sputter and back fire

[coondog78]

I have a 95 Maxum 1800 SR, the motor runs strong but after about an hour of running it begins to sputter and back fire, I have put new plugs in it and it did not fix the problem. The blower does not work and I would like to get a new one but do not know what kind I need. Can anyone give me some advice on these issues?

[shrew]

Backfiring is caused by unspent fuel being discharged thorugh the exhaust valves and igniting as it hits the hot exhaust system. You've already swaped out the plugs, which I would recommend as this could be caused by a cylinder not firing. I'd also look at swapping out the distributor, rotor and plug wires as well since these could lead to a similar siutation. These should be canged out periodically anyway. Finally, I'd make sure that the engine is timed correctly. Having an exhaust valve opening early could cause a situation like this as well.

[coondog78]

Thanks for the reply! I guess it was more of a pop not a backfire. I drained all the fuel, and replaced the fuel filter. The gas looked like apple cider, it was very nasty! The fuel filter had a lot of dirt and stuff in it. With fresh gas and a new filter she ran great! I'm going to go ahead and order a tune up kit with a distributor and rotor and get new plug wires I don't think it will hurt anything. Thanks for the help!

David Cooney
96 Maxum 1800 SR
"The Rubber Duck"