641 Cooling system

This past weekend I installed a new water pump, hoses, and thermostat. Found out when I took the tractor back for running hot they obviously pulled the thermostat out as I installed the 160* thermostat and found out that just using the shreader running the engine at 1200 rpm resulted in 210 to 225* temps.

As of now I ordered a radiator from "external_link" as it was the only one I found that did not require modification to the original fan shrould due to their relocation of the drain petcock.

I will see what quality it is when it comes in but I know this engine shouldn't be running this hot and I believe the culprit has to be the original radiator is stopped up and is not cooling.

I could understand 180* temps holding steady with 90* ambient air temp but anything over 200* is just screaming something isn't right. Might have to look at timing as well after this as well.

Now to get to it, what has to be removed to get to the radiator? All of the sheet metal or can I remove just bits and pieces.

Before you spend all that time and money try this. Drain the cooling system. Next fill it with vinegar and run it a few times. Then drain it and rig up a hook up to run a garden hose into the block drain. Then flush it out with the hose for say 2 hours. Then run it and see if that helps. My Oliver 77 would run hot but once I did the vinegar flush and back flush it has NEVER run hot since

Addressed the same issue on my 641 in July, would build heat running a
rotary cutter. Felt good about the cooling system, radiator seemed good,
thermostat good, belt snug, cooling system would not keep up. I ran across a
"parts box bargain" which had a new water pump that was a bolt on pulley
rather than the pressed on that was on the tractor. Key thing is the pressed
on has a 3 blade fan, bolt on has 4. Asked about finding the
pulley/spacer/fan parts here and they arrived just a few days later, price
for the parts was very fair. ALL of my temperature problems left the machine
with the 3 blade fan.

I am not too sure of this cooling system. There were quite a few problems with this tractor when it was purchased and I fixed a bunch of the rigging the tractor lot I bought it from did.

Their fix for a leaking lifter cover was to run a bead of red RTV silicone across the top edge to stop the leak temporarily. Their fix for the cooling system problem was throw on a new belt as the old was stretched too far and remove the thermostat and even then on a warm day without the thermostat it would run up around 190 to 200 with ambient air temps of 100.

I put a new water pump on as they claimed the 60 yo original water pump that had 1" of side to side thrust play was "normal" which I called BS on, I put a 160* thermostat in as well as I wasn't sure if they had a 160 or a 180 in it due to running 190 to 200. I also replaced the radiator hoses and the air flow at idle is tremendous with the 4 blade fan. I know its not a air flow problem but is a problem with cooling capacity as if you let the tractor sit 10 minutes after it was up at 225* you crank it up it will be around 180*. This tells me something is up and the only thing left is the 60 year old original radiator.

Only thing is I am going to hate pulling the whole clip just to do a radiator job as I planned on pulling it when it came time to strip the tractor, prime, and paint it to make it look right.

~Update~
I have to say I don't mean to step on toes or to have my post sound like I am shooting down peoples ideas. Just trying to get as much information down and theres a possibility of it being taken the wrong way.

I do appreciate the responses though. I know while back when I first had this over heating problem before the shop bandaided it by removing the thermostat I was told these tractors being worked even with a 160* thermostat would run around 180 to 190 and even as high as 210. I honestly don't see how that can be because I work on cars and trucks for a living and if you have the engine running at 1200rpm that means the waterpump is moving more water and the fan is pulling more air it shoudnt slowly get hotter it should hold a steady temp all day long. I have replaced a few radiators that were plugged up that would over heat when you held the rpms up and its the last part on this tractor that is not new.

I also just caught you were saying to go with a 4 blade fan, Mine is equipped with a 4 blade fan from the get go and the original water pump which the pulley was riveted on which tells me its 1958 Ford Vintage had the fan bolted onto it via 4 screws.