was the LP pump (even though it was running on key on priming cycle).

Good luck.

Re: Fuel issue
 

U have a lot of good suggestions here. Yardstick would b my first move ,just to see how much gas u really have. U might want to pull the line off on the outlet side of the fuel pump. Then crank it. This will show how good that new pump is. U should get a good stream coming out. If u still have the Quadra jet on, then Locdoc is right. That original filter is fine so u will need to replace it. Even if your clear filter is before the original, u can still have a problem due to all the pressure built up from clogged filter. This would not let the gas flow thru your clear filter. (Think action...reaction). If u do indeed have a filter before the pump, it’s clogged at least to some degree slowing down the available pressure needed to pump to carb. Good luck and keep us posted.

Re: Fuel issue
 

Now that's a conundrum.....I like "BOOBS"...:lol:

Re: Fuel issue
 

https://www.youtube.com/watch?v=AynXoLjYrKc

:lol:

Re: Fuel issue
 

I was chasing an issue like this recently and it ended up being a bad HEI module. Not sure if you have an HEI installed, but it’s worth mentioning.

Re: Fuel issue
 

I don't think I saw this, but I was having the same issue one time and I put a jug of gas with the supply side hose into it (disconnected the hose from the pump and installed a long hose on the pump to reach the jug) to see if there was a block before the pump. In my case there was, so I got lucky that I figured it out before I started throwing parts at it - which I have been know to do :rolleyes:

Re: Fuel issue
 

Thanks to all who replied. After having him disconnect the lines at the carb and at the fuel pump, and see if gas was getting thru, I had him pull the sending unit. Guess what? It was dry when it came out. So I had him put a piece of pvc that I had laying around, down the tank and low and behold that was dry too. So, I told him I thought he was out of gas. He still swore that he put gas in it, but I showed him that there was no gas on the pvc pipe. I sent him over to the gas station with a two gallon gas can, put it in the tank, and damned if the thing didn't start right up. Lol. He just bowed his head. I told him, Son, you haven't made a mistake that your daddy aint made when he was your age. Now, we learn and move on. I told him, it cost him 20 bucks for a new fuel pump and filter, but he learned a valuable lesson. We had a good laugh, he went and got gas and all is good. Thanks to all who replied and gave me good info. RR

Re: Fuel issue
 

-
Yep, been there, done that...:)

LockDoc

Re: Fuel issue
 

Its a good learning experience for him need to check if the gage reads properly when he fills up

Re: Fuel issue
 

I'd say that more of us over 50 have been there at least once in our lives.

Reminds me of my best friend's wife saying that the gas from the station across the road from my house wasn't any good as she didn't get the same mileage with it as she did with gas from another station a few miles away.

Jim asked how much gas she put in and she said 10 but it won't go as far as 10 dollars goes on gas from the other station. Gas across from my house was 60 cents a gallon more than the other station. That Cute old T pot gas station now sits in a park in town where it is popular to pose your car or truck in front of it and take a photo.

I ran out of gas 3/4 way down the quarter mile at the drag strip in my 48 one night at the Street rod drags because I had miss guessed how much gas I had. I was winning too.,

Re: Fuel issue
 

Yeah, that happens with kids. I worked as a mechanic many years ago, and some guy had his kid's car towed to our shop, saying to give it a tune up. One of the other mechanics put all the parts on, and then it still wouldn't start. He left me a note, for when I came in the next day. I checked it out. Spark, no fuel. The thing got towed because of no fuel. I put $2 worth of gas in it and got it started, and called the customer to come get their car. When I told the kid that it was out of gas, he got all chesty and accused me of trying to rip him off- "I put $2 in it a couple of days ago!". I laughed, and told him that 1 gallon of gas isn't a rip-off, and that he ought to pay more attention to his gas gauge. His dad wasn't happy, either! :lol:

I can't fault the other guy for just changing the parts in this case, because it wasn't running and he was told to do a tune-up by the customer. By that time, I had learned my lesson (with a customer that said "replace the carburetor", which, of course turned out not to be the problem) and relied on my own diagnoses after that.

Re: Fuel issue
 

Yep, that was about how it went. lol

Re: Fuel issue
 

As much as I wanted to do that, I wanted him to do it and figure it out. He did ask me to help, and that is when I got involved. Once I told him it was out of gas, he just bowed his head and said "****" under his breath. I knew he felt bad enough as it was, so I just told him that he hasn't made a mistake yet that his old man, or his grandfather for that matter, have not made at least once. So, we learn and we move on. LOL. He, like me, has a habit of getting himself into stuff and then not knowing exactly how to get out of it. But, he is learning.

Re: Fuel issue
 

And before anyone suspects that I think I can walk on water, I've run out of gas, too! :lol: I can walk on water, but it has to really cold out.