starting issue

[prin]

Ive noticed for some time now that I am having a starting issue. My truck starts fine when the motor is cold. But when it is warm, it turns over a lot more than normal before it fires. Do you guys have any suggestions on what could be my problem?

[prin]

Ive noticed for some time now that I am having a starting issue. My truck starts fine when the motor is cold. But when it is warm, it turns over a lot more than normal before it fires. Do you guys have any suggestions on what could be my problem?

[geezer#99]

What carb?
What’s your initial timing?

[homemade87]

Originally Posted by prin

Ive noticed for some time now that I am having a starting issue. My truck starts fine when the motor is cold. But when it is warm, it turns over a lot more than normal before it fires. Do you guys have any suggestions on what could be my problem?

I assume you have a carb . The one thing I have had problems such as this is the needle and seat would not hold back the fuel at shut down and will drip fuel in the intake and make the engine hard to start hot . Pretty easy to check . After running the engine for a while and up to full temp shut it down and let it set for a minute . Take the breather off and look into the carb and see if any fuel is dripping . If can not see anything open the throttle slowly ( not to shoot a lot more fuel into the carb ) wide open and see if there is a fog of fuel below the blades . If there is the carb will have to come apart and replace needle and seat or rebuild to stop the fuel .

If this is the case the engine is flooding when hot making hard to crank when hot and usually will crank fine cold .

Just one thing to check and the first thing I would check to rule it out .

[Dead Parrot]

Assuming a carb, some possible suspects:
Choke sticking partially stuck or closing while motor still hot.
Carb too hot and fuel boiling off - if you still have a exhaust heat riser valve, check for it being stuck.
Defect in fuel pump/carb needle-seat letting fuel in carb bowl drain back into tank.

[jbarron]

Gas tank not venting properly.
Check the gas cap.

[68gmsee]

It would help if you posted year, engine and whether it's carbed.

First, suspect the carb flooding if you have not done any work on the ignition system or fuel system.

Have someone look at your exhaust after it starts when warm and sitting for a few minutes. Dark gray smoke is fuel.

If carbed, check choke. If it's a qjet, leaking well plugs could be the problem.

[AcampoDave]

Edelbrock carb? Reason I ask is they tend to act like a heat sink unless they have a beefy insulator type base gasket. Like this:
https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds these help the problem but not 100%. I have had even better results with a 4 hole 1"phenolic carb spacer.

[prin]

Thanks for all of the replies. It is a late 70's 350 that bored to a 355. Im running a Holley 650 carb. I will check the carb and see if it is leaking fuel on my next drive. Its pretty annoying when you are in a crowd and it wont start right off. I do know that there is no smoke coming from it.

[68gmsee]

Originally Posted by prin

Thanks for all of the replies. It is a late 70's 350 that bored to a 355. Im running a Holley 650 carb. I will check the carb and see if it is leaking fuel on my next drive. Its pretty annoying when you are in a crowd and it wont start right off. I do know that there is no smoke coming from it.

Added questions:
Did the problem start suddenly, gradually or has it always had a starting problem? How long do you have to crank before it starts? (seconds).

As mentioned check the choke to make sure it's open when warm and check the timing.

[YoungPup1977]

Originally Posted by prin

Thanks for all of the replies. It is a late 70's 350 that bored to a 355. Im running a Holley 650 carb. I will check the carb and see if it is leaking fuel on my next drive. Its pretty annoying when you are in a crowd and it wont start right off. I do know that there is no smoke coming from it.

Next time when you are in a crowd, ask everyone if they have a timing light. Check the timing and let us all know. Thanks.

Does it still have the old points in the dizzy ?

[prin]

Originally Posted by YoungPup1977

Next time when you are in a crowd, ask everyone if they have a timing light. Check the timing and let us all know. Thanks.

Does it still have the old points in the dizzy ?

I will check it and see. What are your thoughts? Timing too high? Also, it is a later model motor so no points.

[AcampoDave]

I bet even a Holley would benefit from an insulator gasket. I've seen 'em on Quadrajets too.

[GASoline71]

It sounds like you're used to FI rigs firing right up every single time.

If you're pumping the pedal at all when the rig is warm, it'll take way longer to light off. If it's only "cranking" 5 times or so when you turn the key to start when warm... I'd say it's pretty normal.

If you have to crank it, then turn key off. Crank it again, turn key off, Etc. until it finally starts. Then you have an issue.

Gary

[bob arrington]

I suggest upgrading to
hei

[prin]

This issue has gradually started. My dad bought this truck new and it has had different motors put in it. I was fine with the way that it starts, but the few times that he took it out, he has complained as in there is a problem with it. Like said, when it is a cold start, it fires right up. But on a warm start, it turns over quite a few times and sometimes, you have to press the accelerator a little to get it started.

[geezer#99]

What’s your initial timing and have you checked it lately?

[RustyBucket]

My '71 GMC starts best warm if I just twist the key with no accelerator pedal. Usually will start just like our LS powered daily drivers. If it doesn't start on the very first turn or two, I ease a little accelerator pedal on as it's turning. If I step on the gas before turning the key, it has to turn awhile before it starts. When it's cold I push the accelerator pedal down once lightly to set the choke/fast idle and take my foot off the pedal.. turn the key and it fires right off on fast idle 'till I blip the throttle. Original 350 engine, HEI dist, 650 Holley, Edelbrock Performer intake, cast iron exh. manifolds.

[prin]

Originally Posted by geezer#99

What’s your initial timing and have you checked it lately?

It hasn't been checked lately

[geezer#99]

Originally Posted by prin

It hasn't been checked lately

And what’s your initial timing?

[YoungPup1977]

Check the timing first, see where it is and than go from there. Let us know the process of how you checked your timing. thanks...

The reason I mentioned points was from post #12 about upgrading to HEI. Thought he knew something about your vehicle more than what was already mentioned.

[bob arrington]

starter heat soak

[YoungPup1977]

Originally Posted by bob arrington

starter heat soak

Are you suggesting a shield on the starter would fix the heat soak issue.

[franken]

Originally Posted by bob arrington

starter heat soak

Nothing in the thread suggests the starter is cranking slowly so nothing suggests heat soak, which is generally a myth. Slow cranking is usually caused by faulty wiring so let's try yo keep the nonsense to a minimum.

I'd try pressing the gas to the floor when cranking warm. If it starts quicker the carb might be dripping gas out of the bowls.

A warm tuned SBC typically fires with a touch of cranking and no stepping on the gas.

[YoungPup1977]

Originally Posted by franken

Nothing in the thread suggests the starter is cranking slowly so nothing suggests heat soak, which is generally a myth. Slow cranking is usually caused by faulty wiring so let's try yo keep the nonsense to a minimum.

I'd try pressing the gas to the floor when cranking warm. If it starts quicker the carb might be dripping gas out of the bowls.

A warm tuned SBC typically fires with a touch of cranking and no stepping on the gas.

LOL. It wouldn’t be a forum without nonsense as you state. Can’t see the problem from the couch. Everyone is entitled to their opinion but let’s get feedback from OP than go from there. This forum should provide trophies for the correct answers. Love these forums. I don’t get the newspaper any more with the funnies so I read this forum. Same thing. Smh
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