The Ford Barn

spinelll · 05-27-2025, 06:04 AM

My ’30 Roadster overheated yesterday during a slow-moving Memorial Day parade in northern NJ (Outside Temp upper 60’s).
Later, I realized that I was running with my timing fully retarded.
Did that contribute to my issue?

Thanks
Leo

ronn · 05-27-2025, 06:13 AM

the timing was your issue.

Fullraceflathead · 05-27-2025, 06:25 AM

Yes running with the timing retarded will definitely cause overheating I also feel that that's 1 of the reasons why the exhaust manifolds warp because people sometimes will forget to advance that timing.

nkaminar · 05-27-2025, 06:57 AM

It also helps to run the GAV a little richer. Some brass cars, pre 1915, will install a second radiator under the car with an electric fan for parades.

BButturff · 05-27-2025, 11:14 AM

There's no question that running late ignition timing causes overheating. If you were able to see into your exhaust manifold during this you would see fuel burning inside the exhaust manifold instead of the combustion chamber. In fact, I have seen Model A exhaust manifolds glowing bright cherry red in the daylight because of this. That's around 1000+ degrees F!

Chuck Sea/Tac · 05-27-2025, 01:25 PM

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This is an older picture of retarded spark

ThirstyThirty · 05-27-2025, 01:44 PM

Quote:

Originally Posted by spinelll

My ’30 Roadster overheated yesterday during a slow-moving Memorial Day parade in northern NJ (Outside Temp upper 60’s).
Later, I realized that I was running with my timing fully retarded.
Did that contribute to my issue? Thanks Leo

hi, do you know how the timing got retarted? since your car is a '30 A roadster... holds interest to me.

even though all A's time the same as I can best remember...

gdmn852 · 05-27-2025, 02:23 PM

Hello, probably forgot to advance it , If you haven’t driven a Model A for awhile, forget to do that, along with turning on the gas valve!

Gene F · 05-27-2025, 03:20 PM

Start the car up in the driveway. Open the GAV about 1/8 turn. Let the car idle after it warms up. The ignition advance should be down lets say 3/4. It should run for one-half-hour without overheating.

If it overheats you have more work to do. If it does not overheat the spark advance setting was the issue.

spinelll · 05-31-2025, 10:37 AM

Thank you for all of the quick responses.
I've been driving in parades for 15+ years. Not sure why I set the spark like that this time.

I'm curious; How does a retarded spark lead to overheating?

nkaminar · 05-31-2025, 03:21 PM

An advanced spark enhances combustion so that more of the heat goes into moving the pistons. So an advanced spark means lower temperature in the combustion chamber. When the spark is retarded the combustion is not efficient and the combustion is hotter. Plus, the combustion is still going on when the exhaust valve opens and the hot combustion is taking place in the exhaust manifold and exhaust system.

Related to this is a higher compression head. Besides more power, the higher compression head increases the efficiency of combustion and at the same road speed the engine temperature is lowered.

stevemclark · 06-02-2025, 04:47 PM

On the steering column it's the lever on the left side ,up to retard spark and start,down to run.

05-27-2025, 06:04 AM	#1
spinelll Senior Member Join Date: May 2010 Location: Northern New Jersey Posts: 352	Parade Overheating My ’30 Roadster overheated yesterday during a slow-moving Memorial Day parade in northern NJ (Outside Temp upper 60’s). Later, I realized that I was running with my timing fully retarded. Did that contribute to my issue? Thanks Leo

05-27-2025, 06:13 AM	#2
ronn Senior Member Join Date: Feb 2011 Location: NNNNNNNNJJJJJJJJJJ Posts: 7,650	Re: Parade Overheating the timing was your issue.

05-27-2025, 06:25 AM	#3
Fullraceflathead Senior Member Join Date: May 2012 Location: Chillicothe, Missouri Posts: 1,684	Re: Parade Overheating Yes running with the timing retarded will definitely cause overheating I also feel that that's 1 of the reasons why the exhaust manifolds warp because people sometimes will forget to advance that timing. __________________ "If I asked people what they wanted they would have said faster horses." -Henry Ford "Primitive technology is not a design flaw" 1928 Ford Model A Roadster Pickup 1930 Gordon Smith Air Compressor 1941 Willy's Pickup 1960 Thunderbird-For Sale 1964 Buick Riviera 2x4 425 1965 Pontiac GTO, 455 Super Duty 2004 Dodge Ram SRT-10, V-10 Viper 1977 Charger Jet Boat,460 Ford,Jacuzzi Jet Front Engine Nostalgia Dragster,Supercharged 296 "Fullrace Flathead" Ford Engine Build up on DVD ask

05-27-2025, 06:57 AM	#4
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 5,872	Re: Parade Overheating It also helps to run the GAV a little richer. Some brass cars, pre 1915, will install a second radiator under the car with an electric fan for parades. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.

05-27-2025, 11:14 AM	#5
BButturff Senior Member Join Date: Oct 2024 Location: The driftless area of SE Minnesota Posts: 116	Re: Parade Overheating There's no question that running late ignition timing causes overheating. If you were able to see into your exhaust manifold during this you would see fuel burning inside the exhaust manifold instead of the combustion chamber. In fact, I have seen Model A exhaust manifolds glowing bright cherry red in the daylight because of this. That's around 1000+ degrees F! __________________ _______________________ The other Bruce in Minnesota 1931 Model A Closed Cab (Budd) Pickup "Aurora" Model A Ford Club of America Lady Slipper A's

05-27-2025, 02:23 PM	#8
gdmn852 Senior Member Join Date: Feb 2019 Location: Erie Pa Posts: 962	Re: Parade Overheating Hello, probably forgot to advance it , If you haven’t driven a Model A for awhile, forget to do that, along with turning on the gas valve!

05-27-2025, 03:20 PM	#9
Gene F Senior Member Join Date: Mar 2012 Location: Ohio Posts: 2,476	Re: Parade Overheating Start the car up in the driveway. Open the GAV about 1/8 turn. Let the car idle after it warms up. The ignition advance should be down lets say 3/4. It should run for one-half-hour without overheating. If it overheats you have more work to do. If it does not overheat the spark advance setting was the issue.

05-31-2025, 10:37 AM	#10
spinelll Senior Member Join Date: May 2010 Location: Northern New Jersey Posts: 352	Re: Parade Overheating Thank you for all of the quick responses. I've been driving in parades for 15+ years. Not sure why I set the spark like that this time. I'm curious; How does a retarded spark lead to overheating?

05-31-2025, 03:21 PM	#11
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 5,872	Re: Parade Overheating An advanced spark enhances combustion so that more of the heat goes into moving the pistons. So an advanced spark means lower temperature in the combustion chamber. When the spark is retarded the combustion is not efficient and the combustion is hotter. Plus, the combustion is still going on when the exhaust valve opens and the hot combustion is taking place in the exhaust manifold and exhaust system. Related to this is a higher compression head. Besides more power, the higher compression head increases the efficiency of combustion and at the same road speed the engine temperature is lowered. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. Last edited by nkaminar; 05-31-2025 at 03:29 PM.

06-02-2025, 04:47 PM	#12
stevemclark Senior Member Join Date: Oct 2019 Location: Central Shenandoah Valley,Waynesboro,Va. Posts: 147	Re: Parade Overheating On the steering column it's the lever on the left side ,up to retard spark and start,down to run. __________________ It's not the destination ,it's the journey .