Salta al contenuto principale

Repair information and troubleshooting for Craftsman-brand riding lawnmowers.

556 Domande Visualizza tutte

Backfiring when starting possible causes

What would cause this motor to backfire when starting?

Risposto! Visualizza la risposta Anch'io ho questo problema

Questa è una buona domanda?

Punteggio 5
1 Commento

erniedillon192, check your timing. The how to will depend on what model your mower is and what engine it has. It is possible that your timing is off due to a deformed flywheel key etc.


Aggiungi un commento

1 Risposta

Soluzione Prescelta

backfire is a result of half burned, hot exhaust finding oxygen to finish burning. I'd change the spark plug first. I'm guessing its also hard to start or does it just do this when the engine has been running?

Questa risposta è stata utile?

Punteggio 3

4 Commenti:

Yes it is hard to start beside the plug what else would cause backfire?


somehow your air/fuel mixture isn't right. Specifically would be hard to predict without messing with it. Its possible its not getting enough fresh air to support full burn in the cylinder, When did you change the air filter last?

Next I'd have a look at the carburetor, take off the bowl and see if its all gummed up with crud, if so clean it. If its still giving trouble, you might need to give the carb a good cleaning, which mostly sucks so because I'm lazy I'd try to run some barryman's b12 through it and see if that fixes it first.


Thank's will try that definitely grateful I'll get back later this week if I still have this problem again Thanks


My craftsman rider mower back fires thru the carb and will not start .I've checked the shur pin Good, have spark and plug gets wet . When start fluid applied it pops back thru carb . I feel suction thru carb so compression is decent. I've removed the fuel pump to eliminate that issue still same . Next I'll hot wire to bypass all electric, possibility issues . Could it be that the. Timing is off some how or ???? Just will not start . It's a day 4000 modle number 31p777 code 04332e1 hp 18.5


Aggiungi un commento

Aggiungi la tua risposta

erniedillon192 sarà eternamente grato.
Visualizza Statistiche:

Ultime 24 Ore: 8

Ultimi 7 Giorni: 77

Ultimi 30 Giorni: 381

Tutti i Tempi: 50,014