getting depressed
Le Mans Master
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From: Western Massachusetts
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the reason he swapped out the coil was the one in there had been crushed as it was larger than the original and , the guy who put that one in wasnt the sharpest tool in the shed i soon found out . The guy i use now is tried and true does a lot of cars here on the cape and knows his stuff and actually had a couiple c2's in the past . Hes not the type to throw parts at it. when he saw that it was crushed he decided to replace it and said it was red hot when he pulled it.
You will get a lot of advice, most of it good, but none of it useful to you UNTIL you know whether the problem is fuel or spark. When it acts up you have to get out & prove a fuel or spark problem before it cools and the evidence is gone. Being on the Cape in August is not a great spot to find mechanics worth a ****, especially ones that know carbureted and distributor equipped mid century domestic engines. As Frank said, diagnosis is what you need, not answers to the question "what could it be?"
Dan
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Frankly, this sounds like a fuel percolation problem to me. The coil was replaced due to damage, not as a solution to this problem and that introduced a red herring into the troubleshooting. I would attack this problem as a hot carb problem and proceed as folks have indicated above.
Now, your second potential issue is your electronic ignition set up. Most want 12v at the coil which means no ballast, but there are some that do require ballast. Also, the coil primary impedance is critical. You need to find the instructions for your ignition set up and ensure all of the components are properly matched. Posting the specific set up on your engine will allow us to help. Otherwise, we are grasping at straws. Reinstalling the points distributor is just silly talk.
Now, your second potential issue is your electronic ignition set up. Most want 12v at the coil which means no ballast, but there are some that do require ballast. Also, the coil primary impedance is critical. You need to find the instructions for your ignition set up and ensure all of the components are properly matched. Posting the specific set up on your engine will allow us to help. Otherwise, we are grasping at straws. Reinstalling the points distributor is just silly talk.
Le Mans Master
Joined: Feb 2012
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From: Western Massachusetts
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The first step in troubleshooting is visual inspection of a known configuration. We have neither, yet are trying to jump steps. My response was an attempt to get the required information in order to proceed, while sharing my perspective based on what was shared. This is always the problem with trying to troubleshoot without firsthand knowledge.
Drifting
Joined: Apr 2008
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From: Lexington Park Maryland
Why ?? It would help the OP figure out whether they have a fuel or electrical issue (key word "help"). It seems there's some confusion of how the ignition is/is not hooked up on their car and whether it's hooked up correctly. I didn't say leave the points in forever.. The OP can go back to the electronic set up once the ignition is eliminated as the culprit. FWIW...., I rebuilt my L79 back in '90 and still run the original style points distro today, which is working fine.
Le Mans Master
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Thread Starter
Pro
Joined: Sep 2007
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From: cape cod MA
The first step in troubleshooting is visual inspection of a known configuration. We have neither, yet are trying to jump steps. My response was an attempt to get the required information in order to proceed, while sharing my perspective based on what was shared. This is always the problem with trying to troubleshoot without firsthand knowledge.
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After driving enough to fully warm up the engine, let it idle for a few minutes, then open the hood and check manifold temps with an IR gun held a couple of inches away so the observed "cone" doesn't pick up any cooler background temperatures. If they are more than about 500F, then there's something wrong with the spark advance map, like an incorrect or dead VAC, or Bubba plugged the signal line with a BB. Also shoot the carb bowls, thermostat housing, upper hose, and radiator inlet nipple. Post your data.
Hot manifolds will considerably raise underhood temps, which will cause fuel percolation that requires the flooded engine start procedure. Also, any kind of electrics can be affected by high temperature like an aftermarket electronic switch that replaces the points, when points will keep on working without protest.
Duke
Hot manifolds will considerably raise underhood temps, which will cause fuel percolation that requires the flooded engine start procedure. Also, any kind of electrics can be affected by high temperature like an aftermarket electronic switch that replaces the points, when points will keep on working without protest.
Duke
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sorry guys i got sidetracked , i do have the mallory electronic module in there right now and i am attempting to get it out so i can replace it,, i also intend to get the fuel filter up off the intake as much as possible and wire open the butterfly on the passenger side exhast . I am having trouble getting at the module is there some kinda trick in getting it out ? I got the rotor cap and rotor off but cant get at the screws that hold the module in there any help is appreciated
Steve
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Is this the module you have installed in your stock distributor?
https://static.summitracing.com/glob..._gm_61001M.pdf
If so, your choice of coil and use of a ballast resistor or not is critical. If this is the module, please read the directions posted and ensure you either use the ballast resistor with a stock coil or one of the listed coils without a ballast resistor. This could be your problem and if improper components were used, overtime you could have damaged the Mallory module.
https://static.summitracing.com/glob..._gm_61001M.pdf
If so, your choice of coil and use of a ballast resistor or not is critical. If this is the module, please read the directions posted and ensure you either use the ballast resistor with a stock coil or one of the listed coils without a ballast resistor. This could be your problem and if improper components were used, overtime you could have damaged the Mallory module.
