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What's up with my fuel situation...

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J

Justin Bowen

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I had the motor running. Every time I hit the starter it would crank and run.. idled rough usually, wouldn't stay running for more than 30 seconds unless I gave it gas. I was happy with that as a starting point, then this....

about a week ago I was running the motor to test a few things and it died and wouldn't start back up. I figured I ran it out of gas, which is very possible since I only put about a gallon in the tank.

Now, a week later, I add 2 gallons and the thing just won't start. I pulled the fuel line at the carb and it does move some fuel, but in spurts, not a smooth flow. I seem to recall it was like this before though, when it ran.

Any ideas? Could there be air in the line? If so, how do I fix that?

Thanks, you guys have been a big help so far...

Justin
 
possible causes
is the tank venting properly?
torn diaphram in the fuel pump
clogged or deteriorating fuel lines
is there enough fuel in the tank for the pick-up?
 
Hello Justin,
mechanical or electrical (S.U. pumps) tend to pump in spurts due to their construction. (Diaphragm). If you are getting some fuel then the engine should fire; you will need to look at something else. Easy way to see if it is carburettor or ignition (don't forget that adequate compression is also required)is to put some fuel in a squeezy bottle or similar and squirt it into the carburettor intake and crank the engine. If it still won't fire it's not a fuel problem. From the sound of it you need to go through all the tune up settings though.

Alec
thirsty.gif
 
First, & I'm assuming you still have your original Lucas fuel pump...is the pump pumping? When you turn on the ignition do you hear the fuel pump tick-tick-tick? If you don't, rebuild your pump. Simple job much like repointing a distributor.

Second, fuel leaving the fuel lines at the carbs in spurts tells me you have problems moving fule - either the pump isn't dsoing its job or you've got an air leak somewhere...see, the tic-tic-tic of the Lucas fuel pump is it pumping up (i.e., pressurizing) the system...once the system is pressurized, the fuel pump operates to maintain that pressurization....that you're pumping gas in spurts tells me there's a problem in the lines, pump, or tank...focus there!
 
Justin,
I tend to agree with alec. I have never seen a diaphragm type pump that didn't pulse when pumping against zero pressure (open fuel line)

A simple check is to let the open fuel line dump into a can & let the pump run for one minute. If all is ok, there should be about one pint, or more, of fuel in the can. This is equivalent to 7.5 gallons per hour & somewhere around the pump rated capacity.
D
 
Mine has a continuos flow varing with the pump pulse. So if you are saying pulsing meaning fuel stops or almost stops between pulses then I'd say there was a problem with the pump or the things Kimberly refered to. Also you should have around 1 1/2 to 2 lbs of pressure from the pump. So, if you have this, I would look somewhere else.
Also, if you checked it after the fuel filter, you might check it again before the filter. Might be a clogged filter.
Next, maybe Piman's suggestion and if it still doesn't fire go to the ignition.
Bob

[ 10-22-2003: Message edited by: mrbassman ]</p>
 
Against an open fuel line there will be a 'minute' pulse only because there's no pressure buildup...however, if you're noticing a rather pronounced pulse, there's a problem...IMHO
 
Hello all,
I don't think I made myself too clear. If there is fuel there and it won't fire, then it is not the pump that is at fault (that is not the same thing as saying there is no problem with the fuel supply). By the sound of it there should be enough fuel to fill the float chamber which is enough to at least get the engine to fire. The next stage is to eliminate what is working and what is not and dumping fuel into the carburettor intake is the quickest way I know.

Alec
thirsty.gif
 
You're still confusing me...does it run when fuel is injected into the carb? Its irrevalent whether or not the fuel comes from the gas line or a can - does it run then? If so, the problem is fuel related; if not, the problem is ignition related.
 
I think you confused yourself
smile.gif
Alec was just clearing up what he said in an earlier post.

So I guess what I'll do tonight is spray some gas directly into the carbs. If it DOES start, I have a fuel supply problem. If it DOESN'T start, then I definitely do not have a fuel problem and I should look at ignition, etc.

Compression looked okay when I tested it last week. Also I do believe there is enough fuel in the float chambers to start the car, so I'm pretty confident at this point that it's not a fuel issue. I just thought it was weird that the only thing I saw change was I ran it out of fuel, then it wouldn't start later.

I'll test tonight and post the results. Thanks!

Justin
 
Justin,
I'm not trying to preach but DO be careful. I saw a guy horribly burned when he poured gas into a carb, had someone try the starter, car backfired & blew burning gas all over him. Don't be in line with the carbs when you hit the starter.
D
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Dave Russell:
Justin,
I'm not trying to preach but DO be careful. I saw a guy horribly burned when he poured gas into a carb, had someone try the starter, car backfired & blew burning gas all over him. Don't be in line with the carbs when you hit the starter.
D<hr></blockquote>

Got it. Thanks
smile.gif
 
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