1992 mercury xr6 150 overheat @ wot

dave2092

Seaman
Joined
May 9, 2010
Messages
50
Hey guys its been a awhile since I have posted here. Anyway long story short. I finally rebuilt the powerhead its been about about 1.5 years since rebuilt. Hardest part was the needle bearings lol!!! I have been having overheat issues lately @ wot. Replaced impeller in spring ran fine for while. OK then started acting up about week ago. Checked thermostats which were replaced at rebuilt they are fine. Cleaned out pop it valve assembly it's fine. When I changed the impeller put new water pump housing on also and yes new gaskets and yes they were put on in the right order. Tail tail is strong when thermos reach operating temp but here is the kicker when I am @ wot I I understand that the poppet valve on lower starboard side of motor cracks open to give additional cooling. But for some reason @ wot the tail tail starts spitting and stops and steam starts coming out instead of water. Checked all water lines they are clear. I run in river all the time. Any help should I pull bottom end again or you guys have any other idea. Also I can run motor all day at 1/2 or a little more with no issues. I AM STUMPED. Any help..?
 

dave2092

Seaman
Joined
May 9, 2010
Messages
50
Re: 1992 mercury xr6 150 overheat @ wot

Hey guys its been a awhile since I have posted here. Anyway long story short. I finally rebuilt the powerhead its been about about 1.5 years since rebuilt. Hardest part was the needle bearings lol!!! I have been having overheat issues lately @ wot. Replaced impeller in spring ran fine for while. OK then started acting up about week ago. Checked thermostats which were replaced at rebuilt they are fine. Cleaned out pop it valve assembly it's fine. When I changed the impeller put new water pump housing on also and yes new gaskets and yes they were put on in the right order. Tail tail is strong when thermos reach operating temp but here is the kicker when I am @ wot I I understand that the poppet valve on lower starboard side of motor cracks open to give additional cooling. But for some reason @ wot the tail tail starts spitting and stops and steam starts coming out instead of water. Checked all water lines they are clear. I run in river all the time. Any help should I pull bottom end again or you guys have any other idea. Also I can run motor all day at 1/2 or a little more with no issues. I AM STUMPED. Any help..?

Sorry motor is a 1993 s/n od224097
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,146
Re: 1992 mercury xr6 150 overheat @ wot

Sounds like you did everything correctly. Is it possible the water intakes are not pulling water in due to the motor being tilted too high at WOT, or the boat hull obstructing water flow? Are you running a new or different prop?
 

dave2092

Seaman
Joined
May 9, 2010
Messages
50
Re: 1992 mercury xr6 150 overheat @ wot

Never thought of the trim being to high I eyeball when I get up on plane cause my trim gauge is broke :) lost a few ball hats. I always try to keep it level cause I know that if you go to high the motor will over Rev and people think you really getting more speed but you really not. As far as the prop its SS laser 2 don't know the pitch the Guy I bought it off had a brand new bottom end put on and it was installed buy a certified merc mechanic so I am assuming its the right pitch. But may the trim could be the prob. I will pull the bottom end check the impeller to be safe doesn't take long maybe since I run on river I get a lot of dirt in there I know I should flush the motor once in a while but I don't trust muffs. I blew through water lines air is moving free. Also is there a bottom part to water pump assembly I am sure its OK since bottom end is only 2 years old but you never know. Thanks for quick reply. If you have any questions about rebuild on the xr6 let me know it was a adventure like parts and stuff what ever let me know.
 

dave2092

Seaman
Joined
May 9, 2010
Messages
50
Re: 1992 mercury xr6 150 overheat @ wot

I do I have a test run after motor was broken in on YouTube. Under mercury xr6 150 by bassman2092 kind of short and taken video from my smart phone but gives people and idea of the xr6 2 smoker raw power!!
 
Top