Am I pumping and cranking too much to start

[AuroraGirl]

I do not actually have a line running to the front for the breather. It terminates about 4 inches off my tank with a rubber hose with a steel bolt and thread sealant on its threads jammed in and clamped. (both ends clamped, fancy I know.) So I would just assume run a 3/8 (or was it 1/4) line not far from the tank if possible.

 

[Rusty Nail]

You wouldnt have to use a hose at all, clamp it on the tank fitting, NP.
I guess you could run a hose if you go mojave or make your truck try to swim like some others.. I do not forsee clamping a universal breather directly to the tank as a problem but I should prolly disclaimer that anyway.* Some of you weirdos drive your trucks into water on purpose!
*think differential vent

It's definitely not 1/4 , but it may be 5/16.

Pretty sure it is actually. 5/16...

****, you could fix it for free?
Take the bolt out and verify that fix before investing in a $5 breather..lol 5 bucks is 5 bucks!

OR
You could just take the gas cap off. - that will fix it.

 

[75gmck25]

I'd vote for a new fuel pump as the first change if you have trouble starting after sitting only 3 days.

I had slow start issues for quite a while, and then one day while looking at the engine while it was running I realized fuel was shooting out of the weep hole in the pump and evaporating on the exhaust manifold. I had smelled fuel before, but could never find the leak. I assume that whatever pump failure allowed this leak may have also caused the pump to loose prime each time the engine was shut down. Replacing the fuel pump seems to have resolved near all of my starting issues.

My truck has been sitting for at least a week and its about 25 degrees. To start it today I would pump the accelerator about 3 times, and then turn it over for about 5-6 seconds. I would then pump it again about 3 times and the next time I turn the key it will fire and the engine will run. In warmer weather it won't take the 2nd round of pumps to get it going. Once it is warmed up I just leave my foot off the pedal and hit the starter, and it fires right up.

One caveat is that my engine is still quite cold-blooded. In this weather I would probably need to let it idle and warm up at least five minutes before it will pull smoothly from idle. However, I have aluminum heads and no exhaust cross-over heat or heated air intake, so it take a while for the intake and heads to get warm.

I am using a Quadrajet, and cold starting works better for my engine if I pump it 2-3 times and then leave my foot off the pedal. I think this is because it allows the Quadrajet choke pull-off to work and lean out the mixture about 5-10 seconds after it starts, but leaves the throttle linkage on high idle. This technique is probably not applicable to an Edelbrock, since I don't think it has a vacuum choke pull-off.

Bruce

 

[78C10BigTen]

I'll try one more time to answer your questions. Some theory and facts: First you have already identified the problem. There is no fuel in the carb. The original carbs on this engine, either the Rochester 2 barrel or quadrajet would have a small fuel filter in the inlet of the carb. This filter would have a check valve, (for anti-siphon).

You also said the fuel pump is old. It also has a check valve. Modern gasoline is not friendly too the rubber parts in old fuel systems. The fuel pump must still work even if the check valve is leaking a little. But when you shut off the running engine and it sits a couple days the small leak in the check valve allows the fuel to siphon back to the tank.



Same problem with his Edelbrock. But replaced with a guadrajet fixed.....???

That Q-jet had a filter with a check valve.





I did not see a picture but I bet he has a newer fuel pump. More compatible with the crap fuel we have now.



I did not want to tell you to replace that old fuel pump because it still works. But with no second check valve and a most likely very tired check valve in the fuel pump, the fuel siphons down.

Summery: You identified the problem. You listed the possible cause, (fuel pump) and I just suggested an easy fix. Add the anti-siphon check valve.


@FireTruck1984 The exhaust manifold on the other side has no gremlins. One is not like the other.

@CoggedBelt75 I see a lot of things that could be dressed up a little. Driver's side, invisible front bolt on the intake manifold caught my eye.

