i need a good mercury guy to answer this one

[curtis_s]

I just replaced the impeller on my 1965 merc200 20HP i am running into an issue... or maybe not. I replaced the impeller as it was totally and completey shot new impeller is in and i think there are no issues.... But i have no water coming out of my exhaust just below the power head. i know this is an exhaust prop engine but i am not sure.... should i have water coming out of the upper exhaust how much... if i blow into the exhaust port it comes out the prop.... if i blow into the fresh water rinse port it comes out the uupper exhaust and the prop... any help would be much appreciated.. thanks in advance

 

[curtis_s]

Re: i need a good mercury guy to answer this one

just found out from the post titled SWITCHBOX by bkusa_2 that I should not be running this OB in a drum or barrel. Is there another accepted method of testing this outboard without having to buy a boat to strap it to? Please help, I know very little about mercury's.

 

[Bear]

Re: i need a good mercury guy to answer this one

As far as I know (and I'm not a good mercury guy) the cooling water goes thru the prop only. The tell tale is for you to know the water is circulating. <br />The upper exhaust holes is for better idle as the water pressure at the prop will make it harder to get the exhaust fumes out that way. At idle that is. <br /><br />I just saw this:<br />"Also...any thru prop exhaust engine should not be run in a barrel as the exhaust can block the water from comming though the intake and damage your impeller."<br />In that case we can't let our Merc's idle on the boat either What is the difference, on the boat or in a barrel?<br /><br />I do know you must have the water level in the barrel above the impeller, not just above the water intake.<br /><br />Some old JonnyRudes have water spray coming out from the exhaust holes (like my '66 Johnson) but it doesn't have a tell-tale.<br /><br />I'm not sure this will answer your question Curtis. If I'm wrong we will know soon and I will edit this out.

 

[profish00]

Re: i need a good mercury guy to answer this one

check the popet valve it may be cloged on my 150 1993 the popet valve feeds the sprayer to the exhaust port. on the lower starbord side of the block.<br /><br />Heck i dont kno im a merc owner....

 

[curtis_s]

Re: i need a good mercury guy to answer this one

thanks, ill try putting more water in the barrel (although it makes me feel like an idiot) to make sure the water level is above that of the impeller. As far as the poppet valve, im not sure my 1965 20hp has that, though i will look for it.<br /><br />another question, if i pull the fresh water flush plug next to the upper exhaust, should anything happen? What exactly is it for? Cause i dont know, and it bugs me that i dont. please help me for i will soon jump!<br /><br />p.s. i didnt mean to bump my post up again, sorry

 

[The Marine Doctor]

Re: i need a good mercury guy to answer this one

The reason you should not run an engine in a barrel is that the exhaust will hit the back of the barrel and billow around to the water intake. I have had many customers that have burnt out their pumps by doing this.<br /><br />In the lake...the exhaust is sent backward to the rear of the engine with no obstruction...it is then allowed to rise to the surface away from the water intake.<br /><br />TMD

 

[alcan]

Re: i need a good mercury guy to answer this one

This problem the good Doctor refers to is possible with all outboards. How ever this doesn't mean you shouldn't or can't run your motor in a barrel or tank. This just means you need to be aware of this and if it is a problem for you, you need to do things different. First of all at idle most of the exhaust goes out the exhaust relief ports above the water line. If you have a larger motor and a smaller tank you may want to add flush muffs as well to prevent this.