Alright so last night my bump did not really want to start and after a few pumps she fired but ran really slow and clumpy, I had just drover her hard earlier so I thought maybe she was tired. This morning I could not get her to fire. starting fluid made no difference but a sputter.
after jumping my truck and some more starting fluid she kept starting and dying. After plenty of choice words at 6am, she started but with my foot on the floor she just idled extremely low. so I got her going and warm, seamed to be running and responding right, but my guess is dead pump (pumps quite a few years old), lines are newer and tank is clean.


Do pumps work and not work as they are dying? i know i can pull the line off the carb and check, but the intermittent part of my problem seams to be that 'something' is dying.


I have been driving her without issues for the past two weeks, this just started. she purrs normally and fires right up with a single pump.


any advise? should i add a 30 buck electric pump to help prim it up, or just replace the mechanical, or even both?

 

Do you mean she purrs normally "again", or normally she purrs? If it hasn't straightened out my 1st reaction is timing chain. When you were driving it hard and then let off I think the nylon on the cam gear broke off. Or the pin holding the Dizzy gear where it's supposed to be sheared. Move the crank back and forth by hand (and tools) at the vibration damper bolt watching the Dizzy's rotor. See if the rotor responds right away to you moving the crank or not. And spin the crank around so the timing mark is on TDC and see if the rotor is still pointing at cyl #1 terminal.

 

she purrs normally, this bog/sputter crap is new today, once i got the pump responding she was back to normal.

 

There are a lot of things to check and the fuel delivery is easy to check but you haven't even done that. Most of diagnostics has procedures that aren't just making guesses and throwing parts at it.

 

Sorry if I wasn't clear with my question can a pump being interment it when it's dying. It's working now but this morning I don't think it was

 

Not usually but it is possible. There are one way valves in there that normally let inbound gas stay inbound and the opposite for the outbound port. Maybe one of these is on it's way out.

 

Is the mechanical pump the one with a canister? If so have you replaced the filter inside of it?

 

Filter is newer. I'm just puzzled. Carb rebuilt last month, lines replaced last summer, been running and starting perfect. I can try another filter, I just want to fix before being stranded.

 

Puzzled that it came and went. Might just add an electric to help.

 

Take the fuel line off of the carb, put a hose on the metal tubing and get a 1 gal container. Have a friend crank the engine over as you point the hose into the container. It should have a strong surge of gas coming out. If it's just going out in sperts or drooling, check/replace the filter. Try again, same problem, get a new pump. Quality electric or stay with stock pump. You don't need or want both.

 

Rubber lines between the tank and fuel pump can crack and suck air, even intermittently. I never replace a "bad" fuel pump unitil I check with a vacuum pump and a catch jar to make sure a good flow is available TO the pump. Also I've seen issues with the cam that drives the pump, though not often.

 

So it's sucking at the canister. Pump and lines checked clear and good. Found it leaking today. Bought new filter and gasket but I can't get it to seal, like the gasket is to large. In the can it fits but flares on the pump. Unless I can get another gasket or shrink this one... I think I'm stuck again. Wasted and wearing gasoline with ice cold beer scratching my head. I had a hard time last time I changed the filter, but it sealed. Found crappy in the can too so I was sucking air and clogged.

 

Anyone seal the gasket to the can? If the can sides were higher it would hold in the gasket. I'm thinking to seal the gasket to the can or replace the whole pump.

 

I wonder if the filter can was screwed on too tight. "Flaring?"

I replaced mine with an electric 'Facet' pump about 15 years ago. Solved the high-altitude vapor-lock issue above 10,000 feet as a side benefit. And fills the carb after sitting for months. $50 ?

 

Got a new can, and new filter/gasket. running again!