1953 NAA Overheating?

My tractor runs hot up to 250 degrees during the summertime (90 degrees) when I am brush hogging using a heavy 5 foot rotary cutter. I have
put a new radiator, water pump, thermostat (160 installed properly), adjusted the fan belt to the 1/2" slack spec. I am preparing to flush it
out and paid attention to how much coolant was required. Was very surprised to find the spec to be 15 quarts!! I have owned this tractor for
10 years and it never took more than 8 quarts. Never thought anything about it because that is all my trucks and cars took. Well, my mistake
for sure. Now what is the best way to flush out 7 quarts of sediment?

Thanks in advance to any and all replies and I now have enough experience with my tractor to help others out.
 
For now you can use the products at your local auto parts store and see how much comes out of each flushing. Make sure the material is properly disposed of and that kids nor pets sample the flushed material via drinking it. If after a couple of flushings you still get around 8 quarts of liquid coming out then you most likely will need to disassemble the engine and see how much build up of things such as rust and calcium (hard water) are evident. You may have to have the block and head hot tanked (cleaned).
 
Before you get carried away trying to back flush where the only equipment capable of doing a good job is no longer available, check to see if the radiator is doing its job. Check temp @ inlet and outlet - you should see 30 degrees Fahrenheit or more lower at the outlet.

If everything is OK, go to the local auto parts store and buy some 'core plugs', which are incorrectly described as "freeze plugs" of the correct sizes and remove the ones in the block and the head.

After removing them, you might be able to use some stiff wire to remove the hardened material left in the cooling passages. Remove the thermostat and use a garden hose high pressure adapter to aid in flushing the cooling passages.

After removing as much as you can, replace the core plugs with steel type plugs, EXCEPT for the lowest plug. Here install a rubber plug, fill the cooling system with water and a little 'water pump lube'. Operate the tractor as normal, then once per week, remove the rubber plug and reflush. Repeat until the water runs free of hard particles, then replace that plug with a steel. Reinstall the thermostat, add correct amount of antifreeze / water and retest.

You may have to remove the radiator and have it "rodded out" if some hard debris fills it up.
 
All the flushing in the world isn't going to get you room enough for 15 quart. Maybe 11 quarts ??
 
Are you saying you have used this heavy 5ft brush hog the same way in the past and didn't overheat? A 5ft brush hog taking a full cut in heavy brush set low, with used blades could easily overload the cooling system on an NAA this time of year.
 
My NAA always overheated when using my 5ft rotary cutter during the summertime. I could cut for an hour, then let it cool down while I cleaned the radiator. Now it is taking half that time. I had the rotary cutter gear box rebuilt and the blade sharpened this past winter. Just recently replaced the radiator and the thermostat. Now I am preparing to flush the engine. Last night I opened the engine block drain. Did not know there was a drain on the block. With a little prodding and some air pressure I got it to drain. When it stopped draining, I drained the radiator. May have drained 12 or more quarts. Gonna flush her out today or tomorrow. You are right, the heavy 5' bushhog in tail grass set low in the summer is a little too much for the old girl.
 
Opened the block drain for the first time since I owned my tractor. Took some prodding and air pressure and got the block to drain and then the radiator. Easily got 12 plus quarts.Things are not as bad as I thought!
 
Nice!
Opened the block drain for the first time
since I owned my tractor. Took some prodding
and air pressure and got the block to drain
and then the radiator. Easily got 12 plus
quarts.Things are not as bad as I thought!
 
Good advice! Thanks.
Opened the block drain for the first time since I owned my tractor. Took some prodding and air pressure and got the block to drain and then the radiator. Easily got 12 plus quarts.Things are not as bad as I thought!
 

Have you checked the timing and distributor's timing advance to see if it's working properly. If the timing is off or not advancing the tractor will run hot.
 
(quoted from post at 15:23:21 08/17/16) Before you get carried away trying to back flush where the only equipment capable of doing a good job is no longer available, check to see if the radiator is doing its job. Check temp @ inlet and outlet - you should see 30 degrees Fahrenheit or more lower at the outlet.

If everything is OK, go to the local auto parts store and buy some 'core plugs', which are incorrectly described as "freeze plugs" of the correct sizes and remove the ones in the block and the head.

