B1750 Not Running / Rebuilding Questions

[Dwarner]

Found a 1995 B1750 HST Bi-Speed turn with a Woods loader on craigslist the price was good even though the ad said "engine overheated replaced battery, water pump and head gasket"
Looked into getting it running today but it was not firing at all and there was a smell of starting fluid. Valve clearance was about .030 so brought them to spec. Figured it was time for a compression test so off the Harbor Freight for a tester. All the cylinders had about 175 lbs. Pulled the head to look at the cylinders and there was heavy scoring on the wrist pin side of each cylinder.
Guess tomorrow I will look into a rebuild kit. Wondering if anyone has had luck with the ebay kits including sleeves?

 

[coachgeo]

Re: B1750 Not Running Craigslist

oww..... 175...... tis a bit low. Tractor data says:

Compression (PSI) Standard: 450 / Compression Lower Limit: 325

 

[lugbolt]

Ether: The nemesis of diesel engines.

That said, you're going to want to do a THOROUGH inspection of the engine before buying any rebuild parts. Why? Because you know the history. It's been hot. It's had ether used to start it. You could run into cylinder issues, broken pistons, bent rods, twisted/cracked crankshaft, a ton of things. If, for say you chose to pick up a rebuild kit, which is what? $1000? Then...pull the engine off of the tractor and pull it apart, then you find that the crank is cracked, you just spent $1000 on a rebuild kit and you'll have to find another crankshaft that isn't damaged, so $1400-$1500 or whatever a used crank goes for these days, this, that, and a ton of other stuff, pretty soon you're at new kubota engine territory. Thus, again, I would suggest looking that engine over really well before putting anything into it. I am dealing with an RTV900 as we speak, similar issue, guy bought a rebuild kit and wants me to do it....but didn't realize that the engine has more problems than a basic "kit" will fix.

 

[Dwarner]

After seeing the condition of the sleeves I definitely planned on engine removal for a complete inspection. I was surprised to see the scoring on one wrist pin side of each cylinder.
If the cost of repairs gets excessive I will be selling the tractor or parting it out. This is not my first rebuild and there is no hurry to buy parts until the cost is figured.

 

[kubotasam]

I saw that tractor on CL. Thought about looking at it. You beat me to it. Good luck on the repair.

 

[eserv]

After seeing the condition of the sleeves I definitely planned on engine removal for a complete inspection. I was surprised to see the scoring on one wrist pin side of each cylinder.
If the cost of repairs gets excessive I will be selling the tractor or parting it out. This is not my first rebuild and there is no hurry to buy parts until the cost is figured.

.5mm over pistons are available for that engine. It is unlikely but not impossible that other lower end damage has occurred. It is highly likely that the head is cracked.

 

[Dwarner]

I looked the head over it is flat as glass but I did not look for a crack. Do you know if cracks in the head would require magna flux?

 

[JeffL]

Magna flux is one good method for crack detection, unfortunately, hard to fine a skilled technician any more. I would recommend buying a dye penetrant kit and checking the head and other components yourself. Just follow the instructions on the cans exactly and ignore all the other advise on how to do the check. Jeff

 

[North Idaho Wolfman]

I looked the head over it is flat as glass but I did not look for a crack. Do you know if cracks in the head would require magna flux?

Normally no need to Magna flux them, look at the area around the valves, and from the valve to the pre-chamber, that's where they crack, the cracks are usually very prominent.

 

[Dwarner]

Stopped by my local machine shop today to get an idea of prices for re-sleeving my B1750 engine. He also gave me prices to polish the crank and service the head. His work without parts came to about $850 that got my attention. When I add in my cost for the factory engine parts the number is edging closer to $2000. My cheap Kubota B1750 isn't going to be so cheap. Trying to decide whether to fix it or send it down the road.

 

[Dwarner]

Finally finished disassembling the D950 engine. Even with the wear marks in the cylinders the bores still were within spec. so I ran a cylinder hone to see how it would clean up and it looked pretty good. I took the block to Eastwoods machine shop in Somers CT for his opinion. His concern was that several locations in the bore were under spec probably from the engine running hot. Since 2 out of 3 of the pistons were damaged he will be reboring the engine .5mm over no new sleeves needed. All the crank rod and main bearings are in excellent condition happy lubrication was not a problem.

 

[SCCTP]

Stopped by my local machine shop today to get an idea of prices for re-sleeving my B1750 engine. He also gave me prices to polish the crank and service the head. His work without parts came to about $850 that got my attention. When I add in my cost for the factory engine parts the number is edging closer to $2000. My cheap Kubota B1750 isn't going to be so cheap. Trying to decide whether to fix it or send it down the road.

I am in the same boat, found a B1750 running but smoked, thought it might just be a head gasket, took head off and found out head had a crack.
Like you I am now deciding if I need to repair or send down the road.

 

[Dwarner]

Just got the block back from the machine shop and will be putting it back together this weekend. The cylinders were bored .5mm over. Plasti gauged the bearings and all were excellent but I decided to polish the crank and put in new bearings. Tractor had a new clutch however I found the clutch disk cracked. The crankshaft pilot bearing was toast but a new one is extremely loose in the crankshaft. The plan is to have a new pilot machined to fit the crank or go to a ball bearing in place of the seal. A 14 mm id bushing will still need to be installed in the bearing since 14mm seems unavailable. Rebuild parts and machine shop work cost so far $1350.

 

[Jpatrick]

Another option to consider here is getting a used engine or rebuilt engine from a salvage yard like ASAP (All States Ag Parts) or elsewhere. You'd probably be in to something 2000-ish with returnable core charge in the neighborhood of 500-700 but you do pay shipping both ways.

There might also be other engines that fit that bell housing.

 

[Dwarner]

I did find a used D950 engine with only 325 hours on Ebay. It sold for $800 but it was in SC possibly a marine engine but I'm not sure. Shipping was an issue. Hope to have my engine running soon.

 

[Dwarner]

The rebuild using only Kubota parts went well. A few concerns but now a great running engine. The rest of the tractor has it's share of problems but not costly just time consuming. Thank you for all your input.