Overheating: How hot is too hot?

[62Ranchero200]

Greetings Ford Six Fans:

Stock mechanical fan, no fan shroud, new stock type radiator, new water pump, Houston traffic. If I'm forced to sit at a light for a long time, water temperature creeps up towards 220. I know that some engines have 195 degree thermostats, so I'm guessing 210 or so is perfectly fine. For a 200, how hot is too hot in the sense of risking damage to the engine?

Notes: According to the Ford service manual, a 13-15 psi radiator cap is called for, but previous owner had a 7 psi cap on ... have ordered a replacement cap from Dearborn Classics, but not received yet. I just installed a very nice Autometer water temperature gauge, so I'm quite sure my temp indications are correct.

Thanks
Bob the Builder

 

[bubba22349]

fan shroud would be a help sitting at a light if you have a 4 blade fan maybe you can also find a 5 blade it would help too.

 

[MPGmustang]

fan shroud and a 6 blade fan will cure traffic heat. I get that hot with my ac on high and I don't have a fan shroud yet...

 

[rbohm]

8) 220 is about as high as you want to go. you dont really get into engine damage though until the temp gets closer to 230-235 sustained. i would go with either a 5 blade fan, or an add on supplemental electric fan, it doesnt have to be a big one though, something around 2000 cfm max flow from the fan would be best, but 1400cfm would do nicely also, as long as oyu keep the stock mechanical fan as well.

 

[MustangSix]

Too hot is when:
A. Fuel begins to boil;
B. Oil gets too thin to lubricate stuff;
C. Engine parts begin melting;
D. Electronics cook and fail;
E. Coolant boils off.

Generally, with good synthetic oil, a modern EFI engine can not only survive, but run for a long while at nearly 300 degrees. On carbureted engines, if you have good oil, a short exposure to 220-230 won't hurt anything, but likely won't run well.

 

[CobraSix]

Consider a 180* T stat.

 

[oldgrezmonke]

Try the correct radiator cap first . Each pound of pressure raises the cooling capacity by about 3* . Edit , my math was off - The 13 lb. cap adds 6 lbs. - 6 x 3* = 18* possible more capacity which could bring that 220* in traffic down to 199* .

 

[62Ranchero200]

Try the correct radiator cap first . Each pound of pressure raises the cooling capacity by about 3* . The 13 lb. cap adds 8 lbs. - 8 x 3* = 24* possible more capacity which could bring that 220* in traffic down to 196* .

The correct 13 psi cap should arrive today or tomorrow, and I also ordered a six blade nylon fan from Summit Racing (fan clearance is limited, so I went that route rather than the wide blade aluminum fan).

Probably won't get the fan tomorrow, and because of eye surgery won't be able to work on the car for at least a week.

Thanks
Bob

 

[oldgrezmonke]

Don't take any chances with you eyes . I just noticed my math was off and edited above . I have thought about one of the nylon fans but they are supposed to be 2" deep so you need a spacer . My figures show my combination of parts would need a 7/8" spacer which it seems no one makes nor even 1/4" or 3/4" which I could make work with some shims . What were your measurements ? I have about 2 3/4" from the core to the crankshaft bolt and about 1 3/4" to the water pump pulley with the radiator I have now .

 

[62Ranchero200]

Don't take any chances with you eyes . I just noticed my math was off and edited above . I have thought about one of the nylon fans but they are supposed to be 2" deep so you need a spacer . My figures show my combination of parts would need a 7/8" spacer which it seems no one makes nor even 1/4" or 3/4" which I could make work with some shims . What were your measurements ? I have about 2 3/4" from the core to the crankshaft bolt and about 1 3/4" to the water pump pulley with the radiator I have now .

The Flex-A-Lite nylon fan I ordered from Summit Racing (a 16" diameter, 2" deep, clockwise rotation) has arrived and I will install it as soon as my doctor releases me to work on the Ranchero again.

The fan I have currently seems like a stock, four blade steel fan that has been chromed. As installed currently, I have about 1" from the front of the fan to the radiator core and about 1/2" from the back of the fan to the 2-V crankshaft pulley. When I replaced the 1-V balancer / pulley with a 2-V on the engine rebuild, there wasn't enough clearance between the fan and the pulley, so I added a 1/2" spacer. I'm hoping I'll have enough clearance now, but if not I'll either add shims or a slightly wider spacer. My tightest clearance is between the bottom of the fan blades (towards the ground) and the bottom radiator tank. It's probably only 1/4", but that shouldn't be a problem since the nylon fan is the same diameter as the existing steel one.

On another subject ... I know coolant / water mixture is a compromise between cooling in the summer, antifreeze in the winter, and discouraging rust. Here in Houston, Texas, with the Ranchero in a garage, antifreeze protection is almost a non-existent issue. During the summer (May - September in Houston) with 100 degree plus ambient temperatures and heavy traffic, cooling is my overwhelming priority. What's the best coolant / water mixture for cooling? I've been aiming for 50% so far.

Thanks for all your help,
Bob the Builder

 

[62Ranchero200]

Installed the six blade flex fan yesterday.

In the process, took my first really close look at engine vs.radiator placement, with detailed measurements. The fan (and thus, the engine) is not centered with the radiator either horizontally or vertically. So, if I wanted to make a fan shroud, the hole for the fan would not be in the center of the shroud. Maybe this is due to the fact that a 1980 engine was swapped into my 1962 Ranchero, and the mounting geometry is slightly different for the later model engine.

The engine also sits slightly higher in the front, with the result that the lower blades of the fan are closer to the radiator core than the upper blades of the fan. Is this normal for a small six?

The largest problem was that while the stock type fan had about half of it's depth in front of the mounting plane (where it bolts to the water pump pulley, or in my case a spacer) and half of it's depth behind the mounting plane, the Flex-A-Lite nylon fan has almost all of it's depth behind the mounting plane, so it would have hit my 2-V crankshaft pulley without more spacing. The spacing requirement changed from 1/2" to 1 3/8".

I realize now that a two-core radiator is not enough for a 200 in Houston summer traffic, even without air conditioning. I ordered a three-core from Dearborn Classics, but I'm going to have to cut the core support to make room for it. Will post pics of the project before I drop the new radiator in.

Bob the Builder

 

[bubba22349]

Have you checked the condition of the motor mounts especially the trans mount if they are real old and have settled might be why the fan blades are angled so much.

 

[62Ranchero200]

Have you checked the condition of the motor mounts especially the trans mount if they are real old and have settled might be why the fan blades are angled so much.

From your reply, I gather than the small six nominally sits level from front to back in the engine compartment?

When the 200 and C-4 were swapped in, replacing the 170 and 3 "on the tree", someone made a custom trans mount - at least it looks homemade to me, although the workmanship is rather good. It could very well be that the trans sits a bit too low because of the custom mount. If so, maybe I can shim it up somehow and level the engine out. Thanks for pointing me in this direction.

Bob

 

[MPGmustang]

Have you checked the condition of the motor mounts especially the trans mount if they are real old and have settled might be why the fan blades are angled so much.

From your reply, I gather than the small six nominally sits level from front to back in the engine compartment?

Actually, the engine is supposed to sit un-level, the carb mounts 15* from the engine and that's supposed to be level or very close to level. so if you want to check if it's acurate then level the carb not the log/head/block.

to make some extra room, I took a 4bls hammer to the radiator support, can barely tell I moved it but pushed the mounting holes forward almost 1 inch. and I didn't have any issues with my AC condencer fitting. now I took the entire front grill of to do the work, took me 45mins to take the grill of but probably saved me $$$ if I missed my target with that hammer.

the fan is correct to sit closer to the bottom than the top.