Racer
Joined: May 2017
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I have a 65 with an L-76, 365hp and was having the exact same issue. Drive for a bit on a hot day, go to get gas or get a sandwich and it wouldn't restart. It restarted just fine after cooling off. After doing some reading and with advice from others on this forum, I decided it was a percolation issue and decided to install a heat shield. Well, when I went to install the summit racing heat shield, I managed to break off a mounting tab on my carburetor because the heat shield riser (which I now know I should not have used) was cheap compressible material.
So after getting advice from TripleBlack (RIP), I decided to replace the Holley with a Quick Fuel Black Diamond carburetor, which advertises as having a coating that helps keep the carburetor temp down. I can tell you first hand that it worked perfectly out of the box and I have not had any issues with starts since.
https://www.holley.com/products/fuel.../parts/BD-1957
This is just my experience, take it for what it's worth.
So after getting advice from TripleBlack (RIP), I decided to replace the Holley with a Quick Fuel Black Diamond carburetor, which advertises as having a coating that helps keep the carburetor temp down. I can tell you first hand that it worked perfectly out of the box and I have not had any issues with starts since.
https://www.holley.com/products/fuel.../parts/BD-1957
This is just my experience, take it for what it's worth.
Last edited by RJMerc; Aug 17, 2018 at 11:49 AM.
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From: Camp Verde AZ
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You have an inline fuel filter between the pump and carb?
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
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Pro
Joined: Sep 2007
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From: cape cod MA
well now my computer is acting up and i cant read the link but i looked up what u posted and it is similar to that one , but i cant get to the module 04249 is all i can read on the module something lite i dont know if its e-lite or not
Thread Starter
Pro
Joined: Sep 2007
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From: cape cod MA
You have an inline fuel filter between the pump and carb?
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Thread Starter
Pro
Joined: Sep 2007
Posts: 699
Likes: 53
From: cape cod MA
You have an inline fuel filter between the pump and carb?
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Thread Starter
Pro
Joined: Sep 2007
Posts: 699
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From: cape cod MA
I have a 65 with an L-76, 365hp and was having the exact same issue. Drive for a bit on a hot day, go to get gas or get a sandwich and it wouldn't restart. It restarted just fine after cooling off. After doing some reading and with advice from others on this forum, I decided it was a percolation issue and decided to install a heat shield. Well, when I went to install the summit racing heat shield, I managed to break off a mounting tab on my carburetor because the heat shield riser (which I now know I should not have used) was cheap compressible material.
So after getting advice from TripleBlack (RIP), I decided to replace the Holley with a Quick Fuel Black Diamond carburetor, which advertises as having a coating that helps keep the carburetor temp down. I can tell you first hand that it worked perfectly out of the box and I have not had any issues with starts since.
https://www.holley.com/products/fuel.../parts/BD-1957
This is just my experience, take it for what it's worth.
So after getting advice from TripleBlack (RIP), I decided to replace the Holley with a Quick Fuel Black Diamond carburetor, which advertises as having a coating that helps keep the carburetor temp down. I can tell you first hand that it worked perfectly out of the box and I have not had any issues with starts since.
https://www.holley.com/products/fuel.../parts/BD-1957
This is just my experience, take it for what it's worth.
Thread Starter
Pro
Joined: Sep 2007
Posts: 699
Likes: 53
From: cape cod MA
You have an inline fuel filter between the pump and carb?
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Not that that is your problem, but it will put more engine heat into the carb gas,and it is fire hazard. Hard pipe between pump and carb, or as much as you can, SAE J30R9 fuel injection hose for any part you can't.
I suspect you may ahve clogged inlet in the fuel tank,a nd you are getting fuel starvation, when its hot, you are getting vapor lock between the tank and pump, and after sitting a bit, some crud falls off the in tank sock and lets you drive for a while. When it cold out, the gas doesn't flash to vapor in the line.
Of course the coil is going to be hot, its 200 degrees under your hood and so is everything else.
Doug
Enjoy while you can.
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From: 10th District Court OHIO
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Cant help you, but I know how you feel. Been talking to Spectrum all day trying to fix a problem. Good luck on yours.