What’s with dummy lights?

[rslifkin]

Originally Posted by a64pilot

So why do boats have tachometers? Those of you that don’t want gauges, why do you want a tach?

As much as it's not ideal, a tach is the best way we've got on most boats to set an engine to an approximate target power level.

[Montanan]

Say what! You mean your boat doesn't come with a universal Check Engine Soon light?

I prefer to install audio alarms so as to be made aware if sensors indicate that things are going off kilter and then to be able to go view the gauges to determine which issue is raising an alarm. As to oil pressure, I often see a wide variance in pressures across similar engines, not sure if it is the gauges that are reading incorrectly or just large variances in actual pressures. I get concerned when I see the pressure drop below what is customary for the specific engine, say, e.g., shifting from 25 down to 10 psi.

[Cadence]

Originally Posted by NorthernMac

I’ve seen quite a few posts about people saying once the low oil pressure light came on.

Why don’t more people install and insist on having a oil pressure indicator?

I mean for me I feel odd not having CHT/EGT for each cylinder, but I get it, it’s a boat, still not having oil pressure to match against RPM and temp, plus the lack of folks who cut their oil filters and inspect the eminent on oil changes..

I’m all for adventurous, but dang

A sending unit for a gauge can give You ulcers when it goes erratic. I'd rather have one than a light.

[Thumbs Up]

The idiot light gives you a way better chance of shutting down in time if there is a sudden problem. I would choose a light over an oil pressure gauge. A temp gauge is essential but would be nice to have the light as well As for the alarm, not loud enough to hear over the roar of both engines on Thumbs Up! I also have overheat alarms on the exhaust but are nowhere near loud enough.

[LouK]

The answer is: when boats start to fall out of the sky, we’ll all have CHT/EGT gages. If you’re used to scanning in an airplane then scanning in a boat isn’t that much different.

[Thumbs Up]

Might as well install some. More bells and whistles!

[keyway]

Gauges. We don’t need no stinking Gauges!

[Crusty Joker]

a64pilot always has great comments...
Idiot lights are for... wait. Idiots and those who are distracted by inattention, too much attention, or by hostile current events. Boats are all operated by people who occasionally sound brave at the bar in the yacht club, but I prefer to sail with someone who has known FEAR and admits to ignorance.
I used to help teach a class with a real professional engineer and master mechanic. Class title was "Care and Feeding of small diesel engines for marine use". We also had one for the building engineers with a similar title. The object was to teach maintenance and operation as well as the basic theory of the diesel engine. It was pretty fun to hear the stories of those who had problems thinking operation of a vessel at sea was as simple as the key ready Mercedes sedan being used to go to the market. Very few gasoline engines will take the continuous operation with reliability that can be obtained from a diesel. I once built a Healy and drove from Los Angeles to New Orleans in about 26 hours. Mostly my foot was pushing a dent through the floor. My eyes were in constant scan across the instruments and looking for those who are most absent today - law enforcement. You want to be able to exceed normal limits you must be built to the task and prepared ahead of time. Rehearsed.
Eyes ears and nose. The feel of the vessel through feet and hands. Experience and education. The KSA's. Know your vessel and your own limitations.

[valhalla360]

Originally Posted by a64pilot

So why do boats have tachometers? Those of you that don’t want gauges, why do you want a tach?

On twin engine boats, it's really nice to keep the engines sync'd.

On single engine boats...not much point.

We've had tachs on our twin engine boat and not on our single engine boats.

I like gauges but I don't know that I would pay a lot more to get a gauge package if buying a boat.

PS: I believe Icon comes from Eastern Orthodox tradition. There is a very specific way of "writing" them, so in principal the same Icon should always look the same...hence just a glance and you recognize them. In the same way a computer icon should be simple and consistent and recognized with just a glance.

