Hi. Apologies for long winded questions/background but I'm up to my neck in a rebuild and a novice at best on my first project car so have some mercy on me as I need help on a few things going on all at once.

First, top half of the engine was rebuilt and put in several new components such as new fuel tank, fuel lines, mechanical pump, sending unit and a rebuilt QJet. Was finally able to try to fire it up and to get it started, I manually put about 2-3 ounces of fuel in the bowl via the vent tube and waited for the mechanical pump to kick in. As some background, there is only about 2 gallons of fuel in the tank to start. After it started, I checked to see if there was fuel coming from the pump and the line is dry. As the pump and sending unit are brand new, I wanted to see if there are other things I can look at in addition to those. For example, is 2 gallons of gas enough to begin test fires and to be pulled to the pump/carb or is that too little? If it IS enough, should I replace the pump with another one or how can I test that piece?

Second (which may be part of the 1st problem) is that the fuel sending unit gives a reading of E at all times. I believe this may be due to the fact that the ground is not a very good one and I'm going to relocate the ground to a more solid spot for a better connection to metal. The question for this part is if not having a good ground effect anything besides inaccurate reading on the gauge?

Lastly, as it was running/warming up, I had my timing light hooked up and it was reading around 1150 rpm's while running smoothly. Anything lower than this would cause hesitation and stalling. Once it warmed up, anything less than about 1400 would cause a stall. I'm going to hook up a vacuum gauge to test that but wasn't sure if there were some initial first steps I should be diagnosing. The idle mixture screws were set all the way in, then backed out about 2.5 turns. Couldn't keep the engine running long enough to really do enough messing around with them as there wasn't fuel actively coming from the pump, the engine would stall until I filled the fuel bowl with a little more gas via the vent.

Again....I know this post is all over the place but any help in the simplest terms would be greatly appreciated. I'm not savvy enough to know what to test and where and this is my 1st major project and trying to learn as I go.

 

my 70 manual states 6 turns out to start on the idle mixture screws.

i would get the fuel delivery squared away before trying to tune the engine at all, IDK if the line /pump needs a prime or not ?

 

I would add at least 2 more gallons of gas and also run your mixture screws back in
and bring them out 3 1/4 turns to begin and go again. Sounds like your getting there,
good luck.

 

When you say top end rebuild, was it a cam and lifter change? timing chain. If you could elaborate on what was rebuilt that would help.
The ground wire will effect your fuel level only if not ground properly, won't affect the way it starts or runs.
I would add more fuel to the tank, turn the idle screw on the carb back, then start turning the distributor until it runs on its own.
Then turn the idle screw in until its idling properly.
Turn the mixture screw out another turn, then check with vacuum gauge .
Others will add much more to assist.
I hope this helps a little
Eric

 

Thanks Eric.

To add to the top end rebuild, the heads were removed and milled, tested for leaks and then non-adjustable setup was replaced with CompCams springs and valves. Also replaced pushrods, lifters (hydraulic flat tappet), swapped stock manifold for Edelbrock Performer and had the QJet rebuilt. No changes to timing chain, cam, etc.

One portion I left out is that the tank was a single vent as there is no return line and this was how the car always was. I added a surge valve to the vent line and ran 3/8 line from the new stainless fuel line to the tank. Now that I think of it, that piece of hose from the line to the tank may be a bit too long as there was a bit of a bend in it. Perhaps I should shorten that as it may be crimping or slamming shut when fuel is being pulled?

 

You can test the fuel pump by running a rubber hose from the inlet of the fuel pump into a gas can. This will give you an idea if the pump is working properly and if maybe there is an air leak somewhere in the line from the tank to the pump.

As for the sending unit, if the ground is loose/disconnected, the gauge will read all the way to the right past FULL. This will not have any impact on whether the fuel pump is pulling fuel from the tank and the engine is running well or not. A gauge reading of E all the time sounds like the wire from the gauge to the sending unit may be grounded. Look for a pinched wire.


You said the heads were milled and non-adjustable valvetrain was used. Do you know how much the heads were milled, or did you check the lifter preload? It is possible that the non-adjustable valvetrain geometry is not correct and some valves are hanging open. I'm not saying this is the issue, just that it could be an issue if the head were milled significantly and incorrect length push rods were used.

 

The timing chain is usually done, even if it has few miles due to the nylon cam gear teeth falling off and getting sucked into the oil pick up. Look for loose and crimped connections in your fuel lines, both will cause issues. I actually had to use compressed air in the tank on a 77 Dodge van for the pump to start pulling, it sat for an unknown amount of time.