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Car will not re-start after a drive - Help.

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I think doc's right...if the system fully pressurized, the pump would stop ticking...I think we're back to a leaky diaphragm or the flex line leaving the pump....why it doesn't always do it is still a mystery though.

If no fuel is getting to the floats, its not a case of too much fuel which is the reason for a regulator.

As a first step, I'd pull the hose off the pump, turn it on, & see if an adequate flow of gas is leaving the pump....if it isn't, we know its internal to the tank or pump....if it is, we know its in the hose/hard line.
 
Vince - You don't say (or I missed) what fuel pump you have in the car. If it is a SU fuel pump, there is no need for a pressure regulator, but if you have an after market pump you may need one, depending on the output pressure of the pump. Also if you have an after market pump, that could be the reason that the pump doesn't stop running. It is an outside possibility that the fuel is boiling in the fuel line, which would cause a bubble in the line or the filter and the pump is unable to pump past the bubble, but I would be surprised if that were happening - one of the advantages of the pump mounted in the back of the car, the fuel from the pump forward is under pressure whch will prevent that sort of thing from happening. I am with Tony, remove the fuel line from the carb and direct it into a can or jar and turn the ignition on. A standard SU fuel pump should pump 2 pints per minute - anything less and you either have a clog somewhere or the pump is failing (see my Fuel Delivery Troubleshooting Guide in the Library). An air leak on the inlet side of the pump is a posibility that the above test will show if there are bubbles in the fuel being pumped. If this is the case, I would expect a hole in the line from the tank to the pump or a gasket on the inet air bottle leaking. A rptured or leaking diaphragm happens so rarely that I haven't seen a single case in the 30 years I have been working on the pumps.

Something you said that raise an eyebrow when I read it. You said "Starts without the choke and runs like a champ. As soon as it gets up to temp & I turn it off It won't start. Acttually right bec=fore I get home it starts acting really strange and sputters like it wants to stall." Is there a chance that you have the carburetors set way too rich? If you are set rich enough to start on a cold engine without the choke, it may be rich enough to cause a running problem whenit is hot.
Cheers,
 
David_DuBois said:
.... Acttually right bec=fore I get home it starts acting really strange and sputters like it wants to stall." Is there a chance that you have the carburetors set way too rich? If you are set rich enough to start on a cold engine without the choke, it may be rich enough to cause a running problem whenit is hot.
Cheers,
Click to expand...

Explain why running rich wold cause hard starting after hot & how I do not see any gas at the back of the car if there is a leak?

Cooindidentally I had changed my side cover gaskets on the 19th. Befoer I put the carbs in I decided to reset them and someone recommended .120 thou which should have been according to them 12 flats. In ordet to get the .120 I had to go 16 flats. Yes I am running very rich and it is on the agenda for this morning.
 
I still need this question answered "Explain why running rich wold cause hard starting after hot & how I do not see any gas at the back of the car if there is a leak?" but here is the latest.

I leaned out the carbs 6 flats changed over to NGK plugs gapped .025. The old ones were sooty as a result of running rich. Put in ignition and heard fuel pump only tick a few times. Car started right up & ran perfectly. I pulled it out of the Garage and let it run for about 3-4 minutes. It slowly started to reduce RPM's slowly, slowly, slowly until it was about to stall so I turned it off. Tunred the key back on and the fuel pump is ticking away as if I was out of gas. Mind you the temp was now 190Âş on the guage which is why I shut it down. Based on this I think it is an under the hood problem but what???? I'm miffed. Up till this passed week, it never did this.
 
Oh and Dave, It's an SU Pump back there. When I got the car a year and a half ago, It was not working. All I did was take it out, clean the points, reasembled & reinstalled. Has worked like a champ ever since.
 
Check the hoses connecting the fuel filter to the lines.

Maybe the prob is where you wiggle things, check what you are moveing and remove and replace from your stash.
 
A little more info.

I started the car let It run & it died.

It cooled for about a half hour temp down to 140Âş. Key in only & the pumps is ticking away. Tried to start & it was tough but I caught it just as it was firing and was able to fully start & get back up the driveway. I turned the idle up a little and it started and ran fine without cutting out. I let it run and it seems to be idling fine & running fine. I let it run up to above 190Âş and shut it off. I let it sit a few inutes & it started and ran fine.

