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Air in the fuel line?

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NutmegCT

NutmegCT

Great Pumpkin
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For the first time in ... quite a while, I removed the fuel sediment glass at the TR3 fuel pump. As the fuel cut-off valve was removed many years ago for some reason, the fuel in the lines drained out when the glass was removed.

Poured out the crud, then put the glass back in place.

Ever since then (Friday), the engine starts quickly but then just stops in about five seconds. Regardless of choke position.

Engine doesn't cough or run rough - it just dies, as if the ignition were turned off.

I see gas entering the clear plastic fuel filter (just before the carbs) when I pump the priming handle.

Does this sound like I have air in the fuel line and/or pump? If so, how can I "purge" the line?

Thanks.
Tom
 
If you've tried that several times, then my guess is that there is something else going on. Usually if it is sucking fuel at all, the pump will quickly clear any air out of the lines (by blowing it out through the float valves).
 
On occasions when I had the glass bowl off the pump and didn't get a good seal when I refit it I got a fuel leak there -- but perhaps if the tank is low enough the pump would suck air there?

Is the glass bowl full of fuel?
 
any leaky rubber hoses between the pump and the tank? I had one leaky connector and the pump sucked in air instead of gas.
 
Thanks for the suggestions.

The reason I decided to empty the sediment bowl, was that there was gasoline on the top of the sediment bowl fitting, and on top of fuel pump. When I started wiping off the gas (it was *old* - not fresh), I noticed the crud in the sediment bowl.

I removed the bowl, emptied the gas, then reattached the bowl. That was when I wondered where that "spilled" fuel was coming from.

There's a rubber fuel hose coming up from the steel line under the car. The hose runs up the driver side inside fender. That hose is attached to the steel line at the sediment bowl, and held by hose clamp.

The hose clamp was actually slightly loose, and there was fuel on the steel pipe at the hose clamp.

So I tightened the hose clamp, cleaned up any spilled fuel, wiped off all the formerly "wet" fittings, and started the engine. Let it run about ten seconds, then shut it off to see if more fuel was leaking.

All dry - so the loose clamp was evidently the cause of the fuel on the top of the fuel pump. I also checked the top screws on the fuel pump, and other fittings in the area, and all were tight.

So now the whole area is dry and clean ... but the engine won't keep running.

And the bowl is full of fuel.

Tom
 
well its alway occured to me that when you do a task on your car to fix something, when nothing was wrong and you have an issue after the repair, then go back over your repair step by step and you will find the problem thats caused your new issue

Hondo
 
OK - which one of you guys sneaked over here and fixed it?

I cranked it up and jumped up to watch the fuel bowl when the engine died.

The engine didn't die.

I waited for over five minutes, and it idled nice and smooth. Shut off, restart, no problemo.

I didn't change anything - was it long distance healing? unique planetary alignment? The BCF Mystery Fixer?

Only the Shadow knows!

Yippee!

Tom
 
It will run more than a few seconds on the float bowls themselves. Shutting down like the key is off is probably just that, loss of ignition. Beware, it will probably return when you least expect it!. Check the wires at the coil and distributor for tightness. Something may have loosened up or moved while messing with the fuel pump.
 
bnw said:
It will run more than a few seconds on the float bowls themselves. Shutting down like the key is off is probably just that, loss of ignition. Beware, it will probably return when you least expect it!. Check the wires at the coil and distributor for tightness. Something may have loosened up or moved while messing with the fuel pump.
Click to expand...

Thanks. One possibility: when the engine was in its "quick die" mode last week, I noticed the coil was really hot (too hot to touch) even if the ignition had been on only a few seconds and the engine hadn't even run more than a few seconds. The weather was HOT at the time.

Is that indicating a failing coil?

Tom
 
Based on the circumstances that you've described as to how long the car ran, that is not a good sign Tom. I'd get another coil and try swapping them out to see what happens.
 
NutmegCT said:
One possibility: when the engine was in its "quick die" mode last week, I noticed the coil was really hot (too hot to touch) even if the ignition had been on only a few seconds and the engine hadn't even run more than a few seconds. The weather was HOT at the time.

Is that indicating a failing coil?
Click to expand...

Sure sounds like it.
 
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