Kohler Magnum18 Valves NLA Issues

[pfrederi 17,116]

My minor project to replace sheared/stripped engine tin bolts has expanded and not in a good way. My 418 is the newest Horse I have and while i am used to running into the dreaded NLA note for parts on my older Horses i thought that a 1986 engine would still have parts available...Wrong.  Intake and exhaust valves for Magnum Twins (and KT17s) are NLA.

 

Now this engine was working fine.  The hour meter which didn't work when I got it showed 1200 hours but the wear on the front tires and other wear indicated many more hours.  But she doesn't smoke make knocking noises and has good power.  Thus when I pulled the heads to get better access to the broken tin bolts and to do a decarboning I found 3 valves in good shape but one exhaust valve was seriously eroded.  Seat looked good so I went in search of an exhaust valve.  In 1988 Kohler changes the valves in Magnums from a 45 degree grind to 30 degrees. Then found that all the valves 45 degree and 30 intake and exhaust are NLA.  Before they dropped them they also changed the replacement valve number to 8275511s which included a valve seat.  Got a NOS one from Ebay.  You get a 30 degree valve and an unfinished valve seat with instructions to remove the old valve seat with Kohler Tool 11726...NLA then press in the new insert with Kohler Tool 11811 also NLA  (seeing a trend here????).  Then grind the new seat to 30 degrees ( do not have a valve grinder).

 

Frustration level was rising when i thought there really isn't much difference between KTs and Magnums when it comes to internals  Dug out some valves i had salvaged from a blown KT 17.  They were the same diameter and stem size.and were 45 degree which matched my existing valve seat.  Had to file a bit off the stem to get the .010/.014 cold clearance.  Looks like it should work just fine...I hope.)

 

Lesson here do not scrap blown KTs salvage what you can as parts avaialbility for Kohler twins is evaporating. This included eh cast iron twins in the D series.their parts are hard to find also.

 

There are frequent discussions here about using OEM parts or after market in the K series singles.  Be glad you have a choice...  There also seem to be almost no after market Magnum parts.

Edited December 11, 2017 by pfrederi

[SPINJIM 1,978]

Thanks for the warning.  I have a 417 with the K engine, and a 418 with the Magnum.    Fortunately, both have hours under 900.   I'm also disappointed in Kohler for discontinuing recent parts.

    Jim

[WHX?? 46,675]

Replacing the valve seat and grinding the replacement should be a piece of cake for a machine shop? Are you saying those kits are NLA and just lucked out on ebay?

[953 nut 51,464]

Check out Brian Miller's parts pages, he has what you need.

http://gardentractorpullingtips.com/a1miller.htm#valves

1-3/8" Diameter Intake Valves for Kohler engine models K241/M10, K301/M12, K321/M14, K341/M16, K482, K532 and K582. Dimensions - Head diameter: 1-3/8"; Length: 4.640"; Stem diameter: .3095"; Face angle: 45º.

• High quality aftermarket ordinary long lasting intake valve. Replaces Kohler part # 235008-S. $26.00 each, plus shipping & handling.
• High quality aftermarket Stellite (extremely hard and long lasting material) intake valve. Replaces Kohler part # 235582-S. $26.00 each, plus shipping & handling.
• OEM Kohler ordinary long lasting intake valve, part # 235008-S. $47.48 each, plus shipping & handling.
• OEM Kohler Stellite (extremely hard and long lasting material) intake valve, part # 235582-S. $95.63 each, plus shipping & handling.
• Reground Valve, used and in excellent condition. $10.00 each, plus shipping & handling. (When available.)
• Grind 30º angle on intake valve face to improve engine performance or for high performance use. (Seat must be recut or reground at a 31º angle to match angle on valve face.) $5.00 extra.

 

---

1-3/8" Diameter Exhaust Valves for later model K321's/M14 (suffix "D" and later), K341/M16, K532 and K582 (for K582 after serial # 9165450). Dimensions - Head diameter: 1.373; Length: 4.639; Stem diameter: .3075; Face Angle: 45º. FYI - Regardless of what you've heard, running an engine without a muffler or some kind of exhaust system will NOT cause the exhaust valve to burn. This is an old mechanic's myth that got started many years ago when poor quality metal was used to make exhaust valves. Technology in metallurgy and quality of exhaust valves have advanced a lot in recent years.

• High quality aftermarket Stellite (extremely hard and long lasting material) exhaust valve. Replaces Kohler part # 237672-S. $26.00 each, plus shipping & handling.
• OEM Kohler Stellite (extremely hard and long lasting material) exhaust valve, part # 237672-S. $67.09 each, plus shipping & handling.
• Reground Valve, used and in excellent condition. $10.00 each, plus shipping & handling.

Edited December 11, 2017 by 953 nut

[pfrederi 17,116]

48 minutes ago, WHX12 said:

Replacing the valve seat and grinding the replacement should be a piece of cake for a machine shop? Are you saying those kits are NLA and just lucked out on ebay?

 

 

Yes

 

 

[953 nut 51,464]

Looking at Brian Miller's information the intake valves from a K241/M10, K301/M12, K321/M14, K341/M16 and exhaust valves from a K321's/M14 (suffix "D" and later), K341/M16, are the same as the ones for a KTwin (probably the MTwin too) with a 45* grind.   

Seems Kohler was as conservative as the ponds  when it came to using parts interchangeably.

[pfrederi 17,116]

12 minutes ago, 953 nut said:

Check out Brian Miller's parts pages, he has what you need.

http://gardentractorpullingtips.com/a1miller.htm#valves

 

 

Appreciate it.  The part number he has is for others pec numbers according to Kohler...But tehn it may work.  Current price is about 58.  Will have to look at teh measurements.  Hopefully my used one Iput in will work.  Note no after market...