1980 Mariner M-90 hp overheat sensor, I think

[Rick Stevens]

I bought this older engine and am going through the process of getting it running and There is an l shaped brash fitting in the head cover. I am thinking it is the overheat sensor but it has a vacuum hose hooked to it and it isn't connected to anything. Would someone know what this is and where it hooks up to? Thanks a bunch for any help ya can throw my way!!


This is a 6 cylinder tower of power engine..

 

[Rick Stevens]

It is the 6 cylinder tower of power..

 

[racerone]

I would say it is for a water pressure gauge.------Post the picture of it.

 

[Rick Stevens]

[No message]

 

[Rick Stevens]

SO I assume this is the over heat sender via high water pressure?? Thanks

 

[racerone]

Water pressure gauge.-----The hose should go to a gauge at the helm.----Likely that hose was cut where it exits the lower cowling.----A wise man would use this and install a gauge.

 

[Rick Stevens]

LOL Don't know about wise but I will heed your message and install the gauge for it. Thank you very much!!

 

[Faztbullet]

You need a gauge that reads a max of 15psi...engine at idle will only have 1-3 psi and 9-11psi at WOT

 

[Rick Stevens]

You need a gauge that reads a max of 15psi...engine at idle will only have 1-3 psi and 9-11psi at WOT

Alright, thanks for that,, I am looking at them right now. I had 2 old big ones off the twin mercs that come off this boat. Of course I didn't keep them LOL.......

 

[Rick Stevens]

[No message]

 

[Rick Stevens]

This is the boat I am restoring 1959 20' Reinell cuddy cabin. Amazing all they got into the cabin, enclosed head and all in a 20'er. I just love the lines of this boat. My tower of power should be perfect for it. I got this boat for free, LOL and I have so much work into it already, Had the rebuild the whole transom, the whole floor system and everything in between. I just love the older boats.All the original glass is there just 2 BB holes.

 

[Faztbullet]

Hopefully there is no "hook" in bottom where it has sat on them rollers for years

 

[Rick Stevens]

Hopefully there is no "hook" in bottom where it has sat on them rollers for years

I checked there isn't.. the bottom is pretty strong, the sides not so LOL........... Thanks

 

[Rick Stevens]

This is the motor in ? She will be nice when done. Just changed the impeller and housing and gaskets. I fogged the cylinders last night to start the de carb process on the rings. I haven't heard it run yet but the compression check was good. 150-165 PSI........... Not bad for sitting for many years...

 

[The Force power]

You'll be happy when it's all done & enjoy a nice solid boat
Nicely done

 

[Rick Stevens]

I bought this older engine and am going through the process of getting it running and There is an l shaped brash fitting in the head cover. I am thinking it is the overheat sensor but it has a vacuum hose hooked to it and it isn't connected to anything. Would someone know what this is and where it hooks up to? Thanks a bunch for any help ya can throw my way!!


This is a 6 cylinder tower of power engine..

Well I changed the impeller put it back together. Just a question on when the water is suppose to start squirting out the upper pee hole. Does the engine have to start and run for it to get to that point. I turn it over maybe thats not enough speed. I have the ears on the lower unit with water on. It also appears I get to take all the carbs off and clean them. I have nice blue spark at the plugs. Gave a lil shot of starter fluid and that cylinder almost started. I didnt do much I hear starter fluid if rough on them. Sooooooooo I guess its carb time. Bulb pumps up hard.. Thanks.

 

[Rick Stevens]

changed the impeller and put the ears on ,water on and cranked. Wouldn't start. Does the engine need to be running to get water to come out of the upper pee hole?? and I guess I get to clean/rebuild the carbs. Wouldn't start. Put a little staring fluid in one cylinder and it tried to start.

 

[merc850]

Yes it usually takes a couple of hundred rpms to get the water to flow. Try trimming the engine up then pump the primer bulb, gas should run out of the carbs. Tip it back down and start it. Are you using the fast idle and choke?

 

[Rick Stevens]

Yes it usually takes a couple of hundred rpms to get the water to flow. Try trimming the engine up then pump the primer bulb, gas should run out of the carbs. Tip it back down and start it. Are you using the fast idle and choke?

I got it running and de carbed the pistons and rings..I ran a gallon through it with a can of seafoam. Man I smoked out the neighborhood. And these 2 strokes are thirsty things. Didn't take long to run a gallon through it. This is my first outboard I ever fired up from sitting for 6 years on the boat..

 

[Rick Stevens]

And I noticed it wasn't charging the battery It was loosing volts. Engine runs fine. I read at the battery it should read 13-14 volts while running. Something else to figure out.