OMC 454 KC belt + exhaust hose problems

[concept 258]

Hi all,<br /><br />I am the owner of a ’92 Chris Craft Concept 258, with the OMC 454 King Cobra engine. The boat is used just a few days in summer, it remains the rest of time on a shipyard, the engine has not many hours, and it’s supposed to be very well maintained by good professionals.<br /><br />I have questions related to the problems I got this summer with the engine.<br /><br />First question : the engine destroys very quickly its power steering belt (in a few hours), this summer I had to replace the belt three times; Could this be related to the oil leak I got to the power steering pump ? Or something else ?<br /><br />Second question : this summer too, I was navigating (pretty quietly, 3500 RPM), when suddenly I had to stop the engine because of smoke and water vapour in the engine compartment. A hose of the starboard exhaust pipe had burst (in fact it was burnt). Fortunately, I don’t think the engine suffered from over-heating. Anyway, I got the boat out of the water, and motor boating was over for this year.<br /><br />The question : has any one an idea on the cause of the hose burst ?<br /><br />Of the course, the guys in charge of the maintenance of the engine will give me an answer, but in fact I am not sure they have any…<br /><br />In advance, thanks a lot.

 

[Elk Chaser]

Re: OMC 454 KC belt + exhaust hose problems

If the power steering pump is getting oil on the belt or sheave then that could ruin the belt fairly quickly. <br /><br />Sounds like you are running in salt water (ship yard) and the risers have ports that allow the water from the cooling circuit to exit out just ahead of the rubber exhaust hoses. In salt water these ports (and many many others) tend to get clogged up with deposits. Once the water flow is reduced the hoses can and will burn because there is no longer enough water to keep them cooled.

 

[Don S]

Re: OMC 454 KC belt + exhaust hose problems

Sounds like all the pulleys are rusty, which will eat up a belt very quickly.<br />You probably also need a new impeller or possibly manifolds and risers. They could cause the hose to burn with no water in them.

 

[concept 258]

Re: OMC 454 KC belt + exhaust hose problems

Very interesting, many thanks to you all.<br /><br />Not sure what is the "riser", is it the square part bolted on top of the manifold ? <br /><br />Is the impeller located into the riser ?<br /><br />Thansk a lot again.<br /><br />Nota : you are right Elk the boat is navigating in salt water (Mediterranean Sea).