3 fried pistons

[spanky2002]

first trip after breakin (2.4 bridgeport), good water pressure, but head temp only marking 105 degrees. opened her up and 1,2,3 fried. after motor locked up, felt heads to see if hot and were not. does this sound like a lean condition?

[stvhelm]

efi or carb? sounds lean

[half fast]

Who's piston's in the motta? I could guess?

[Rickracer]

And it was cold seizure. :(

[us1]

How was it broken in.

[spanky2002]

NOT SURE WHAT PISTONS ARE IN THE BLOCK BUT THE BREAK-IN LASTED 12 GALLONS AT HALF TO 3/4 THROTTLE. IT'S AN EFI. PLUGS LOOKED GOOD AFTER BREAK-IN

[us1]

You have to break it in for 10 hours not 12 gallons. 12 gallons of gas at 3/4 throttle is about 1 to 1 1/2 hours. Does it also have steel sleeves in it?

[spanky2002]

no steel sleeves, that is till now. only on one cylinder though. why so long on the breakin? i thought the 280 motors had an internal timer of 2 hrs before allowing the engine to be opened up?

[--1fast one--]

Why so long on break-in so your pistons will not sieze. You also have to allow time for your rings to seat in. 2 hours, plus cooler tempertures will not do it.

[us1]

The 280s are set up to stop people from going over a certain RPM for a 2-hour period. This is the most critical time of break-in. After that you can bring up the RPM to a higher limit for a short time NEVER putting a strain on the motor or using full throttle for an extended time. This time period is usually about 10 hours if you want the motor to last a long time.

[hydrostream1]

Is there another manufacturer besides wiseco and merc making pistons for these motors?I have had some problems with wisecos in the past on other two stroke motors.

[Rickracer]

They are NOT forged, they are hypereutectic, so upper RPM range is 7200~7500. Of course they'd need to machined to work in the BP block, (flats and cooling holes). Ask Comp King, he just put a set in his BP. :cool: