Adding Water Pressure Gauge...

[Jimmy Jam]

Just wondering how hard it is to add a water pressure gauge as far as actual connections go?

Is the hookup connection...the water line itself? Obviously there's an electrical hookup if the gauge is backlit, but if it doesn't?

Saw a TELEFLEX at the Marine Store I'm kinda interested in.

Never done one.

 

[Silvertip]

Re: Adding Water Pressure Gauge...

Instructions come with the gauge. There is a backlight so only two wires are involved. +12V with the lights on (tap into any of the other gauge lights) and ground (tap into any of the other gauge light grounds). A small diameter hose runs from the engine to the back of the gauge. The installation at the engine looks like this: (Mercury shown but same on virtually any engine). The Larger tube is the tell tale. The small one is the pressure gauge feed.

 

[Jimmy Jam]

Re: Adding Water Pressure Gauge...

Thanks a bunch! About what is the average pressure should I be seeing?

 

[Silvertip]

Re: Adding Water Pressure Gauge...

Since you haven't told us what engine you have, what year, what HP, I can only guess since no two engines (even identical) will register exactly the same water pressure. The idea is to install a new water pump impeller at the time you install the gauge. You then note idle and wide open throttle water pressure readings. Any deviation from those numbers later is an indication you have a water pump issue. The gauge is also helpful if you intend to experiment with engine mounting height via a jack plate or simply raising the engine on its bolts to optimize performance. You can raise the engine so high that the water inlet ports are so high they can't suck water. The gauge also lets you know if you if weeds have plugged up the intake. Lastly, just because you have good water pressure does not mean the engine is cooling properly. It only monitors water pressure. So ideally one could have both water pressure and temperature gauges. My Merc runs about 5 PSI at idle and 15 - 17 PSI wide open. Yours will likely be somewhere in that range but it depends on what engine you have. Unless you change the impeller, you have no idea what's "normal" for your engine.

 

[Jimmy Jam]

Re: Adding Water Pressure Gauge...

Thanks Silvertip. My motor is a '76 E-Rude 85HP. I don't know the full history of the motor, but I do know that before I got her, she had a thorough checkup/tune up...plugs, wires, coils?, powerpack, fluids, etc., verified with receipts. I didn't see impeller on the list though.

I'll have her looked at again this fall, and a new impeller installed as well. Then I'll add my tell-tale as well as pressure gauge.

Once again, Thanks!