Hole in PTO piston

[Lloyd (ljm)]

 

 This is the engine that is in my Sportfire. It is the engine that was originally in my 80 440 Drifter.

 I sealed it all up. passd pressure test. Put it in sled, Drove about 1 mile and burned a hole in the piston.

 Any ideas why it burned?

[mswyka]

Ouch!  Did it run really, really, nice right up until the point where it quit?

I have seen that piston a few times on our 440 Invader and always just after it seems to fly like a jet.  And, each time we found an air leak on the inlet that allowed the engine to run lean.

[kawhead]

i say lean also.....what carb are you running?

[gixxer6]

Looks like it ran lean.  A lean condition is one of two things, too much air, or not enough fuel.  You did a pressure test, I would look at your fuel supply.  A plugged jet maybe?  Or a pinched fuel line? 

[Lloyd (ljm)]

Actually Mark it ran like crap before it burned.

 I know usually they never run better than just before they pop.

 Would you believe after it burned I still drove the sled home.(about 1500 feet)

Lloyd

[mswyka]

Glad you made it home.  I always had to get towed.  Very embarrassing.

[Lloyd (ljm)]

Back together and running much better today. Short run on probably our last sledding day