Could the problem have been this. My idle was too low and when it finally reached full operating temperature was idling so low it caused fuel starvation problems & wanted to stall? Could it cause a bubble to form because the pump it pumping too much gas forward with nowhere to put it because of the low idle?

Am I grasping at straws?
 
Idle wouldn't cause: "I get out and look at the glass inline filter - No gas"....nor would it cause the fuel pump to never stop ticking.
 
Pump always ticks. It either ticks & stops because of the bowls are full or it ticks as if there isn't any gas in the car. I going to go test to see what my flow is like.
 
Vince - I don't really have an explanation regarding the rich running, but have heard of that situation before and though it might be worth checking. You can have an air leak between the tank and the pump because you essentially have a vacuum on the inlet side of the pump when it is operating (I measure the inlet vacuum of the pumps that I restore and it runs anywhere from 3 inHg to 7 inHg). This can suck air into the system but not leak fuel when the pump is not running because there is never any pressure in the line.

I have seen the problem of the idle changing as the engine heats up, but not to the extreme that you are describing. One of the causes of this situation is worn throttle shafts or bushings in the carburetors While this could explain the change in idle speed, it does not explain the constant running of the pump. I really think that a check of the pump's operation and volume of fuel being pumped is in order. You may actually have two separate problems, one being the idle change at operating temperature and the other being a fuel pump problem combining to make your life really difficult.

Cheers,
 
Pump should stop ticking when the bowls are full.
 
Which it does and has done since I got it. It's just now when it gets warm, It does not pull gass out of the tank.
 
Have you tried running it without the inline filter? I've seen filters do some odd stuff (especially if they are installed backwards) and it would be an easy thing to eliminate without hurting the car.

Adam
 
Running rich should not prevent the car from starting. If anything it would help with vapor lock. My TC ran super rich due to worn guides for some time. All it meant was that I never needed choke, and it was a little smelly to those following. It will help cool the engine also.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I pulled it out of the Garage and let it run for about 3-4 minutes. It slowly started to reduce RPM's slowly, slowly, slowly until it was about to stall so I turned it off. Tunred the key back on and the fuel pump is ticking away as if I was out of gas. Mind you the temp was now 190Âş on the guage which is why I shut it down.[/QUOTE]
Did you run it with the bonnet open? If not, try that. You might also put a fan across the engine bay. Make sure the fuel lines and pump aren't getting excess heat from anything. It really sounds like vapor lock. That's exactly what my TC would sometimes do in very hot weather when moving slowly, or after parking for a while with the bonnet closed. But it would have to be pretty hot.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]It's just now when it gets warm, It does not pull gass out of the tank. [/QUOTE]
somewhere there's a leak that causes the fuel system to lose its pressurization...
 
Exactly Steve.

I ran it with the bonnet closed to simulate the heat it generated from driving.

Losing pressure makes sense but just now I put her away for the night had not started it since 1:30 pm. Turned the key & it ticked maybe once or twice, to full pressure & then started right up. I bet you if I let it warm up and turned it off the pump would be ticking away but not filling the filter.

So if I had an inlet hose leak, would there be any signs of a gas leak? My guess is no. Does that mean it sucks in extra air, and how is it affected by heat when it is hot under the bonnet, which is miles away from the pump, and gives me trouble later on.

If vapor lock is suspect, how do you get rid of it and why all of a sudden. I've driven in much hotter weather with no problems.
 
I think I said before, Pump pump pump.
 
I've had inlet hose leaks that dripped no fuel. If the hose is old then it should be replaced regardless of whether or not it is causing this problem.

If it's vapor lock, you need to do something to cool wherever the fuel is boiling. Usually this is in the pump or the float bowls.

1. A heat shield with insulation can be installed under the carbs.

2. A secondary pump can be installed in the rear of the car, or at the pipe union along the side rails. This will do all the work and the SU will become for show only, or if the secondary pump fails the SU will take over.

3. Vent the engine bay better or install an electric fan.

I can't think of a reason why it would start all of the sudden, but a change in weather can certainly make a difference.
 
Yesterday got a little busy so I need to crawl under & inspect the pump and lines.

I know I replaced all the rubber that was under there.

Heat shield with insullation is brand new & installed.

Seconday pump is not a bad idea. Show & no go is not cool plus who looks at the pump under a GT.

Vent the engine bay, how? Not keen on installing a fan.

Weather has changed but it been cooler this summer more than I can ever remember.
 
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