After removing them, you might be able to use some stiff wire to remove the hardened material left in the cooling passages. Remove the thermostat and use a garden hose high pressure adapter to aid in flushing the cooling passages.

After removing as much as you can, replace the core plugs with steel type plugs, EXCEPT for the lowest plug. Here install a rubber plug, fill the cooling system with water and a little 'water pump lube'. Operate the tractor as normal, then once per week, remove the rubber plug and reflush. Repeat until the water runs free of hard particles, then replace that plug with a steel. Reinstall the thermostat, add correct amount of antifreeze / water and retest.

You may have to remove the radiator and have it "rodded out" if some hard debris fills it up.

He has a new radiator.
 
(quoted from post at 10:33:30 08/19/16) new radiator & maybe an inaccurate temperature gauge?

I second that, the first order of business is to confirm the gauge is correct. If the coolant reaches 250 and its boiling coolant out the rad that would confirm a accurate gauge. If the gauge reads 250 but no other signs of overheating I would verify the accuracy of the gauge.
 
When my gauge registers 240 my coolant is
boiling and the radiator cap starts to
release coolant. I feel the gauge and
radiator cap are working. I will flush the
engine and then assure my timing is correct.
I will post my results. Thanks!
 

Here is a suggestion in another direction. A basic part of brush hogging is watching your temperature gauge, because usually you are mowing a lot of mature grass and weeds which will give off a lot of seeds as you drive into them. These seeds will plug the radiator, it is just a matter of how long it takes. A higher clearance row crop tractor will draw fewer seeds so it will take longer. I usually mow with my 30 HP Kubota and it usually takes two hours for the temp to start to rise. Now here is the difference: with a modern tractor you just remove an access cover, and you then remove and clean a screen that is in front of your radiator, replace it, and go. You could remove the grill on your NAA and temporarily replace it with some widow screen to serve the same quick and easy purpose.
 
You are right. I made a screen that I fasten
onto the grill. It is made from dog proof
screening and is very tough. Not only will
it catch seeds, branches will not puncture
it. It certainly helps in that regard. The
down side is like all screens, it restricts
air flow. Last week while bushhoging my
tractor heat gauge started moving past 220
after only 15 minutes of work. I checked the
screen and radiator. There was very little
debris on it and cleared it. I left the
grill down with the screen attached to it.
My gauge dropped 15 degrees! Continued to
mow for another hour. Now when I started
mowing that day I raised my rotary cutter as
high as I could without restricting the
driveline and only cut with half the rotary
cutter. I have a heavy 5ft bushhog so cut
with 2 to 3 foot of it. Did not seem to
matter until I opened the grill with the
screen on it. That is what got me looking
into the coolant system. I am sure I have
some bockages that flushing the system will
help. And I question the timing. Someone in
a previous reply suggested when bushhoging
to set the front of the cutter up a little
higher then the back. I will do this as
well. I will let you all know the results
next week. Thanks for the advice.
 
"Someone in
a previous reply suggested when bushhoging
to set the front of the cutter up a little
higher then the back."
Odd, in that is bass ackwards to hog mfgr's recommendation.
 
My 641 will run around 210 cutting grass/weeds about 5-6 foot tall with ambient temps of about 90. When engine temp starts increasing I clean off the radiator.
 

Good reason for that, coolant absorbs the heat and air takes it away. His statement the belt is adjusted correctly it has a 1/2" slack don't mean chit to me, adjust it tight confirm the belt has a good grip on the crank and fan pulley. I have seen the belt banjo string tight and it still slipped on the crank are fan/water pump pulley. That starved the coolant of needed air to remove the heat just like the debre that plunged the front of the rad in your case.

The issue can be resolved with GOOD information he may have to back up and confirm his information.
 
Yesterday I removed the thermostat and filled it with fluid preparing to flush it today. It took 3 gallons. Today I drove it from my barn to the house. A 2 mile trip in slightly hilly terrain. Ran it in 4th gear most of the time. Air temperature 88 degrees. Engine temperature 190 to 220. Not bad. Gonna flush and back flush next.
 
