(800) 853-2651
SHOP NOW

Too much for the 640?

grandpa Love

grandpa Love

Well-known Member
Got a 6' Bushhog finish mower.
Sure makes the 640 work hard. Is
it too big for the tractor? Poor
thing , my wife had it pushing
water out over flow.
a277768.jpg

a277769.jpg
 
I had a 6ft kubota finish mower behind a Ferguson to30 and it ran it with ease I think you have a radiator problem bad water pump maybe
 
i run a 6 footer with a jubilee, i dont have any problems with it, either the radiator it too full, the cap isnt good or your taking to big a bite in tall grass
 
I run a 6 foot finish with my Jubilee, no problems. How high was the grass she mowed?
joe
 
Nice thick grass! Lots of rain in Alabama last 10 days. Wife says she had to keep lifting the mower. Water was just below fins in radiator after it cooled off. But the vent on top of cap was up, not sure if that makes a difference. No thermostat in tractor ( it came without). Gauge doesn't move because of that. Maybe should get a thermostat?
 
Radiator to full?? what's the temp gauge reading?? If it is in fact running hot not just over filled radiator then maybe time for new thermostat
 
At this point the wheels are sorta stuck. We got em loosened up enough that they swivel but they don't float up and down much. It sat for over 5 years. We had to replace 3 pulleys. Friend of ours said try it out and make an offer. Well we are $75 in on parts. I sorta tossed $400 at him and he said try it out see if we like it.
 
clean your radiator then clean your radiator then clean your radiator .see about 10 a year and they all say it is clean but over heats just had a Ford 2000 today looked clean but it was full of you name it two cans of brake cleaner then two cans of degrease and the pressure washer with hot water
 
Something bad wrong, that tractor should burn the belts off that mower before it heats. Check the blades make sure they are sharp, grease the spindles and look things over good. You can raise the mower by removing the wheel yokes and moving some spacers down but looks like it should cut where it is set.
 
No thermostat means the coolant flows to fast to be able to absorb the heat and then in turn has a hard time cooling the engine like it should. In your area I would probably go wit ha 160 degree thermostat since your summers are nice an hot. Or maybe the highest a 180. Also would not hurt to wash out the radiator so as to make sure it does not have a bunch of dirt stilling to the fins
 
your rad cores are plugged inside the rad. the outside can be clean but if coolant cant circulate through the cores it has no other option but to run hot.time for r&r and send to rad shop for a boil out.vinegar and other stuff is a waste of time and money when the core are plugged. dont you think thats why the thermostat has been removed? thats what people do once heating engine happens. thats lots of tractor for that mower.
 
Your 640 definitely has enough power to run a 6 foot finish mower. I believe your 640 is 30hp at the PTO so that is 5hp per foot.Remember they are just a big mower deck and really are made to mow a few inches of material to get nice results. Yes you can cut more. I have a 7 foot on my Ford 3000 and use it to only cut my lawn. Mine is a rear discharge. The side discharge will use more hp but the 640 is plenty of tractor for a 6 footer. Like others have said something else is wrong. I have two sets or blades and sharpen and change often.
 
You said the vent on the cap was up. That would make a big difference on it pushing water out the over flow.
 
What gear do you mow in? In first, you ought to be able to mow some very heavy stuff. If it's overheating and/or blowing coolant in first or second gear, something isn't right.
 
I'd have to agree with the other reply's. Used to run a 6 footer with an 8N and never got hot, side discharge too. You have cooling troubles. My 2 cents worth Greg NE
 
I agree with old: you need a thermostat for the cooling system to function.That tractor should barely know that mower is back there.Mark.
 
not so, without a thermostat the engine will run cool not hot, when the rad is not plugged.and when worked the coolant takes longer to get hot, and at idle will cool off lots faster. that is not a thermostat problem.
 
A tractor can run too hot without the thermostat. It's designed to get to a temp, and then dump the heat out of the hot water in the radiator. With no thermostat that process gets messed up, and the heat doesn't transfer properly.

Can easily be a plugged radiator, inside or outside, or a bad v belt or a worn out pulley that the belt is running on the bottom of the pulley, slipping.

That is a load for your tractor, but it should be able to handle it.

Paul
 
agree with the others that your 640 should destroy the mower before that engine would give up.

Flush the entire cooling system, the block gets rust and scale deposits that can give you overheating problems.
Without a thermostat, looking in the radiator neck should show very violent water movement if your pump is good.

make sure your engine is running good, paying attention to timing.
Make sure your advance mechanism is working. (most old tractors I buy, the advance weights are rusted stuck) Without the advance the timing will be far retarded at speed = no guts, and Lots of engine heat.

On your finish mower, adjust the wheel spacer blocks (looks like you're missing some) for a little higher cut. On my side yard with very heavy clover I run that mower a little higher. Freshly mowed....no one notices the difference between 3" high or 5" high grass.....
 
Before you do anything drastic might not be anything wrong with the tractor.It was a hot day,you were running it pretty hard at a higher RPM than usual and with the radiator full to the top with coolant.Water expands as it get hot so some will come out the over flow.I have several tractors that will do that once they push a some water out they are fine,just can't fill the radiator dead to the top.If no steam was coming out it wasn't really over heating most likely.
 
