air pressure in pee stream

[ScottinAZ]

Had my '82 evinrude 115 (and the boat it is attached to) on the lake this morning, and was noticing that when the engine is cut off (or more likely stalls, but that is for another post), the pee stream will continue hard for about a second, then there is a burst of air pressure that escapes, and then water will slowly trickle out. The pee stream is attached to the water jacket on the exhaust chest, so could this be a sign of a blown exhaust gasket, a bad head gasket feeding back, or am I just all wet with this?

 

[jbjennings]

Re: air pressure in pee stream

If you have a blown head gasket you should be able to see your spark plugs with milky stuff on them or steam cleaned. If it was blown toward the exhaust side it wouldn't let it pump good when running because it would put back pressure on the system. If your water pump pee stream looks good and hard when the motor is running, I don't think what it does after it's running is a good indicator of a head gasket problem.
JMO---and I have never worked on a 115 so keep that in mind! --- Just trying to help,
JBJ

 

[tashasdaddy]

Re: air pressure in pee stream

i would use an infared thermometer, and check engine temp. tstat could be failing, water boiling, when it shuts down, and pushes out the stream. if really should stop almost immediately when the impeller quits turning.

 

[ScottinAZ]

Re: air pressure in pee stream

both t-stats, bypasses and the water pump are all brand new (replaced just before this trip). Heads are not getting hot, as I can hold a hand on them for a good 8-10 seconds before they are uncomfortable. pee stream temperature is just over the "lake temp" of about 80 degrees so stream temp is about 90-95 or so (lukewarm at best) I also checked the stream to see if it smelled of fuel or exhaust, but no joy, it didnt have an off odor such as unburned fuel or exhaust gas.

 

[tashasdaddy]

Re: air pressure in pee stream

i would just keep an eye on it.

 

[ScottinAZ]

Re: air pressure in pee stream

ok, Sounds good, It just was a bit concerning where it had a definite pressure to it. I will double check the compression on the engine, but last time it was done, it was 110 +/- 5 in all holes.

 

[jbjennings]

Re: air pressure in pee stream

What are those other problems you're having with the motor? It sounds like it's cooling great to me. Maybe some more info. on the other symptoms could help figure out what's going on. I've got a '73 mercury that will pee water for a WHILE after I shut it off.
Later,
JBJ

 

[ScottinAZ]

Re: air pressure in pee stream

new post made about other issues, see "fuel pump?"