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My First Kohler - 6R0Y61

JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Today I picked up my very first Kohler and it is a diesel with 63 hours on the clock. I know nothing about Kohlers and nothing about diesels. Obviously I have a lot to learn.

First, I want to give a BIG thanks to RMAK (Ross) :wave:. He frequently browses postings on the STAK, but seldom posts and I never knew he existed until he contacted me by private message about 1.5 weeks ago. He knew I was looking for a diesel from another STAK forum that I frequent. Ross came across this Kohler from a friend that was taking it to the scrap yard because of a head gasket problem. Ross wanted to fix it, but had no spare time due to too many other projects. Ross was generous and offered it to me for free as long as I post details on restoring it here. I agreed and it now sits in my garage and the postings will begin now.

In about an hour or two after getting back to my garage, I tore the entire top end off of the motor and seen the problem that was the reason for the original owner wanting to junk the genset. Tonight I will be posting pictures in multiple postings showing the Kohler as it rolled into the garage, the tear down and the problem.

OK, let's get started with my Kohler project. I attached 4 pictures below to give you all and view of what I hauled home tonight with explanations of each picture as follows:

First picture: This is the data tag showing the model, serial, spec level and other data.

Second picture: I got a close up of the motor and obviously it is a diesel made by Yanmar. I have no clue on its displacement or anything since I can't any manuals for the motor or the genset online. By the way, I have all the sides for the enclosure.

Third picture: The dashboard clearly shows 63 hours on the clock. Basically, it is not broken in yet.

Forth picture: This is a shot of the other side of the motor. Looks new and in perfect condition, but don't be fooled!!!

More pictures will be posted shortly.

JohnnyC
New Jersey
 

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JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

... more pictures -

To continue, the owner prior to RMAK was told that oil was getting into the intake manifold and needed a head gasket and may have been the reason why this genset was considered scrap. I scratched my head trying to figure out how oil could be getting into the intake manifold and how that relates to a head gasket.

As soon as I got home I immediately got to work on the Kohler. After doing a detailed visual inspection, I did not see any signs of oil in the intake manifold, but noticed it had a brand-new water pump (see First picture below), new oil and fuel filters and the oil looked as if it was just poured into the Kohler's crankcase today. Something did not seem right. Why all this work, but the head gasket was neglected?

Next, I wired up a battery and attempted to start the Kohler. The motored was LOCKED. I did notice that the crank wiggled a little as I hit the start button so I assumed it may be hydrolocked with fluid. To verify my thoughts, I removed the injectors and attempted to spin the motor over using the starter. Sure enough, tons of fluid came out of all 3 cylinders and made a brown muddy mess all over the motor (see second picture below).

Worse yet, the fluid in the 3 cylinders shot out with great force and plastered the rafters in my garage (see third and forth pictures below). Luckily my friend moved out of the way before I spun the motor over or he would have been hurting). Now the motor spins freely, but obviously I needed to dig deeper to find and fix the root cause of this problem.

--- to be continued.

JohnnyC
New Jersey
 

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Troll

Registered
Last Subscription Date
08/10/2017
Re: My FIRST Kohler - 6R0Y61

Had a few of those with cracked heads through the cooling passages.
 

JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

... more pictures -

I continued to tear down the motor's top end to try to find the root cause of the problems and how much damage took place. I started by draining the coolant and was surprised to see it came out like a bad case of diarrhea (see first picture below). There is no oil mixed in. When oil and water mixes in a cooling system, you will see white crap and some separation. This was a consistent mix of something like diarrhea which is the best way to describe it.

When it came time to remove the "new" water pump, like looked as if someone took a crap in the water passage way behind the pump (see second picture).

The third picture shows a small something that I pulled out of the coolant passage way. It felt like one of those bad experiences when you have toilet paper failure while wiping yourself on the porcelain pony.

