OMC KING COBRA SLIPPING

[peter_at_eyc]

I HAVE A KING COBRA STERN DRIVE ON MY CHRIS CRAFT CROWNE 232 WITH A 454 GMC ENGINE. As i approch planing speed (about 15-18 knots 3200rpm) the boat feels like a clutch slips, the motor revs high and the boat falls out of plane.<br /><br />First I inspected the prop and found aconsiderable buildup of barnacles. I cleaned the prop and stern drive (anti ventilation plate, etc.). On trial run, it still slipped out of Plane and revved.<br /><br />Next I removed the Propellor and found that the rubber hub had spun. Brought the Prop to be repaired and rubber hub replaced. Replaced propellor. On Trial run still the same problem.<br /><br />Next, I thought maybe I had not replaced the prop tight enough so I reinstalled it being careful to tighten the prop nut sufficiently. On trial....still not good.<br /><br />HELP PLEASE.....

 

[Boatin Bob]

Re: OMC KING COBRA SLIPPING

Peter...there is also a coupler between the engine and drive which can let go and cause the same symptoms however is not as easy to fix as the engine needs to be pulled to replace the coupler. Is your raw water pump in the drive or is it belt driven off the crank? If it's in the drive then sometimes the coupler slipping also shows as overheating because the water pump is also slipping.

 

[peter_at_eyc]

Re: OMC KING COBRA SLIPPING

Thanks Bob, I am not exeriencing overheating problems, how do I tell if the raw water pump is in or out of the drive?

 

[pvbearcat234]

Re: OMC KING COBRA SLIPPING

I had a problem similar to this that I just had fixed. My boat would sometimes get up on plane 20-25mph and then slow down on its own. Throttle down and back up sometimes resume and do the same thing. They found the seat on the jet in the carberator had some apart not allowing complete fuel flow when under a load.

 

[peter_at_eyc]

Re: OMC KING COBRA SLIPPING

Today, I marked the propellor hub and shaft, then ran the boat until the same slipping occured. When I checked the markings, they where out of alignment which means the propellor spun again. <br /><br />So, now I know the problem is a spun prop but I don't know what is causing it to spin out. Maybe it wasn't repaired properly. I'm hoping that is the simple solution so heregoes.... back to the prop repair shop to have the hub reset and then I'll try again.<br /><br />If anyone has any ideas why the prop would spin out, I would appreciate hearing them. I know the obvious reason is that I may have hit something twice in the same week, but I don't think that is the problem, we have pretty deep (> 25') waters in Narragansett Bay where I tested the prop.

 

[Bondo]

Re: OMC KING COBRA SLIPPING

I'd say the Prop Shop Didn't get it Right.......

 

[Skipster1]

Re: OMC KING COBRA SLIPPING

Bondo is right on the mark.<br />Considering the torque applied to the prop there HAS to be some sort of locking device - a shear pin or a lock washer or something - of some sort to prevent the prop from slipping.

 

[goodtimeguy]

Re: OMC KING COBRA SLIPPING

i would get the guys at the repair shop to warranty the repair, then go to a parts store, buy a new prop, and keep the repaired one for a spare.

 

[peter_at_eyc]

Re: OMC KING COBRA SLIPPING

THANK YOU EVERYONE!!!!!!<br /><br />I DID BRING IT BACK TO THE PROP REPAIR SHOP. IT WAS A FAULTY REPAIR. THEY ARE REPAIRING IT AGAIN WITH STRONGER RUBBER (USED FOR RACING). THE REPAIRMAN SAID THIS HAPPENS ONE OUT A HUNDRED REPAIRS WERE THE REPAIRED HUB DOESN'T QUITE FIX PROPERLY AND IT GETS SPUN A SECOND TIME.<br /><br />I GET THE PROP BACK TOMORRW AND WILL BE TESTING IT SOON.<br /><br />I'LL LET YOU KNOW HOW IT WORKS OUT.<br /><br />THANKS AGAIN.

 

[peter_at_eyc]

Re: OMC KING COBRA SLIPPING

YESSSSS!<br />It was the prop hub. The prop repair shop fixed it for free and put in a "racing hub" instead of the standard one. I installed the prop and everything is working o.k.<br /><br />Thank again everyone for your help.

 

[peter_at_eyc]

Re: OMC KING COBRA SLIPPING

By the way, the prop repair shop I used certainly is very honest and reputable. They not only fixed the prop for free the second time, but they also upgraded the repair to a racing hub at no extra charge. This kind of service is rare nowadays and I will recommend any others in my area use this shop. They are:<br /><br />BAYVIEW MARINE<br />781 Oakland Beach Ave.<br />Warwick, RI <br />• 401-737-2522