fuel pump question/problem....

69monaco

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The imperial i bought lately doesn,t run on his own.....
I saw they put a electric fuel pump under the car but that was also connected to the normal fuel pump?????!!!!!

I didn,t hear the elec-fuel pump so i made it original , see of it would run........
It didn,t........

The fuel line is good , there,s gas going to the man-pump..........
but no gas is coming out on the carb going side.

I took the pump of and i saw the pushrod was 5mm shorter than it has to be...
I put another one in it but still no gas........

If i put the level in with my hands it sounds/feels good like a new one ....heavy...
and yes it squirts gas from one to the other side......
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Could it still be the pump / do i need another/new one ........
Could it be a worn nock on the cam..........?( never heard of that but...???).
 
Have you checked the fuel line from the pump to the carb for blockages? How is the fuel filter looking?
 
I don't really have an answer for you but I can tell you my experience. We bought a '68 300 with an electric fuel pump installed the same way as yours. The seller told us the fuel pump on the car was bad but there was a good one in the trunk. We removed the electric pump and installed the new mechanical pump, but it didn't just take right off. It was like it had to be primed or something. It took a bit of effort to get it pumping, but once it started we've had no problems. Just make sure you have it hooked up right, have no kinks in the hoses. I think we stuck the input and output hoses in quart jars of gas and cranked the engine to confirm it was pumping.
 
The imperial i bought lately doesn,t run on his own.....
I saw they put a electric fuel pump under the car but that was also connected to the normal fuel pump?????!!!!!

I didn,t hear the elec-fuel pump so i made it original , see of it would run........
It didn,t........

The fuel line is good , there,s gas going to the man-pump..........
but no gas is coming out on the carb going side.

I took the pump of and i saw the pushrod was 5mm shorter than it has to be...
I put another one in it but still no gas........

If i put the level in with my hands it sounds/feels good like a new one ....heavy...
and yes it squirts gas from one to the other side......
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Could it still be the pump / do i need another/new one ........
Could it be a worn nock on the cam..........?( never heard of that but...???).

A good pump should have no trouble pulling gas from the tank as long as the line is intact and not leaking. It does take a little cranking to get it going if everything is dry, but it does the job.

To test, you disconnect the gas line after the pump and disconnect the coil wire (so engine does not fire). You hook a hose from the gas line to a bottle or can and crank the engine over. There should be a good stream of gas squirting into the bottle. If not, the pump is bad.

Since someone has already put an electric pump in the line, that tells me that there was some problems with the pump and you've discovered the rod was short. That doesn't say that the pump wasn't bad too.

5mm, (or ~3/16 in this part of the world) is a lot of wear though... I think the rod is usually softer so it takes the beating, and I can't discount the cam lobe taking some wear too, I'd be thinking that there would be other problems with the cam with bad lifters or lobes.

Was this car running when you bought it?
 
Use a suction gun on the line, does it prime? If not, plugged sock, or holes somewhere in the line, possibly in sender
 
With tank half full or so, and the line charged from cranking the motor some, take line off feeding the pump, should be a steady gravity flow that would eventually empty tank. No flow, then sediment/rust in tank plugging pickup screen, or perhaps detreated/collapsed rubber rubber hose sections at line connections.
 
Was this car running when you bought it?[/QUOTE]

3 years ago it did run , the seller drove it in his barn and didn,t do nothing with it since...
He tried to drive it out not long ago but than it only run if he puts gas in the carb.....
( that,s what HE told me )....

I will try another ( new )mech-pump and if that not works i will go for a new electric one.

Thanks for the other answers , i.ll let you know......:thumbsup:
 
3 years is a long time for gas to be sitting, especially in an old tank. Before throwing money at a new electric pump pull the sending unit and look at the pick up. If the sock is gunked up it would be wise to drop the tank and have it cleaned. Then you can work your way forward, replacing any rubber fuel line on your way to the mechanical fuel pump. Today’s fuel is brutal on old rubber lines & doesn’t store well over long periods of time. I have owned quite a few of these cars over the last 40 years and never once had to put an electric fuel pump on one because the mechanical one couldn’t cut it. Good luck.
 
3 years ago it did run , the seller drove it in his barn and didn,t do nothing with it since...
He tried to drive it out not long ago but than it only run if he puts gas in the carb.....
( that,s what HE told me )....

I will try another ( new )mech-pump and if that not works i will go for a new electric one.

Thanks for the other answers , i.ll let you know......:thumbsup:

There's a lot going on here.

Sitting 3 years isn't good, but I would be a little surprised if it gummed everything up. But with a sketchy history, you really need to check things out.

First, easy stuff.... remove the rubber hoses and toss them. You should change them as part of getting this car road worthy anyway... I'd try to blow through the steel line just to be sure. Pull the sender/pickup and check the sock. Again, I would be a little surprised if sitting for 3 years completely gummed it up, but it's an unknown at this point. Take a look in the tank while it's apart.

Now you have new rubber and a good idea about the shape of the rest of the fuel system.

But, before I would do any of that, I think the thing to do is a squirt or two of gas (or some starting fluid) down the carb and see if it fires up. If it does and dies, try it again... That will tell you if the fuel system is your problem.
 
Similar problem on one of my cars that sat for ~3 years. Fuel thru the pump, but nothing at the carb. Acting like an air lock. Applied suction to get gas up the hard line to the carb, reattached the line to the carb, and it fired right up. No problem since . . .
 
Have you checked with the new mechanical pump and rod that the pump is or isn't pumping anything if the line to the carb is disconnected? Didn't notice that from your previous post.

I am just guessing here but you might also have a stuck needle in the carb in addition of the other already found problems
 
Okay .....the imperial runs ; it was the pump.
They sounds both the same pushing between my hands but the old was not doing the job.
It runs on the old gas ( clean , not rusty )but it,s running like a diesel ...:lol: , oh and the timing was 5 degrees before tdc..............probably it was in the hands of a GM mechanic..

:thankyou:.
 
Okay .....the imperial runs ; it was the pump.
They sounds both the same pushing between my hands but the old was not doing the job.
It runs on the old gas ( clean , not rusty )but it,s running like a diesel ...:lol: , oh and the timing was 5 degrees before tdc..............probably it was in the hands of a GM mechanic..

:thankyou:.
Get the old gas out... and replace it.

Since gas is expensive, especially over there, use it a gallon or two at a time in the daily drivers to get rid of it if you are cheap like me.
 
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