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2006 BF115 - water in oil

jglisso000

New member
I have a 2006 Honda 115 with only 45hrs - prior owner rarely used the boat and never flushed engine it seems. First time using the boat it ran hot and there was a bunch of water in the oil. Compression numbers are good though (180-185 over all 4 cylinders) and it passed a leak down test. We have pulled the head and the head looks good and the gasket did not appear to be blown. Any tips on what to do next?

Jeremiah
Jax, FL
 
Me? I would pull the head and go over the mating surfaces very carefully, as well as the gasket itself, looking for evidence regarding the source of your evil.

An engine that's been overheated, for any reason, can destroy a head gasket.

I'd also be looking at the pump and thermostat to see if one of those caused the overheating - which happens often as not.
 
A few things that you should check and do first if you think that you have a fuel delivery issue:

Make sure your primer bulb is pointing slightly UP at the outlet end. This ensures that the check valve doesn't drain back toward the tank.

Closely examine the quick disconnect at the engine. Vibration causes the pin and check valve ends to wear down. This can restrict the flow of gas. Make sure it latches securely too because if it's loose or off center the pin won't open the valve all the way.

Empty the fuel chamber ....that's the black rubber cylinder attached to the engine oil dipstick tube. The fuel chamber tends to act as a water trap over time and this will interrupt fuel getting to your carb. Empty it out st least once a season to prevent hard starting and poor running.

Lastly, the fuel pressure specification is: 19.3 kPa (2.8 psi) @ idle. Or, as I like to say when you don't have a proper low pressure gauge.....a solid GERBURBBLE when you spin the engine.

Good luck.
 
Sorry,
The above response was meant to address a different poster's issue. I don't know how I got this posted over here.
Please excuse!
 
Not sure on this one but many outboards have the water from the pump travel up through the oil sump gasket to reach the block. Even then it's very rare that this "interface" fails. Especially on one with such low hours.

Another thing I've run into over the years on various engines are porous castings. Never seen that with Honda and, since the cooling systems on outboards aren't pressurized, I'm not sure it would cause the water to enter the oil. Having the head pressure tested is the only way that I know that you can detect that.

Again, pretty unlikely with Honda quality but possibilities to Ponder if you can't find the source.

Good luck.
 
I work on a lot of the older Honda engines that have a pretty "salty" background. If I pull the head and see no major issues, I'll often gamble the price of the gaskets required to change a head gasket and an oil change.

Then, with lower unit removed, I hook a garden hose to the water line above the water pump. You don't even need to start the engine this way. Just let the water run and check the dipstick for water droplets every few minutes or so.

If there is no water in the oil, I'll finish up the project and run it, knowing the block and head are OK.

It's not about engine time. That makes no difference. It's about how the engine was maintained and how long it's been in salt water.
 
Did you check the thermostat and water pump as suggested and what did they look like?

Was the oil and oil filter a fresh change by you or was it of unknown age? How much water was in the oil- what colour was it?
 
If NSDON is thinking built up condensation due to lack of use, that's not a bad thought. An oil and filter change, in the grand scheme of things, is a pretty inexpensive step in trouble shooting if it hasn't been done already. Great thought....

I'm so used to working on the worst case scenario, I may have jumped to a conclusion.

Another thought would be regarding somebody starting a motor and letting it run just a couple of minutes prior to shutting it off. Done often enough, a motor like that may show some water as well...
 
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