226 G straight 6 overheating

edhd58

edhd58

Well-known member
My 226 g is having an overheat issue. It happens when setting still and idling. Cools back down when moving, and engine speed is up. Took it out for a drive today, 90 degree day, all was fine when moving but as soon as I let it idle the temp would start rising. I hadn't had it out enough till now to notice this problem.

What i have is,

Recent rebuild, less that 250 miles, machine shop didn't acid dip the block they baked it.
New rebuilt water pump, with new style helical fins, not the straight original type Ford pump
NORS radiator - new not rebuilt -- 0 lb cap
Belts are tight - do not squeal if engine is revved hard


If I put a fan in front of the car, idling it will cool down.

Any suggestions?

In the pics it has cooled back down, it had reached 210 on the mechanical gauge, the dash gauge is not hooked up
 

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You have already figured out that there is not enough air through it when not moving. I don't know what the spec is for the distance of the fan to the radiator, but closer is better. Other options are more blades on the fan, or a shroud.
 
Wow, I had one of those in my 47 coupe and it wouldn't run hot enough. I had to place a restrictor inside the top radiator hose . You mentioned the impeller had been changed in the water pump. Are you absolutely sure the helical fins are cut to run in the direction of the pump? Also run a 7 lb cap. Those engines just don't have a history of running hot, at least none that I've ever experienced.
 
Also make sure that you have all the deflector shields in place around the grill opening and the radiator support, including the one on the top so that all air being drawn in through the grill opening is being drawn through the radiator and not going around it.
 
I just happened to think, I have a modern type thermostat in it. will that cause any issues??
Shrouds crossed my mind, and will be easy enuf to make. I don't have the bottom air shield on it btu I think that would only affect air flow at speed.
There sure is a lot of radiator the fan doesn't cover, (just a thot going thru my thick skull).
Kinda has me wondering if the NORS radiator (had old old masking tape over all the holes) might not be truly NEW ORS and may have a flow problem. There is a lot of water movement from the pump so I think the pump may be doing its job well enough.

Oh well, just random thoughts, I am going to talk to my welder neighbor and get some thin sheet metal and see about having him make me a shroud.
 
I am running a modern style 180* in my H with no overheating issues. It gets to 180 and stays there. It controls the flow beautifully to maintain the temp dead on. After it warms up anytime I check it with an infrared thermometer at the top of the radiator is is consistent.

jb
 
If a radiator cools at speed, it indicates the radiator will do its job with airflow. Many radiators will cool at idle but not at speed, that is a capacity problem.
 
The one test that you've done that solves the problem is adding airflow. It sounds like your car is missing baffles...those should be replaced. The engineers put those there for a reason. Did the car originally have a fan shroud? If so, replace that as well. If you don't care about originality, an electric fan works well...I hear.
 
I'm not as concerned with looks as I am the heat issue. So a shroud is a definite possibility. Any one have one on a 6 they could shoot a pic of to give me a head start?
All the parts are in place with the exception of the one at the behind the grille and in front of the radiator.
I am also looking at adding a spacer between the fan pulley and fan to get it about an inch closer to the radiator. That will still give about an inch clearance.
 
optimum distance between a fan and radiator without a shroud is 3/4 of an inch. if you have a fan shroud, the fan blades should extend only about halfway into the shroud opening. anything other than this will not result in maximum cooling. you may also want to check different sections of your radiator with an infrared heat gun for "cold" spots that may indicate that the radiator is partially plugged. this will cause low speed/idle overheating, but may be ok at speed. note that the bottom of the radiator should be cooler than the top, as the pumps pull the coolant up and into the block and "push" it out the top outlets back into the radiator. unless my mind is thinking backwards. hope that this will help
 
well the overheat issue has never gone away, but then i havent done much to address the issue.
I did today fashion a quick shroud out of cardboard and taped it in place. The darn thing worked wonders.
In the next few days I will be making a shroud that surrounds the entire fan, this one only encloses half the fan.
I let the car idle for about an hour and it never got over 192.
The radiator is just barely 3/4 inch from the fan and I can definitely feel a lot more air flow with this piece of crap shroud, I can only imagine what a nice complete shroud will do.
I'll post pics of the completed shroud, for now here's something to laugh about.

Oh yeah, if anyone has a modern fan belt number and maker for this thing I'd love to have it. I can NOT find one anywhere that is the correct size. All I can find is 1/2 inch wide, it needs to be 3/4 wide.
 

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You can use the 1/2 inch or slightly larger.. as long as it doesn't sink to low.. When I switched to an alternator.. I could not find any belt that matched.. Ended up using one belt from Granger and one from Gates..
 
51 MERC - the shroud material is free, but i have definitely thought of using a more blade fan. I hadnt looked yet to see whats available.

Vintage Cooper - i have a 1/2 inch wide belt that seems to slip no matter how tight I get it. it may just be me. I think I found a 5/8 wide belt @ NAPA. We'll see, it's in Phoenix and I'm in KY. It's supposed to be on its way.
 
When I first got my '51 sedan with a 226 on the road I did not have a front bumper splash pan installed. The car would overheat the minute I stopped moving. After installing the splash pan, the problem went away. Apparently the sixes are very sensitive to air flow.
 
I just finished working on a little G series the other week. It was overheating as well. They are a bit sensitive to ignition timing and you may wish to be sure your advance weights in your dizzy are not stuck.


IMG_1272.jpg
 
35fordtn. I see it had the correct belts on the one you worked o.k. have any idea where they came from?????
I have the timing set center on the distributor i have no Mark on the harmonic balancer to go by.
 
edhd58 said:
35fordtn. I see it had the correct belts on the one you worked o.k. have any idea where they came from?????
I have the timing set center on the distributor i have no Mark on the harmonic balancer to go by.
Click to expand...

Very little timing to do.. EdHD58.. that is a beautiful motor
 
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