Kubota D1105-T-E2B, not exactly speed talk:)

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Post Reply
User avatar
rcull
New Member
New Member
Posts: 49
Joined: Mon May 13, 2013 10:49 pm

Kubota D1105-T-E2B, not exactly speed talk:)

Post by rcull » Tue Dec 19, 2017 11:56 am

We are working with a Kubota D1105-T-E2B 3 cylinder Diesel engine. The specification for the bore size of the oversize piston we are fitting is 3.09055" to 3.09129". We finished the bore at about 3.0915" (Service limit is 3.09720"). We figured we had a piston clearance between .0035"-.0004"

The motor ran until it began to work. Temp climbed and it was shut down and disassembled. We found the center piston had picked up. The pistons were sourced from Kumar Bros.. The only info we had to work with was bore size, no piston clearances. I was concerned when the rings needed to be filed about .006" to get specified clearance.

The two end pistons still look good. The owner wants to buy one OE Kubota piston and ring assembly for the center and retry thinking because we are working to Kubota specs it should work fine. I feel we should at least open up the center bore .0005" regardless of what piston we put in. I would not even complain about opening the end cylinders .0005" and the center cylinder .001".

What we did not know when we started this is most of these engines have steam holes. This one is an early one and does not! There do not seem to be any specification differences for with or without steam holes.

Any comments?
Thanks

rfoll
Guru
Guru
Posts: 2220
Joined: Mon Jan 11, 2010 12:44 pm
Location: St. Helens, OR

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by rfoll » Tue Dec 19, 2017 12:40 pm

I had heard some of the 3 cylinder engines had problems, maybe this is why.
So much to do, so little time...

rustbucket79
Guru
Guru
Posts: 1543
Joined: Fri Apr 07, 2006 8:23 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by rustbucket79 » Tue Dec 19, 2017 12:43 pm

Did you happen to measure the clearance of the original pistons?
Supplier was no help? Most of the time the required clearance is listed in the catalogue.
Where was your measuring clearance, skirt tips/pin center line/top of skirt?

jred
Pro
Pro
Posts: 323
Joined: Sun Jun 11, 2006 12:14 am
Location: tucson arizona
Contact:

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by jred » Tue Dec 19, 2017 11:43 pm

I done a couple of kubotas.. most all the clearance's are std meaning everything is in metric so a bore of 73mm would have a piston of 72.94mm or close to that,, most all the diesels that I have done had about .004/.005 clearance on the piston to bore...

try this tradebit.com then type d1105 and you can download a service manual for a slight charge I use this all the time to get manual's that I don't have

User avatar
modok
Guru
Guru
Posts: 1720
Joined: Sun Jun 06, 2010 1:50 am

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by modok » Tue Dec 19, 2017 11:49 pm

I don't recall the specific details of one model or another, but I do recall a lot of those have very thinwall dry sleeves.
Factory would only have say, 0.25mm over pistons, if worn beyond that have to put in a new sleeve, which is struck me as rather stupid design, I mean, if the cylinders are too thin why put sleeves in them?? Whos design idea was that LOL, AND, get this, the new sleeve is .030 under std size, for some reason, so you have to bore it, or hone yourself to death.
All the new parts I've yest seen for those, bearings, pistons, rings... were really terrible quality.

That's all I remember. to know more I'd have to look it up same as you.

OH, and the blocks make great sub-blocks. I have a V1702 I use for all kinds of purposes. it's great for that. Already square on all sides and tapped full of holes. I hope they all die so I can collect pairs of them in each size, they come in 2,3,4 cylinders eh?/ eh?? just like a 123 blocks :D
Glen Urban

kimosabi
Pro
Pro
Posts: 260
Joined: Sat Feb 22, 2014 5:01 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by kimosabi » Wed Dec 20, 2017 6:52 am

Open up the bore .001. How did they manage to kill it btw? I have Kubota engine gensets, small wheel loaders etc and every time I change oil it's unbelievable how clean the oil is. The genset gets an oil change every 500 hours, oil is still not completely black.

