1988 johnson 70hp cooling concern

[ebuchho]

My Johnson 70 runs great has new impeller and t-stat no stream from water indicator, relocated hose for indicator to top of engine still no stream hose and passages were cleared still no stream but a lot of water from exhaust ports on midsection and never gets hotter than 150 and doesn't overheat should I be concerned

 

[Bosunsmate]

Re: 1988 johnson 70hp cooling concern

I would be as an overheat normally means an expensive and time consuming rebuild.
How do you know it doesnt overheat? Have you run it for a while and checked it with a temp gun at idle and varying speeds?

 

[ebuchho]

Re: 1988 johnson 70hp cooling concern

I check temp with ir temp gun and have gauge for temp ,was wondering if excessive salt buildup it is an 88 Johnson (oldie)
Ran 5 hrs all day today ran great no water from indicator temp 150 wot 120 just above idle

 

[Bosunsmate]

Re: 1988 johnson 70hp cooling concern

Have you tried removing the thermostat housing and seeing if water spurts out of there at pressure?
Since its up the top of the engine and your telltale outlet is at top of engine, if your thermostat is getting wet so should your telltale.
Did you try temp at idle or only just above idle?

 

[ebuchho]

Re: 1988 johnson 70hp cooling concern

Have you tried removing the thermostat housing and seeing if water spurts out of there at pressure?
Since its up the top of the engine and your telltale outlet is at top of engine, if your thermostat is getting wet so should your telltale.
Did you try temp at idle or only just above idle?

I'm going to remove t stat housing and see water circulating and maybe remove cylinder cover and inspect for build up will updaye soon thanks for all advice