Vapor Lock - possible Pump issue TBI 350 (1 Viewer)

[Isotel]

I Ran the Independence Trail System on July 4th , and Tword the end of the trail i was having an issue with Vapor and fuel Spitting out of my Vent for my Gas tank.. then the truck stalled out and would not start for 10 min or so.. ( No fuel from the Injectors).. The Pump was hot, but i could still grab onto it without burning myself..

My Tank Vent is currently run from the old 3 emissions holes up the roll bar..

Ive had No issues Previously with the fuel system, ive been DDing the truck for atleast a month.. But it was hot down in the washes of the trail!

The issue happened again half way home right as a Rain/Hail Storm moved thru

any ideas? Im going to get a new Fuel Filter. and put in some injection cleaner tonight..

And Some photos from the trail

 

[Isotel]

Some info on the Pump/line system

Pump Sits under the Tank. The Lines are run far away from the exhaust.. Im using the factory GM lines to the pump with a short rubber hose to the P5001 Carquest External Fuel Pump.. Small Pre Filter before the pump

 

[Isotel]

Any Ideas?? BUMP

 

[FJBen]

Any Ideas?? BUMP

On my old Heep i did the 4.0L swap and used an inline pump...same setup, away from everything...It still vaporlocked when it was ~100 degrees...never figured it out.

My friends CJ with a 4.3 and inline pump has done the same thing...he's running a small primer pump as well.

honestly I'm not sure how you get around this other than a surge tank setup. Thats why the intake pumps are nice as the fuel cools them and stops the cavitation issues.

 

[Isotel]

Thanks Ben, So, the issues ive been having is considered Vapor Lock?? just before it died on me i had LOTS of vapor and some gas coming out of my vent..

 

[FJBen]

Thanks Ben, So, the issues ive been having is considered Vapor Lock?? just before it died on me i had LOTS of vapor and some gas coming out of my vent..

Is your gas cap vented? I bet if your opened your gas cap it would really "suck" ;p Or if it starts to vaporlock or "cavitation" occurs...open your cap...see if it helps.

 

[Isotel]

will do, i think my cap is not vented.. i dont think it builds up pressure or vaccume.. but i will try that next time!

Trevor

 

[bustanutley]

did you make the exit of patriot?

 

[Isotel]

did not make the entrance! lol We ran Liberty.. Patriot looks like a BLAST!

NEED a cage still!

 

[nanuk]

We need to talk about your fuel problem!
Lets just say on the way back from Blanca one time, I was stopping every 10 mile or so to ice the fuel pump.
And speaking of fuel pumps, I have been through a few.

One question, does your engine temp rise when this occurs?

I just gave up for the night on getting the 40 done for tomorrow, so I may show up in the 80.

And we will have to talk about your fuel problem.

 

[Brian in Oregon]

If the cap is not vented, is the tank vented? If it builds up vacuum, it could prevent fuel flow.

Check out Edelbrock for high pressure electric fuel pumps.

 

[CruisinTiger]

Hey I had the same problem with my 60 a few years ago. I bought some pipe insulation that is sticky on one side. Wrapped the metal fuel line in the engine with it and never had vapor lock again. Works like a charm. Good Luck

 

[Brian in Oregon]

BTW, the installation of a small mechanical fuel gauge and a clear fuel filter, both rated for your fuel pressure, will tell you a lot about what is happening with your fuel system.

Normal operation will be a full fuel filter and rated fuel pressure of your pump.

Vapor lock will show as an empty fuel filter with rated fuel pressure of your pump. That's because you have pressure, but the gasoline has turned to vapor.

Vacuum lock in the fuel tank will show as either a partially or full fuel filter, but little or no pressure.

I installed this setup on a pickup of mine that was having chronic vaporlocking, and resolved not one, but several sources of vaporlocking. It's a great diagnostic tool.

 

[Isotel]

A bit of an update, I do not think this was a vapor locking issue.. It happend to me again on the way to Holy Cross City.. Pump and lines where not that hot!, i was going to swap out fuel pumps, but i realized that i had no fuel feeding into the In line on the pump.. Tank must have been plugged up with something!, Cleaned it out and replaced the old Toyota OEM line with new stuff.. Time will Tell if it fixed it!

I think that the Pump would get plugged causing a Lean condition and thus my Overheating isssues!

 

[venpick]

Wow I see this is a really old post. 2007. But I just have to say hi and post because I just had similar problems when running the wheeler lake trial in Co. a few weeks ago. And, I couldn't help but notice that our 4-Ds look the same so.... problem solved yellow cruiser with v8 venting fuel out of tank causing vapor lock type symptoms. Just need to paint it a different color than mustard P. . LOL . Seriously though I had a very similar problem. Fuel was spewing into the cab from the vent then with no previous problems of vapor locking ever and lots of testing. It stalled out and would not restart until i manually vented the gas tank by taking off the cap, and tapped on the fuel pump, scratched my head, and kicked a tire. (I dont know if any of that did anything but it would restart once I did that) It died a few more times going out the trail and back into town. For me When I got home I took the cover off of the gas tank vent and found that one of the vent lines had broken off of the plastic vent tank. So I JB welded it back in place and that took care of the venting fuel. So far its holding great. I also changed out a fuel filter that i did not think was very old but had lots of rust color in it when I dumped it out. Ive only driven it up and around Holy cross trail so far, but, it seems to be running just fine now.! ? ! Hope you still have your cruiser! I plan on keeping mine for ever.

 

[venpick]

Holy cr*p after i posted this I actually looked at your info and saw the crawlorado info. You are like famous and stuff ive seen youtube vidjas of a yellow crusier racing in the we rock races. Nice Cruiser man!