TR2/3/3A Tr-3a fuel delivery

[midnight]

For some reason my carb's are starving for fuel - I watch my fuel filter (just in front of the carb's) and eventually it will run dry - I have checked all of my lines - no issues, I have tested the fuel pump, once again no issues - if I loosen the sediment bowl, then fuel flow to the fuel pump is excellent - It acts like I almost need a vent at the pump - I have never had such a problem - the car has ran fine until just recently - any ideas - midnight

 

[Geo Hahn]

The filter you describe sounds like an aftermarket clear one -- those do not typically get full when the engine is running though it should not be completely dry.

I would remove the tops from the fuel bowls and see if there is fuel in there.

If there is not - then the problem in in the pump, lines or tank. You say you tested the pump, does that mean you disconnected the line to the carbs and observed fuel pumping out?

If there is fuel in the bowls then likely the valve is stuck. By chance do you have Grose Jet valves? Those are prone to getting glued shut when the engine sits for awhile (as Randall says, 'I have experimented with that'.

Since you get fuel flow to the bowl it would seem that you are not out of gas.

 

[CJD]

Recently, like when the temp in Reno went over 110 deg? If it only happens with the car warm, I'd suspect vapor lock.

 

[midnight]

I had the problem this afternoon - I disconnected the fuel line at the carb. and run the pump mannualy - got fuel - checked to see if needles were stuck - all OK - I finally got it going and made it home - when i popped the hood there was barrly a trickle of fuel fllowing in to the filter - the manual activation of the pump produced nothing -

 

[CJD]

That sounds more like an obstruction in the line between the tank and pump.

 

[Don Elliott]

Remove that filter and splice in a short bit of hose with clamps. Test it with no filter. I have over 195,000 miles on my 1958 TR3A and never had a problem with no filter there.

 

[TR3TR6]

Did you by any chance add fuel to your tank from the pump. I had the same issue on a Spitfire many years ago. What happened was when I filled the tank it either broke some particles loose in the tank or some came in from the pump. I ended up having to remove the tank and flush it out. While I was driving, the particles would settle to the bottom of the tank and block the fuel line. They were too big to go through the line.

 

[PDP-3A]

If you have never rebuilt your fuel pump, you may have the original rubber diaphragms which have a tendency to get pin holes due to the ethanol additives. The new replacement diaphragms are neoprene and hence are not subject to the degradation by the alcohol. I encountered this problem last summer. The car would start, I'd be able to drive for about a mile and then the carbs would starve and the motor would die. After 3-5 minutes I'd be able to start it again and drive another mile or so. When I rebuilt the fuel pump and held the old diaphragms up to the light I could see the small cracks/pin holes - just a thought


Peter


'60 TR3A

 

[midnight]

I have no obstruction in any of my fuel lines - including a new filter (upon inspection, I find no issues with the filter I had been running) - I have also rebuilt an original fuel pump utilizing the Roadster Factor's kit - this pump replaced the Moss Moter's pump I had been running - both pumps have not given me problems - however, I have no other choice but to assume they both have a problem (strang!!!!) soooo, I am in the process of installing an electric pump - midnight

 

[sp53]

The filter is probably plugged with floating crap or the same in the tank.