1978 John Deere 850 Project

[wct097]

I don't know anything about the Yanmar engines except mine have worked well without problems. That said the older engines with wet liners would be beneficial in your case. I rebuilt my old 450 dozer with new pistons and liners rather easily in a day or two.

Any possibility you can salvage the bore by honing?

I don't believe the bore can be salvaged. Given that it is a wet liner, I feel fairly confident that I could replace it myself. Since the head is already disassembled and needs work, I'm planning on disassembling the lower end this weekend to take both a machinist. I'm hoping I can get by with a replacement sleeve, rings, bearings, and having the other two cylinders honed. Should know more next week. Provided the block and head are not cracked, this should be a relatively simple rebuild.

 

[jenkinsph]

If it has wet liners then it should be an easy fix.

I would have to step back and assess the tractor carefully to try to figure out what it would take to fix it overall. If reasonable I would do it if not I would part it out. I would imagine that's where you are, decisions, decisions. Good luck with it.

 

[wct097]

If it has wet liners then it should be an easy fix.

I would have to step back and assess the tractor carefully to try to figure out what it would take to fix it overall. If reasonable I would do it if not I would part it out. I would imagine that's where you are, decisions, decisions. Good luck with it.

I'm only into the tractor for $1000. I'll know more once the machinist has a chance to inspect the head and block. Assuming no cracks, I'm thinking I can do a rebuild for under $1500 which would put me at $2500 before I start replacing hydraulic hoses. For a 2wd ~25hp FEL tractor, I figure that if I'm up and running for under $3k, I'm doing pretty good. If the machinist comes back at $3k for the rebuild, then I'm leaning towards parting it out. I had a long conversation with one of the two machinists I talked to about this engine. The short story is that these independent guys make money on the work and still charge a fraction of what the dealer would charge for the work.... so much so that the dealer sends him work and charges the customer a markup on it.

 

[murphy1244]

I hope you can do the rebuild.:thumbsup: I love rebuild threads. With pictures is even better..

 

[murphy1244]

If it has wet liners then it should be an easy fix.

I would have to step back and assess the tractor carefully to try to figure out what it would take to fix it overall. If reasonable I would do it if not I would part it out. I would imagine that's where you are, decisions, decisions. Good luck with it.

Steve, How much did you sell your 830 for? That was a great machine. Wish I could find one out here but sure is rare.

 

[jenkinsph]

Steve, How much did you sell your 830 for? That was a great machine. Wish I could find one out here but sure is rare.

$6200 for it, pretty good tractor in good condition. It was going to need an injector pump rebuild but that is about it.

 

[murphy1244]

$6200 for it, pretty good tractor in good condition. It was going to need an injector pump rebuild but that is about it.

The only 830 I've found here was a spray paint restore for 8500$. Its still there. Yours was a really good price for a great machine.

 

[wct097]

I hope you can do the rebuild.:thumbsup: I love rebuild threads. With pictures is even better..

I'm inclined to rebuild it if it's doable. I've got it on an engine stand in the basement right now. Going to take it apart over the weekend so I can deliver the block to a machinist next week. Unfortunately I'm homeless right now while my house is being built, so I don't have a proper shop. If I get the engine rebuilt and the tractor running, it'll be a while before it gets cleaned up much beyond what has to be done to get it running. Longer term, I'd like to do some rust abatement and repainting, but for the short term it's probably just going to be engine and hydraulic hoses.

 

[murphy1244]

Got to start somewhere's so it might as well be with the heart of it all.

 

[pmsmechanic]

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