Bull 36 #1 Posted 23 hours ago Hello Everyone, My 1986 Wheel Horse KT417A (series 2) with supposedly 561 hours has been running well until just recently. I was cutting my lawn and after about an hour the motor started loosing power. I shut it down for about an hour and then restarted it and it seemed fine. The same thing happened a week later. When is looses power I can't restart it for a while. Now it doesn't seem to have the overall power it once had but it has been doing the job.The fuel filter has been replaced, gas is good, plugs fine, points and condenser replaced last year. I had an issue a couple of year ago where I had to free up the #2 valve. I scraped the head and that side was carbon free with no other issues. The #2 side compression reading is 70 lbs with the #1 side 54 lbs. The motor doesn't burn oil or smoke. Does anyone have any ideas on what to do next. Regards, Bob Share this post Link to post Share on other sites
pfrederi 20,704 #2 Posted 23 hours ago (edited) That is not much compression especially #1. Carbon on the valve??? Do the spark plugs look about the same. Edited 23 hours ago by pfrederi Share this post Link to post Share on other sites
Bull 36 #3 Posted 23 hours ago Hi Paul, The #1 plug (54 lbs) just a little dark but not to bad. Share this post Link to post Share on other sites
pfrederi 20,704 #4 Posted 23 hours ago 6 minutes ago, Bull said: Hi Paul, The #1 plug (54 lbs) just a little dark but not to bad. Yeah Typo on cylinder # but 54 is bad 70 isn't; that great, Can you do a leak down test they provide more info than a compression test. 1 Share this post Link to post Share on other sites
oldlineman 1,738 #5 Posted 23 hours ago Have you replaced the air filter, I had my 1989 414-8 several years ago actually shut down while mowing and it turned out to be a very dirty air filter ( dandelion seeds ). I try to change the filter regularly, but lost track of time. 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 12,283 #6 Posted 23 hours ago Is it easy to check the valve clearances? Share this post Link to post Share on other sites
pfrederi 20,704 #7 Posted 23 hours ago 1 minute ago, gwest_ca said: Is it easy to check the valve clearances? Unfortunately Valves are not adjustable on KT17 but checking it could point the way Share this post Link to post Share on other sites
Bull 36 #8 Posted 23 hours ago To All, The air filter is good. I was wondering if trying to de-carbon with water might help on the lower compression cylinder. Share this post Link to post Share on other sites
Bull 36 #9 Posted 23 hours ago If it is determined that a rebuild of the motor is required are there arts available for this motor? Regards, Bob Share this post Link to post Share on other sites
pfrederi 20,704 #10 Posted 22 hours ago 5 minutes ago, Bull said: If it is determined that a rebuild of the motor is required are there arts available for this motor? Regards, Bob Can't comment on water decarboning.. I have 3 KT 17s and 1 Magnum 18 and I love them but after over hauling my Mag18 I decided I would never do it for a KT17. Some parts are harder to find and they are not cheap... and machine shop work is twice as expensive (2 of every thing). It was a few years ago just under $900. Sure now with higher machine shop work and parts you are over $1000. Share this post Link to post Share on other sites
peter lena 9,909 #11 Posted 5 hours ago BULL @ KT17A regularly refer to this on engine recovery , engine varnish is like a reheatable glue , it also comes back to where it was hiding in plane site , been using , RISLONE ZINC , 2 oz per qt of oil , bottle specs , for years , also like valvoline vr 1 , 10 /30 oil made for flat tappet cams , run in on a seperate gallon of heavily treated fresh fuel , don,t scream the hell out of it , just let run , and notice the gradual running ease , , thats the varnish cutting / breakdown , this also kills heavily varnished piston rings , none of my engines smoke , at all . get some hours on it , and do a hot oil flush / drain . what ever I refer to , been doing it for years , no issues , also add STA BIL to every bit of my gas , no fuel hose break down , sound familiar ? thats another great spot to eliminate , think I would try the varnish removal first , its always there , hot oil zinc , will break that down , i,m in ledyard ct , pete Share this post Link to post Share on other sites
Bill D 2,904 #12 Posted 4 hours ago (edited) Are you running the compression check with the choke off and the throttle wide open? If not, you'll get some very low compression numbers. Also, anytime I change points I set the timing with a timing light. If the timing is off, it can cause overheating. Compression that low may be a valve issue. According to the book 90 psi is the low spec for that engine. Edited 3 hours ago by Bill D Share this post Link to post Share on other sites
Bull 36 #13 Posted 2 hours ago Hello Everyone, I ran the compression test with the choke off and a throttle wide open. I also use Sta-Bil the fuel. I also have been using Shell Rotella 30w for engine oil. I will try the the Riselone Zinc and see if that helps. Thanks everyone Share this post Link to post Share on other sites
Bill D 2,904 #14 Posted 1 hour ago Have you checked for leaking or blown head gaskets? Any video of it running? Share this post Link to post Share on other sites
peter lena 9,909 #15 Posted 16 minutes ago @Bull change that oil over to a 10-30 , heats up faster and temp change up , enhances , cleaning function , think that 30 wt , with existing varnish , never lets it work with the hot flinging temp it needs . when I started , using , rislone zinc , the oil color change and condition of the oil was , really used up in filth , never looked back , it was a change that made for easier running , that valvoline VR1 10-30 , is made for flat tappet cams , just my similar experience , pete Share this post Link to post Share on other sites