Airmar P79 issues

[Salish Seaker]

At the end of our last cruising trip a few weeks ago, the depth finder started flashing. After reading threads from this site, I concluded that the Airmar P79 transducer needed to be refilled with anti-freeze. I twisted off the transducer and refilled. However I've had difficulty screwing the transducer back onto the fill cup ever since resulting in unreliable depth readings and flashing numbers. I spent a lot of time trying to seat the TD correctly on the threads, it keeps "popping" up, not seating properly. The threads don't look stripped, it just wont twist back on properly. Has anyone else had this issue?

 

[Scotty Mac]

Check the o’ring and see if seated correctly, you maybe crushing it and not allowing full thread engagement.

 

[Salish Seaker]

Thanks Scotty Mac. I think you're correct, I didn't install the O-Ring properly. Sometimes it's just the simplest things. 😉

Peter

 

[BB marine]

https://www.google.com/url?sa=t&rct=j&q ... g75bhwkOcj

This is the installation manual showing placement of the o-ring. There are no threads. It is a twist lock. Make sure both tabs are in place and not broke off from top section that screws to the transducer. One tab and o-ring was missing when we took delivery of the boat. I installed the o-ring (not knowing a tab was missing) sounder now worked, but the top section would not stay locked down properly. I then noticed a tab ( described as Boss in manual) was missing. Replacing the top section and o-ring and this fixed the problem fixed the problem.

 

[Salish Seaker]

Thanks Brian. Sorry I didn't see your response earlier. I'll check my transducer out the next time I'm at the boat. That's a much better diagram than the one I was using. I don't remember seeing those tabs (bosses). And I know I didn't put the o-ring back correctly. Hopefully that will correct the problem.

Peter

 

[trailertrawlerkismet]

The depth sounders are only good for so many feet of measurement, when it starts to read something past your set depth the unit will start to flash, as you explained. You can set the depth to read deeper but you then start to loose accuracy and once the unit reads past that newly set depth it can start to flash again. I don’t think you can eliminate the flashing completely, unless you stay in shallow water all of the time.

Jim F

 

[fishheadbarandgrill]

The depth sounders are only good for so many feet of measurement, when it starts to read something past your set depth the unit will start to flash, as you explained. You can set the depth to read deeper but you then start to loose accuracy and once the unit reads past that newly set depth it can start to flash again. I don’t think you can eliminate the flashing completely, unless you stay in shallow water all of the time.

Jim F

My transducer loses track at 31 feet and only reaquires the bottom when I enter water that is shallower than 31 feet. Where do I set the depth? I thought they all read to their max depth which is factory set based on the technology of the transducer.

 

[bob daily]

Bob
Something is wrong with or set up wrong on your unit!
Don't know what GPS system you have, but get into system setup for depth/transducer and most have auto for depth setting. Your transducer should read down to 800-1200 ft depending on frequency selected. Lots of Y-tube videos that will explain how to. A good unit should not have a problem or lose depth (flashing) until max depth is passed at which time the signal is too week for unit to read.
Good luck on the fix. Bob

 

[Cutwater28GG]

1. check fluid
2. check your sonar settings. gain, noise reduction etc. set to defaults as the starting point.

 

[fishheadbarandgrill]

I got into my chertplotter and the sonar ax depth was set at 30’... go figure. Si set it to auto and will test tomorrow

 

[King Fischer]

I have a P79 on order from Defender. We have an older sounder from Ray Marine. It was hard getting the right one for the older sounder. Airmar found one for me from Defender. Who had ever installed ours had epoxied the transducer right to the hull without the cup for the glycol fill. I think after time it quite because of over heating. Our new one will be liquid filled.

Les

 

[Cutwater28GG]

the epoxied on transducers tend to dry out and crack. I reinstalled mine with the glycol cup. much better performance. now I can hear the transducer clicking from the helm the contact is so good!