fitting transducer

i am just about to fit my new transducer for my furuno and i was wondering what screws i should be using..
it is going to be transom mounted on an aluminium boat....

do i use s/s 316 self tappers? i was under the impression that you need to put sikaflex in between the screws and the ally??


any help would be great as im not overly excited about electrolysis


thanks guys



wangler's picture

Posts: 598

Date Joined: 26/04/08

Just make sure you

Wed, 2012-04-04 09:38

pre-drill the ali for the stainless self tappers, otherwise the heads will snap off, and yes use some sika behind the plate.


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scottnofish's picture

Posts: 1535

Date Joined: 28/08/07

get some

Wed, 2012-04-04 09:40

duralac joint compound ,stops the corrosion between the ali and the stainless screws

strike_zone's picture

Posts: 402

Date Joined: 09/09/10

tef gel

Wed, 2012-04-04 12:34

get some tef gel to put on the screws to help inhibit corrosion duralac is another one but tef gel seems to last a lot longer just remember this stuff only inhibits and will not work forever so you may want to reaply sometime down the track and a bit of sika around the head of the screw and she will be good

sea-kem's picture

Posts: 10404

Date Joined: 30/11/09

Something else you need to

Wed, 2012-04-04 15:05

Something else you need to consider is the thickness of ali you are going through anything 5mm or more you would use fine thread self tappers less you use coarse thread.


Love the West!

Posts: 354

Date Joined: 25/03/09

Big arse ali pop rivets/. We

Wed, 2012-04-04 19:15

Big arse ali pop rivets/. We use them all the time you need lazy tongs to pop them though they are strong as and a sikiflex band in between. No corrosion probs then

Posts: 9358

Date Joined: 21/02/08

Most ali rivets still have

Wed, 2012-04-04 20:42

Most ali rivets still have either steel, or stainless steel heads inside, so you still have corrosion problems.

Just use duralac in any case.


Faulkner Family's picture

Posts: 13551

Date Joined: 11/03/08

 wouldnt you be better off

Wed, 2012-04-04 19:22

 wouldnt you be better off fixing a piece of sealed marine ply to the hull so if you dont get it right the first time your hull wont look like a siev. just a thought.i know on my glass boat there were several holes drilled into the transom over the time and it does look messy with all the patches


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