@Turbo4whl my pump is a plain stock pump, nothing fancy... in fact ive never changed it. I can get pics later

 

[Turbo4whl]

A vented gas cap only allows for expansion of vapor.
Since you have cleverly plugged the evap line, the idea is your gas tank now holds vacuum and thus, sucks the line dry given the opportunity. Bet that tank hisses like a snake at the pump!

Eager to entertain other's ideas.

This could be a possibility only if another symptom exists. That symptom would be after running the engine for some time, it would shut off. Shut off because the vacuum created in the tank will be so great that the fuel pump can no longer deliver fuel to the carb.

The OP, Taylor, never stated this as a condition. Since you, Rusty, asked for an idea, I believe you are in left field with this.

 

[Kevin McDermand]

I'd vote for a new fuel pump as the first change if you have trouble starting after sitting only 3 days.

I had slow start issues for quite a while, and then one day while looking at the engine while it was running I realized fuel was shooting out of the weep hole in the pump and evaporating on the exhaust manifold. I had smelled fuel before, but could never find the leak. I assume that whatever pump failure allowed this leak may have also caused the pump to loose prime each time the engine was shut down. Replacing the fuel pump seems to have resolved near all of my starting issues.

My truck has been sitting for at least a week and its about 25 degrees. To start it today I would pump the accelerator about 3 times, and then turn it over for about 5-6 seconds. I would then pump it again about 3 times and the next time I turn the key it will fire and the engine will run. In warmer weather it won't take the 2nd round of pumps to get it going. Once it is warmed up I just leave my foot off the pedal and hit the starter, and it fires right up.

One caveat is that my engine is still quite cold-blooded. In this weather I would probably need to let it idle and warm up at least five minutes before it will pull smoothly from idle. However, I have aluminum heads and no exhaust cross-over heat or heated air intake, so it take a while for the intake and heads to get warm.

I am using a Quadrajet, and cold starting works better for my engine if I pump it 2-3 times and then leave my foot off the pedal. I think this is because it allows the Quadrajet choke pull-off to work and lean out the mixture about 5-10 seconds after it starts, but leaves the throttle linkage on high idle. This technique is probably not applicable to an Edelbrock, since I don't think it has a vacuum choke pull-off.

Bruce

This was just like my truck. The PO stated to pump it 3 times to start. At first mine would start on one pump or two, always had a gas smell lingering but didn't see anything. Then got to where no amount of pumping would start it if it sat more than a couple days. So we would use starting fluid. Then one day the fuel pump started leaking all over the place. I replaced it and now one pump to set the choke and it starts pretty quick.

 

[Rusty Nail]

This could be a possibility only if another symptom exists. That symptom would be after running the engine for some time, it would shut off. Shut off because the vacuum created in the tank will be so great that the fuel pump can no longer deliver fuel to the carb.

The OP, Taylor, never stated this as a condition. Since you, Rusty, asked for an idea, I believe you are in left field with this.

That may be.
*Been playin left field since I was a kid.
I live there now. Haha.

Symptoms would be more different or* more pronounced in hotter climate. . I bet today we find more clues!
Blues!
We all put our heads together - we cant lose!
I'm still at take the gas cap off to see what happens. Diagnosing automobile repair on the internet sure is fun!
And at these prices???


Sure it probably needs a fuel pump but that is guessing and throwing parts around that cost money.
I always start at the simplest, cheapest point to diagnose.
1. Free
2. 5 bucks

I might as well tap out now , i got no other interest. usually I unfollow these threads after my speil because i'm done here.
Some of yous got other ideas, there is room for all , I stand on the cheap ones
* almost always

 

[78C10BigTen]

@AuroraGirl i just made a cold start vid of my truck for you to see. Been sitting since friday after work and its now sunday about 4:15.

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Also for @Turbo4whl heres a picture of my fuel pump, just stock. Also my other heater hose goes to the radiator.

