J
2007 M8 PG Turbo, Attitude control box, 9 lbs of boost, Avgas
I went riding last Saturday, had a great ride, machine was running great.
Probably put 20-30 miles starting and stopping the sled plenty, shutting on and off before I pulled up to the group, let the machine idle down, and then shut it off.
Only thing was after this time shutting down it would not re-start.
I put new plugs in on the hill, pulled plugs and turned it over and had some gas spray come out. I was getting both fuel and spark, but could not get the thing started. It pulled over a little funny and I figured something happened in the top end / crank.
I got towed home and brought it into my garage. I pulled the plugs, unplugged the fuel pump, unplugged the injectors, and pulled and pulled. So much gas came out of the spark plug holes my machine was entirely covered in gas (note to self for next time, don't leave spark plugs hooked up to wires, good thing I had my compressed air gun handy, otherwise I'd be asking about garage building ideas!). I pulled for 3-4 minutes spewing massive amounts of fuel. The crank must have been completely filled with fuel. I then put the plugs back in leaving the fuel pump and injectors un-plugged. It started up first pull and ran with no fuel pressure / injectors firing for over a minute!
I checked injectors, they are not sticking and do not leak a drop of fuel under full fuel pressure. The machine starts and runs great now in my garage. Compression is good, but machine has 3500 miles, so new pistons are going in tomorrow.
My question:
How on earth did this thing get so loaded up?
What can I do to keep it from happening again?
Is it possible all the gasoline in the crankcase hurt the crank bearings?
What is a Cat crank supposed to feel like when you turn it over without plugs in it? Mine has 12 distinct stopping points. Not hard to overcome, kinda feels like a DC electric motor going through the magnets. I'm not sure if this is normal or not. The crank just sort of moves in 30 degree increments. If you stop it between incriments, it moves to one. If I run the motor and stop it, the increments are in the exact same spots. It seems too consistent to be a bad bearing or something, but I didnt think the stator would be this powerful? Maybe it is and i'm just not used to it.
I went riding last Saturday, had a great ride, machine was running great.
Probably put 20-30 miles starting and stopping the sled plenty, shutting on and off before I pulled up to the group, let the machine idle down, and then shut it off.
Only thing was after this time shutting down it would not re-start.
I put new plugs in on the hill, pulled plugs and turned it over and had some gas spray come out. I was getting both fuel and spark, but could not get the thing started. It pulled over a little funny and I figured something happened in the top end / crank.
I got towed home and brought it into my garage. I pulled the plugs, unplugged the fuel pump, unplugged the injectors, and pulled and pulled. So much gas came out of the spark plug holes my machine was entirely covered in gas (note to self for next time, don't leave spark plugs hooked up to wires, good thing I had my compressed air gun handy, otherwise I'd be asking about garage building ideas!). I pulled for 3-4 minutes spewing massive amounts of fuel. The crank must have been completely filled with fuel. I then put the plugs back in leaving the fuel pump and injectors un-plugged. It started up first pull and ran with no fuel pressure / injectors firing for over a minute!
I checked injectors, they are not sticking and do not leak a drop of fuel under full fuel pressure. The machine starts and runs great now in my garage. Compression is good, but machine has 3500 miles, so new pistons are going in tomorrow.
My question:
How on earth did this thing get so loaded up?
What can I do to keep it from happening again?
Is it possible all the gasoline in the crankcase hurt the crank bearings?
What is a Cat crank supposed to feel like when you turn it over without plugs in it? Mine has 12 distinct stopping points. Not hard to overcome, kinda feels like a DC electric motor going through the magnets. I'm not sure if this is normal or not. The crank just sort of moves in 30 degree increments. If you stop it between incriments, it moves to one. If I run the motor and stop it, the increments are in the exact same spots. It seems too consistent to be a bad bearing or something, but I didnt think the stator would be this powerful? Maybe it is and i'm just not used to it.
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