replacing temp gauge on Volvo AQ125

[2stroke1971]

The needle on my temp gauge broke, and while I can still read the stub, I want to replace it. Originally it was a US marine gauge in an '85 bayliner. I bought a new old stock volvo penta branded gauge...but it did not come with a sending unit.

I know now that the existing sender adn the new gauge may not be compatable, but I have a question about the connections. My old unit has three connections, and a molded connector unit that only goes on one way.

The new gauge has three posts that are marked as follows: two that are insulated from the case marked "I" and "S", and one of the two uninsulated posts is marked ground. If I were to wire this gauge in, the ground is obvious....does anyone know what the I and the S denote? One of them 12v and one the sensor wire? The sending unit has only one wire by the way.

The only way I would feel good about using this one is if I take the old one out and make sure the boat is running normally, and then swap the new one in and see if it reads the same.....

yeah, yeah, I should just buy a new gauge with a new sensor but Ive got more time than money.

Thanks in advance for any info!

 

[Don S]

Re: replacing temp gauge on Volvo AQ125

Most boat manufacturers use the same sending units that came with the engine, it just makes life simpler for them and people trying to replace the sending unit.

On your gauge, Purple goes to + (I), black goes to - (ground), and sender (S) will be the green wire for Volvo, not sure what Bayliner used, but out of the 3 terminal harness, you have Purple, black, and whatever.

 

[raven1978]

Re: replacing temp gauge on Volvo AQ125

As Don said, Volvo should be green, but on the wiring diagram i have, it seems that Bayliner uses TAN as their Temp sender

 

[2stroke1971]

Re: replacing temp gauge on Volvo AQ125

Thank you gentlemen!
Much appreciated!