Depth Transducer

[George H260]

I will be replacing thedepth transducer on my 336 this spring.I was having eratic depth readings last fall and sent the Raytheon Tridata head back to the mfg for a checkup. They found that the gain was off. Just to be safe I ordered a replacement transducer. The cost was $90.00 which I consider to be a bargin. If I put the boat back in the water and the transduced was bad then I would have to haul the boat again. This most likely would eat up the the cost the transducer. So I went fot it.Do you know what hunter used to seal the transducer head? 3M 5200? Will I remove some of the fiberglass when the head comes out?What would be a good material to seal the new one 5200?There also is a marine plywood block holding the transducer locking nut. I think this is just to make up the gap on the transducer threads. Is this necessary if the new one doesnt have the same gap?Any comments would help.

 

[Doug B]

Answers

First. The plywood comes most likely as a recomendation from the transducer company. They recommend rubber, plastic (and wood if needed...but I dont like becuase exposure to water will degrade) as a material to be used on bilge side of transducer. This is actually to take up the slack for any inconsistancies in glass lay and still allow the external flange to lay flat to the hull. 2nd: 5200, 5200, 5200. Yes, Hunter does use it and if needed us a heat gun to soften before removing old transd. Remember to not overheat the gelcoat! Cold 5200 is a bitch to work with. If the new transducer is larger in diameter you will need a hole drill (any hardware store) to install. The literature with your new one will indicate hole size needed. Put 5200 around the flange as the manufacture will indicate and then some on the threads so tightening nut does not back off over time.Read instructions and follow. they will tell you its important to HAND TIGHTEN ONLY. Do not overtighten. Its only natural when it a hole in the bottom of the boat to go to town on it. But this only squeezes out all the 5200 and that is your protection against leaks.Happy sailing

 

[SteveC]

5200???

Are you sure you want to use 5200 for a bedding compound??? I also am in the process of replacing the depth & speedo and have popped out the old transducers. They came out with just a little persuasion so I don't believe they were in with 5200 because as i understand it, I would have had to use a jackhammer to get them out. I have also removed the strut and rebeded it with a polysulfide?? that was also recommended for below the waterline and no problems. If in fact the instrument transducers were not 5200, they have remained sealed for 13 years without leaking..

 

[Mark Johnson]

I WOULD NOT use..

5200 when replacing that transducer. 5200 is great when you do not want things to come apart. Transducers do go bad and need to be replaced. I would use 3M 4200. It is designed to be used on stuff that may need to be disassembled. You want to caulk to prevent leaks, not make it a permanent part of the boat.Mark Johnson

 

[john w.]

depth transducer re-fit

I was having problems with my tri-data two years ago.You can tell if the transducer is functioning by placing your ear tight to the transducer head and listen for a ticking sound.( out of the water ) My problem was cabling damage.I did pull the transducer and re-bedded with 5200.The wood spacer takes up the irregularities in the fiberglass and can be shaped to allow the nut to seat flat and true. This will allow the head to seat evenly. Do not over tighten the nut.

 

[George H260]

Thanks

I read 4200 was almost as strong as 5200 but would allow easier removal at a later date.I will give it a try.Thanks