Running out of fuel

[Monte123]

My initial problem was that it would run out of fuel at wot, now it it a runs out of fuel after a couple miles, crank it over for a few times and its good for about a half mile. 

Its a 402 5 speed with a 2 line fuel pump. The new issue started after the car sat for about a year. 

Any suggestions? I have replaced the carb, fuel pump and filter with no change

[Dtret]

Silly question but is the gas good? Check all the rubber connector lines and make sure that they are not broken down internally. Should only be two on the sender and two on the fuel pump. 

[Monte123]

Gas is fresh, ever heard of the strainer getting plugged?

[cny first gen 71]

8 minutes ago, Monte123 said:

Gas is fresh, ever heard of the strainer getting plugged?

Yes i have if there's any rust or debris in tank can plug up strainer. 

[Monte123]

If the strainer is plugged,  whats the best way to clean the tank?

[cny first gen 71]

Have to pull tank and sending unit and look at it then look in tank to see what it liiks like. Possibly a borascope in through gas tank neck not sure how that would work.

[Rob Peters]

Is there a filter inside the carb where the fuel line connects?  My original Monte 4brl had a filter in there that would sometimes fill with debris and cause a smart issue.  Also issues under a load such as going up a hill.

rob

[72-CLASSIC_RIDE]

I had a 69 Chev P.U. that when I gave it gas under load, the engine kept dying.  After considerable investigation discovered a plastic like bread tie between fuel and Carb Fuel Filter that would choke off fuel.  Crazy how it got from fuel tank to Carb.

Doug

[Monte123]

I have replaced the carb, fuel filter and fuel pump, the rubber line from the frame to the pump is good, guess the tank is coming out. Should I siphon the tank first? Has a half a tank. 

[cbolt]

Siphoning the gas would be the first step

 

[Chevy Dave]

I had a problem with fuel starvation at full throttle. I replaced the carb inlert fuel filter and it cured the problem.

[Scott S.]

Just to mention...

If it sat for a year, there is the possibility of the diaphram in the fuel pump weakening/rotting out. 

[Monte123]

Thanks for the input,  I still haven't figured it out, will keep looking 

[Scott S.]

👍

[BobW]

I had a Chevy van that somehow got a hole in the fabric strainer on the fuel tank pickup. It would intermittently clog and starve the carb. Definitely drain the tank before you remove it.

[420ponies]

I would invest in a new gas cap before I drop that tank.Seems that could be the problem to me. Little money across the counter for an easy fix. Also that filter in the carb only goes in one way. Almost forgot, anything leaking on your lines coming from the tank? It would be wet in front of the tank where the rear axle is.

Edited August 11 by 420ponies
added content

[Monte123]

I haven't seen any leaks so far, I tried running without the cap and there was no difference.  I am going to put a small gas can under the hood and run a line straight from it to the pump to see if that makes a difference.  

[420ponies]

Yours is a '72 Monte, correct ? Running it without a cap, does not do anything to it really. A closed/working cap ,sends the vapors up into the "can", located behind the rear seat. You have 2 lines for that system I believe, plus 2 vent lines on each side of tank. If any of those lines have any dry rot/cracks, that will cause the problem you are having. Known as vapor lock, air is getting into your feed line and causing the running out of fuel. I would check/replace those hoses first. 53 yrs is quite some time for fuel hoses to last. Mine are going on 17yrs, and are being replaced when I change tanks for EFI, regardless on how they look. Preventive maintenance does pay off.

[stangeba]

I replaced all the rubber hoses on my 71 several years ago just as a precaution. I did find a restrictor in one of the hoses that I almost threw out. I wrote about it some time ago and I don't know if a 72 has this or if the previous owner messed everything up.

[Monte123]

So, what im hearing here is, drop the damn tank, lol. I appreciate all the help, was really hoping for an easier fix. Yes I know its not difficult to drop the tank, had it out 10 or so years ago but I was in better shape then 😂. On another note, we had a rat problem last fall/winter, they could have gotten in there and messed things up too.

[Scott S.]

There's a simple solution to a rat problem.   

Get it inspected on a regular basis.  

[1970mcss]

Speaking of gas tanks. I'm finally going to replace my tank with a vented tank and possibly add the vapor trapper if the car still stinks like gas. I'm thinking about getting the tank with 2 ports unless there is a reason to go with the 3 port tank. Who is the go to for a new tank??

 

 

[DragCat]

10 hours ago, Monte123 said:

 On another note, we had a rat problem last fall/winter, they could have gotten in there and messed things up too.

Yep rats/mice can wreck havoc on autos 🙃

[DragCat]

5 hours ago, Scott S. said:

There's a simple solution to a rat problem.   

Get it inspected on a regular basis.  

Better approach, and a back in the day (yea that's my Montego) 

 

[Scott S.]

22 hours ago, 1970mcss said:

Speaking of gas tanks. I'm finally going to replace my tank with a vented tank and possibly add the vapor trapper if the car still stinks like gas. I'm thinking about getting the tank with 2 ports unless there is a reason to go with the 3 port tank. Who is the go to for a new tank??

 

 

In your neck of the woods, Parts Place would probably be the closest.