Pontoon Boat Gauges

[VaGent]

I am rebuilding my pontoo boat & haev no gauges at present for my 1987 Johnson 70 hp 3 cylinder engine. I've been looking at ebay & craigslist & I am lost as to what I actually need as far as name brand & type of gauge. I have no idea what gauges will work/not work with my engine.

I am wanting a a tach (what rpm is needed), a gas gauge, trim, volt & a 35 mph speedometer. I realize everything I mentioned above is pretty much standard except for the tachometer. How many poles is required for my engine & what type of trim gauge will work? Do the gauges have to be strickly for a Johnson outboard or are universal gauges available? Any help would really be appreciated as I am ready to order the gauges & get this pontoon in the water. Thanks

[Silvertip]

All you need to know is that the gauges need to be for an outboard. But here are the essentials:

Tachometer: Universal and is adjustable for number of alternator pulses (yours is 6P). 0-6000 range or 0-7000 range is adequate.
Voltmeter: Not engine-specific. It works with the electrical system not the engine.
Trim: You don't need one if you can see the engine. But if you insist, the engine must have a trim sender and the gauge must be compatible.
Fuel: If you have a built-in tank, you need one. If you have portable tanks you don't. Again, they are universal and not specific to your engine.
Water pressure: Nice to have as it indicates how well or if the water pump is working. Again, it is universal.
Water Temp: Again, nice to have but not essential if your alarm system is working. Essential if it isn't.

Go to "greatlakesskipper.com" for the biggest selection of gauges for cheap. Or right here on iBoats. Most gauges are made by Teleflex or Faria.

[JWRoberts]

Great advice from Silvertip.

I wouldn't install a speedometer because they are never very accurate. If you really must know speed, then get a cheap GPS.

[tashasdaddy]

why do people want guages on boats. once the motor is set up, you do not need a tach. fuel gauges and speedo's are inaccurate, and aggravating. if i have a gauge it is a water pressure sensor, that is all. i/o are different.

[VaGent]

A speedometer is of no real importance to me but I really think a good tach on an old engine & a volt meter is a must have myself. Never know when the alternator (stator) might go out & I want something to see what it going on in advance. A trim gauge would be good to have too as I cannot see my engine unless I get up, crawl over the back bench seat to see where it's at. Same for the gas tank soa gas gauge would be nice to have too. I'm too darn old be climbing over anything these days. The only thing I want to climb is "aboard" my pontoon boat, sit back & relax & enjoy what time I have left.

Thanks for the advice on the gauges.

[Rancherlee]

Like others have said.
Tachometer, NICE to have with a 4 stroke/ DFI, especially when the engine is covered on some pontoons so you know when you have trimmed too much and the engine is starting to cavitate.
Trim gauge IF you can't see the motor and are not too experianced with knowing where your engine is at.

[JWRoberts]

Another alternative to a trim guage is a backup camera. I have one on my boat primarily as a 'rear-view mirror', but it allows me to see my motor position as well.

[TooManyQuestions]

Ok. Stupid question.

Trim gauge.

Im getting a power trim and lift. Motor is out of view from helm.

Should I get. And how do you read it?

[JWRoberts]

Ok. Stupid question.

Trim gauge.

Im getting a power trim and lift. Motor is out of view from helm.

Should I get. And how do you read it?

IMHO, you should get the guage if you can't see your motor.

It is simply a needle to indicate the relative position of the motor. Although the trim of a pontoon boat is not nearly as critical as planeing-hull boats, through experimentation you will learn the best position for various speeds and load conditions. I can often gain a couple of mph with no change in RPM.

I boat in lots of shallow water. When doing so, it is imperitive that I trim my prop as high as possible without ventilating.

[TooManyQuestions]

<<<<I can often gain a couple of mph with no change in RPM.

I boat in lots of shallow water. When doing so, it is imperitive that I trim my prop as high as possible without ventilating.>>>>


ok....Here is the new guy again.

I get what RPMs are and i suspect I want to keep them low. Correct?

This pontoon will also be in shallow water.

Trim as high as possible without "ventilating" means?

thanks

[JWRoberts]

<<<<I can often gain a couple of mph with no change in RPM.

I boat in lots of shallow water. When doing so, it is imperitive that I trim my prop as high as possible without ventilating.>>>>


ok....Here is the new guy again.

I get what RPMs are and i suspect I want to keep them low. Correct?

This pontoon will also be in shallow water.

Trim as high as possible without "ventilating" means?

thanks

You can run at any RPM up to the maximum for your engine which is typically about 5500. Running at lower RPM's will result in more fuel efficiency and a quieter ride. (90% of my cruising is done below 3000 RPM)

Ventilating occurs when the prop is near the top of water and begins to suck air rather than water. You will recognize this condition when the engine RPM increases drastically along with a reduction in speed. With a little experimentation, a trim guage will allow you to trim your motor as high as possible without this condition occuring.

[TooManyQuestions]

Thanks JWR

Memorial Day weekend cant get here soon enough.

While all on this site enjoys the weekend, Thank a vet!