Had another Kubota block genset in for repairs, the guy had been running it and restarting it after hot shut down probably 50 times. Upper coolant hose was gone. Looked in the cylinders and they were fine. New hose, new coolant and good as new. I'm a fan of Kubota. :D

User avatar
rcull
New Member
New Member
Posts: 49
Joined: Mon May 13, 2013 10:49 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by rcull » Thu Dec 21, 2017 5:48 pm

rustbucket79 wrote:
Tue Dec 19, 2017 12:43 pm
Did you happen to measure the clearance of the original pistons?
Supplier was no help? Most of the time the required clearance is listed in the catalogue.
Where was your measuring clearance, skirt tips/pin center line/top of skirt?
Haven't heard from the dealer yet. Measured close to the skirt bottom 1/4-1/2". Confirmed with a .003" and a .004" feeler gauge

User avatar
rcull
New Member
New Member
Posts: 49
Joined: Mon May 13, 2013 10:49 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by rcull » Thu Dec 21, 2017 5:54 pm

kimosabi wrote:
Wed Dec 20, 2017 6:52 am
Open up the bore .001. How did they manage to kill it btw? I have Kubota engine gensets, small wheel loaders etc and every time I change oil it's unbelievable how clean the oil is. The genset gets an oil change every 500 hours, oil is still not completely black.

Had another Kubota block genset in for repairs, the guy had been running it and restarting it after hot shut down probably 50 times. Upper coolant hose was gone. Looked in the cylinders and they were fine. New hose, new coolant and good as new. I'm a fan of Kubota. :D
I am sure in favor of opening up the center one .001"! The engine is in a lawnmower. It was installed in another shop, and run for 15 or 20 minutes. Then run around for maybe a 1/4 mile. The failure then happened shortly after the lawnmower was engaged and cutting.

Specifications were taken from the shop manual.

Jeff
Member
Member
Posts: 91
Joined: Sat Dec 17, 2005 10:53 am
Location: Michigan

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by Jeff » Thu Dec 21, 2017 9:03 pm

For the D1105 the bore is listed at 3.0709 to 3.0716 and piston is listed at 3.0680, this info is from a bulletin on prosis.
Jeff

joe 90
Guru
Guru
Posts: 2642
Joined: Tue May 27, 2014 4:02 am
Location: The land of the long white cloud

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by joe 90 » Thu Dec 21, 2017 10:13 pm

78 mm?
You'd make life so much easier for yourself using metric tools for measuring metric engines.

ProPower engines
Guru
Guru
Posts: 7245
Joined: Sun Jan 21, 2007 1:16 pm
Location: VICTORIA BC CANADA

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by ProPower engines » Fri Dec 22, 2017 12:18 am

rcull wrote:
Tue Dec 19, 2017 11:56 am
We are working with a Kubota D1105-T-E2B 3 cylinder Diesel engine. The specification for the bore size of the oversize piston we are fitting is 3.09055" to 3.09129". We finished the bore at about 3.0915" (Service limit is 3.09720"). We figured we had a piston clearance between .0035"-.0004"

The motor ran until it began to work. Temp climbed and it was shut down and disassembled. We found the center piston had picked up. The pistons were sourced from Kumar Bros.. The only info we had to work with was bore size, no piston clearances. I was concerned when the rings needed to be filed about .006" to get specified clearance.

The two end pistons still look good. The owner wants to buy one OE Kubota piston and ring assembly for the center and retry thinking because we are working to Kubota specs it should work fine. I feel we should at least open up the center bore .0005" regardless of what piston we put in. I would not even complain about opening the end cylinders .0005" and the center cylinder .001".

What we did not know when we started this is most of these engines have steam holes. This one is an early one and does not! There do not seem to be any specification differences for with or without steam holes.

