Third powerhead in three years 70 hp Johnson

[Santiago]

My 1975 70 hp Seahorse has had three remanufactured powerheads installed on warranty in three years because of water in the cylinders. The shop says this is just bad luck with the rebuild job, but I wonder if there might be something wrong with the surfaces on top of the lower unit that match up to the bottom of the powerhead. The shop says no, they would be able to see any problems there. Is this "bad luck" common or, if not, do you have any suggestions? I'm kind of stuck with these folks because of the warranty.

 

[DJ]

Re: Third powerhead in three years 70 hp Johnson

Sounds like some bad luck. There aren't that many places where water can get in.<br /><br />Has the installer retourqued the cylinder head after each break in?

 

[Dhadley]

Re: Third powerhead in three years 70 hp Johnson

Where is the water getting in? Is it from an internal crack each time or is it from water injestion?<br /><br />If the water is in the top and bottom (bearings and / or cylinders) and is cleaner as it gets toward the middle, thats water injestion. Probably due to set up. <br /><br />Let us know!

 

[Santiago]

Re: Third powerhead in three years 70 hp Johnson

To djohns: They say they retorqued the head bolts on each 20 hour check-up, but who knows?<br /><br />To Dhadley: In this particular instance the shop guys say the water is coming in the exhaust port but, on the first two replacements, they didn't seem to exactly know. The first replacement was done because the engine stopped when it couldn't compress the large volume of water. These last two times the engine seemed to run well but presented a whitish mixture of water and oil clinging to the spark plugs. To answer your question as best I can, the water seemed to be about equal in all three cylinders