sydgross 0 #1 Posted August 2, 2012 I have a bad oil sentry pressure switch on my '86 417-A. I can't find an original pn for it. Can anyone direct me to an interchangeable part? Share this post Link to post Share on other sites
BOWTIE 226 #2 Posted August 3, 2012 HELLO, CAN YOU SEND ME PICTURE OF SWITCH? WHAT DO MEAN BY THE PIN IS THAT THE ELECTRICAL CONNECTOR. I CAN USUALLY COME UP WITH COMMON REPLACEMENT. THANKS BOWTIE@COLUMBUS.RR.COM BOWTIE IN OHIO Share this post Link to post Share on other sites
tunahead72 2,543 #3 Posted August 3, 2012 I think sydgross meant pn, as in part number. Share this post Link to post Share on other sites
sydgross 0 #4 Posted August 3, 2012 Part number is correct. The part appears to be nothing more than an oil pressure switch like those on automotive engines. It threads into the engine case with a 1/16" NPT. I have seen Kohler oil sentry parts for different engines listed at $42 which breaks down to about $10 for the part and $30 for the OEM name. Share this post Link to post Share on other sites
bowtieguy 334 #5 Posted August 3, 2012 Back in 07, I bought a 417-A at an auction....engine would not run so I thought it was probably a fuel problem....got it home and discovered that someone has replaced the oil pressure switch with an automotive pressure switch...AND the wire going to it was NOT connected. I connected the wire and oil light came on and stayed on....not good...engine would turn over but not run...so I figured I just blew a bunch of money on a junk engine. At the time I was not aware that this series II engine carried high oil pressure. Not knowing exactly what to do, I ordered a Kohler oil switch from my Toro dealer...removed the automotive switch and installed the Kohler switch....engine started, red oil light went off ....wow, sweet running engine! Short of story....made me a believer to use OEM parts once in a while (like using the correct WH belts instead of cheap aftermarket belts). I can not verify that Toro sold me the correct switch....but here is the P/N as marked on the invoice (and Kohler package)....25 099 27-S ...invoice price was 7.76 each Share this post Link to post Share on other sites
sydgross 0 #6 Posted August 3, 2012 Thank you bowtieguy, that is exactly what I was looking for and the price is in keeping with the market. I agree with you, on many OEM parts there is no substituting without compromising quality. However, I have competed with OEMs for most of my life in the turbomachinery market. Without competition, their prices for spare parts can be obscene. Share this post Link to post Share on other sites
KC9KAS 4,744 #7 Posted August 4, 2012 Without competition, their prices for spare parts can be obscene. Yes, a little competition keeps everyone "honest" on their prices. Share this post Link to post Share on other sites
BOWTIE 226 #8 Posted August 4, 2012 HELLO, I SEE YOU GOT A LOT OF SUGGESTION. IF YOU GO WITH THE AUTOMOTIVE SWITCH PART NUMBER IS (PS15) STANDARD MOTOR PRODUCTS. IT IS A COMMON SWITCH FOR INLINE 6 CYLINDER CHEVY'S FROM THE 60'S-70'S. A 250 CUBIC INCH. I USED ONE IN MY 1999 CH14S KOHLER. THE SWITCH TURNS OFF THE LIGHT AT 3-7 PSI. THE THREADS IS 1/8" NPT GOOD LUCK BOWTIE IN COLUMBUS Share this post Link to post Share on other sites
bowtieguy 334 #9 Posted August 4, 2012 But remember, the series II engine on a 417-A carries about 35 psi oil pressure. (I think I'm correct with that statement)....I thought I was wrong one time but I was mistaken!! Share this post Link to post Share on other sites
BOWTIE 226 #10 Posted August 5, 2012 Bowtieguy, I don't know what kind of pressure my 1999 CH14S carries. The switch I used was for automutive use. So it can handle pressure up 60 or so pounds. I have never heard of 1/16" national pipe thread on a oil switch. Bowtie in Ohio Share this post Link to post Share on other sites
sydgross 0 #11 Posted August 7, 2012 You are correct about the sensor NPT, it is 1/8". The block is drilled and tapped to 1/16" and has a reducer installed to go from 1/8 to 1/16". Thank you all for your responses. They have been helpful and informative. Share this post Link to post Share on other sites