Any comments?
Thanks
Having seen many small kubota's in the shop they do present many challenges when repairing the engines. And most have specific spec's based on the machine they are used in similar to the Yanmar diesel engines used in small farm machines pumps etc.
The bore and pistons have specific details that must be followed to the letter or failure will or can result.
Any of the kubota's need to be measured in at least 6 different spots at or in 3 different levels in the bore. The piston size is always measured at a specific distance from the bottom of the skirt for other engines and while this spec is often supplied the clearance is determined by finding the largest skirt diameter measurement.

As mentioned did this engine show any signs of using a flanged type sleeve?? They do required a specific piston based on the serial number of the block. ( learned that the hard way ooops). They are done this way to extend the useful life span of the block so if it does have a serious failure where the sleeve and block are too badly damaged you can repair the block by boring and finishing the bore and running the piston etc on the parent block surface in the bore but there is several over size flanged sleeves that can be but they have way different installation steps just like the originally installed thin wall sleeve. Meaning the block is not bored straight to instakk Kubota STD replacement or OS repair sleeves and I have seen some with what would appear to be really bad bores bores on a new replacement block. And when a call to Kubota was placed by me to talk to there tech/service guys they faxed me a tech drawing of how to measure the bores and where. I also talked with Dave Haggen at AERA for some other spec's they had on file and he sent ma just what kubota said.

That said it seems you have a slightly oversized piston set based on the bore sizes that are std factory sizes as mentioned above. the fact you had to file more then anticipated from the rings to get to spec may be a case of just making the rings to a larger size to fit other applications as well.

There is a place in Surrey BC called APD Distributors. 604-888-3726.
Thats is where I get Kubota parts from. They have genuine Kubota as well as they also have aftermarket stuff as well.

Just curious were the skirt oilers/piston cooling jets re-installed when it went back together?? it would be an easy miss if you did not take it apart the 1st time or bent and straightened out after.

Seen that before as well from local guys that didn't know any better lol

If you need some help with sourcing stuff give me a call I am not that far and we have talked before

Dave
Real Race Cars Don't Have Doors

naukkis79
Member
Member
Posts: 140
Joined: Tue Jul 29, 2014 5:14 am

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by naukkis79 » Sat Dec 23, 2017 5:10 am

Center cylinder should not need any more piston clearance than other cylinders. Are injectors checked, if injector is leaking or opens at too low pressure that piston will run too hot.

User avatar
rcull
New Member
New Member
Posts: 49
Joined: Mon May 13, 2013 10:49 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by rcull » Sun Jan 14, 2018 6:22 pm

The FOLLOW UP:

As suggested the injectors were sent away and found to be faulty.
The owner purchased a new set of Kubota pistons. Surprisingly they were a full .001" larger than the Kumar Bros. Going to the service manual, this could give them less than .0015" of wall clearance! The only specification is bore size, no piston wall clearances.

As the fit on the Kumar Bros. pistons was almost certainly satisfactory, it was decided to fit the Kubota pistons the same. We took the cylinders out another full thou. to between .0035 and .004".

The moral, our problem was probably injectors, and it was probably the injectors, not lack of maintenance that led to the low hour failure of the motor in the first place. Live and learn:)

User avatar
modok
Guru
Guru
Posts: 1720
Joined: Sun Jun 06, 2010 1:50 am

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by modok » Sun Jan 14, 2018 7:40 pm

Very good. That's pretty much normal IMO. The grand majority of piston and cylinder problems are caused by bad injectors.
I agree that type of piston the clearance must be at least .0025" min, so what is ideal I don't know but clearly they were too tight at nominal bore.
Glen Urban

tresi
Pro
Pro
Posts: 274
Joined: Sun Mar 24, 2013 10:10 pm

Re: Kubota D1105-T-E2B, not exactly speed talk:)

Post by tresi » Sun Jan 14, 2018 8:34 pm

Don't ever finish a bore to the size stated in the manual. Measure the actual piston for that bore and finish the bore to provide the required clearance.

Post Reply