What is a tell tail?

[ztim]

I thought the water coming out of the engine when it was running was called a tell tale. Then I hear someone saying to install a tell tale on the engine. I'm a little mixed up here. How can you install something on a motor when the motor should have one in the first place? Don't laugh too hard. I really don't know.

 

[JB]

Re: What is a tell tail?

Not all engines had a tell tale, Tim.

 

[Frank Acampora]

Re: What is a tell tail?

The tell tale was a small stream of water squirting out the engine usually at a downward angle (pisser)--most notably on Mercs. It gave the operator a visual indication that water was being pumped through the engine.

Chrysler and early Force engines never had one. The only water that exited the engine above the water line was a bit that came out the idle relief vents in the back of the engine. Thus: some guys that don't trust anything except their eyes want to install a pisser or tell tale.

In reality, unless you look back at it constantly (safety hazard) then the engine can still stop pumping water due to various reasons, you will not notice it in time, and the engine will still overheat. And, with a marginal pump impeller, water will still exit the pisser even when not enough volume is being pumped to adequately cool the engine. Thus: in my opinion, if you want a visual indicator, it is much better to install a pressure gauge in the dashboard.

 

[ztim]

Re: What is a tell tail?

Then to install one you just drill a hole?

 

[DJ]

Re: What is a tell tail?

What year/HP is your Force? It may have one that is clogged.

It's not as simple as drilling a hole. You have to know where to drill it. Then tap it and insert a fitting.

Tell us what you have and Frank will tell you if it's possible.

 

[ztim]

Re: What is a tell tail?

Thanks, but I don't need one. I am kind of new to this and am not up to par on what everyone means sometimes. I guess I need an outboard dictionary of terms.

 

[gjm]

Re: What is a tell tail?

ztim On the top of my 85 force, above the spark plugs there is a plug screwed into the top of the housing. This is where people remove the plug and add a threaded x compession fitting. They then run a copper or other material line down the inside, under the cowling, to a previous drilled hole. The line is then exited out the hole and pointed in a direction of their choosing, for best viewing at their vantage point. The water stream is visual proof that the water pump is working. On your 6hp, you are so close I don't think one would be benifical. There is a larger thread on this subject in the last month or too. You can find it by typing in telltale in the search area.

 

[azlakes]

Re: What is a tell tail?

And, with a marginal pump impeller, water will still exit the pisser even when not enough volume is being pumped to adequately cool the engine. Thus: in my opinion, if you want a visual indicator, it is much better to install a pressure gauge in the dashboard.

Interesting comment. Expanding on this further for options to tell tails sake. Do water pressure gauges have a red zone or do you calculate case by case basis(engine hp). Is an engine temp gauge for outboards an option or distance from outboard to dash prohibative?

 

[Frank Acampora]

Re: What is a tell tail?

As I said in a PM: I have never used a water pressure gauge so I don't know what normal pressure would be.

Water temp gauges on the other hand use a spring loaded variable resistance sender and should read somewhere around 160 degrees. As it heats up the spring expands and forces resistance material closer together. Resistance becomes less, more voltage flows and the gauge reads higher. They screw right into the plug hole on top of 3 and 4 cylinder engines. Only a single wire is necessary. A good pressure gauge will use the same system instead of running a pressure tube up to the gauge. Slightly less accurate but MUCH simpler to install.

I have seen senders on two Evinrudes which were held by a bent piece of stainless bolted under a head bolt and held against a bared spot on the head. They worked well in shakedown but were a little slower to respond while engines were warming up because of less contact area with water (or in this case the head metal at the same temp as the cooling water). So, it is not absolutely necessary to have them mounted in a tapped hole.

 

[ztim]

Re: What is a tell tail?

Well like I said, my motor has one. I was just wondering what one was. Thanks gjm. I'll check out the pics in search.