In the forth picture, I can not figure out what's going on here. I removed the valve cover and it looks brand new.... Too new.. I see NO signs of oil reaching the rockers. It is bone dry. I am clueless what is going on here. Anyone care to explain?

.... More pictures and the story will continue shortly. Stand by..


JohnnyC
New Jersey
 

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JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

This set of pictures show what is looked like after removing the head. I can sum it up in 2 word "freaken mess".

The first picture below shows the under side of the head. Clearly, there is a problem. I could not tell where the head gasket failed since it looked a mess too.

The second picture shows the block and pistons. Can you notice that the coolant passages around the circumference of each piston is almost 100% blocked with a semi hard sludge? The head passages in the prior picture too.

The third picture shows one he!! of a mess. I am loosening up the semi hard crud and blowing it out of the coolant passages. What you don't see is the mess all over my garage as a result of this crud blowing out under the force of compressed air. It looks soft here, but is was originally much thicker. I covered the push rod holes with a rag to prevent this crud from going down into the crankcase.

The forth picture shows the coolant passages semi opened as a rults of compressed air, but it will require flushing.

In conclusion, I think what happened is this genset's coolant was neglected over the years and crud formed (block and head is iron) causing a 90% coolant blockage. Since there was a blockage, the head overheated and resulted in a head gasket failure. I do not know if the block's deck and / or the head surface is warped. Also, I do not know if any other damage resulted.

My path forward is to continue cleaning and looking for additional damage.

JohnnyC
New Jersey
 

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Troll

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Last Subscription Date
08/10/2017
Re: My FIRST Kohler - 6R0Y61

Straightedge the block too. Had to renengine two sets when overheated. Don't remember the culprits as it's been a few years. Since that run we only get four cylinder 4.5 ltr JD diesels any more. Usually Yanmar are worth rebuilding but for some reason they didn't fare so well for us. Great engines in compact tractors though.....
 

JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

Straightedge the block too. Had to renengine two sets when overheated. Don't remember the culprits as it's been a few years. Since that run we only get four cylinder 4.5 ltr JD diesels any more. Usually Yanmar are worth rebuilding but for some reason they didn't fare so well for us. Great engines in compact tractors though.....
I never heard of a Yanmar until last week and I thought it was Chinese. When I found out it was Japanese and built with quality like a Kubota, I will give it my best shot to restore it. If the head is cracked or a major block problem, I may throw in the towel.

I am baffled about the lack of oil at the rocket arms. It looks totally 100% oil free as seen in my previous picture. Likewise under the valve cover too, but yet has 63 hours on the clock. When I was cranking the motor with out the injectors, the motor was building pressure and the Hz meter went as high at 35-40 Hz. Obviously the motor was not spinning at 1800 rpm to produce 60 Hz.

I need manuals for the motor and Kohler manuals are hard to find, unlike Onan. I will search using Yanmar on the web tomorrow.

I am currently uploading a video showing the coolant being blown out of the cylinders. The liquid came out under great force. Also, shortly afterwards while my friend and I were looking closely are the top end of the motor, the generator automatically tried to start. We jumped and ran for cover knowing that if anything else was in the cylinders, we would have had a face full.

JohnnyC
New Jersey
 

slip knot

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Last Subscription Date
12/27/2019
Re: My FIRST Kohler - 6R0Y61

ugh, those unsupported cylinders remind me of the early Vega I4 engines. I never could get a head gasket to seal on those.

Keep after it Johnny, gotta believe you can figure this one out.:wave:
 

Troll

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Last Subscription Date
08/10/2017
Re: My FIRST Kohler - 6R0Y61

I believe the unsupported cylinder barrel tops swell and shift when transitioning from cold to hot and back again. Probably the reason for head gasket failures. Worked on more than my fair share of Vega cars too.
 

JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

In my garage I have a security camera. Without realizing that the Kohler was in perfect view of the camera, I was able to extract a few seconds showing the purging of the water from the hydrolocked cylinders as well as a scare when the Kohler tried to automatically start for unknown reasons while my friend and I were looking over the motor shortly after purging the fluid from the cylinders. Sorry, no sound, only video.


