V-6 Johnson Evinrude Trapped Air Pocket

[EGallant]

Anyone know of a modification for these motors to prevent a air pocket in top of water jacket between cylinder banks known to cause an overheat condition in top cylinders???

 

[rodbolt]

Re: V-6 Johnson Evinrude Trapped Air Pocket

what year and HP are we dealing with ?

 

[EGallant]

Re: V-6 Johnson Evinrude Trapped Air Pocket

200 HP 1996 J 200 TXEDR

 

[rodbolt]

Re: V-6 Johnson Evinrude Trapped Air Pocket

never had the problem on a OMC V motor but the odd engine that had the air lock problems we ventedwith a drill, a tap and a nipple with a bit of tubing. I would suspect a pressure control or T-stat issue. especially if the stats are missing or stuck open. they are part of the pressure control system.

 

[seahorse5]

Re: V-6 Johnson Evinrude Trapped Air Pocket

You might be refering to the plastic "blow off" valve on the '93 and later "closed deck" cylinder blocks on the 200-225's. Until they added air bleed grooves on the valve in 1997, sometimes the water passage would airlock if the motor was started at idle and not accelerated. The service fix was to drill a 1/8" hole in the nose of the plastic valve to bleed off the air while the cavity filled with water or replace it with a '97 or later part.

 

[EGallant]

Re: V-6 Johnson Evinrude Trapped Air Pocket

You guys are unbelievably motor wise. My engine is a 1996 200HP and is hot on the top at start-up. T-stats are new and pressure control seems ok. What 1997 part are you refering to? Or what plactic valve to drill and tap, 48 years as Tool& Die man, can drill and tap in my sleep. Thanks Again ED

 

[seahorse5]

Re: V-6 Johnson Evinrude Trapped Air Pocket

Look for the round "cap" with 2 hoses coming off it on the back side of the engine block. Remove the 2 screws and carefully remove the spring, rubber seal, and cone shaped plastic valve. <br /><br />Make sure there is no buildup inside the hole where the water comes out of the block. Some earlier engines had casting "flash" restricting the flow of water.<br /><br />Drill the air relief hole, 1/16" to 1/8", in the nose of the "cone valve".