Water Pressure Gauge Tubing

[Jason2tpa]

My cousin has sprung a leak in the water pressure gauge tubing. My thought was to cut out the damaged area of tubing (a few inches) and splice together using an adaptor.

Anyone have experience with this? At this time I don't know the brand of gauge he's using, therefore I don't know the inner diameter of tubing. Or do all water pressure gauges utilize the same dimension tubing?

I was thinking of an adaptor like the one pictured below, which connects the LU-MS speedometer tubing. Only difference the adaptor I need is having both ends ribbed.

[panasonic]

My cousin has sprung a leak in the water pressure gauge tubing. My thought was to cut out the damaged area of tubing (a few inches) and splice together using an adaptor.

Anyone have experience with this? At this time I don't know the brand of gauge he's using, therefore I don't know the inner diameter of tubing. Or do all water pressure gauges utilize the same dimension tubing?

I was thinking of an adaptor like the one pictured below, which connects the LU-MS speedometer tubing. Only difference the adaptor I need is having both ends ribbed.

That would work good Jason, as long as the installed tube fits the barbed splice tightly you will be good to go....

[Jason2tpa]

That would work good Jason, as long as the installed tube fits the barbed splice tightly you will be good to go....

Do you know if all/most water pressure gauges use the same ID tubing?

[panasonic]

No I don't know if they are all the same or not. If you are going to cut out the bad section then just take the piece with you to the store and get the right size barbed joiner.

Are you concerned that the gage won't work properly or something if the hole in the splice isn't the same ID as the hose?

[panasonic]

The speedometer works on changes in the air pressure in the hose. The water is forced into the pitot tube on the LU when the boat moves fwd. The water only goes up the tube a short way....not up to the gage. The action of the water pushing up the tube increases the air pressure ahead of it in the tube. This increase in the air pressure pushes on a bellows in the gage making the speedometer needle go up. When you slow down the opposite happens, less fwd motion, less water pressure in the end of the tube, less air pressure at the gage and the needle falls.

I don't know if you knew that or not and where concerned that the splice you want to put in would screw up the speedometer reading correctly.

Same system used on aircraft to measure fwd speed, except no water...just air being forced up the pitot tube.

[Jason2tpa]

Are you concerned that the gage won't work properly or something if the hole in the splice isn't the same ID as the hose?

No. If I know the ID of tubing I can order or find locally the correct size two-way adaptor. Those adaptors like I have pictured here gradually expand, but i recon it's best to have a general idea of the tubing ID. Im guessing in the neighborhood of 1/8". I started this thread hoping someone would know.

[TownsendsFJR1300]

From the factory, there's a hose connector just beyond the engine. That hooks up to the speedometer. You can buy that connector (don't have a part #) at most Yamaha marine parts shops.

As a side note, I "Tee"ed into that hose up under my console for flushing water out of the line/engine.

Yes, it's another slight restriction but checking the Yamaha speedometer against the GPS, even still, it's pretty darn close.. (I can't say it reads lower than the GPS-IE, negligible)

Note, a 5/32" drill bit shank fits just right into the stock Yamaha hose..


http://www.yamahaoutboardparts.com/f...g-th23159.html


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[99yam40]

even a small air leak will allow water to ease up the tube up to the splice(leak) and may cause problems down the road. new tubing should not be very expensive

[Jason2tpa]

The speedometer works on changes in the air pressure in the hose. The water is forced into the pitot tube on the LU when the boat moves fwd. The water only goes up the tube a short way....not up to the gage. The action of the water pushing up the tube increases the air pressure ahead of it in the tube. This increase in the air pressure pushes on a bellows in the gage making the speedometer needle go up. When you slow down the opposite happens, less fwd motion, less water pressure in the end of the tube, less air pressure at the gage and the needle falls.

I don't know if you knew that or not and where concerned that the splice you want to put in would screw up the speedometer reading correctly.

Same system used on aircraft to measure fwd speed, except no water...just air being forced up the pitot tube.

Sorry, I'm a bit unfamiliar with the inner workings of either of these gauges because neither gauge is installed in my boat. I was fishing on my cousins boat last Saturday and noticed a steady stream of water from under console. He says there is a hole in the water pressure gauge tubing.

From reading your words (in bold), sounds like the water pressure gauge and the speedometer gauge function by using 1 pressure tubing from LU to console, then splits into 2 plugging into each gauge.

[Jason2tpa]

Panasonic.....

I don't know if you knew that or not and where concerned that the splice you want to put in would screw up the speedometer reading correctly.

Same system used on aircraft to measure fwd speed, except no water...just air being forced up the pitot tube.

Sorry, I'm a bit unfamiliar with the inner workings of either of these gauges because neither gauge is installed in my boat. I was fishing on my cousins boat last Saturday and noticed a steady stream of water from under console. He says there is a hole in the water pressure gauge tubing.

From reading your words (in bold), sounds like the water pressure gauge and the speedometer gauge function by using 1 pressure tubing from LU to console, then splits into 2 plugging into each gauge.

[Jason2tpa]

even a small air leak will allow water to ease up the tube up to the splice(leak) and may cause problems down the road. new tubing should not be very expensive

Since the location of hole is easily accessible (near console), I thought to just cut it out and splice in adaptor. Zip tie connections. Money isn't an issue for the boat owner. It's the labor involved for a 75 year old salt having to thread the tubing through his boat. Starting to get hot here in FL. I'd hate for him to heat stroke

[panasonic]

I would splice it and see what happens..should be fine.

[TownsendsFJR1300]

Panasonic.....

Sorry, I'm a bit unfamiliar with the inner workings of either of these gauges because neither gauge is installed in my boat. I was fishing on my cousins boat last Saturday and noticed a steady stream of water from under console. He says there is a hole in the water pressure gauge tubing.

From reading your words (in bold), sounds like the water pressure gauge and the speedometer gauge function by using 1 pressure tubing from LU to console, then splits into 2 plugging into each gauge.

The speedometer tubing runs obviously from the LU to the speedo, PERIOD.
And it will only spout water when underway-(outside, water pressure from forward movement)

If he has an ENGINE WATER PRESSURE gauge (with tubing?), that would obviously leak ONLY when the engine is RUNNING..

Two completely different systems..

Should he want a NEW line, simply tape (real good) the new line to the old, and then pull it thru the hull..

The Yamaha line is pretty stout, a simple connector would take care of it..


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[TownsendsFJR1300]

even a small air leak will allow water to ease up the tube up to the splice(leak) and may cause problems down the road. new tubing should not be very expensive

After I "Tee"ed in my fitting for a small air compressor under the console (to clear out that hose and the LU pitot tube, I found about 3/4 cup of salt water laid up inside that tube.

And there were NO leaks, just water pressure and water made it up that far into the hose....

[99yam40]

water can absorb air over time, so I am sure either there was a very small air leak or air was absorbed over time to allow that much water to get up the tubing