Is the core bad?

[d_glover25]

Okay, I just replaced a 717 engine on a 2001 Sea Doo GTI and I'm having problems starting. It has a brand new starter and I just replaced the battery. It turns over slowly and jerky and makes a clunking sound. When I take the plugs out it turns over strong and smooth. I've sanded the main ground wire connection and tried bypassing the silenoid with no luck. All connections are tight and I don't know whats wrong. Should I send it back?

 

[Jeff Walkowiak]

Re: Is the core bad?

I assume you purchased a sbt engine, when you removed the magnet bucket in the front cover did you mark the exact location so that you could put it back on the flywheel in it's proper place if not your timing will be off by 90 degrees, also the key on the crank shaft must be in correctly, also timing the rotary valve is really important and a bit tricky.
if you purchased a used engine then god only knows what's wrong but by the description you give it could have a bad rod bearing or crank, etc

 

[d_glover25]

Re: Is the core bad?

It is SBT. What do you mean by magnet bucket? Are you talking about the magnets inside of the flywheel? This would be hard to get wrong right? The wires attached to them only allow for a little slack and theres a groove that the wires must go. If I remember correctly there is only 4 screws holding this on. If it was in there wrong the wires wouldn't reach. The timing has been doublechecked and I'm pretty sure its right. One thing I did notice while rechecking the timing was water under the rotary valve cover and inside the intake manifold and ports. For the record, I've never run water thru the engine because I've never got it to turn over properly much less start. How could this be? Is it condensation? Could SBT have left water in it? Do you have any experience with bad engines from them? Could the water be causing this problem? Could water cause a bad crank or rod bearing?

 

[Jeff Walkowiak]

Re: Is the core bad?

the magnets that operate the stator can go in wrong,, however water should not be in the crank case at all,, and yes I had a bunch of bad 787 engines from s b t they hated to see me walk in the front door with my short block, they are pretty close to me.
the part I was talking about bolts to the flywheel with small allan bolts and it has magnets that spin inside the stator windings that can be off by 90 drgrees and the ski will not run

 

[Jeff Walkowiak]

Re: Is the core bad?

I would check this water in the crank case and see if it isn't actually fuel and not water,, I have seen carbs leak fuel in to the crank case while sitting and hydrolock the engine, there is no place for water to come from if you never attached a hose to the engine,, if it is water then you had to turn on the hose with the engine not running and fill the crank case from the hose.

 

[d_glover25]

Re: Is the core bad?

I'm pretty sure it was water because it beaded up, fuel mixes with oil right? It wasn't much. The fuel valve was never turned open too. Anyways, another core is coming with the warranty. will post an update. Thanks man.