Engine shutting off

[Aviodont]

Background:

-83 k5 305 auto

-Out of commission 9 months due to being too lazy to do drum brakes during the summer

-Finished drums yesterday despite 81 degree heat. Bled this morning

I was going to take it for a test drive today to check the brakes, so reconnected the battery but it wouldn’t start.

It is normal for it to have a hard time starting if it sits 10 days or more. I can see that there is usually fuel evaporation in the see through fuel filter. Normally it is 50%+ full while running, but if it sits , it goes down to about 25%. So, if it has been sitting, I have to “assist” by either putting a little carb/choke cleaner in or if I have gasoline I will put a little in the carb. Usually starts up right away and the fuel filter fills up to its normal level of half full in about 3-4 seconds and it runs normally. If it is turned on every day, it starts up without “assistance.”

But today (only six weeks since last started), carb cleaner barely got it to turn over but it would shut off in 2 seconds. If I poured gasoline in, it would run for ~10 seconds, then shut off.

In the last 9 months, I have probably started it at least every 4-6 weeks. The last time was 6 weeks ago and, after the “assistance” described above, it started without any problems at that time.

My initial thoughts….

1) I doubt it is out of fuel, because the fuel filter is about 20% full (fuel gauge is inaccurate).

2) could be old fuel issues (fuel is 9 months old), but it started in the normal “assisted” manner just 6 weeks ago just like it had been all along all those months. It would seem strange for fuel to be working for 7+ months just fine, then its quality dropped off precipitously in the last 6 weeks

3) fuel pump not pumping

4) fuel pump or lines gummed up

Thoughts?

 

[Wes Harden]

how many times did you try adding fuel to carb before you quit ? I just went through this with my dads Ranchero. It took at least 6 tries. I was adding fuel into bowl through bowl vent.
After it starts normally.
6 weeks is enough time for maybe a fuel hose to fail or be a victim of rodents, I'd give them a look

 

[Aviodont]

how many times did you try adding fuel to carb before you quit ? I just went through this with my dads Ranchero. It took at least 6 tries. I was adding fuel into bowl through bowl vent.
After it starts normally.
6 weeks is enough time for maybe a fuel hose to fail or be a victim of rodents, I'd give them a look

I must have tried 8 times with fuel and 3 times with carb cleaner. BUT, that assistance was only to get it to start to turn over, not to continue running. In other words, I didn’t try to run out of the truck before it shut off to add more gas into the carb. Should I have done that?

I hope it was not a rodent problem because it was in my garage. I haven’t seen any signs of rodent activity. Of course one can never be sure, but it would be hard especially with the cat lady next door and she lets her cats roam through everyone’s yards, defecating as they please.

EDIT: actually I am almost certain no rodent because we had plastic sealed bags of walnuts pecans and flour in the garage which they certainly would have tried to get to first. So if a fuel line failed, wouldn’t the garage have reeked of gasoline?

 

[Aviodont]

I must have tried 8 times with fuel and 3 times with carb cleaner. BUT, that assistance was only to get it to start to turn over, not to continue running. In other words, I didn’t try to run out of the truck before it shut off to add more gas into the carb. Should I have done that?

I hope it was not a rodent problem because it was in my garage. I haven’t seen any signs of rodent activity. Of course one can never be sure, but it would be hard especially with the cat lady next door and she lets her cats roam through everyone’s yards, defecating as they please.

EDIT: actually I am almost certain no rodent because we had plastic sealed bags of walnuts pecans and flour in the garage which they certainly would have tried to get to first. So if a fuel line failed, wouldn’t the garage have reeked of gasoline?

Ok, so I went out this morning and did the gasoline thing again. This time, it hung on, idling roughly, but I stood by ready to add fuel. But I didn’t because, for a good 4 minutes there were flames about 2 inches high wafting out of the carburetor. I went and turned the garden hose on just in case because I couldn’t remember where my fire extinguisher went. Well it eventually died out. I let it run for ten minutes and the fuel filter eventually filled to almost 50%z. Then I Shut it off. And restarted. It restarted rough, but stayed on.

I will restart later today to see if there are any issues. Was four minutes of flame too much?

To take my own thread in a little tangent. Can the tailgate window be manually lifted. Mine is 3/4 up and won’t go anymore. You could hear the motor straining the last 2 inches. And we have rain coming today.

 

[rampage]

To take my own thread in a little tangent. Can the tailgate window be manually lifted. Mine is 3/4 up and won’t go anymore. You could hear the motor straining the last 2 inches. And we have rain coming today.

Yes, remove the panel on the tailgate. There's a cable that goes from the motor to the regulator. Disconnect it from the motor and insert the end into a drill.

 

[Aviodont]

Thanks.

I watched a few videos and got it. I ain’t ever opening that thing again!

I’ll let y’all know how it goes with the restart later today.

 

[Bent77]

Not uncommon for the fuel lines down the rail to pin hole

You’d never smell fuel, but it won’t get 100% suction to fill the pump and filter
Also the sock in the tank will slow the fuel charge if it’s dirty

 

[Wes Harden]

I have had fuel evaporate out of vented tank on dune buggy over the summer.
Old rubber fuel lines is my guess, as Bent said pin hole or crack.

 

[ZooMad75]

Ethanol laden fuel does seem to evaporate easier than non ethanol fuel. Not to mention the crappy short shelf life of fuel with ethanol in it.

Don’t stress on if the fuel filter is full fuel or not. Typically if it’s running you will see half to 1/3 fuel in it. That’s ok.

Between fuel evaporation and crappy quality of old fuel I’m betting that’s where the struggle starts. I’d get some fresh gas in it and reevaluate how it runs.

Bent is also spot on for a pinhole in the rubber lines between the pump and the tank. It will struggle to draw fuel, but can maintain running once you finally get it. But if you let it sit for a couple of days the system will loose prime and have you start all over again.

 

[Aviodont]

So it started fine the next morning after about 20 hours. No hesitation.

I wonder what it was.