Engine Hot....hard to start
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Engine Hot....hard to start
OK...I have searched the forum for the answer and can't seem to find exactly what I need...
Here's the problem.....When the engine is cold, it starts up just fine (the choke sets and she fires right up) BUT after the engine gets to operating temps, she's a BEAR to start. It'll crank and crank and crank and crank and finally kick over. After that she runs like a "raped ape"...no black smoke, purrs at 650RPM in drive and runs really strong!
Here are the specs:
--- HEI ignition - Mallory Distributor (about 2 years old)
---350 with a Holley Street Avenger . The carb has been lately overhauled. I set the float level (the gas just dribbles out of the viewing hole with the engine running). I set the air/fuel mixture to get the most vacuum (14-15"). There's no dieseling or backfiring.
---I set the timing to 6.5*BTDC
---Changed the plugs in July of last year.
---New Taylor Stainless Steel braided plug wires (properly grounded).
I't just a PITA the start when hot..It's kinda embarasing when you jump in your Vette with a couple of Rustangs watching and you go to start and she goes "R-R-R-R-R-R-R-Varoom?"
Is the coil going out? I'm going to change the plugs again....looking for fouled plugs?
Here's the problem.....When the engine is cold, it starts up just fine (the choke sets and she fires right up) BUT after the engine gets to operating temps, she's a BEAR to start. It'll crank and crank and crank and crank and finally kick over. After that she runs like a "raped ape"...no black smoke, purrs at 650RPM in drive and runs really strong!
Here are the specs:
--- HEI ignition - Mallory Distributor (about 2 years old)
---350 with a Holley Street Avenger . The carb has been lately overhauled. I set the float level (the gas just dribbles out of the viewing hole with the engine running). I set the air/fuel mixture to get the most vacuum (14-15"). There's no dieseling or backfiring.
---I set the timing to 6.5*BTDC
---Changed the plugs in July of last year.
---New Taylor Stainless Steel braided plug wires (properly grounded).
I't just a PITA the start when hot..It's kinda embarasing when you jump in your Vette with a couple of Rustangs watching and you go to start and she goes "R-R-R-R-R-R-R-Varoom?"
Is the coil going out? I'm going to change the plugs again....looking for fouled plugs?
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
It may be necessary for you to shield the stater from "heat soaking"...there are products and new starters that will help you address this ....I have had that dragging...and at times... a no starter, condition, when things get good and hot. I just lifted the hood for a few minutes..cooler down a bit...and she would crank right up. I now have a heat shield and a heat soak resistant starter .
Do you have an electric choke on the carb? I had an issue where the electric choke kicks in even when the engine is up to temp. Makes it one hell of a PITA to start after shutting it down for a short period. I just disabled the choke... I really dont need it.
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
That doesnt sound like the issue here.
Do you have an electric choke on the carb? I had an issue where the electric choke kicks in even when the engine is up to temp. Makes it one hell of a PITA to start after shutting it down for a short period. I just disabled the choke... I really dont need it.
Do you have an electric choke on the carb? I had an issue where the electric choke kicks in even when the engine is up to temp. Makes it one hell of a PITA to start after shutting it down for a short period. I just disabled the choke... I really dont need it.
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
Pull the air cleaner off and open up the choke butterflys by hand (while its up to temp). Have someone crank it.
If it runs smooth (which it probably will) you've found your problem.
This same thing chapped my a$$ for a while. Finally got sick of it and safety wired the choke open, and disconnected power from the electric unit. Now, when cold, it takes a little feathering of the throttle to get her going good, but nothing that bothers me.
If it runs smooth (which it probably will) you've found your problem.
This same thing chapped my a$$ for a while. Finally got sick of it and safety wired the choke open, and disconnected power from the electric unit. Now, when cold, it takes a little feathering of the throttle to get her going good, but nothing that bothers me.
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
It runs smooth....it's just a PITA to start when hot. So you're saying when it's hot, take off the air cleaner and see if the choke sets? If it does, how do I keep it from setting when the engine is hot?
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Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Do what panic does.
If you don't touch the pedal the choke won't reset the choke linkage. In addition you can either leave the key on a bit before you start the engine to heat up the elec element or let it idle a bit after it is started so it doen't reset to the choke setting.
BTW check you cold and hot settings first.
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Do what panic does.
If you don't touch the pedal the choke won't reset the choke linkage. In addition you can either leave the key on a bit before you start the engine to heat up the elec element or let it idle a bit after it is started so it doen't reset to the choke setting.
