Chino California help

[Flynt]

I doubt the line's rate of expansion will vary that much from cold to hot...

you'd be amazed...  You've seen where 110 degrees in Kansas produces stunt ramps in the freeway?  Rails spring and bridges buckle all due to the cumulative stress of micron per cm rates of thermal expansion in solids.  Solids define the term incompressible, so forces build quickly and pinching off your gas would be a non issue.

I bet if you look it up fuel line (what are you using) will be hundredths per degree, so you'd get 1/8-1/4" or more expansion per foot when hot.  If your position cold is marginal, fix it and try again.

Frank

[FJmonkey]

you'd be amazed...  You've seen where 110 degrees in Kansas produces stunt ramps in the freeway?  Rails spring and bridges buckle all due to the cumulative stress of micron per cm rates of thermal expansion in solids.  Solids define the term incompressible, so forces build quickly and pinching off your gas would be a non issue.

I bet if you look it up fuel line (what are you using) will be hundredths per degree, so you'd get 1/8-1/4" or more expansion per foot when hot.  If your position cold is marginal, fix it and try again.

Frank

Ok I will bite, why now? This opens a big Ol can O' worms, I have not altered my fuel line routing in years... Maybe the fact that it is original as far as I know... Us old fucks change in ways we really don't want to know.....

[Flynt]

Ok I will bite, why now?

Maybe the lines are naturally swelling over time due to fuel exposure and they've reached the point of needing replacement.  How old are they?

Frank

[Flynt]

oops...  caught in do loop.

[FJmonkey]

Nevermind...

Frank

Frank, why are you counting? Does Marsh give prizes???

[Flynt]

Frank, why are you counting? Does Marsh give prizes???

Loco Monkey???   

[Flynt]

Loco Monkey!!!

how old are your fuel lines anyway?

[FJmonkey]

how old are your fuel lines anyway?

As posted, OEM I think

"Maybe the fact that it is original as far as I know... Us old fucks change in ways we really don't want to know....."

[Flynt]

As posted, OEM I think

these are fuel lines...  install new now and keep them in good shape.  you may need to change every few years when they get hard and crack.

this may not be your problem, but you should do it ASAP anyway.

Frank

[FJmonkey]

As posted, OEM I think

these are fuel lines...  install new now and keep them in good shape.  you may need to change every few years when they get hard and crack.

this may not be your problem, but you should do it ASAP anyway.

Frank

Good idea, Email already sent to Randy for a new one. Thanks...

[Pat Conlon]

A partially pinched fuel line could be the explanation as why you lose fuel pressure when the head pressure is lower ( low fuel level in the tank)
As long as the single fuel line leaving the petcock runs "under" the 2 branch lines, you're good there.
It is counter intuitive unless you can see how low the petcock outlet is positioned when the fuel tank is bolted down. If that single fuel line is run "over" the two branch lines you 'will' have problems, guaranteed.

[Marsh White]

I am leaning towards the petcock as the source of intermittent failure. A pinched fuel line or clogged filter are constant conditions. Filters don't unclog them selves then clog up again.

+ 1 on your petcock being the problem.  FYI: I was not referring to your fuel filter being clogged.  The problem I had was air getting trapped in the filter and creating a vacuum and not letting enough fuel flow.  It was very annoying and intermittent - AND this was on my 89 FJ WITH a fuel pump trying to suck the fuel out of the filter.

[FJmonkey]

Thanks to Randy at RPM I will have a new 84/85 petcock (with prime and no electronic reserve) today or tomorrow. I will get it installed, make sure the lines are routed properly, carb vent lines are open and not clogged or pinched and Bob's my uncle. Sounds wrong when I put it in the first person.... Now my FJ will be an 84'/86'/88'/92' model.

[FJmonkey]

The jury is nearly out on this one. But I have made an important discovery and feel that the problem is solved.

First, thank you all that offered solutions or opinions to help solve my problem. To those of you that offered cheap shots at my expense while I was down and out and in dire straights, thank you as well for cheering me up. For those of you that did not take cheap shots then Bugger off and thank you anyway. 

Randy at RPM delivered my new petcock, not in person but quickly and in time. Once off the tank I checked the old one by sucking on it. Not having ever sucked on one I did not know what was good or bad. I sucked on the new one and found that there was a difference. While sucking on the old one I needed to keep sucking, it was (as I now know) leaking. The new one had distinct click as the diaphragm opened the valve that allows fuel through. It did not need a constant supply of suction to resupply the loss.   

This is why my problem was almost intermittent and tough to diagnose. So to put it bluntly, suck on your petcock, does it need constant sucking? If yes then replace it or repair it.

Thank you all again for.....something..er...or another...Kookalooo

[1tinindian]

Monkey boy, you're such a petcock sucker!

Party on!