4.1 transducer placement

[dirty dog]

Hi all just after some advice on where to mount the transducer for a HDS 5 unit on a 4.1 poly any ideas please.
wayne

[DvrDve]

below water level is allways good

m8 my hds 5 ducer- after a lot of tries sits right in front of the prop/skeg and to the right
i have it on a lil slide up setup so the trailer skid doesnt stuff it when trailering, but work out i can just swivel it up on the "kick up function" dont overtighten the nut that hold the ducer in the bracket
hope that helps -sadly cant send u a photo at moment
wait till u see it in thewater m8 -they are phenomenal
this was the only place she would hold bottom on the plane

[MikeEng]

My dealer told me not to put it in front of the skeg as this causes turbelence for the water intake of the motor. It can damage your motor and would invalidate your warranty.

Mine is mounted on the right hand pod. It does get some sidewash from the motor unfortunately. It still works very well giving me some excellent results as can be seen by the attached photos.

You'll notice it says only 0.4m deep. This is caused by the propwash I think.

MikeG

[DvrDve]

mike
m8 what transducer u got a 2 m wide x 1m high one?
there is no bloody way a transducer 4cm wide and in a teardrop shape can cause that much turbulence

get yourself another dealer-next thing he ll sell u a new skeg rather than replace the oil in the gearbox, ad a new powerhead instead of replacing sparkplugs
seriously m8 thats a load of croc- and i dont mean that personal etc
25 years on commercial boats -thats a 1st for me- i had a good giggle tho
i dont get any sidewash and a perfect picture at all speeds
who s the dealer if u dont mind

[MikeEng]

Bo at East Kimberley Marine. I know him and trust him. He told me this because he believes it, not because he is trying to make money. Although I do suspect it may have been the easiest option for him too...

I wouldn't dismiss it outright. I know a lot about pumps and pumping theory and know that even a small amount of entrained air is enough to cause big issues for an impellor. Even for rubber impellors like outboard water pumps. When they set the motor up they do their best to ensure the water pickup is going to be in the best flow possible. In most cases the cause of early deaths of outboards is poor cooling (admittedly usually operator error though).

Those transducers are not large, but you must admit that they do disturb the water. Especially so at high speeds when the motor needs the most amount of cooling and the water pump is running fastest.

In so saying, I think that putting it even 1/2 foot to the side of the motor may be sufficient to prevent the motor from sucking up the disturbed water. I intend to keep investigating my options. I still may move it and if so, it'll be done with the most amount of information possible. As such I don't see any issues sharing information passed to me in good faith.

Bo did suggest I fit a plate in an attempt to prevent sidewash. I'll be investigating this option too.

With your setup, have you ever stuck your head over the back to have a look while at flat knackers? Do you have much surface noise on yours? Comparible to mine(mine was taken in the Cambridge Gulf with *very* dirty water)?

Polymack was looking at this location
http://www.polyboatowners.com/2010/vb/attachment.php?attachmentid=873&d=1285246948

When I am back this W'end I'll take a photo of my setup and flick it through.

Cheers
MikeG

[DvrDve]

mine is on other side as polymack so stb vs port 2 inches to the right of the most right bung -pretty much a mirror image of polymacks
ms holding tiller me with head over the back was done on all 4 places i tried
at full kettles transducer hardly sits in the water and the disturbed water is still about 2 inches above water intake
with virtualy no aeration- by the time it gets to skeg that trail seems to ahve no air in it, i get no picture disturbances right thru to 25kn where she tops out - only a lil 30 hp
the wash from the sounder seems to be above the cavitation plate

i tried 3 other positions - luckily never fully penetrated the outside skin, fill welded the old holes
mate this is the only place i got no noise from motor at all speeds
picture is clear as day, motor still running and she sometimes do up to 2 hrs flat stick out trawls then flat stick back, on replacing the impeler 3 weeks ago showed no signs of wear etc and looked as good as the new one- i know one cant really tell by eye, but there was no wear marks etc on impeller or housing
i hear the theory of air and impelers and believes it, but at full kettles there is so much water pressure, and so much water going past that i believe there is no issues
so choice as i see it, theoretical issues and a clear picture or no aeration and a dirty pic mmmm
btw the poly has been all around king sound and the sounder was clear,derby to horizontals falls to derby , (towed most of the way) but at least 3 -6 hrs fishing every day

[MikeEng]

Mate, that sounds fantastic. If you get a chance to chuck some photos up I'd like to copy- *ahem* borrow ideas from your install. :D

Do you have both transducers there or just the structure scan?

Sorry to hijack your thread DirtyDog. Guess its all on topic though.

Cheers
MikeG

[DvrDve]

m8 i do not run structure scan on the 4.1 only on my big boat
i had it on for a brief period -but on the opposite side -port
again in front of the skeg- only place it would work well
S/S is in my opinion for inland waterways or really flat good days
i am away from home for next 2 weeks will try to post as photo then
supposed to be on a year holiday and working more now than when i was full time employed
however leaving just after chrissie for tassie for 3 months

[MikeEng]

S/S is in my opinion for inland waterways or really flat good days

That makes it perfect for the 4.1 ;)

As I am in Kununurra, inland waterways, rivers and really flat good days are all I see :D

I think I might move it over this weekend. I'll report back with some photos for you DirtyDog. Are you looking at the structure scan as well mate?

Cheers
MikeG

[DvrDve]

they suggest s/s and normal transducer within, i think, it was 2 ft as they do communicate somehow with each other
so maybe1 on port 1 on stb on either side of skeg

[Pirate Pete]

I have a 5 on my 5.3 & love it. Im also thiking of getting a new power lead & transducer & fitting them to the kayak Im building.

[MikeEng]

Within 2ft is for the overlay feature I believe. If it isn't within 2ft the overlays won't match.