Johnson very high water pressure

[flatsman]

I have an engine 1996 115 ocean runner that ran at 25 to 30 psi water pressure. Water was leaking in to the port lower cylinder but very little. The head was removed and a new " o " ring was fitted and the head reinstalled. The water pressure went higher to around 4o to 50 psi at 5200 rpm on the open water in a test run . Later it ran about 1.5 miles at around 3800 to 4100 rpm and about one quarter of mile at 5200 rpm. Shut the engine down for about 30 minutes to fish. Started it up again and it went to making a knoting noise , shut it back down again. When the head on the port side was removed , we found steel fragment in the cylinder . What could have caused this or are their any ideas from you folks?

 

[ob]

Re: Johnson very high water pressure

Have you inspected the T/stats and relief springs?Those pumps are positive displacement and will pressure up until they or something else gives.Did the engine overheat at any time?If guage is accurate ,you have a restriction somewhere in the engines water passages.I'll take a guess and say that you have a problem with one or more of your water deflectors.

 

[flatsman]

Re: Johnson very high water pressure

no, engine over-heat problem that day but did get hot alarm in the lake on the third lap but just for a 10 seconds or so ran fine at 34oo to 3800 rpm. pulled engine cover on the problem day and it was not real hot nor did it ever over heat on the trip out of the river. alarms system check is fine .

 

[Solittle]

Re: Johnson very high water pressure

My theory - Too high water pressure blew the head gasket whick let water into the cylinder while running at high rpm which resulted in detonation in the cylinder which can chew up a piston/rings.<br /><br />Mine went like that sorta - the water in mine got in through the air intake to the carbs at 4400 rpm but the result was the same - - and $4k for a rebuilt powerhead.

 

[rodbolt]

Re: Johnson very high water pressure

hello<br /> I am guessing by your O-ring comment you have a 60 degree motor. this block is of the closed deck design. hence no head gaskets. my guees is the pressure reife valves stuck in the seats. they come as a kit now. they are located behind the 13/16 hex plug at the top of each head. I suspect either excess silicone or another obstruction in the water discharge from the power head. I have seen the points at which the hot water gets dumped from the power head clog though usually some overheating is observed. try to test the springs, diaphram and t stats. good luck sounds painful. dont run it further until a complete teardown and inspection. also was there any other work done? there are several pump kits availible for v4-v6 but only one works properly yet all fit.

 

[flatsman]

Re: Johnson very high water pressure

The t-stats were pulled after the lake run and checked by the marine mechanic. The head plate or head was removed and replaced by a marine mechanic , although there seemed to be an extra amount of some blue colored gasket or silicone from a tube. The water pressure has been high on this motor since it was installed ,20 to 30 psi but got higher after the "o" ring installation on the port head/cylinders. Doing some real searching on this one aren't I. Darn fishing is getting expensive.

 

[rodbolt]

Re: Johnson very high water pressure

hello again. the service manual says to use silicone sealant when reinstalling the head. I personally hate the stuff. it mushes out everywhere and you cannot help where it mushes into. I would definatly look at all the water discharge ports in the power head adapter area while the power head is off. that engine has a closed deck so it is hard to see inside the block. time for a long thin wire a good light and a lot of patience. good luck and keep us posted

 

[flatsman]

Re: Johnson very high water pressure

Ok here I am again with another question. Why was it the lower port cylinder that gave the problem, rather than the top and bottom port cylinders.

 

[flatsman]

Re: Johnson very high water pressure

This story gets worse !!!! I started tearing the engine down today and found a extra hole in the crank cover on the lower port cylinder. This ain't good. Now my question is this , will a crank cover from another engine fit on to the block ? I have heard that they are a mated system but also have heard that some folks have made one engine out of two with now problems. What are the experts opinon on this ?? or will i be able to weld this hole up ??

 

[fgwebb]

Re: Johnson very high water pressure

I have a 1996 Evinrude 115 that also gets water in the bottom (#4) cylinder. My water pressure is normally 25-30 at 5300 RPM. Did you ever find out how the water was getting into that cylinder?<br /><br />thanks