scotty 252 #1 Posted October 9, 2015 I was riding my b-80 around and it started running very bad and after a couple of.minutes it made a loud pop with a black cloud of smoke and something that looked like a fireball . now it wont start anyone know what could have caused this Share this post Link to post Share on other sites
kudzu3 323 #2 Posted October 10, 2015 Scotty, I'm not a mechanic but I believe I'd check the points first, may be a timing issue. I'm sure we'll hear from someone who knows soon, good luck with it. Share this post Link to post Share on other sites
slammer302 2,154 #3 Posted October 10, 2015 Could be a number of things but I would start with points and condenser Sent from my XT1080 using Tapatalk Share this post Link to post Share on other sites
Brian01 481 #4 Posted October 10, 2015 I'd have to agree, points are probably sticking Share this post Link to post Share on other sites
squonk 39,123 #5 Posted October 10, 2015 Does it sound normal when cranking? The smoke and fireball concern me Share this post Link to post Share on other sites
scotty 252 #6 Posted October 10, 2015 (edited) sounds normal turning over still has spark. i got it to start for a quarter of a second but doesnt really "start". Edited October 10, 2015 by scotty Share this post Link to post Share on other sites
buckrancher 2,678 #7 Posted October 10, 2015 check compression and fuel flow to carbBrian Share this post Link to post Share on other sites
953 nut 52,162 #8 Posted October 10, 2015 Black smoke and flames would indicate too much fuel. Since you have spark we can leave the points alone for now. The needle valve in the carburetor may have some junk holding it open, first thing to do is pull the carb. off and take a look (you will want to buy a kit to replace the seat and needle). Share this post Link to post Share on other sites
scotty 252 #9 Posted October 10, 2015 I tried a new set of points. that did not help. Ive had this for a long time and it just recently started acting up. im thinking it might be compression i do not have a compression gauge though. Fuel flow is no issue. Share this post Link to post Share on other sites
squonk 39,123 #10 Posted October 10, 2015 I would check compression. My first thought was a valve. 1 Share this post Link to post Share on other sites
Rob R 951 #11 Posted October 10, 2015 Hi agree with squonk you either stuck your exhaust valve or you have a Carb Issue..... my guess Valve. Share this post Link to post Share on other sites
Ed Kennell 36,034 #12 Posted October 10, 2015 Mike has it..... Fire + Fuel + Compression = A happy running engine. Smoke and fire from exhaust = .Exhaust valve stuck open Share this post Link to post Share on other sites
scotty 252 #13 Posted October 10, 2015 I took the head off the motor and the valves are all working. Im not getting any spark at my points though. Share this post Link to post Share on other sites
fast88pu 3,313 #14 Posted October 11, 2015 make sure coil is getting 12V with key on. my K181 just stopped out of the blue and it turned out to be a clogged air filter Share this post Link to post Share on other sites
953 nut 52,162 #15 Posted October 11, 2015 As a test you can disconnect the condenser and see if the spark returns, a shorted condenser will kill the spark. Share this post Link to post Share on other sites
squonk 39,123 #16 Posted October 11, 2015 You said it still had spark? 2 Share this post Link to post Share on other sites
Shynon 7,435 #17 Posted October 11, 2015 You said it still had spark? Share this post Link to post Share on other sites
scotty 252 #18 Posted October 11, 2015 Well i put in a new spark plug. Prefrederi brought a compression tester and plug tester and the compression was the same as a good running tractor i have. Running great with a new spark plug. Share this post Link to post Share on other sites
953 nut 52,162 #19 Posted October 11, 2015 So that was it, new spark plug and problem solved. Share this post Link to post Share on other sites
pfrederi 17,192 #20 Posted October 11, 2015 Glad to hear she is working again....I never buy Champion plugs anymore. Too many have failed to fire under compression. Share this post Link to post Share on other sites
scotty 252 #21 Posted October 11, 2015 Yup new plug and she runs great! I agree to many bad reviews on champions i prefer NGK plugs now. Hard to believe that could cause so many problems. 1 Share this post Link to post Share on other sites