C1 Fuel Tank

[Terry D.]

Re: C1 Fuel Tank

Joe
You've got mail
Terry

[Joseph U.]

Re: C1 Fuel Tank

I checked cylinder #1 with a spark tester - in line - between spark plug wire and the plug.
I do not see fluid shooting into the carb when I pump the throttle, but car will start and run for a few seconds if I put gas directly into the carb.
Question is how to check the float or if carb is blocked.
Thanks for the help.
Joe

[Joseph U.]

Re: C1 Fuel Tank

???
No messages in my inbox.
Joe

[Joseph U.]

Re: C1 Fuel Tank

Spent a long time talking with Terry yesterday and we kind of narrowed the problem down to the carburators, and was going to have them rebuilt, but he asked if there was a filter at the inlet to the carb - and there is, so he suggested testing that first. I disconnected the line to the rear carb - and again checked for flow - no gas going to carb. I emptied the filter bowl again, cranked the engine - the bowl filled but no gas to pipes going to carbs. Took the bowl filter off and connected a line from fuel pump to rear carb - cranked - and started up - so something must be amiss with the fuel filter - which is fine, bought a new filter and will reassemble tomorrow. (old filter was folder paper, new filter is porus metal or stone). Can anyone come up with a reason why a problem with the fuel filter set-up would be intermittent?
Thanks,
Joe

[Mark E.]

Re: C1 Fuel Tank

Your post is a good reminder to check basic things, like a plugged filter.

You're a lucky guy if a $5 filter fixes the problem.

I can imagine a partially plugged filter will struggle to provide the needed fuel flow under all conditions. And when the carb suffers restricted fuel flow and/or pressure, fuel level in the bowl, and hence the air/fuel metering, is affected.

Also, with a mechanical fuel pump, pressure varies with engine speed and temperature. So maybe when the pump's pressure was on the low side, it wasn't enough to overcome the restriction from the dirty filter.

[Joseph U.]

Re: C1 Fuel Tank

The fuel filter appears to be the problem - but I still do not understand it. If I run a line directly from fuel pump to carbs - starts right up, if I put a new filter in the fuel filter and reinstall - will not start - again check with line without filter - starts - installed an inline filter and starts right up - but looks like the bubba fix that it is. I just don't understand it - that filter does not look that complicated - fuel goes in, thru the center hole in the filter cartridge into the bowl and then goes from the bowl thru the filter (either paper or bronze) and to the engine. So does the fuel pump push the fuel thru the cartridge or does the carb draw the fuel thru the filter. Thoughts?
Joe

[Mark E.]

Re: C1 Fuel Tank

First, the pump pushes fuel to the carb. The carb cannot draw or suck fuel into itself.

Are you using an extra, aftermarket filter? Or just the original filter? Or both? Sounds like both: "...fuel goes in, thru the center hole in the filter cartridge into the bowl and then goes from the bowl thru the filter (either paper or bronze) and to the engine..."

If using two, try only one (the one put there by GM). Two filters in series may create too great of a pressure drop.

[Joseph U.]

Re: C1 Fuel Tank

The filter assembly is an aftermarket bowl set-up to look original. Using only one filter - first filter was paper filter - that may be all "Shellacked" up from gas sitting in there over the summer. The new filter is again an aftermarket bronze filter. But only using one at a time. The "in line" filter now on the car is a stand alone filter, generic, no bowl, just an in-line gas filter.
Thanks for your thoughts. I can tell you that the after-market bronze filter seems quite small to me, but the bowl does fill up with gas, which is going thru the center hole in the filter, but does not get to the carbs (thus must not be passing thru the "filtering" part of the filter.
thanks,
Joe

[Terry D.]

Re: C1 Fuel Tank

Joe
Have you tried the glass bowl with no filter in it?. Sounds to me like the exit passage of the bowl is plugged. Tried blowing air thru it or a thin wire.

[Joseph U.]

Re: C1 Fuel Tank

I have not done that - but the line is clear - I can easily blow thru the filter.
joe

[Lucas V.]

Re: C1 Fuel Tank

I had a passage on a fuel filter that was collapsing on the inside, another that created its own vacuum lock for some odd reason, which stopped gas flow - another that had a little ball of tar wedged in the line, just enough to stop flow at times ( that one was on a plane - it caused "unable to reproduce" maintenance gripes until I had to declare an emergency when fuel stopped flowing from one tank. The mechanics finally cut everything open to find the problem.