[speedfreek]

Well I've been having problems with fuel starvation. I thought it was my mech pump at first and bought a new one but did the same thing. I then installed an electric pump and bypassed the mech pump. Today i drove it to work in the morning and it ran great. But on the way home in 100* weather the carb ran out of fuel again. I limped it home, popped the hood and looked at the clear plastic fuel filter with it running. I saw many bubbles continuously in it. I grabbed my temp gun and shot the filter, 3/8 rubber line and the dual feed line at the carb. They all were 155*. My bottom radiator hose was reading 170* and is about 1/2'' away from the filter.

Do yall think it is boiling before the carb? I've never seen bubbles this much in the filter. Almost like the pump was sucking air? Any recommendations?

[Blown69RS]

I'm running an electric pump mounted near 3" exhaust on the rear frame rail. Running -8AN supply line, bypass regulator set approx. 5.5psi, -8AN return line to a 20 gallon aluminum fuel cell.

Last weekend, outside temp at 87, at the end of a 70 mile drive, and approx. 8 gallons remaining in the cell ---- using a thermocouple hooked into my IR gun and submerged into the fuel, the remaining fuel inside my cell was running 104.9 I only know that because I happened to be chasing my tail on a pressure related issue.

A tech at Aeromotive had just told me last week that the danger point he'd be concerned about cavitation would be approx. 140.

Not sure about actual temperatures up near the carbs like you're asking.... I'd think some of your readings would almost have to be influenced by radiant engine heat, and might not necessarily be the same temp as the liquid itself. With bubbles in the site glass though, I'd guess you're at least close to boiling the fuel. Just my 2 cents, by far not an expert.

Good Luck.

[Nashville Beth]

Can a gas cap not venting cause this ? Just a thought.

[Everett#2390]

It's called vaporization. The temps you are reading, I believe, are surface temps of the items measured, not necessarily of the fuel itself. Higher ambient temps, higher underhood temps.

With the elec pump, run a pint or so into a can and measure the fuel with a thermocouple submerged to read the net temp after the can is heated up by the fuel. Physics, cooler items will absorb the heat.

A couple fixes would be running a smaller return line always having a cooler flow and/or wrap the fuel line with insulation, or through a cool can.

Or drive the car at night, lower temps. JMT's