[Phyrcooler]

Originally Posted by Thumbs Up

The idiot light gives you a way better chance of shutting down in time if there is a sudden problem. I would choose a light over an oil pressure gauge. A temp gauge is essential but would be nice to have the light as well As for the alarm, not loud enough to hear over the roar of both engines on Thumbs Up! I also have overheat alarms on the exhaust but are nowhere near loud enough.

Agree! - and just to clarify - I am a strong advocate for having gauges, however, that is always IN ADDITION to lights/alarms for low Oil pressure/High temp. I am also a pilot, and while i understand and would conduct near constant instrument scans in an airplane - while in a boat, we’re not strapped into a seat right in front of the gauges. There are multiple reasons we move about the boat, especially while Otto’s helming, to say nothing of going below to grab a drink or use the head. Returning to the helm after several minutes of a problem could be costly.

The other problem with these warning lights on boats (I’ve never called them “idiot lights”) is frequently the light is located somewhere below my knees - like right next to my ankle! Great for viewing on a sunny day!

[a64pilot]

Don’t most twins have auto sync now? If not I always sync’ d by ear. Your ear is more accurate than a tach for synchronizing.
Point is a tach is no more essential than a water temp gauge or oil pressure gauge, you can’t over rev the engine, there are no gears to shift, what’s the need for a tachometer?
Actually they are about the most useless gauges you could have, because they monitor something that really doesn’t need monitoring, exception I guess being if you have a cone clutch transmission, yet no one it seems would dare sell a boat without a tachometer.

I think it’s like the Miata’s oil pressure gauge, it’s a sorts car and all sports cars must have an oil pressure gauge, but most Miata buyers aren’t really “Sports car” types so you give them something that they think is an oil pressure gauge, but won’t worry them like a real oil pressure gauge will.
Same car has a water temp gauge, and it sort of works, but has what Piper aircraft calls a “snap” function, meaning when you get close to the expected reading, it will go there and hold that expected reading unless you go way above it, then it becomes live again.
So once you get close to warmed up the water temp gauge never moves, but of course the water temp does.

They went to a lot of trouble to placate the uninformed, and of course tick off the informed, but that’s to be expected.

[valhalla360]

Originally Posted by a64pilot

Don’t most twins have auto sync now? If not I always sync’ d by ear. Your ear is more accurate than a tach for synchronizing.

On new boats they auto sync but not on a lot of older boats. I'm sure if you are buying a new $400k boat and you tell them you want certain gauges, they will put them in.

Your a better man than I sync'ing by ear on a pair of roaring V8s (I suspect a couple of small 1 lung diesels put-putting along would be even harder).

I could get close but if I centered the wheel and let go based on sound (calm day, no wind or current), it would drift off to one side or the other. If I matched the tachs, it would stay straighter, which I assume means the thrust is pretty much equalized.

[Crusty Joker]

I use a digital or hand held mechanical tach when I set the output power and max RPM on an engine using the fuel pump... I enjoy having lots of instruments to observe details about engine function over time. Some fuel metering devices I have come in contact with are more than $50,000, a tenth of the value of the engine and its purpose at installation. That said, most people do not require much in the way of instruments. Temperature gauge is preferred over idiot light, alarm is a good idea as an extra. Oil pressure gauge is preferred over idiot light, but low oil pressure alarm is a good idea as well. One thing I can add here is that the idiot operating the vessel should be at the helm when underway, in command, not chasing an imitation admiral below deck... Several stories have been told about captains running into the local islands while doing a refill on the coffee cup. The most important item on the boat skippers list should be his head. The one on his shoulders. Stay sober until docked or moored and all are safe. Peace Prevails by Intention.

[rslifkin]

I sync my twins by ear, but it's much easier if you can get them close with the tachs first. If you know you're within 50 rpm or so, it's usually just a small tweak or 2 to get them synced.

[NorthernMac]

I was debating installing a master caution on the boat, but I cant figure out a easy way to do it and don’t want to get too crazy on my little 2 cylinder diesel lol

That said it failing at the wrong time could kill me just as dead as the pratt shitting the bed