Water pressure hose

[jerseyjimk]

I have a 2011 Yamaha 115XA ,how do you eliminate the water pressure hose from the motor, new to me motor and my boat doesn’t have a water pressure gauge.

[jerseyjimk]

Can I just plug it

[boscoe99]

I suspect that you have a four stroke F115XA. Yamaha stopped selling two strokes several years before 2011.

Normally the hose is not eliminated. It is usually plugged and then left loose within the engine pan if it not going to be used.. The next owner may want to use it. I am surprised that it does not already have a plug in it.

[fairdeal]

There's a number of ways to accomplish the 'plugging'

The tapped hole in the motor is M14x1.5 -
a very common oil drain plug size used on many 'import' cars;
you should have no trouble finding something at an auto parts store.

[jerseyjimk]

Yes its a F115XA , I bought it used, the previous owner had a gauge. Thank you for your input, I will plug it and leave it lay on the pan

[boscoe99]

Oops. My mistake. Poor reading skills. I was thinking of the lower unit water pressure hose.

In either case there is not a lot of pressure. Plug the hose or as fairdeal notes, remove the fitting from the block and install the over price Yamaha plug. Or an oil pan drain plug.

[jerseyjimk]

Oops. My mistake. Poor reading skills. I was thinking of the lower unit water pressure hose.

In either case there is not a lot of pressure. Plug the hose or as fairdeal notes, remove the fitting from the block and install the over price Yamaha plug. Or an oil pan drain plug.

Your correct, its from the lower , not the engine block

[walleye1]

That is for speed not water pressure.

[fairdeal]

I was thinking of the lower unit water pressure hose...

In either case there is not a lot of pressure.

Perhaps not on a boat powered by a single F115, but..

[boscoe99]

I was in a bass boat once running in the low 70's. I am not getting into a boat that can run 80 MPH.

Do you have data to indicate what pitot tube pressure an F115 powered boat running at wide open throttle can produce?

[fairdeal]

Do you have data to indicate what pitot tube pressure an F115 powered boat running at wide open throttle can produce?

I have not done anything personally - but Google quickly found this from Teleflex:



Standard calibration speedometers should react to the following pressures:

5 PSI = 20 MPH
11 PSI = 30 MPH
19 PSI = 40 MPH
30 PSI = 50 MPH.

A standard speedometer using the Mercury/ Mariner speed pickup in the engine foot
will read approximately 10% faster than with a Teleflex pitot mounted to the transom.
Speedometers with the suffix "M" after the Part Number are calibrated for use with in-foot pickups.

5.6 PSI = 20 MPH
12.6 PSI = 30 MPH
22.4 PSI = 40 MPH
35 PSI = 50 MPH.

[jerseyjimk]

Way to much information, but thanks for all your efforts, Jim K

[TownsendsFJR1300]

You would be surprised how much water gets up into that speedometer hose. In my 20'4" boat, it was easily half ways forward (under the deck) to the speedometer.

I plumbed a Schrader valve in the CC and run a small 12 volt air compressor to it after each use. It'll blow out easily 1/2 cup of salt water..

And that's a top speed of approx. 45MPH.