No, your 640 is a sister to my Jubilee. Depending on how tall the grass is, how sharp your blades are you may sometimes mow in second gear. 4.25 mph. I like a use first gear, 3 mph 1800 rpms. 1500 rpms = 550 pto, so my blades are spinning a little faster. Woods finish mower can handle it.

I like to mow wet grass, keeps the dust down. Yesterday I mowed lawn, 9 AM, lawn was soaking wet. I raised the front wheels off the ground about 2 inches. That chops the grass into very small pieces. When I was finished the yard had no signs of grass clippings.

A guy stopped by and asked how I keep my yard always looking immaculate. There is a lot of yards in my neighborhood with windrows of dead grass. They mow with ztr's in a back and forth pattern. I mow in a continuous pattern blowing grass towards the middle of yard.
a277816.jpg
 
I would think that should be an easy pull for a 640, I pull a 6' landpride with an Allis Chalmers CA on hills and unless I let the grass grow too tall I can handle it.
 
After the water level got down to the top of fins it was blowing a bit of steam out of over flow tube. Never had any issues with this tractor running hot. And as has been well documented on here we use the heck out of it. Radiator that came with tractor was leaking bad when we bought it. We bought a used one from a reliable source,so maybe we can add a thermostat and it won't be an issue. I know most folks take em out when things run hot. Or maybe we shouldn't try to kill the poor ol' thing?!? Lol
 

Robertshaw used to sell thermostats with a larger opening in the middle than other brands. If you can find one for your application it would be worth the couple extra dollars over a stant.
 
It has a shroud. I agree it makes a big difference. We had another 640 with no shroud and it ran a good bit warmer.
 
I'd be looking at the tractor. My very tired 8n handles this 6' Landpride with no problem. Just have to use 1st gear on the steep hills, otherwise 2nd.
a277820.jpg
 
IF you had the lever up on the cap, it did not provide any pressure. So yes,, under heavy load, hot day, you lost quite a bit of water. Flip the lever down... the water should be just above the core, usually a quarter inch when cold. As other said, make sure the fins are clean and you can see through them.


BE very careful cleaning the fins out as high pressure can and will damage them or bend them shut.

Other problems such as running lean, or timing being off will contribute to running hot as well. Make sure ground speed it not too high and engine is running at correct pto speed.
 
x2, don't overfill radiator, put in just enough coolant to cover the cores when cold.

I had my overflow dripping. Come to find out, I needed a new radiator cap. I also replaced my coolant. It was clean.

Watch temp gauge. Mine doesn't even get to middle.
 
Depends on what you were cutting. Thick bahai gone to seed with other stuff mixed in at 2 - 3 ft tall. Probably just overheated it. Yard grass 6 - 8 inches tall look for a problem somewhere.
 
It should handle that just fine so more then likely either to full bad cap or bad thermostat or lack of one or cooling system need a good flushing. When I say flushing I mean both inside and out side
 
I respectfully disagree-if the engine is being worked ,it will overheat.If under a light load it will run cool-if the weather is not real hot Mark
 
Shut that little safety thing. With it open the system was vented to atmosphere and couldnt build pressure. Just a little pressure raises the boiling point of coolant.
 
If that's the case, the 3406E I ran that had weak thermostats should not have needed half the grill covered to put heat in the cab when I was pulling a load through west Virginia.

Never got hot enough to kick the fan in.

The stat slows the coolant down so it doesn't flow through the radiator and dump heat too quickly.
 
(quoted from post at 17:23:43 08/23/18) clean your radiator then clean your radiator then clean your radiator .see about 10 a year and they all say it is clean but over heats just had a Ford 2000 today looked clean but it was full of you name it two cans of brake cleaner then two cans of degrease and the pressure washer with hot water
Click to expand...

Marlowe your post made me chuckle. I agree with you 100 percent. Park the tractor on cement, blow it out then hit it with the garden hose nozzle and let it soak. Hit it again with the garden hose, then blow it out with compressed air. If the water you blow out is dirty, and it will be, hit it with water again followed with the air nozzle. Do this until the water you blow back out is clear. It might take an hour or two, maybe longer. The reason why you park it on cement is so you you can visibly see how much junk came out of the radiator. It will be on the cement under the tractor. I have had to squeegee he mud off of my shop floor after cleaning a tractor radiator using water and air. Something else might be making the tractor overheat but at least you will know the radiator is clean.
 
You must log in or register to reply here.

Similar threads

D
Free Cub Cadet 122 . Worth Saving ?
Replies
12
Views
1K
DigJoe
D
3
Flat tire on my Dodge 3500
Replies
12
Views
1K
MARK ROBKE
M
jon f mn
A set back for the kingdom
Replies
13
Views
1K
dwag
D
R
Ford 640 ignition
Replies
7
Views
490
Steve@Advance
S
K
Question for Cub guys
Replies
7
Views
724
Blackhole49
Blackhole49
Tractor Parts Tractor Manuals

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.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top