Docwheelhorse 2,660 #1 Posted February 28, 2009 Hello all and YES I DID A TOPIC SEARCH and found nothing to help. I recently put a new head gasket on my Kohler 14 K and found that the spark plug was only long enough to engage about 1/2 the threads and the other half was carboned up. I generally don't pay much attention to the plugs... I.E. I screw in the typical Champion J8C or NGK or ??? Plug that I have on hand. OKAY--everybody can throw me a beating now. Anyways--I attempted to find the correct plug at Walmarts, Kmarts, Sears etc.... by using there book. None of them list a K as they must be too old now I looked the plugs over on the shelf and they all seem to have a 1/2 inch reach or so. Nothing looks longer than what I already have. Yes I could go to the dealer but I didn't want to spend over $5 per plug... So what is the correct plug and where could I get a box of 12 or even 24 to leave on the shelf for my fleet of K's? I do prefer NGK over Champion but will try all of them. and Thanks Tony Share this post Link to post Share on other sites
TT-(Moderator) 1,131 #2 Posted February 28, 2009 This ought to help. Engine Share this post Link to post Share on other sites
Docwheelhorse 2,660 #3 Posted February 28, 2009 Thank You Very Much I am going to print it and staple it to the wall of my garage. Tony Share this post Link to post Share on other sites
Sarge 3,463 #4 Posted March 1, 2009 Uh, no offense but... Those are nearly all "short" plugs , wonder why none are the 9/16"-3/4" reach? Last time I put a plug in the Kohler I used an old one out of the Samurai , seemed to match enough on length compared to the Champion that was in there . Sarge Share this post Link to post Share on other sites
Docwheelhorse 2,660 #5 Posted March 1, 2009 Ummmmm..... Now that I think about it & re-read the post Sarge is right! All of those plugs will still leave about 1/2 of the threads in the head not used. A 3/4" reach plug would be about right---now what Or is that the way Kohler wants it and just keep on truckin'! Tony Share this post Link to post Share on other sites
TT-(Moderator) 1,131 #6 Posted March 1, 2009 The electrode on the plug must not protrude into the combustion chamber area on these engines. This might not be an issue on the heads with a centered spark plug hole, but the later heads placed the spark plug directly over the exhaust valve for better (more complete) combustion and the valve could potentially hit the ground electrode and actually smash the gap closed. If you install a plug with a longer reach, make sure you turn the engine over by hand first. Bent valves and smashed spark plugs aren't good for these engines. :thumbs: Share this post Link to post Share on other sites
Sarge 3,463 #7 Posted March 1, 2009 I wondered about internal clearance, just don't have any loose heads here to check. All my stuff is pre-'68. Sarge Share this post Link to post Share on other sites