Kioti with Kubota engine clutch vibration

[kubotasam]

I checked the crankshaft for back and forth play and it has roughly 1/8 inch of slack.

Not sure what the specification is for crankshaft end play on your tractor but I know 1/8" is way to much. When you push the clutch pedal in it pushes the flywheel forward and holds the crankshaft steady.

 

[Ekm]

Is it possible you have a defective clutch disc? Like the splines are not centered in the disc.

You have the vibration when the disc is against the flywheel, but now when they are separated. Has to be something behind the flywheel.

I'm using the same disc that was in it before engine replacement, had no problems with it with old engine.

 

[Ekm]

Did the pressure plate have an alignment pin or pins?

No alignment pins, I marked it before removal and reinstalled the same way.

 

[Ekm]

Not sure what the specification is for crankshaft end play on your tractor but I know 1/8" is way to much. When you push the clutch pedal in it pushes the flywheel forward and holds the crankshaft steady.

This is what I'm leaning towards being the problem. Just not looking forward to an engine tear down to fix it, especially on an engine I bought for a replacement.

 

[lugbolt]

I normally don't get involved with these Kioti's (gray markets), but did you check for a pilot bearing/bushing? Is it the correct size for the transmission input shaft? Is the crankshaft's depth the same, in that is the transmission input shaft going all the way into the pilot bearing/bushing?

I think we're finding out that conventional wisdom would think that the engines should be identical, they're really not. Something is not right, or it wouldn't be a vibrating.

 

[DVoss]

I checked the crankshaft for back and forth play and it has roughly 1/8 inch of slack.

My guess is that the crankshaft endplay should be on the order of .005-.010....definitely not 1/8".

When you apply some pressure to the clutch, the pressure takes up the endplay.

 

[Ekm]

Well I think I found the problem. I split it back into this morning removed the clutch and pressure plate. I put a pry bar in between the flywheel and and housing and found the slack is actually vertical slack in the main bearings. It only seems to be in the rear not in the front. Guess I'm going to have to tear it down and put new main bearings in it. Cross my fingers and hope the crank isn't ruined.

 

[steveInMaryland]

I certainly don't know this engine but does this particular engine have a thrust bearing? Replacing the mains is a great idea but it sounds like a worn thrust bearing. Just my 2 cents.

While it is upside down please replace every mating surface you can.

Cheers

 

[Ekm]

Yes it does have thrust bearings. I can see the main bearings have spun and are being squeezed out of the journal. I haven't pulled the crank yet, but I'm sure it's pretty scarred up. Does anyone know what is the largest undersized main bearing made for the d1402?

 

[North Idaho Wolfman]

Yes it does have thrust bearings. I can see the main bearings have spun and are being squeezed out of the journal. I haven't pulled the crank yet, but I'm sure it's pretty scarred up. Does anyone know what is the largest undersized main bearing made for the d1402?

You can get .20mm or .40mm bearings.
DI or IDI engine, you need to know the difference before you order bearings?

 

[Ekm]

Finally had time to take take the crank out. I'm going to upload a couple of pictures. It's not bad as I thought it was going to be. What do y'all think?

 

[Tooljunkie]

Rub the edge of a penny across the grooves. If it leaves copper behind then it needs work.
Still needs to be cut from the look of the photos.

 

[North Idaho Wolfman]

Yea your looking at having it turned, here is hoping it's under .04mm.

 

[CountryBumkin]

It doesn't look too good in the photos.
You may be able to clean it up by running some 400 grit emery paper (the kind that comes in a roll) over the journals. If you can feel a ridge or groove with your finger nail then you need to take additional action. You would also want to have a micrometer at hand to measure the journals (diameter, and to check for out-of-round and taper).

 

[D2Cat]

If you're going to clean it up some, here's a method that works pretty good.

Get some long flat shoe laces like those in kids tennis shoes. You can get them at Wal-mart for $2 a pair. Buy the longest they have.

Get some FINE valve grinding compound. Apply some of the compound to the journal. Wrap the shoe lace around the journal 3 times. Now just pull back and forth like you're sawing wood.

It will do an amazing job, and give you even polishing and not promote out-of-roundness.

 

[Ekm]

Thanks for the input guys. I'm going to take it to the machine shop to be turned. I was expecting it to look a lot worse. Glad it isn't too far gone, Good thing I shut it down when I did.