9.9 Four-stroke Question

[warhawk]

I have a Johnson (Bombardier)2002 9.9 four-stroke. Best engine I have ever had. Two questions: first, when I winterized it this past fall, I inserted the special flushing fitting to the lower unit (it is not a muff, but a screw-in device) and had the hose turned on. I started the engine and ran it for probably 30 seconds but noticed that no water was coming out of the check hole. That is because I forgot to tape over the cavity above the prop, as indicated in the manual. I did that, and restarted it to continue the winterization, and the engine ran fine, with water coming out of the check hole. QUESTION - did this do any damage at all to the engine? Second question - I troll with this motor - about 100 hours per year. How frequently does a four-stroke outboard need to be de-carbonized, if at all? THANKS!

 

[DJ]

Re: 9.9 Four-stroke Question

warhawk,<br /><br />I do not think you harmed the engine, but you may have slightly damaged your water pump impeller. It's probably due for a service anyway.<br /><br />You shouldn't have to decarb a 4 stroke.

 

[JB]

Re: 9.9 Four-stroke Question

Howdy, Warhawk.<br /><br />As DJohns points out, you may have damaged the water pump impeller.<br /><br />The flushing port is meant for flushing an engine that is not running. The water pump is not pumping and can be damaged by running in a dry housing. To keep the water pump working with the engine running, you need to use the muffs. That is how my '96 9.9 Johnny 4 stroke works.<br /><br />I agree that you should replace the impeller.<br /><br />Good luck.

 

[warhawk]

Re: 9.9 Four-stroke Question

Thanks for your responses. However, my 9.9 is not designed to accept muffs of any kind - the only way to run it out of the water is to hook up this fitting (or put it in a test tank). When I covered the screen that sits on the underside of the cavity plate (above the prop), the water came out of the check hole as it should, so it seems that I must have done it right (the second time). Final question - how much is a new water pump impeller (part and labor) and if I don't get it fixed right away, will there be any warning signs before it fails? THANKS AGAIN!