Video showing Purging water in hydrolocked cylinders after removing fuel injectors. The fluid came out of each cylinder in great force and looked like vapor. The crud stuck to the ceiling on my garage:
https://www.youtube.com/watch?v=96ea5zygkys&feature=youtu.be


Video showing the Kohler automatically starting for reasons unknown after purging water in hydrolocked cylinders. Keep your eye on the genset's fan blades and when it tries starting you will notice when the blades turn. This happened several times during this short video:
https://www.youtube.com/watch?v=IqL9t9_P5PQ&feature=youtu.be


JohnnyC
New Jersey
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Re: My FIRST Kohler - 6R0Y61

Welcome to the Kohler club, Johnny! :D I have... Eight? Or nine? Something like that. :shrug: But my *newest* is 1965, IIRC, and I have yet to obtain any small diesels, so I can't offer much help beyond moral support. :O

Keith
 
Last edited:

Mikey NY

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Last Subscription Date
02/28/2016
Re: My FIRST Kohler - 6R0Y61

good to see you on the Kohler side here. It looks like you may be into the most challenging project yet. Thank God this one was a freebie. :uhoh:. Looks real nice though. Hope your having fun
 

PopsGarage

Subscriber
Last Subscription Date
10/03/2019
Re: My FIRST Kohler - 6R0Y61

Johnny, it is not dark on that side just not green, Your little yanmar looks like it was run hard and put up wet what a mess but I know that in a very short time it will be torn down and rebuilt to your exacting standards,

Bob
 

I like oldstuff

Registered
Last Subscription Date
11/09/2015
Re: My FIRST Kohler - 6R0Y61

Working on hundreds of engines over the years I have never seen anything as gunked up as that. Take it outside and go at it with the hose. Good luck with cleaning the radiator and the depths of the block! As the top end was totally clean that tells me it also was crudded. And perhaps the internals are still filthy. I'd pull the pan to be sure.
 

JohnnyC

Subscriber
Last Subscription Date
07/13/2019
Re: My FIRST Kohler - 6R0Y61

Working on hundreds of engines over the years I have never seen anything as gunked up as that. Take it outside and go at it with the hose. Good luck with the radiator!
That is the plan for today. Luckily I left the Kohler on my trailer, so I will hookup and tow it outside, cover all holes leading down into the crank case such as the push rod holes and cover the fuel injection pump, then blast out the coolant passages in to block. I'm not going as far as removing the freeze out plugs since I think it may not be needed. Water and compressed air should be good enough.

At this moment I am starting the day off with my customary 1 pot of coffee (yes an entire pot), then I have a few house chores to do, then it's off to my playground to play with the Kohler. Updates will follow later today.

JohnnyC
New Jersey
 

1tech

Registered
Re: My FIRST Kohler - 6R0Y61

... more pictures -


The third picture shows a small something that I pulled out of the coolant passage way. It felt like one of those bad experiences when you have toilet paper failure while wiping yourself on the porcelain pony.



JohnnyC
New Jersey
That almost looks like one of the frost plugs that rotted out of the block of my Kubota B6000. Also behind the water pump (hmmm....?) If the oil was that clean wonder if it was flushed and refilled without doing the cooling system as well. Excellent job on diagnostic step by step :salute:
 

I like oldstuff

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Last Subscription Date
11/09/2015
Re: My FIRST Kohler - 6R0Y61

1tech, not to thread morph, but I also have a B6000 as a daily driver. I did the camshaft plug thing and generally went through the engine for a freshen up this year. Can't get the injectors out though. Any ideas?
 

1tech

Registered
Re: My FIRST Kohler - 6R0Y61

Understand, I like oldstuff. I'll PM you the links that helped me if I can find them again. I ended up wire brushing the injector bases and soaking the threads in ReleaseAll for about a week and a half.
 
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