D850 head gasket question

oldbiker

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D722 grasshopper, D850 wood splitter
May 11, 2021
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indiana
New to this forum - my first post
I'm a lifelong mechanic and totally diesel ignorant. So far it looks like kubotas are going to be pretty easy (probably famous last words). I'm currently waiting for parts to replace the head gasket on my D850. I've been installing head gaskets in trucks, motorcycles and lawn mowers with hard grease for 50 years and not one has ever blown. My question is will it work on a diesel and if not why? I also hate things that defy logic. Does anyone know how is kubota getting away with such low head bolt torque?
 

Motion

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I know on a D902 Kubota doesn't recommend a head gasket sealant, however I use Permatex #3 on head gaskets (gas or diesel) and 3in1 oil on the head bolts. Just my .02
 

whitetiger

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Do not put anything on the head gasket, it has its own sealer in it. Never add anything to a head gasket unless the installation instructions specify to do so.
Use only engine oil to lubricate the head bolts and studs.
Remember to replace the valve train oil supply dowel o ring, it does not normally come with the head gasket.
 

oldbiker

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D722 grasshopper, D850 wood splitter
May 11, 2021
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indiana
Never heard of this. Please explain.
Lil foot

I learned most of my best tricks listening to old men. The old men sealed all there gaskets with wheel bearing grease. I believe in technology prematex had it's day and rtv is now king, but I have never had a greased head gasket blow. I'm still driving 2 ford trucks with engines I rebuilt over 10 years ago.
 

Lil Foot

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Thanks, learned something new today.
 

D2Cat

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Whitetiger said, "Remember to replace the valve train oil supply dowel o ring, it does not normally come with the head gasket."

Pay heed to that comment. That o ring is at the rear left side of the block. You leave it out (because you're not familiar with it and what it does) will cause you to remove the head again to get to it.
 

GeoHorn

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One reason oil filters can be hard to remove is becauae oil or grease was used to lube the gasket, which then hardens and sticks the filter to the block. But I never heard of using grease on a gasket til now.
 

oldbiker

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D722 grasshopper, D850 wood splitter
May 11, 2021
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indiana
Whitetiger said, "Remember to replace the valve train oil supply dowel o ring, it does not normally come with the head gasket."

Pay heed to that comment. That o ring is at the rear left side of the block. You leave it out (because you're not familiar with it and what it does) will cause you to remove the head again to get to it.
D2cat and Whitetiger

I did notice that o-ring and will replace it. It would be easy to miss thanks for the heads up.