850 still running hot

I went to farm yesterday put in 160 degree thermostat, moved timing back and forth nothing seems to make any difference. runs hot within 10 minutes. Radiator is clean, belt is tight, nothing seems to make any difference. Do they have to have a fan shroud to stay cool? Next question does YT not sell two stage clutches? I can not find a listing for them.
Ron

They do sell a fan shroud and it does make a differance

Ron;

Fan shrouds are designed to help direct the air and cool the engine. There have been a few posters who re-installed the shroud and it helped. Have you checked the radiator when the engine is up to temperature to see if you have circulation? If there is no circulation then the problem is a restriction of some sort or the impeller of the water pump has broken. (never seen this myself, but heard of it) When was the last time the block was flushed? A lot of gunk can build up in the block. When you run the tractor and it heats up, use a meat thermometer to check the temp in the radiator to confirm your gauge has not gone bad. The timing should be at 4 degrees before top dead center. Is your distributor spark advance working properly? Have you checked the hoses to see if they collapse during operation? Drain the oil from the engine and check for watewr in the oil. If there is water in the oil remove the spark plugs and check for water at the plug holes. With the engine cold, fill the radiator to the top. Remove the belt so the water pump will not work. Run the engine at fast idle for 60 seconds. If water runs out of the radiator filler pipe or overflow, or if bubbles come to the surface in the radiator, leakage exists between one or more of the cylinders and the cooling system. It could be a blown head gasket or a leak has developed between a cylinder sleeve and block.

If you have leakage, check the head bolts for proper torque. If none appear loose, remove the head and inspect for a bad head gasket. Look for cracks in the head in the area of the valve ports. If ok, replace the head gasket and re-torque the head to 65-70 ft lbs. Warm up the engine and then re-torque the head. If your engine was rebuilt and they did not re-torque the head, if may cause a leak.

While the head is off, inspect the water jackets of the block and head for lime deposits that restrict flow. Hope this helps. Post back with what you find.

Forgot to tell you, They do sell double clutches here. See link and scroll down the page. If you have a double clutch, you don't have a 850, but and 860 with live PTO.
Clutch

I had this problem with my 850 a few years ago. It would gradually heat up to where I'd have to shut it down and let it cool off. I took an air hose and blew out the fins on the radiator and made sure there was no debris. Still heated up. So when I was working it and it heated up I put it in high gear and took off down the road and the extra airflow would bring the temp. down. Put in a new radiator and problem was solved.

while the shroud does make some difference.. it shouldn't be a go/no go for an otherwise health machine.

ensure the t-stat opens when hot.. pot o' water will tell you that.

next do a couple flow tests.. take top hose off rad and aim into bucket ( after you remove tstat ).. start tractor.. should pump water out real good... if not.. pump has problems..

next.. run garden 1/2" hose into rad neck... remove bottom hose..... turn on water.. rad should be able to flow full 1/2" hose opened all the way up, and flow thru core and drain out bottom with no overflow from top.. if not.. rad is plugged..

soundguy

Ron, Remove your radiator and take it to the shop.It should be rodded out and cleaned.You should also install a fan shroud.Most have been removed because the the center pin bushing on the front axle was worn and caused the shroud to contact the fan blade.I have also seen the impleller rust off the waterpump.

I had this problem last year in my 860, and noticed I had small leak in the radiator. I took it to the shop for repair, and they told me it was basically half plugged up. It was cheaper to just buy a new radiator (~$190). New radiator installed and even in 110 degree heat last week I couldn't get the temp gauge up to the halfway point in the green. When it was 75 degrees I could barely get it into the green at all. Huge improvement. After 50 years, a ton of sediment and rust can build up in those radiators, even if they are clean (mine was).

Do the flow test Sounder recommended, and it should tell you if you have that problem.

Greg

Thanks guys. I will look at those possibilities. I looked in my spare parts and found a good shroud. I knew I had everything else. Thursday I am going to head to the farm armed with a shroud, another radiator, water pump,4 blade fan, and some freeze plugs. I may just bring it home so i can work on it here. It is an 850. The clutch is for my 961D I was wondering what the cost. Thanks again.
Ron