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I've been reading about overheating and air flow problems and noted that someone mentioned carbuereter adjustment and timing as a possible cause of overheating.
I have a 55 with new performance 350 crate engine. It has an old model VA a/c system which seems to work well, but she will overheat at idle on a hot 100+ day, doing fine at around 180 degrees at highway speeds. I have the 6-bladed 18" fan with a shroud, and think I have plenty of air flow. However, I am considering adding a couple of 10 to 14 inch fans mounted in the grill area blowing on the condenser and radiator. But, I'm concerned about blocking the air flow at highway speeds. I could use some advice on this matter.
But about that business of carbuereter adjustment and timing. My ignition timing was set at the recommended setting when the engine was installed, however, my Edelbrock 4-barrel is a little funky. I've played with the adjustments, but I'm not sure they are right. It idles ok, until it heats up. I do know one thing...... she loves gasoline. She has a 700:R4 four speed automatic, and shifts into overdrive at about 42 MPH, putting the tach at around 1800 RPM at 60 MPH. But, I figure I'm getting somewhere between 10 to 12 miles per gallon, at most. I think maybe I need to visit the carbueretor adjustment man...... if I can find one.
Appreciate comments.

Gene
 

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I seriously doubt it's the carb.

I would be looking at the timing. Do you have a vacuum advance unit? If so is it connected to full manifold vacuum?

Do you have a factory fan, or at least a factory style fan? What is the relationship of the fan to the shroud (fully inside, half in/half out, fully outside)?

Which "crate engine" is it? Camshaft?
 

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rebuilt engines
I've been reading about overheating and air flow problems and noted that someone mentioned carbuereter adjustment and timing as a possible cause of overheating.
I have a 55 with new performance 350 crate engine. It has an old model VA a/c system which seems to work well, but she will overheat at idle on a hot 100+ day, doing fine at around 180 degrees at highway speeds. I have the 6-bladed 18" fan with a shroud, and think I have plenty of air flow. However, I am considering adding a couple of 10 to 14 inch fans mounted in the grill area blowing on the condenser and radiator. But, I'm concerned about blocking the air flow at highway speeds. I could use some advice on this matter.
But about that business of carbuereter adjustment and timing. My ignition timing was set at the recommended setting when the engine was installed, however, my Edelbrock 4-barrel is a little funky. I've played with the adjustments, but I'm not sure they are right. It idles ok, until it heats up. I do know one thing...... she loves gasoline. She has a 700:R4 four speed automatic, and shifts into overdrive at about 42 MPH, putting the tach at around 1800 RPM at 60 MPH. But, I figure I'm getting somewhere between 10 to 12 miles per gallon, at most. I think maybe I need to visit the rebuilt engines carbueretor adjustment man...... if I can find one.
Appreciate comments.

Gene
I think that is the good idea that you will do. Good Luck in finding. :D
 

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How many miles on the New Crate engine? Lots of drag on the rings until they seat and the motor breaks in. My newly rebuilt motor ran hot just as yours does and so I called the builder. He asked how many miles and I told him about 300. He said call me back if it's still running hot after 1000 miles. I hit about 900 miles and the temps came down. Haven't spoken to the engine builder since :D

Don
 

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I also doubt your overheating problem Is caused by your carb mixture/timing. Excess fuel, actually has a cooling effect, although its a pretty expensive way to cool.

Actually, Im not supriised that it overheats at idle on a 100+ degree day. Thats a pretty extreme environment. Way back when, they added a fast idle knob for that exact reason.

Not to say you can't overcome the problem. You didn;t mention what kind, how big, or how old your radiator is. I see alot of installations where the builder leaves off the shrouds below the radiator support. These are necessary unless you add a full fan shroud. I also see quite a few where the fan is not close enough to the radiator. It should be 3/4 to 1 inch from the radiator. The no brainer fix is to add electric fans. but I think a bigger/better radiator with proper shrouding is a better answer.

I personally have seen how much more heat a new engiine produces, over a well broken in engine, in a 76 ford pickup I had way back when.

I won't go into the gory details, but the end result was that the old radiator, even after it was boiled out, would not cool the engine, but a new radiator took care of the problem. A new "desert" radiator of some kind might be the fix. Just my .o2
 

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I've been reading about overheating and air flow problems and noted that someone mentioned carbuereter adjustment and timing as a possible cause of overheating.
I have a 55 with new performance 350 crate engine. It has an old model VA a/c system which seems to work well, but she will overheat at idle on a hot 100+ day, doing fine at around 180 degrees at highway speeds. I have the 6-bladed 18" fan with a shroud, and think I have plenty of air flow. However, I am considering adding a couple of 10 to 14 inch fans mounted in the grill area blowing on the condenser and radiator. But, I'm concerned about blocking the air flow at highway speeds. I could use some advice on this matter.
But about that business of carbuereter adjustment and timing. My ignition timing was set at the recommended setting when the engine was installed, however, my Edelbrock 4-barrel is a little funky. I've played with the adjustments, but I'm not sure they are right. It idles ok, until it heats up. I do know one thing...... she loves gasoline. She has a 700:R4 four speed automatic, and shifts into overdrive at about 42 MPH, putting the tach at around 1800 RPM at 60 MPH. But, I figure I'm getting somewhere between 10 to 12 miles per gallon, at most. I think maybe I need to visit the carbueretor adjustment man...... if I can find one.
Appreciate comments.

Gene
On the carb problem you want to check the float level and the fuel pressure first edelbrocks need fairly low pressure to operate correctly.

Also I had the same problem when my car gets hot in the summer the idle would get richer and richer at high temps and the engine would start sputtering and the idle speed would drop. I put a wide band 0-2 sensor and gauge on it and the afr numbers confirmed it it would go from about 12.5 to 1 down to 9.8 to 1 on a hot day. What I suspect is that when it was hot the fuel in the carb bowls begins to boil/vaporize. I solved my problem by converting to tbi fuel injection.
A carb insulator spacer can help but the problem may be more related to re-formulated gasoline.
Since the carb vents to the air horn area the vapors get added to the fuel/air mix the carb normally supplies and it gets richer.
Lastly you may need to change the rods/jets and springs to adjust the carb to what your engine needs to get your mpg up . Its pretty easy to do the rods/springs
edelbrock has a tutorial in the owners manual

http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

Regards, Robert
 
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