Bad Fuel Pump?
#1
Bad Fuel Pump?
I just tried firing up my 1950 V8 and the car just cranks, no sign of starting. The fuel bowl attached to the fuel pump was full. I emptied the bowl, cleaned it out and replaced it. I tried cranking the engine and do not see any fuel in the bowl. Does this mean the fuel pump is bad, or do I need to pre-fill the bowl to get vacuum going?
#2
Take off the line coming from the fuel pump, get something to catch the fuel, and have somebody crank on it. If it pulls fuel from the tank then the pump isn't bad. After that I'd put a little bit of fuel in the bowl and see if it won't fire. If it still won't take that little bit of fuel then you know it's an issue with the vacuum.
#3
Make certain there is no leak at the glass bowl. They are notorious for leaking and the pump, if working, will suck air before it sucks gas. If the pump is working and not drawing air, you'll see fuel fill the bowl. Also, check that flexible suction line that feeds the pump, it looks old and frayed. Could very well be your problem. These pumps work by creating a vacuum and any air leak will prevent the vacuum being created.
#4
Note that the top of the gas tank is only about 8" lower than the inlet to the pump. I'd bet Ray is correct that you are losing suction due to that inlet hose. Even a pump in poor condition will suck gas up a foot or so. But if your fuel lines are plugged with sediment, no pump will draw thru that.
#5
#6
The rod doesn't move a huge amount, are you saying it doesn't move at all? Can you put a screwdriver on the rod and watch for movement? If it isn't moving about 1/4" - 3/8", pull all the plugs and crank the engine while watching the valves thru the spark plug hole. If the valves aren't moving, your cam timing gear is likely broken.
#7
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#10
Are you sure the pushrod is down on the cam? It's really pretty unusual for a flathead to wear out the eccentric but it happens... Welcome to the world of trouble-free electric fuel pumps! Unless you want to pull the engine, remove both heads, all the valves and replace the cam... I know what my choice would be!
#11
#13
Edit: I share Ray's skepticism that there is NO movement, but if it isn't obvious then it isn't enough.
There is a small hole in the bushing the pushrod rides in, that lets oil onto the eccentric. The pushrod is a really sloppy fit in the bushing. It's a good idea to cut the pushrod off level with or just below the opening in the intake manifold, and put a flat plate over the opening. I made one out of 1/4" aluminium, but various place sell fancy covers too. The pushrod being in the bushing will keep oil from spraying up onto the bottom of the intake manifold.
Are you still 6v? If so I'd recommend a Carter pump with a Holley regulator set to 2 psi. P/N 12-804.
There is a small hole in the bushing the pushrod rides in, that lets oil onto the eccentric. The pushrod is a really sloppy fit in the bushing. It's a good idea to cut the pushrod off level with or just below the opening in the intake manifold, and put a flat plate over the opening. I made one out of 1/4" aluminium, but various place sell fancy covers too. The pushrod being in the bushing will keep oil from spraying up onto the bottom of the intake manifold.
Are you still 6v? If so I'd recommend a Carter pump with a Holley regulator set to 2 psi. P/N 12-804.
#14
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