2 replies to this topic

[jimd]

I pulled the engine and one of the piston bearings is shot. that created lots of collateral damage. Since the engine is 1997 vintage I ordered an entirely new short block and I am 50% complete with the installation of a new engine.

Seized - Challenger 1800 twin Rotax engines
Just had engine rebuilt last year at reputable SeeDoo dealer and it seized after about 20 hours.
Engine rebuilt in 2010 and engine ran fine. Winterized boat and both engines ran fine first time out. Rebuilt carbs and both still ran fine - boat was screaming. Second time out went tubing and blew the exhaust hose from tuned pipe to exhaust resonator also noticed that the top on the water regulator blew off - yes came apart. I replaced the hose and replaced water regulator with new regulator. Engine ran fine on the trailer also ran fine in no wake zone. I leave the no wake zone and get to 3/4 throttle and the starboard / rebuilt engine RPM's drop and it shuts down. I limp in on one engine after clamping the water intake on the starboard / dead engine. I let it cool and still no cranking - seized engine. I am wondering what could cause such a disaster? I thought the hose break was just due to worn old hose, the water regulator valve surprised me but it is an old boat. I have not pulled the head to look at the pistons yet. Can anyone tell me why this overheated condition might happen without warning? What does it mean when the water regulator valve blows it's top off?

[Kevin Leclair]

This is a very difficult one to diagnose remotely, it might be a good idea to have another SeaDoo technician look at the engine to determine what exactly is going on. Keep us posted.

[gint2]

not to hijack or resurrect a dead thread but has anyone used SBT engines?? I had a very similar problem as noted above and am thinking of just replacing the engine. Not familiar with these Rotax motors to try a rebuild/repair myself.