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[Craig Nedrow]

USE A VACUUM/FUEL PRESSURE GAUGE ON THE OUTLET AND SEE IF YOU HAVE AROUND 6 PSI. LEAVE IT ATTACHED TO SEE IF THE PRESSURE GOES DOWN. I HAVE ALMOST THE IDENTICAL SETUP, AND ALWAYS HAVE TO CRANK AND PUMP TO GET IT STARTED.

 

[SirRobyn0]

I'll admit I did not read all the responses, but I'm going to post and maybe there will be something in it that has not been brought up. Rule of thumb at the shop, each carb / engine can be different during cold starts, state of tune and internal wear can make a difference. But no more than 3 pumps of gas, then crank and it should start, anything more than that is excessive.

On my truck I have an edlebrock on stock intake, even down into the 20s after sitting a week, one pump of gas and a little cranking it will fire up, idle smooth right away and if you wanted to you could put it in gear and drive right off. Idle is just a touch over hot idle nothing excessively high. I've also got an old hearse with a caddy 425, it can sit for months at a time, and the most it'll take 1 pump of gas, if it does start on the first attempt, it's start with a 2nd pump. My point is the cold start drama your experiencing is not normal at all. and there is no reason you should have to put up with it. 90% of the time what you have going on it caused by a fuel pump that is failing. replace it make sure your choke shuts all the way when cold, and it should fire up easy.

 

[AuroraGirl]

I have noticed in slightly warmer weather we've been having the immense decrease in pumping. so I check under the hood everytime. My fuel filter is staying full, and it requires about 5 pumps after a week(a drastic decrease). But I noticed something. my filter is slowly filling with black... residue of some kind. Because the tank and rubber lines are new, Id venture to say there is either somethign in the fuel pump or something internal like a diaphram or rubber gasket is degrading and with time the rubber is breaking up. And in warm the rubber is more supply and has less tolerances, so maybe it doesnt wear as fast as -20 when the fuel filter is empty and its pulling real hard on -20 degree rubber.

Ill change the pump and filter, adding a check valve and will report back. May have to give me a few days.

 

[AuroraGirl]

So we had a warm snap, and instantly the truck started after 2 pumps(didnt try 1, might have worked) after not running for a week. It was really close to stalling out with application of throttle for about a minute, but it did idle comfortably. I looked under the hood after starting and noticed the fuel fitler was pretty much empty with a very slow increase in volume as it idled. Im guessing that tells me it warmed enough to expand some gaskets or close tolerances but still enough to take a while to get up to snuff. Maybe. I got a fuel pump and the check valve. Just gotta put em in.

 

[Frankenchevy]

Did you ever check choke function?

 

[AuroraGirl]

Did you ever check choke function?

sorry i never responded. yes i did

BUT, another follow up:

after recently adjusting timing by advancing the distributor, quite a bit... ive found(its only been hot, no idea cold) that it DOES NOT like all the extra fuel, even after 2 weeks. I literally had a 2 week period, gave one pump, and she started right up! the last 2 week period i gave three and it took long and really putted for a few seconds because it flooded

My timing was too retarded.

still gonna do fuel pump and i see edelbrock and others sell a hard line kit that sneaks under carb all nice.

 

[wanderinthru]

sorry i never responded. yes i did

BUT, another follow up:

after recently adjusting timing by advancing the distributor, quite a bit... ive found(its only been hot, no idea cold) that it DOES NOT like all the extra fuel, even after 2 weeks. I literally had a 2 week period, gave one pump, and she started right up! the last 2 week period i gave three and it took long and really putted for a few seconds because it flooded

My timing was too retarded.

still gonna do fuel pump and i see edelbrock and others sell a hard line kit that sneaks under carb all nice.

An interesting read to me! All of mine, Elderbrock and Q jets, both brand new and old fuel pumps, all take some cranking when left sitting for 4/5 ish or more days. By cranking I mean 10 to 15 seconds. Ran daily or every other day the just crank right up, the 2 elderbrocks with no pumps the Q jets with generally one, done as soon as I hit the key. The 70, "mater" I just pour gas down the carb when he has been sitting, it will never pump up with the starter??