John deere 855 tractor yanmar 3tn75rj engine rebuild help

[jaydee325]

Deere parts shows pistons and rings are available in .010" and .020" over.

 

[TractorGuy]

I have a manual. PM me if you are interested in it

Nice little machine...enjoy it

The link in post #5 appears to be the correct CTM3 manual that was renamed. It has a download icon at top right when it loads.

Oddly it has language talking about damage to liner o-rings if you use the wrong coolant. That must have been a generic comment for engine that may have liners. In the parts available it makes no reference to liners other than boring.

Just says:
SERVICE PARTS KITS
The following kits are available through your parts catalog:
Cylinder Block Gasket Kit
Cylinder Head Gasket Kit
Oversized Pistons and Rings
Undersized Connecting Rod Bearing Inserts

 

[dfkrug]

I have had 4 JD955s and rebuilt the engines on 3 of them. I used 0.5mm O/S pistons from the maker. The machinist I hired to do the boring also would have bored and installed liners if necessary. I don't know if the liners would have bet "wet" (into the water jacket). I have yet to do a liner rebuild, but it is a common solution, and may not require buying new pistons, just rings and the liners.

All 3 engines I rebuilt were "dusted", so my bearings were in-spec and not replaced.

 

[jd3020u]

Did you find any problems with the air cleaner housing? Wonder how many of these suffered short lives from this.

 

[woodtractor1]

Thank you for the replies! I looked inside of the air hose from the air box and it was coated with fine dust! There was one large air filter in the air box but I read that there is also supposed to be an inner air cleaner??? Am I understand this correctly? 2 air filters?

How can I fix the "dusting" problem? Have any of you found a solution? Thank you.

 

[TractorGuy]

Most tractors will have an inner and outer air filter. If I remember correctly my old 855 had a small diameter inner filter with what looked like a layer of gray felt and the outer filter was the pleated paper type.

 

[jd3020u]

Wish I would have taken a picture but I think a spot weld cracked for the center piece that the wing nut threads into? Could tighten the nut but it didn't really pull the filter tight. I did reuse the housing.

Been 10 years already since that project!


Be sure to clean the intake ports out good.

 

[dfkrug]

On my JD4300, the intake hose was worn thru near the top of the engine. Of the 955s I had, it has been so long, I do not recall how the air filtration failed. All my JDs were rental tractors that I rebuilt.

The 4300 rebuild I documented on TBN.

Two air filters are common on many CUTs. My own CK30 has a place for the inner filter, but the tractor did not come with one. The nearly identical Bobcat CT230 I bought had the same filter housing, but had both filters. I do not operate in dusty environs, so I am OK with just the outer filter.

 

[TractorGuy]

The dual filter setup MUST work. My backhoe had dust in the headliner an inch thick from working in dusty environments but it's engine survived. Every panel I removed on it was caked with thick dust. Both filters were slam full of dust but inside the inner filter looked okay.

 

[dfkrug]

The dual filter setup MUST work.

Yeah, that's what it is for, and they DO work if the filter housing and all the hoses stay intact and properly installed. Dusty environments need good filtration.

I just bought an aftermarket air filter for a Kubota, and I can see differences between it and the Donaldson it used to have. This Kubota has only the outer filter, and no provision for an inner filter.

Eventually, all that dust, plus moisture affect the electrical connections, and you get intermittancy. Newer tractors seem to have mostly gone to sealed electrical connectors, like you see in the auto world. A good thing.