hard starting (first start) of the day

[nrb's70gmc]

hay guys im having a problem with my truck when i start ifor the first time (morning)

i have to crank the motor for about 30 seconds before the engine starts.
after the first start of the day it fires right up the rest of the day.

the choke is not hooked up what i have always done is got in pumped the gas a few times and it starts up.

in the past few months i have

drained the gas tank
removed rust from the inside of the tank
reinstalled the tank
removed and cleaned carb (did not take carb apart)

after i put everything back together is when this started happining

in my opinion is seems like the starter is not turning over quick enough

so i
had the battery tested (tested ok)
had starter and selinoid tested (both tested ok)
while i had the starter out i added a ford remote selinoid

then i had to replace the gas cap, the ones they sell at orielys are plastic what ever i dont care.

but i notice when i take the new cap off the pressure almost blows the cap out of my hand. so i dont know if a vented or non vented cap would help

my fuel presure is bouncing from 6-9 psi
the truck also has a new coil and module also.

im really frusterated with this. any ideas please.
thanks.

[kray59]

sounds like the fuel is leaking out of carb and you are having to pump fuel back up to it . do you have a manual pump?

[nrb's70gmc]

Originally Posted by kray59

sounds like the fuel is leaking out of carb and you are having to pump fuel back up to it . do you have a manual pump?

ya its a mech pump, how can it leak there is not a gas oder under the hood

[cdowns]

well you need to get the proper vented gas cap is one problem you need to solve

having a working choke is another problem you should fix

with your starter problem you could take the time and cleanup your ground wire connections to improve voltage flow

i bet if you solve those three maintenance problems you'll start better in the mornings

[Autoblueprint]

Originally Posted by nrb's70gmc

hay guys im having a problem with my truck when i start ifor the first time (morning) i have to crank the motor for about 30 seconds before the engine starts. After the first start of the day it fires right up the rest of the day.

the choke is not hooked up...then i had to replace the gas cap, the ones they sell at orielys are plastic what ever i dont care...but i notice when i take the new cap off the pressure almost blows the cap out of my hand. so i dont know if a vented or non vented cap would help.

You should at least post the year, engine c.i.d. and trans type of your truck, this helps other board members who would like to help you out with your problem.

You should have an operational choke on your carb...without it...you will have hard starting problems...especially on first cold engine start...GM engineers put a choke on the carb for a reason...don't try to shortcut the factory engineering because all you will end up with are problems.

All that pressure in the fuel tank is NOT good...order the proper fuel cap from a vendor like LMC truck...I believe you need a cap that is vented.

[nrb's70gmc]

Originally Posted by cdowns

well you need to get the proper vented gas cap is one problem you need to solve

having a working choke is another problem you should fix

with your starter problem you could take the time and cleanup your ground wire connections to improve voltage flow

i bet if you solve those three maintenance problems you'll start better in the mornings

so the factory gas tanks have a vented cap? ok i will look into it

[nrb's70gmc]

Originally Posted by Autoblueprint

You should at least post the year, engine c.i.d. and trans type of your truck, this helps other board members who would like to help you out with your problem.

You should have an operational choke on your carb...without it...you will have hard starting problems...especially on first cold engine start...GM engineers put a choke on the carb for a reason...don't try to shortcut the factory engineering because all you will end up with are problems.

All that pressure in the fuel tank is NOT good...order the proper fuel cap from a vendor like LMC truck...I believe you need a cap that is vented.

sorry everything is posted in my sig trans is th350

[nrb's70gmc]

quick update

i confirmed i have a vented gas cap i took the cap of just to check the pressure there was some but not much.

i went out to see if i could figure out the the problem (truck had not been started today)
before i started the truck i looked at the fuel psi gauge the needle was right on 8 psi. i got in the truck pumped the gas once and she fired right up like old times.

my question is it normal for the fuel psi to hold fuel pressure when you turn the motor off??

to me it makes sence because it means theres fuel in the line -- if the fuel psi read 0 that would mean there is no fuel in the line correct???

[PanelDeland]

The fuel pressure should leak down if the engine isn't running,if you have a mech pump.

[nrb's70gmc]

Originally Posted by PanelDeland

The fuel pressure should leak down if the engine isn't running,if you have a mech pump.

thanks for your reply, so why or what would cause it to hold pressure?

[cdowns]

Originally Posted by nrb's70gmc

thanks for your reply, so why or what would cause it to hold pressure?

you have the wrong gascap

[Chevyman680063]

The recommended psi for an Edelbrock 600cfm carb is 6 psi and no more. I'd also fix the choke.

