Hard to start
Thread Starter
Burning Brakes
Joined: Sep 2010
Posts: 799
Likes: 26
From: Lexington Park Maryland
Hard to start
I was involve in a stop and go traffic this afternnon, which eventually came to complete stop. Before that I notice the temp climed close to the 210 mark, so I decided to pull over and wait out the traffic. That's when it was hard to start this 72LT1, it turned over. It appeared not to have any spark.
I would like let seat for several minutes, it would start but poor accellation. It was not until I let is seat for awhile, after that I was able to start it without any problem. But it had a rough accellaration.
Can the coil be affected by the heat and be intermitten?
I would like let seat for several minutes, it would start but poor accellation. It was not until I let is seat for awhile, after that I was able to start it without any problem. But it had a rough accellaration.
Can the coil be affected by the heat and be intermitten?
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
210 is normal operating range. I'd say heat soak for the starter solenoid. If the factory shield in place? My 74 would occasionally be hard to start after running for a while, but it ran okay after restarting.
Thread Starter
Burning Brakes
Joined: Sep 2010
Posts: 799
Likes: 26
From: Lexington Park Maryland
I got the car home, let it seat until I got home from work. When I got home it started right up like it always does, even took it for a drive this weekend (hotter). It performed fine. Here's the question: I know the timing of a car can affect the, I had the timing at 10 BTC. I changed it when I got home, as I said it ran fine even on a much hotter day.
Drifting
Joined: Jan 2011
Posts: 1,853
Likes: 81
From: Hamilton Virginia
My apologies, the word hard start is probably not the best way to describe the situation. The starter will turn over the engine without a problem, it turns over sounding as if it lack iginition. I verifed the fuel, it was getting fuel.
I got the car home, let it seat until I got home from work. When I got home it started right up like it always does, even took it for a drive this weekend (hotter). It performed fine. Here's the question: I know the timing of a car can affect the, I had the timing at 10 BTC. I changed it when I got home, as I said it ran fine even on a much hotter day.
I got the car home, let it seat until I got home from work. When I got home it started right up like it always does, even took it for a drive this weekend (hotter). It performed fine. Here's the question: I know the timing of a car can affect the, I had the timing at 10 BTC. I changed it when I got home, as I said it ran fine even on a much hotter day.
Last edited by scrappy76; May 18, 2015 at 02:41 PM.
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
Sounds like either fuel getting hot or your coil Unless you have changed your fuel line, could be your coil getting too hot as possibly on its way out. Not positive though, a couple things to look at. One day to the next, were you sitting in traffic the next day it ran fine ?
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
If you don't have the proper ballast resistor for your coil, it can cause it to run hot also. It really sounds a lot like vapor in the lines or boiling the float bowl. I have a lot of issues when I let it sit for 15-20 minutes when it's hot. I have to crank and pump the gas to get it to start again. One of these days, I'm going to go with FI and a return line.
Safety Car
Joined: Sep 2013
Posts: 4,355
Likes: 2,633
From: Draper Utah
I had this problem and switching where I was buying gas at solved the problem. My car (70 L-46) has no problems if I buy my gas at Chevron, since I discovered the car starts easy on Chevron that's where I fill it up these days. Switching where you buy gas is worth a try to see if it fixes the problem, easy fix if it works.
Thread Starter
Burning Brakes
Joined: Sep 2010
Posts: 799
Likes: 26
From: Lexington Park Maryland
I had this problem and switching where I was buying gas at solved the problem. My car (70 L-46) has no problems if I buy my gas at Chevron, since I discovered the car starts easy on Chevron that's where I fill it up these days. Switching where you buy gas is worth a try to see if it fixes the problem, easy fix if it works.
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Instructor
Joined: Jul 1999
Posts: 138
Likes: 1
From: Brick New Jersey
Sounds as though your carb is heat soaking...... Your 72 was designed to run on leaded non ethenol fuel. On hot days and high engine temps when the car sits more then a few minutes the fuel in the bowls will percolate and cause a flooding event. When you crank the motor long enough you rid the intake of all that excess fuel she finaly starts. Next time on a hot day and the car is running hot pull the air cleaner and watch the for the fuel to percolate over and into the intake. It only takes a few minutes to start percolating over !! Test it with a tank of leaded 100 octane AV fuel and it won't percolate and may start fine. You may have to try a carburetor heat insulator...... I have the same issue with my 68 L71. When I ran the AV fuel (I fly so I haved filled up at my airport I fly out of) no percolating and starts fine when hot and sits!! I am in the process of looking at a few different carb heat insulators now. I will post a question for the best insulator tonight on the forum..... Tom.
Last edited by tomdoc; May 19, 2015 at 10:09 PM.
Thread Starter
Burning Brakes
Joined: Sep 2010
Posts: 799
Likes: 26
From: Lexington Park Maryland
Sounds as though your carb is heat soaking...... Your 70 was designed to run on leaded non ethenol fuel. On hot days and high engine temps when the car sits more then a few minutes the fuel in the bowls will percolate and cause a flooding event. When you crank the motor long enough you rid the intake of all that excess fuel she finaly starts. Next time on a hot day and the car is running hot pull the air cleaner and watch the for the fuel to percolate over and into the intake. It only takes a few minutes to start percolating over !! Test it with a tank of leaded 100 octane AV fuel and it won't percolate and may start fine. You may have to try a carburetor heat insulator...... I have the same issue with my 68 L71. When I ran the AV fuel (I fly so I haved filled up at my airport I fly out of) no percolating and starts fine when hot and sits!! I am in the process of looking at a few different carb heat insulators now. I will post a question for the best insulator tonight on the forum..... Tom.
You hit the NAIL on the head, the first time it did this. I treated it like it was flooded so I took a screw driver and forced both primary and secondary butterfly open and kept them open for a few minutes. that's when it would start. I did install an aluminum shield I got from Holley, obviously that's not doing much good.
I would be interested what you come up with, now that I can keep it cool with the fan from my Benz. I drive it more than before, of course just avoid stop and go traffic.
Instructor
Joined: Jul 1999
Posts: 138
Likes: 1
From: Brick New Jersey
Tom,
You hit the NAIL on the head, the first time it did this. I treated it like it was flooded so I took a screw driver and forced both primary and secondary butterfly open and kept them open for a few minutes. that's when it would start. I did install an aluminum shield I got from Holley, obviously that's not doing much good.
I would be interested what you come up with, now that I can keep it cool with the fan from my Benz. I drive it more than before, of course just avoid stop and go traffic.
You hit the NAIL on the head, the first time it did this. I treated it like it was flooded so I took a screw driver and forced both primary and secondary butterfly open and kept them open for a few minutes. that's when it would start. I did install an aluminum shield I got from Holley, obviously that's not doing much good.
I would be interested what you come up with, now that I can keep it cool with the fan from my Benz. I drive it more than before, of course just avoid stop and go traffic.
Last edited by tomdoc; May 20, 2015 at 10:15 PM.
Thread Starter
Burning Brakes
Joined: Sep 2010
Posts: 799
Likes: 26
From: Lexington Park Maryland
Try this heat shield from " hotrodcarbs.com " I am ordering the tripower carb insulators today. These are more then just a piece of light aluminum. They are 1/4" to 1/2" Material. I checked for hood clearance on my tripower air cleaner buy putting PlayDough on all three corners of the triangular air cleaner and in the middle on the air cleaner bolt. Shut the hood. When opening the hood I measured how much the PlayDough was squashed. I had more the the 1/2" I need. I clear it by more then a 1". Tom.
