Kohler K181 rebuild

[njdpo 8]

Hi all,

 

Back in 2011 you guys assisted me with getting my Commando 800 (engine K181) running properly (http://www.wheelhorseforum.com/topic/27577-wet-cooling-fins/#comment-234931 ).

 

6 years and many happy memories later that little K181 still runs – but she’s tired. She was tired when we got my issues all ironed out. I never did get around to dropping a new piston and rings in it. At this time the engine is down on power and blowing blue smoke - I dont want to blow up this motor if it can be refreshed.

 

I was thinking of sending the motor out – but I decided I will help my 14 yr old son (Willy) rebuild it. Hopefully I can keep the rebuild costs down – and Willy will learn something interesting.

 

a few questions for the group:

1. Is it possible to upgrade the K181 points ignition to electronic (without breaking the $bank$) ? The points are OK - but im wondering if the motor could benefit from an electronic ignition.
2. Are any of you aware of a document(s) of tips and tricks, and/or procedural documents for going through this rebuild process?  Thinking of things like:

• - Gunk motor off before removal & disassembly
• - Take picture of carb configuration before removal.
• - Paint inside of motor with this paint / - Paint outside of motor with that paint
• - Break in procedures.

 

Please let me know if you have any questions that I can answer up front.

Any advice you have is greatly appreciated – and yes I will be posting pics as we progress through this.

Thanks, Dave

Edited June 21, 2017 by njdpo

[pfrederi 18,104]

The K series single manual in the manual section here pretty much cover the topic.  You do not need to paint inside. Lots of pictures hlep failing memories.

[Achto 28,106]

7 hours ago, njdpo said:

Are any of you aware of a document(s) of tips and tricks, and/or procedural documents for going through this rebuild process?

 

Here is a Kohler manual.

I actually prefer an automotive coil & points set up. It allows you to work on the ignition system without pulling the fly wheel. Cleaning the engine off before you disassemble definitely makes thing more enjoyable. After disassembly you'll want to take your block & crank to a machine shop to have them measured so that you will know what parts to order, (over sized piston, under sized rod). The machine shop will then want the new parts before they do the machining. No need to paint the inside of the engine, unless you really want to spend the cash on Glyptal internal engine paint. Most enamels will work good on the out side of the engine. Take lots of pics while disassembling to help with assembly.

 

As for break in, return to use as normal remembering to keep you RPMs up so that the oil gets splashed around inside the engine as needed. Remember 3/4 & above throttle is actually better during break in. Change oil after the first 5hrs, then return to normal oil change intervals.  

[Shynon 7,474]

 

[JimmyJam 542]

K181 points ignition is a easier fix. Electronic breaker-less ignition (solid state) is tough to find and expensive to replace.

[RandyLittrell 3,886]

Kirk engines sell a point replacement. Here is a llink. 

 

 

http://www.kirkengines.com/

 

 

 

 

 

 

 

Randy

[njdpo 8]

Hi Shynon, 

 

13 hours ago, Shynon said:

 

Coincidentally I am a bit of a documentation specialist. 

I would be happy to proof-read that document for you ...  

 

and you can document the k161 and k181 - - - if I can fwd a few k181 pics to you. 

Thx - Dave

Edited June 21, 2017 by njdpo

[njdpo 8]

12 hours ago, RandyLittrell said:

Hi Randy - interesting link - http://www.kirkengines.com/

I see they sell electric fuel pumps - I installed one of these on my Case 444 (when the old mechanical pump died).

I like that the electric fuel pump can prime the carb bowl before cranking the engine ((( I  get instantaneous engine starts on the coldest of winters ))) 

 

My commando 800 - has the gas tank sitting above the carb and pump... ( I like this setup ) 

I'm afraid that a 40+ year old mechanical fuel pump could dump raw gas into the the sump and destroy a newly rebuilt engine (especially with the gas tank sitting above the mechanical fuel pump and carb).

 

QUESTIONS:

• Does anyone know if I can eliminate the mechanical fuel pump and just let gravity do the work ?
• Is it true - that a torn diaphragm in a mechanical fuel pump could contaminate (thin out) the sump oil ?
• If I dont need the pump - I guess I could just bypass it and go from tank to carb directly? (and eventually install a block off plate where the mechanical fuel pump was ) 

 

I could bypass / test this idea today - before I tear apart the engine. 

A vacuum fuel pump is another alternative - I guess. I don't think cold winter starts would be a problem either - since there would be ( little possibility ? ) of gas draining upwards to the tank above it. 

 

Thanks - Dave

 

 

 

 

 

Randy

 

Edited June 21, 2017 by njdpo

[pfrederi 18,104]

My lawn Ranger has had no fuel feed problems in 50 years...gravity is nothing if not reliable.

 

However the bottom of her gas tank is 1/2" higher than the carb fuel inlet.  i think if you measure the distance from the floor you will find  the bottom of your tank  is slightly below the carb inlet.  If you kept it mostly full it should work but it would die before the tank was completely empty.

[Achto 28,106]

36 minutes ago, njdpo said:

• Does anyone know if I can eliminate the mechanical fuel pump and just let gravity do the work ?
• Is it true - that a torn diaphragm in a mechanical fuel pump could contaminate (thin out) the sump oil ?
• If I dont need the pump - I guess I could just bypass it and go from tank to carb directly? (and eventually install a block off plate where the mechanical fuel pump was ) 

 

You can eliminate the factory pump, some have gone to an electric pump. Some have also replaced the old metal body pump with the new plastic body pump (all new pumps, even Kohler brand are plastic now). I personally rebuild the old metal body pumps and have not had any issues.

[njdpo 8]

1 hour ago, pfrederi said:

My lawn Ranger has had no fuel feed problems in 50 years...gravity is nothing if not reliable.

 

However the bottom of her gas tank is 1/2" higher than the carb fuel inlet.  i think if you measure the distance from the floor you will find  the bottom of your tank  is slightly below the carb inlet.  If you kept it mostly full it should work but it would die before the tank was completely empty.

 

I'll break out the tape measure and have a look at it - thanks ! 

If the risk of dumping gas into crank case through a bad fuel pump is real  - i think i can live with keeping the tank topped off 

Or replace it with a vacuum pump.

 

Thank - Dave