Just bought a 1968 Ford N850 single axle dump truck. Has a 401 gas motor in it with air brakes all around. I'm tryin to rewire the whole truck because the harness got unhooked and apparently the fan got ahold of it. My question is: the radiator has what seem to be spring loaded louvers on the front of it that are stuck open. I need to know if they are air operated or vacuum or cable or etc. I'd like to be able to open or close them according to the weather conditions. Plus it's cool to see on a vehicle that is 17 years older than I am. Any help would be greatly appreciated....

 

The shullers themselves were the same part number (C1TZ8475D) for air or vacuum. Since your truck has airbrakes then the controls for the shutters are also air.

 

Yeah I had an older gentleman that had an N-700 with hydraulic brakes tell me the same thing. How do they activate though? I can't find a valve or actuator or anything else to open or close em. They are open which is a plus but they've got to be able to close as there is a rubber lip at the top of each shutter that runs the length of em which tells me they should seal. I just don't want to tear the whole thing apart just to find that the switch was right in front of my face the whole time....kind of frustrating.

 

They should be connected to a thermostat/temp sending unit. Open for airflow when warm, closed below a given temp for performance and mpg. Sorry I can't pinpoint that for you.

 

I will do some checkin. This cold snap in Va.should show em if they're like that though. Thanks.

 

Ozarktraveler is right. although I don't know about the N series much but if they have the flaps in front of the radiator they should be controlled by a thermostat of some sort. That's how my old REO is.

 

FYI the shutters are spring loaded open. It takes either a air cylinder or vacuum cylinder to actuate and shut them. That cylinder is off to the drivers side of the radiator.


The actual thermostat to control said cylinder is on the upper heater hose, also on the drivers side. Right in front of the air cleaner, and sorta beside the upper radiator hose.


There is a hose from the air system or going to the intake manifold (vacuum) to the thermostat and then from the thermostat to the air or vacuum cylinder.


Both cylinder types are single action and just pull against the spring tension to close the shutters.


Probably long disconnected though as since they were spring loaded to fail open, that means that most people just do not fix them as they were not critical in most of the continental US as the temps just are not that low.


David

 

I saw that wire/cable on the radiator and it looks out of place. The sending unit for the temp gage is on the top of the intake manifold beside the carb on passenger side of engine. Yeah they're definitely spring loaded. I'm gonna do a lil investigating and see if I can bypass the thermal control and just run air to the actuator for open or close. If I can't with the stock stuff my buddy has a couple air cylinders for conveyors that will work if I just unhook the old actuator. Thank you for the insight. If I remember when I go to my parent's house I will post some pics of the ol girl. Guy I bought it off of said it was missing due to a leaking exhaust manifold.... Found a plug wire off a spark plug yesterday and stuck it back on and she purrs like a kitten!!!!

 

I saw that wire/cable on the radiator and it looks out of place. The sending unit for the temp gage is on the top of the intake manifold beside the carb on passenger side of engine. Yeah they're definitely spring loaded. I'm gonna do a lil investigating and see if I can bypass the thermal control and just run air to the actuator for open or close. If I can't with the stock stuff my buddy has a couple air cylinders for conveyors that will work if I just unhook the old actuator. Thank you for the insight. If I remember when I go to my parent's house I will post some pics of the ol girl. Guy I bought it off of said it was missing due to a leaking exhaust manifold.... Found a plug wire off a spark plug yesterday and stuck it back on and she purrs like a kitten!!!!

 

You should see a tall thing screwed into the intake manifold water jacket
usually near the thermostat, thats called the shutter stat. It will have 2 pipes
or high press hoses. Some where you should find (by following the plumbing)
a reservoir that is filled with shutter fluid (marvel mystery oil same thing).
On this reservoir there will be a shut off valve to disable. Most were disabled
during the summer and probably forgotton. We had those which were on
all our T950s, We also disabled them while plowing= snow and ice they
would freeze closed. Google Kysor Shutter Systems = they were used by
all truck and bus mfg.s .. The usual plumbing=air goes into the shutter stat
when 'satisfied' air goes to the reservoir picking up oil then to the shutter
cylinder. The cylinder is no more that a leather cup that needs that filtered
air & oil to keep it soft. Engine temp rises to a preset value air is applied
to shutter engine temp cools shutter stat exhaust's the air, shutter opens.
Note there is a little cover on the shutter stat & and in there is a star wheel
(like a brake adjuster) clockwise to increase temp ccw to decrease. Also
there is only a small "window" of its action like 175 to 180 degrees.

parts are available (I have new cups) by the way this explanation was on our 534's same as a 401 as far as description goes





sam

 

Super helpful. I figured somebody would know. Haven't had much of a chance to work on the truck past few days but atleast now I know what to look for. I just think it's crazy that they had that kind of technology on a big truck in the sixties and nowadays the car manufacturers make a big deal out of everything they "create".

 

Interesting, both of the late 60's T850/950 Super Duty have had standard air cylinder, no oil just air. That is perhaps something on the older shutter systems.


My 1970 service manual, at least on the air system shows no oil used either, just compressed air.


David

 

Not crazy- nothing new -goes back to early 1940's..

 

Even into the 1930's like I said my REO sedan has this type of setup on it.

 

Thermostatically controlled radiator shutters were standard equipment on 1932/39 Packard Super 8's and V12's.

The Packard's vertical grille bars themselves opened or closed, there were no add-on shutters. I assume your REO has the same setup.