B7100 Engine Swap

CowboyChris

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Jan 1, 2020
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Hey! I am currently in the process of swapping my D750-a D850. Before I get into detail, I want to give you a back story. So I bought this B7100 4x4 from a good buddy of mine. When I pulled it in my building to work on it, I soon realized the engine was locked up. My first thought was to simply pour a special homemade mix down the cylinder head (half transmission oil and half paint thinner). When I pulled the head off, I was shocked! It was full of water and rust. I decided I must rebuild the engine and was debating whether I should put new sleeves, or simply hone it out and just put new rings in. After waiting for two weeks (often rocking the engine over with a 3/4 socket). However, the tractor would not break loose. I decided to pull the engine and rebuild it completely. With the engine now sitting in the shop, I had a crazy idea of swapping the D750 with a D850 I had stored away. So I did. . . Everything went smooth. there were only few parts I had to swap over from my D750. 1: the in-tank man.; 2: the flywheel and clutch; 3: the engine mount plate-transmission.After all this, I realized that the radiator was different and the water pump was not interchangeable. Is there any way I can mount the radiator on?

Sorry for the long story!
 
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North Idaho Wolfman

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The radiator for the D750 (thermo sipon)will work with the D850(water pump), you just need to solder in copper pipe reduced in the inlet and outlet, the bottom one needs to be put in at an angle if I remember right, did mine years ago.
 

CowboyChris

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Jan 1, 2020
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Thank you for your reply. What about an 1105 a? I might throw an 1105 a in my other B7100. Would that radiator fit as well you think?

Blessings
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
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Thank you for your reply. What about an 1105 a? I might throw an 1105 a in my other B7100. Would that radiator fit as well you think?

Blessings
I do believe there are way too many differences in a D750 to a D1105 to even get it to fit easily or properly.

Someone else was trying to do it and never reported back on how it went so my assumption would be they were not having much success in doing it.

But if you could get it to clear everything the radiator should work fine.
 

Sparkye

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B7100
Aug 6, 2018
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Chicago
Hey! I am currently in the process of swapping my D750-a D850. Before I get into detail, I want to give you a back story. So I bought this B7100 4x4 from a good buddy of mine. When I pulled it in my building to work on it, I soon realized the engine was locked up. My first thought was to simply pour a special homemade mix down the cylinder head (half transmission oil and half paint thinner). When I pulled the head off, I was shocked! It was full of water and rust. I decided I must rebuild the engine and was debating whether I should put new sleeves, or simply hone it out and just put new rings in. After waiting for two weeks (often rocking the engine over with a 3/4 socket). However, the tractor would not break loose. I decided to pull the engine and rebuild it completely. With the engine now sitting in the shop, I had a crazy idea of swapping the D750 with a D850 I had stored away. So I did. . . Everything went smooth. there were only few parts I had to swap over from my D750. 1: the in-tank man.; 2: the flywheel and clutch; 3: the engine mount plate-transmission.After all this, I realized that the radiator was different and the water pump was not interchangeable. Is there any way I can mount the radiator on?

Sorry for the long story!
I've done the swap, three years ago . The radiator has to go forward one inch. This along with the hood. I used the original radiator without modification. Bushed the hoses which has worked fine. Bought the metal lower radiator hose adapter from a B8200. Lower hose is very short after install. I just extended the hood with metal extensions I made. It sits forward now, but shuts fine. Also had to move the hydraulic plate cooler forward too. Had to use the oil pan and pick up from the D750 too. I put an alternator with an internal regulator too. Had to modify the drivers side panel for that. Installed temp, oil pressure and voltmeter gages too. After complete its a different tractor, I use it for snow plowing and The old D750 was shot and it was weak. With The D950 nothing stands in its way. I can also run a 5 foot bushog with it now. If you need pics, let me know
 
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North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
can someone tell me if you can engine swap b5100e 2 cylinder to 3 cylinder
Not unless you find a fun way to stretch the frame!
Or use the frame out of a B6100E or B7100E.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
Yes and no, The frame bolts to the sides of the block not to the front.
I've worked on quite a few of these!

Top pic is a B5100 (2 CYL frame)
Bottom pic is a B7100 (3 cylinder frame)

If you will note the Frame bolt hole differences between the two.
One will not interchange with the other.
This doesn't even bring into play the side covers and hood are also shorter, along with a host of other parts.
Buy a B6100, or B7100 if you want a three cylinder tractor.

B5100
1678296746725.png


B7100
1678296694629.png