tips on removing/replacing transducers

[witzgall]

Hi all;

The Depth and speed units on our boat are the original B&G Hunter analog displays from 1985. I picked up a Simrad IS 12 Combi display with transducers for under $100.00 so I want to replace and install the "New"ones.

The B&G tansducers are both removable. The speed housing is plastic, and the depth is a flush (No flange) metal housing.

I have never installed, nor removed transducers. I imagine that I would start the removal process by pounding out the old ones from inside, with perhaps a bit of heat gun to help things along? Then finish the removal fro mthe outside once ther is a bit to grip?

Could I bed the new transducers in 3M 4000 sealant?

Any tips on the whole process?

Thanks,
Chris

[witzgall]

44 views and not one comment? Man, I thought everyone here had an opinion on all subjects!

Chris

[Charlie]

I have never done that before but am interested in purchasing the B & G equipment from you after you get the Simrad installed.

[limmer]

I had to drill out the old one with a hole saw (which was plastic) and chisle the rest away because it was not going to move. the only issue you will have is if the new transducer is smaller than the new one. to make a new hole larger i made a wood plug to fit tight in the original hole marked the center thus giving me start point for hole saw drill bit to keep it centered.

[Alan Wheeler]

Probably no replies because we need more info.
What is the hull material?? Take it easy if it is GRP.
Are these bedded in with a flexible sealant or epoxied in place. Are the transducers sleeve mounted. Can't find the right word I want, but in other words, are there fittings in the hull and the transducer itself can be removed for cleaning etc?
I have not used 3M 4000, but if it is a Urathane based adhesive sealant, then yes it will be good. I believe many here sing the praises of 5200. It could be the better choice perhaps.

[witzgall]

You ask, I deliver:

Hull is solid GRP. The Transducers are removable, I need to get out the fittings. I have not a clue how they are bedded. I am hoping they are not epoxies in place!!! I don't want to use 5200, as I have heard that it will be very difficult to remove if need be. I guess I want something "good enough" Strong, but not too strong??

Chris

Originally Posted by Alan Wheeler

Probably no replies because we need more info.
What is the hull material?? Take it easy if it is GRP.
Are these bedded in with a flexible sealant or epoxied in place. Are the transducers sleeve mounted. Can't find the right word I want, but in other words, are there fittings in the hull and the transducer itself can be removed for cleaning etc?
I have not used 3M 4000, but if it is a Urathane based adhesive sealant, then yes it will be good. I believe many here sing the praises of 5200. It could be the better choice perhaps.

[witzgall]

I got them out today. The plastic speed transducer came out very easily, it was an unusual multi-part contraption. The depth was not so easy. It was esentially a three inch long threaded bronze tube, that was fiberglassed in up to the top. Imagine something that looks like a mini volcano from the inside. I had to drill, saw and grind the volcano down, while I used a 2" hole saw from below. In the end it popped out easily, but not without several housrs of effort.

Chris

[David M]

...sounds like child birth!

[Pblais]

While 3M 5200 is often the curse from a previous owner it does have purposes for proper use as well. A below the water line through hull would be one of those few times.

Yes, it was quite a nasty job to remove the fitting. I would argue that it should be. It's not a common thing and the alternative could be a major disaster. I would assume you want the new one to come out with extreme difficulty too?