270 owners with a transom mount transducer

04FV270riverrat

I'm gonna be installing my transom mount transducer this winter while the boat is out of the water. The hole I need to drill to run the cable through is going to be huge! the cable is small but the plug for the back of the MFD is at least 1/2" to 3/4" in diameter.

You guys with 270's and transom transducer's, where did you drill through for the cable? Pictures are much appreciated!

GMSLITHO

can you just run it above the water line and just under the swim platform 

Willhound

That's kind if how mine is.
By the way, old pic from before I bought the boat. Much cleaner looking now.

04FV270riverrat

GMSLITHO said:

can you just run it above the water line and just under the swim platform 

Yeah I plan to run it straight up and into the engine room above the water line, below the swim platform. The only thing that sucks is I need a waay bigger hole than the cable for the plug to pass through.

zaverin1

You always drill cable hole above water line
seal
with 3m and route from
there

reneechris14

I did a transducer on my 342 this spring. Went in reverse till I got though the gel coat then flipped the drill to forward. Hold on to that drill the glass is had and thick. Maybe start with small and work up to 7/8" I did but it was tough to though.

zaverin1

Yes start small and gradually open the hole to the size needed. Use masking tape over the hole location. This will keep gel from chipping.

drill in reverse lol
just use good sharp drills 

Willhound

zaverin1 said:

Yes start small and gradually open the hole to the size needed. Use masking tape over the hole location. This will keep gel from chipping.

drill in reverse lol
just use good sharp drills 

Not sure why you find that funny, anyone experienced with power drills knows this tip. Has nothing to do with the sharpness of the bits. With slick surfaces (gelcoat, tile, stainless steel etc.) running the drill in reverse at a slow speed helps to set the hole location with less danger of the bit, hole saw, whatever, grabbing or skittering across the surface causing damage. Then start slowly in forward, gradually increasing speed to finish the hole.

MarkB

Drill hole ABOVE water line, and seal with 3M 5200.  Do you need the plug?? My cable went right into the hole and we loaded it with 5200 and then flossed it back and forth through the hole to make sure the 5200 was inside and covered the core. I don't think we drilled more than a 1/4" hole, maybe 5/16".

04FV270riverrat

MarkB said:

Drill hole ABOVE water line, and seal with 3M 5200.  Do you need the plug?? My cable went right into the hole and we loaded it with 5200 and then flossed it back and forth through the hole to make sure the 5200 was inside and covered the core. I don't think we drilled more than a 1/4" hole, maybe 5/16".

Its a pretty big plug that I have to feed through here's a pic

Glassguy54

You'd think the manufacturer would make some provision for attaching the plug end after feeding cable through transom so as to minimize the size hole needed for the installation. Cut & splice? One option maybe.

04FV270riverrat

Hopefully one of these will work, gonna go to 3/4” then try to wallow it out a lil more to get the plug through.

randy56

I'd use the hole saw if it were me.

LaRea

On mine, first I figured out the hole location by measurements on both sides (as high as possible).  Then I drilled a 1/8" pilot hole from inside to confirm the location.  Then I drilled the full-size hole.  I'm a measure twice, cut once kinda guy.  

zaverin1

I work for aam and did my share of drilling and machining 
tape it
do a small diameter spot drill and off you go

MarkB

Oh, plug is attached. Yes, unless you want to splice and reconnect (which I don't recommend as you can lose signal integrity), then you'll have to drill a bigger hole. Can you reach the hole from the inside. As others said, tape the location (to help minimize fracture), drill a pilot, and if you can drill most the way from outside and then go inside to finish the hole.  What you don't want is to be pushing on the transom as you go through from the outside in and you tear off the laminate on the inside.  If you can't reach it from the inside, then go light as you approach the interior wall.

04FV270riverrat

I drilled the pilot from the inside, then a lil bit bigger hole and went with 3/4” hole saw but from the out side and took it slow. It went much better than I anticipated. I just have a huge amount of sealant to fill it with lol.