kawimaniac2145 6 #1 Posted May 18, 2021 hey guys i have a problem with my tractor. i cannot get it to run it fouled out 3 plugs already, and when i get it to run it runs real rough. and both plugs have a purple spark instead of bright blue i can take pictures or videos of anything to help you guys out. just let me know what you want me to video or take a picture of any help would be greatly appreciated. i want to get mt tractor running good again thanks Share this post Link to post Share on other sites
lynnmor 7,487 #2 Posted May 18, 2021 The first thing to check is the compression. Fouling plugs may be coming from bad rings and no tuneup will fix that. If the compression is OK, then clean the carburetor. It is virtually impossible to diagnose ignition problems by the color of the spark, download the Onan Service Manual on this site and follow the tests there. Manual Share this post Link to post Share on other sites
kawimaniac2145 6 #3 Posted May 18, 2021 ok. i had cleaned the carb already and keep you guys informed. i desperately want to get this running good again. Share this post Link to post Share on other sites
kawimaniac2145 6 #4 Posted May 18, 2021 i got 120 on both cylinders. and looked inside the carb last night and was clean no obstructions. what should i do now any help's appreciated. Share this post Link to post Share on other sites
lynnmor 7,487 #5 Posted May 19, 2021 Compression is great, when you looked in the carburetor was it completely disassembled, or did you just peer down from the top? Share this post Link to post Share on other sites
kpinnc 13,124 #6 Posted May 19, 2021 (edited) Onans commonly have heavier carbon deposits on the heads- which is why the service manual says to manually clean them every 500-1000 hours. Even more true if multi-weight oil is used. I would follow what others have said about proper carb cleaning, and depending on what the hour meter says, also clean the heads. You will need a gasket kit for it, but the kit usually comes with exhaust and intake gaskets as well. As has already been said, you have great compression on both cylinders. Might as well do it right the first time, and keep that engine running another 25 years. Edited May 19, 2021 by kpinnc Share this post Link to post Share on other sites
kawimaniac2145 6 #7 Posted May 19, 2021 i would like to keep it running. so how do i clean the heads? Share this post Link to post Share on other sites
kawimaniac2145 6 #8 Posted May 19, 2021 is there supposed to be gas in the intake. and if not how do i fix it? Share this post Link to post Share on other sites
lynnmor 7,487 #9 Posted May 20, 2021 There should be no gas in the port, it is possible to get a small amount in while removing the intake if you don't keep it level. It appears that your carburetor needle valve is not stopping the flow, and needs to be inspected to find the problem. You may have gas in the oil if this was an ongoing problem, an immediate oil change may be in order. I would use paper towels to soak up the fuel. Share this post Link to post Share on other sites
kawimaniac2145 6 #10 Posted May 20, 2021 should i buy a brand new carburetor. and where can i get it. and how much? Share this post Link to post Share on other sites
lynnmor 7,487 #11 Posted May 20, 2021 1 minute ago, kawimaniac2145 said: should i buy a brand new carburetor. and where can i get it. and how much? No, just fix the one you have, it might not take much. Onanparts.com has kits and cheap ones can be found on eBay. If it is simply dirt holding the needle open, then you may need nothing. A bad float is also a possibility. If you disassemble and show us the innards, we might be able to guide you from there. Work clean and carefully. Share this post Link to post Share on other sites
kawimaniac2145 6 #12 Posted May 20, 2021 i think i may have figured it out i will keep you guys posted Share this post Link to post Share on other sites
kawimaniac2145 6 #13 Posted May 24, 2021 the engine runs great so smooth. i took the float where the needle attaches to and bent it down aa little and hooked my vacuum gauge down a little bit and it worked beautifully thanks everyone so much from the bottom of my heart that helped me. i will put a youtube video up for you guys. 1 Share this post Link to post Share on other sites