Put a 1/4" nipple in place of block drain valve. Ran garden hose through radiator cap first. Then disconnected upper and lower radiator hose. Put a hose on nipple and flushed. Then flushed through upper radiator hose. Did that back and forth. Got spurts of black stuff mostly through block drain. Gonna let it flush for 10 more minutes. Then take her back to barn.
 

Every thing was in good condition With out a thermostat it may have never got to 160. I would have thought on your test drive 120 to 140 tops.
 
(quoted from post at 21:17:22 08/24/16)
Every thing was in good condition With out a thermostat it may have never got to 160. I would have thought on your test drive 120 to 140 tops.

I don't run a thermostat in my 134" 601. Same engine and radiator as the NAA. Finish mowing heavy wet grass (heavy enough to bog the engine) on a 95 degree day it never goes over 140. I'd agree with your numbers for a test drive, he should not be getting that hot.
 
Got a lot of stuff to out while back
flushing. Getting ready to go back to barn.
Hey John Smith8N is your 601 geared lower
than the NAA? Thanks.
 
(quoted from post at 22:34:02 08/24/16) Got a lot of stuff to out while back
flushing. Getting ready to go back to barn.
Hey John Smith8N is your 601 geared lower
than the NAA? Thanks.

4 speed trans, basically the same overall ratios as the NAA.
 
Got her back to barn. Put the thermostat in it, added 50/50 antifreeze. It took 2 gallons. Started it, let it warm up. When the temp gauge approached 190 it dropped to 160. I was able to put a 3rd gallon into her minus a quart. Let her run revved it up a couple of times while running the warmest it got was 210 and it quickly dropped to 190 where it stayed most of the time. Starting to suspect my temp gauge reads 10 to 20 degrees warm.
 

TIP THOUGH IT WON'T DO YOU ANY GOOD NOW, Jam a tooth pick into the thermo to open it up enough so you can do a fill and purge the air out of it.

Last week I battled a unusual issue the temp gauge was very active the complaint "Started cold the temp gauge goes to hot after a few miles of driving then drops to norm, the temp gauge does fluctuated during normal driving it will go from 1/4 to 3/4.

After I determined I believed the gauge and it was actuate to some extent it took me awhile to nail the culprit. I drilled a 1/8" hole in the themo, I have read about this for years but never ran across drilling a hole in it did any good. It was getting a air lock behind the themo why I don't know it had no other problems.

I had another about the end of the winter that had a very active gauge it would set a po128. No issue with it overheating I replaced the thermo no help, in the end it was a bad temp sender.



If it blowing off hot and the gauge shows hot I believe it, I don't have to waist time confirming the issue. If the gauge reads hot with no other signs of overheating even if the temp is in the 220 range I prove the gauge correct first before I move on.

The moral of the story confirm the gauge is correct. There are numerous issues that play into a heating issue and sometimes its hard to nail down. Engine Heating are no heat from the heater , low oil pressure are a poor/low brake pedal are the brake light in the dash on what would all of these have in common. I will goat head and tell ya low fluid levels that's the #1 cause and the most overlooked.
 
Thanks for the tips. I replaced the
thermostat last year. It was the original
and did not work when I bought the tractor.
I worked the tractor regardless sometimes
working it until it boiled over which did
not happen often. Always checked fluid
levels before starting. Before installing
new gauge I wrapped the cable with
electrical tape. Do you think this is
affecting my gage readings?
 
My tractor is working without overheating! Thanks for all your replies and advice. Here is what I learned: Ford NAA & Golden Jubilee
Operating tempetature - 180 to 220
Thermostat - 160
Coolant - 50/50 Green Antifreeze Drain and back flush thru block drain often. Takes 15 quarts new and 12 quarts is all I could get out of mine.
Fan belt should have no more than 1/2 inch play.

When you find your tractor is overheating:
Clean outside of radiator.
Check fluid levels.
Check fan belt.
Assure temp gauge is working.
Assure radiator cap is working.
Assure points are set properly.
Assure timing is not retarded.

Why my tractor overheated:
Fan belt loose.
Coolant low only 8 quarts before flushing.
Distributor points set at .012 should be .026.
Timing retarded (more than 8 degrees)
Gauge inaccuracy??? May be only a little.

You all helped and special thanks to Hobo, JohnSmith and Rich.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top