Mercury 2.5L 200 rigging questions

[phatdaddy]

not to de-rail, but i never saw the use of a trim gauge on a small boat. just turn around and look at the engine. i use the tach to let me know when i am getting to the sweet spot when running. i understand it on i/o applications. use that hole in the dash for your water pressure gauge, much more critical info, to me.

[jasoncooperpcola]

Phat you got me thinking. I have never had a trim gauge on any boat before. Well, they did have the gauge but never worked. My motor is going on a 30" bracket and the transom will be closed. Should be able to see it. So for gauges i am thinking tach, hours, water pressure, water temp, fuel, and maybe a speedometer. How does the hose on the lower unit work? I can feel the hose by the shift shaft.

[Destroyer]

Originally Posted by jasoncooperpcola

Phat you got me thinking. I have never had a trim gauge on any boat before. Well, they did have the gauge but never worked. My motor is going on a 30" bracket and the transom will be closed. Should be able to see it. So for gauges i am thinking tach, hours, water pressure, water temp, fuel, and maybe a speedometer. How does the hose on the lower unit work? I can feel the hose by the shift shaft.

It's a pitot hose. A pitot tube is a pressure measurement instrument used to measure fluid flow velocity. It connects to the back of your speedo and as your boat moves thru the water the water pressure on the air trapped inside of the hose increases, and as the pressure increases your speedo registers that increase on your speedo dial as your speed.

This is a pic of your trim sender.

[jasoncooperpcola]

Thanks Destroyer. Not sure if i will replace my trim sendor. How accurate is the lower unit pitot tube?

[Destroyer]

Originally Posted by jasoncooperpcola

Thanks Destroyer. Not sure if i will replace my trim sendor. How accurate is the lower unit pitot tube?

LOL Don't know...never had mine connected up to the speedometer. I always use my GPS. I had a similar setup on a few of my old boats, they were aftermarket units...I think they were made by aquameter. Seemed ok at slower speeds, but didn't seem to be all that accurate at high speeds. Still, it was better than nothing.

[jasoncooperpcola]

so i will plan on replacing the tube when i take the lower unit off for a water pump.

[phatdaddy]

speedo tube , to me, is more useless than the trim gauge. takes up a 4.25" hole. most just let them run out of the hole on the midsection and cap. to me the most vital gauges are the volt & water pressure, then tach & hourmeter. speedo, trim & gas are a waste of space.