[nrb's70gmc]

Originally Posted by cdowns

you have the wrong gascap

As in vented-- non vented? it does have a vented cap

[cdowns]

Originally Posted by nrb's70gmc

As in vented-- non vented? it does have a vented cap

not if you have pressure buildup in your gastank//if you bought a vented gascap IT IS DEFECTIVE

[nrb's70gmc]

Originally Posted by cdowns

not if you have pressure buildup in your gastank//if you bought a vented gascap IT IS DEFECTIVE

is there anyway to test the vent holes on the cap?

could they be inlarged with a drill?

[DANTIP]

Is the Accelerator pump working? I would strongly suggest fixing the choke (you are prematurely aging your starter!!!).

[cdowns]

Originally Posted by nrb's70gmc

is there anyway to test the vent holes on the cap?

could they be inlarged with a drill?

have never done it myself but have heard of a few guys doing it to solve that problem
me i'd look to any of the board vendors for a quality repo piece that works correctly

[68gmsee]

All good recommendations above. Here's mine.

Check the pump while engine is running and make sure you have 4.5 to 5 psi as mentioned above -should pump one pint in less than 30 seconds into a plastic container. If you have to, replace it- they're cheap.

On a weekend Sat. morning when you don't have to go anywhere and before you start the truck remove the air breather and look down the throat with a flashlight while activating the throttle by hand. Should see gas squirting into the carb. If not you either have a bad accelerator pump or fuel is draining out of the bowl.

Take the carb top off and see if there's fuel in the bowl. If there isn't check the needle valve and seat (I would replace it) and if the pump isn't squirting gas or the stream is weak, replace it also.

forgot to mention: Some floats can get fuel (water)logged so check that also. If it doesn't float, the needle valve will open draining the fuel.

Check and adjust fuel float and fill the bowl with gas. Replace the top but don't screw it down all the way. Maybe just snug it. Periodically check the bowl throughout the day to see if it's draining. Check again the next morning.

If it's draining down, there's other problems in the carb.

[lil hoodlum]

Originally Posted by 68gmsee

All good recommendations above. Here's mine.

Check the pump while engine is running and make sure you have 4.5 to 5 psi as mentioned above -should pump one pint in less than 30 seconds into a plastic container. If you have to, replace it- they're cheap.

On a weekend Sat. morning when you don't have to go anywhere and before you start the truck remove the air breather and look down the throat with a flashlight while activating the throttle by hand. Should see gas squirting into the carb. If not you either have a bad accelerator pump or fuel is draining out of the bowl.

Take the carb top off and see if there's fuel in the bowl. If there isn't check the needle valve and seat (I would replace it) and if the pump isn't squirting gas or the stream is weak, replace it also.

forgot to mention: Some floats can get fuel (water)logged so check that also. If it doesn't float, the needle valve will open draining the fuel.

Check and adjust fuel float and fill the bowl with gas. Replace the top but don't screw it down all the way. Maybe just snug it. Periodically check the bowl throughout the day to see if it's draining. Check again the next morning.

If it's draining down, there's other problems in the carb.

Good advice! Basically your engine is having a hard time getting gas for your first start of the day.

I've got a part # for a vented gas cap for you. Fram PRG-23.

I was having troubles getting a vented one. Bought two locally and both turned out to be non-venting. I ended up ordering one from LMC and that is what arrived, the Fram PRG-23.

good luck!

Keith

[68gmsee]

Originally Posted by lil hoodlum

Good advice! Basically your engine is having a hard time getting gas for your first start of the day.

I've got a part # for a vented gas cap for you. Fram PRG-23.

I was having troubles getting a vented one. Bought two locally and both turned out to be non-venting. I ended up ordering one from LMC and that is what arrived, the Fram PRG-23.

good luck!

Keith

That's good info. I need to replace mine.

Here's a pic of what it should look like if anyone needs to check. There's a plunger inside the hole that opens at a certain psi of pressure to vent the tank. You should be able to stick a small nail in there and it should move and spring back.

[lil hoodlum]

Originally Posted by 68gmsee

That's good info. I need to replace mine.

Here's a pic of what it should look like if anyone needs to check. There's a plunger inside the hole that opens at a certain psi of pressure to vent the tank. You should be able to stick a small nail in there and it should move and spring back.

I allways wondered how a gas cap could be vented and not allow the gasoline to evaporate away! Now I know. Thanks 68gmsee, I learned something new today.

Keith