Force 120 milky #3 and 4 cylinders

[JDP3FE]

OK so I've read MOT of the forums on this subject and I've ordered the maintenance manual (hasn't arrived yet). I can do the work not a problem, but I want to make SURE that I am doing the right work first. I checked the head gasket and it looks fine. One of the forums said that the exhaust gasket below the powerhead is at fault, but another said it was the reed valves. How the heck can a reed valve cause this? I am about to pull the power head off the motor and check the exhaust gasket, so someone please tell me first if I am heading in the wrong direction BEFORE I pull it off. Also, anyone have a good point of contact to buy these gaskets with fairly rapid delivery?

 

[roscoe]

Re: Force 120 milky #3 and 4 cylinders

h

 

[roscoe]

Re: Force 120 milky #3 and 4 cylinders

gaskets from mercruiserparts.com or any mercury dealer.<br />sounds like you are headed in the right direction, or it could be the exhaust plate gasket on the side of the motor.<br />Click to see picture. <br /><br />There are 2 of them ( #25) one on each side of part number 26.

 

[JDP3FE]

Re: Force 120 milky #3 and 4 cylinders

Roscoe...thanks a LOT for the info and the picture. I looked all over the place and couldn't find a breakdown/picture of the thing. This is the first time I've done this type of work on an outboard but it seems fairly straightforward....but...how could the problem be in those exhaust plate gaskets? From the picture they appear to just seal around the edges of the exhaust plate and exhaust cover. From the forum discussions I thought they were talking about the gasket under the powerhead. HELP?

 

[eurolarva]

Re: Force 120 milky #3 and 4 cylinders

Or you can go with the mega gasket powerhead kit<br />Part number 18-4312<br /> POWER HEAD GASKETS <br /><br />NAPA might sell this kit call them and give them the part number.

 

[TimeOut]

Re: Force 120 milky #3 and 4 cylinders

Hi, Do check the reed valves as I had the same problem on my 97 120Hp.I have gone through 3 sets of reed valves! What happens the engine is unable to hold pressure and sucks water in from the exhaust port. The engine will idle a little rough but under normal operation it is not noticable.<br />Good Luck<br />Alan

 

[JDP3FE]

Re: Force 120 milky #3 and 4 cylinders

Thanks to all for the info. I removed the exhaust manifold cover and I found a four inch crack in the exhausr plate seperating the water jacket from the exhaust. The new one came in yesterday and I put it on today...SUCCESS!!! Thanks again...JD

 

[roscoe]

Re: Force 120 milky #3 and 4 cylinders

Great !!

 

[IMPATIENT 1]

Re: Force 120 milky #3 and 4 cylinders

having similar issues with my 98 120hp force, i keep getting water on the top plug and its not the headgasket, i pulled off the cover last nite but didn't see any cracks. goin home at lunch to check again.

was up with the exhaust gasket below the powerhead? wouldn't all the cylinders get water if that blew?