Head gasket on a 850

[DieselSJ]

Hi all! Just picked up an 850. It fires right up but it is blowing coolant out the radiator. I'm figuring head gasket. Tractor has 3500 hours on it. How robust are the heads on these? In other words, how likely would it be that the head is warped/cracked also?

Thanks!

 

[beenthere]

:welcome:
Do you know the history of the engine? I suspect not, being it is just picked up.

Might plan on the worst, but hope for the best when you pull the head off.

 

[DieselSJ]

Don't know the history. The person I bought it from had bought it at an auction just a few weeks ago. When he found the problem he just wanted to get rid of it. There is a tag for one of the community colleges on it so I'm thinking it was used for groundskeeping at the college. Oil does not appear to have any water in it, so that is keeping me hopeful. Only paid $1500 for it.

 

[DieselSJ]

Good news is that it just looks like a head gasket and not a cracked head or block. Dropping head at machine shop today to get checked for cracks and have it surfaced.

 

[Wolfy]

I have a Ford 1600 which is a little bigger than a JD850. 3,500 must be the magic hour mark since that is when my headgasket went. I had antifreeze boiling out and getting into the oil, but both problems stopped once the headgasket was changed. My dad had a JD750 a long time ago, it was a very good tractor, those Yanmars don't quit.

 

[RickB]

Hi all! Just picked up an 850. It fires right up but it is blowing coolant out the radiator. I'm figuring head gasket. Tractor has 3500 hours on it. How robust are the heads on these? In other words, how likely would it be that the head is warped/cracked also?

Thanks!

Those cylinder heads are quite fragile. If it was overheated, chances are good the head is cracked. Hope yours isn't.

 

[DieselSJ]

Ya, machine shop called me today and they found cracks. I'm dropping off the water pump and back plate in the morning so they can pressure test it and see if the cracks are into the water jackets. I'm on the lookout for a good used head just in case.

 

[wildcatfan]

sorry to dredge up older thread. What wsa the final outcome of th repairs to the head. Friend has one with mid mount mower he's looking to sell.
May or may not be agood deal depending on cost of repairs as I'm sure the hours are probably similar

 

[DieselSJ]

Head was cracked in multiple places, including up through the injector pockets. Machine shop I was using had to send it out to a diesel specific shop to get it repaired. Lots of welding and re-machining. Total repair cost on the head was just shy of $750. Just slightly cheaper than what I found rebuilt heads selling for.

But she has been up and running great ever since. I'm still way ahead on what I have into the purchase price and repairs vs what I would have paid for a good running tractor.