1977 Johnson 70 hp Impeller

[kellyart]

I have a 1977 Johnson 70 hp outbourd that has been setting for two years.<br />How can I tell if the impeller is working ?<br />I have ran it with muffs on but I'm not sure where the cooling water should exit from.

 

[dakk1]

Re: 1977 Johnson 70 hp Impeller

kellyart<br /><br />I would change it regardless. Then you'll know. Impellers are cheap and rebuilds expensive.

 

[kellyart]

Re: 1977 Johnson 70 hp Impeller

Thank you Dakk1 for the advice, I think I wiil put in a new impeller.<br />Now how will I know if the new one is working.<br />Is there some vent hole water will come out of only when the impeller is pushing enough water?

 

[dakk1]

Re: 1977 Johnson 70 hp Impeller

kellyart<br /><br />Yes there should be a "tell tale" behind the motor usually below the powerhead. Some motors won't show much on the muffs, others will. On my motor, with the cowling off, I can see the water hose going to it.

 

[Walker]

Re: 1977 Johnson 70 hp Impeller

1977's didn't have a tale-tell. Look for water coming out of the prop and maybe a little spray coming out of the exhaust holes in the midsection. Put your hand on the heads and if they get so hot you can't keep your hand on them for at least 4 or 5 seconds then its getting too hot. The heads will get rather hot before the thermostats open up.

 

[kellyart]

Re: 1977 Johnson 70 hp Impeller

Thank you Walker<br />I haven't been able to find a tell tail and now i know why.<br />There is a little water coming out of the exhaust vents so that is a good sign<br />Thanks again