340 Fuelpump problems

[Belgium Cuda]

 Just rebuild my 340 Cuda engine and I am now ready for start up. I get 80 Psi oilpressure by cranking but doesn't get the fuelpump
 to deliver gasoline. Could I have put the carter fuelpump wrong towards the cam? Can it be air in the system? Any ideas would help please. 

[LAA66]

 Air in the line would not be the problem. I left a temporary cap on the fuel supply line once and had a similar problem. 

[Super Blue 72]

I would pull off the line just before the pump to see if gas is coming out.  If it is, then you know gas is getting to the pump and there is not air.  Air in the system shouldn't take too much time to work its way out.  When I replaced my gas tank I din't have to crank too long for the engine to fire up.

If there is gas getting to the pump, reconnect the line at the pump then disconnect the line at the carb from the pump, put that end in a container and then crank the engine.  If there is gas coming out to the carb, the issue is iin the carb.  If there is no gas coming out of the line, then the issue may be at the pump.   

[Belgium Cuda]

 If I would put my finger on the inlet side of the pump and crank, should I feel the pump "sucking" then? 

[Super Blue 72]

I would think so, but don't seal the inlet side completely with your finger.  It may damage the pump diaphram or your finger! 

[matt63]

Generally, by the time you pour a little gas into the carb and the engine tries to start once or twice the pump has started working.  If this is not the case I would check a few things out.

If this is a newly rebuilt engine with a flat tappet cam you really need to get it started quick with minimal cranking.  I would follow the advice below as far as splitting the line to the suction side of the pump and seeing if there is gas there.  If not I would try and siphon it and get the gas flowing to the pump.  If you can't do this then you definitely have a problem on the suction side.  Once you have gas at the suction you could loosen the line on the pump discharge and crank the engine a few times to see if it leaks.  If it doesn't then the pump or eccentric is faulty.  If everything is okay, I would fill the carb bowl with fuel manually (this is why electric pumps are nice) and see if fuel squirts from the carb when the throttle is opened.  If not then their is a problem with the carb. 

[Super Blue 72]

Another goofy thing that comes to mind is make sure all your clamps on the lines going to the pump are tight or else the pump will be sucking in air.  This happened to me many moons ago.... 

[dodge freak 2]

You need to make sure when installing the pump that the leveler is on top of the fuel pump cam. Its easy to just stick the pump in and not have the long pump drive on the fuel pump lobe. Sometimes you need to bump the motor over to bring the cam drive down-if it happen to be at the highest point its very hard to install the pump right. Take the pump off and when installing it again, go in with the long leveler pointed up as much as poss. You should feel the spring fighting you as you straighten the pump even with the cover.

Hard for me to explain but I have a huch thats it. I did it before when I did not know how the pump works.

[MEK-Dangerfield]

IF everything is correct in your system, pouring a little gas down your carb to get the engine almost started should do the trick. I replaced my solid fuel line from front to back. Just about the time the fuel in my fuel bowls was gone, the gas arrived from the tank.

This is a stupid question, but how did your pushrod for the fuel pump look before you shoved it up into the block? If the rod wasn't worn, you should of had to apply a little pressure to get the pump up snug enough to the block to bolt it in place.


  Mike

[Belgium Cuda]

 Many good advices, Thanks! matt63 makes me nervous since you advice me not to crank to much. I have a flat tappet cam and
 cranked a lot to get oilpressure  The pushrod was a little bit worn and it was some bending and pushing to get the pump in.
 I will then start from the tank and work my way to the carb and let you know my progress. hope my new cam will still be Ok. 

[dodge freak 2]

Pushrod for the fuel pump? I thought this was a 340. The pushrod are used on the big blocks I believe. Theres no fuel pushrod on the small blocks, unless you are talking about the long leveler or arm.

[matt63]

It's a little late now but you should use a hex priming rod and a drill to prelube a new engine.  I would add some break in lube to the oil as added insurance no matter what.  The stuff I use isn't readily available but there are other mfg's of this stuff.  I think Comp Cams offers it.  I'm sure there are some threads on this.

[Belgium Cuda]

 I did mean the leveler MEK-Dangerfield refered to. matt63, do you mean besides the camlube I putted on the camshaft when I installed it?

[Moparal]

Yes he does. And did you put it on the cam/distributor drive gears?  Did you make sure to tighten and loctite your fuel pump ecentric and cam bolt?

[Chryco Psycho]

It could be the wrong pump , a pin hole in the line with prevent fuel pumping as air is easier to move then fuel I would fill the carb with fuel before firing it