BTW check you cold and hot settings first.
Last edited by vetteguy75; Mar 4, 2007 at 09:09 AM.
Le Mans Master
Joined: Apr 2000
Posts: 7,562
Likes: 9
From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Have you checked your timing? I built a motor for a Camaro I used to own and it started great. I didn't have a timing light so I set it by ear at the time. It ran great, but if I were to shut it off after driving it a bit, it would turn over really slow as if the battery was about died. Once cooled, the engine turned off fine. I backed the timing off some and the problem went away 
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
You could get by with a little more gap than people in the far north becuse of your location and temps.
Some people set it by the book though.
I don't use the choke at all where I live.
Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
I can't see how it is a starter issue, but, just to be safe, Corvette starters do have heat shields to keep them from getting heat soaked.
I would take a guess at vapor lock. Noting that you are in the sunny and warm south I would say that the heat from your block is boiling your fuel out. Pull your air cleaner cover and look down the carb while someone cranks. When you have a warmed up engine, ready to start, what happens when you pump the gas pedal without cranking the engine? Do you see fuel being squirted out and into the carb? If not, then you have a fuel starvation issue. The other thing is setting the fuel level. My Holley calls for setting the fuel level in the bowl so that is right at the base of the hole, not dribbling out.
I would take a guess at vapor lock. Noting that you are in the sunny and warm south I would say that the heat from your block is boiling your fuel out. Pull your air cleaner cover and look down the carb while someone cranks. When you have a warmed up engine, ready to start, what happens when you pump the gas pedal without cranking the engine? Do you see fuel being squirted out and into the carb? If not, then you have a fuel starvation issue. The other thing is setting the fuel level. My Holley calls for setting the fuel level in the bowl so that is right at the base of the hole, not dribbling out.
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
Heat soak makes it difficult to CRANK the engine... from what I've gathered here, looks like vetteguy75 is not having this issue, but he is having an issue with it running properly just after startup. Which means its cranking fine, no?
Care to clarify to help narrow down the possibilities?
Care to clarify to help narrow down the possibilities?
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Heat soak makes it difficult to CRANK the engine... from what I've gathered here, looks like vetteguy75 is not having this issue, but he is having an issue with it running properly just after startup. Which means its cranking fine, no?
Care to clarify to help narrow down the possibilities?
Care to clarify to help narrow down the possibilities?
Thanks.....No, it's running fine after I get it started....it's just hard to start when it's hot or "up to temperature" and it sits for about 20 minutes. If I shut the engine down (after running it) and wait 2-5 minutes, she'll fire up just fine...but if it's sitting about 20-25 minutes, it'll will sound something like this...."R-R-R-R-R-R-Varoom"
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Nope, stock exhaust system with dual exhaust....but the passenger side pipe is within 1/2" of the starter PLUS it is the original starter. The car has 105,000 miles on her....do you think it is the starter????? I'm sorta leaning in that direction....I changed the plugs out this afternoon and they were all perfect (really didn't need to change them...but since I already had new ones...I replaced them).
Just thought of something that may help....about 3-4 weeks ago, I had to jump start the Vette (old battery + cold weather + not driving it for 2 weeks = slightly dead battery...since then I got a new battery)...anyway...I accidently put the positive lead from the other battery to the negative post on the Vette and vice-versa. Tried to start the car and realized "OH $hi#!!! what I did wrong!!!!!!! Thank God nothing blew...no fuses, no fuseable links...nothing. Could that have weaken the starter???
Just thought of something that may help....about 3-4 weeks ago, I had to jump start the Vette (old battery + cold weather + not driving it for 2 weeks = slightly dead battery...since then I got a new battery)...anyway...I accidently put the positive lead from the other battery to the negative post on the Vette and vice-versa. Tried to start the car and realized "OH $hi#!!!
what I did wrong!!!!!!! Thank God nothing blew...no fuses, no fuseable links...nothing. Could that have weaken the starter???
Instructor
Joined: Dec 2006
Posts: 167
Likes: 0
From: Oxnard/San Luis Obispo CA
The reason I thought it could be the starter was because I just recently had the exact same problem, but I have headers and the starter was pretty much touching the headers. I got a mini style starter and the problem went away. However, since you dont have headers it could be something else. My money would be on the starter though since GM starters are notorius for having hot starting issues when they get old.
