Transom angle on 228 .. installing 1kw Airmar transducer

mous

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Hi
What is the transom angle on 228 2004 (Not deadrise angle).. i am installing 1kw Airmar T185M.. I need to compensate for transom angle using Shims..
Do you use shims? How many? Can you track bottom at speed?

Any real life experience in installing these huge transducer is appreciated.

Thank you
 

wrxhoon

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I have the TM 275, use one of the sims supplied .
I fish offshore mostly for Marlin and other pelagic fish, sometimes I drop deep at 1200-1500' as well. I can pick up fish at the bottom but I only drive slow when on the deep reefs.
I can pick up bait balls at speed on deep water, when there is bait around usually the predators are around as well.
I was thinking of installing one thru hull but decided on transom as I didn't want another penetration on the hull. I had the same in my old boat and worked well. I have 12" Simrad NSS evo 3.




GW transducer resized.JPG
 
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mous

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I have the TM 275, use one of the sims supplied .
I fish offshore mostly for Marlin and other pelagic fish, sometimes I drop deep at 1200-1500' as well. I can pick up fish at the bottom but I only drive slow when on the deep reefs.
I can pick up bait balls at speed on deep water, when there is bait around usually the predators are around as well.
I was thinking of installing one thru hull but decided on transom as I didn't want another penetration on the hull. I had the same in my old boat and worked well. I have 12" Simrad NSS evo 3.




View attachment 17700
Thank you for the info and clear photo .... you install one tapering up or down?
Thanks
 

wrxhoon

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Thank you for the info and clear photo .... you install one tapering up or down?
Thanks
The thicker part of the shim on the bottom. The ducer has to point straight down not on an angle . Transducer fitting is very critical if you want it to work well, at times it can be trial and error . If you fit this ducer on your 228 you have the advantage of knowing mine works very well . If you fitted the same as mine yours will work too. You have to make sure the bottom of the ducer is in water no part of it in the air otherwise it will not work well when under way. Install it where you think will work but make sure you bolt it in the middle of the slots so you can move it up or down. Don't install the the 5th screw until you have it 100% ( I never install the 5th screw ). These are big ducers and effect your boats speed and fuel burn, they also create a rooster tail .
Have a good look at the picture above and fit yours in the same position. As your looking at it from behind the boat the left side of the ducer is just bellow the hull.
Good luck and if you need more help/advice let me know and I'll try to help. Others closer to you maybe able to advice you as well. This forum is full of people that are eager to help others.
 

mous

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The thicker part of the shim on the bottom. The ducer has to point straight down not on an angle . Transducer fitting is very critical if you want it to work well, at times it can be trial and error . If you fit this ducer on your 228 you have the advantage of knowing mine works very well . If you fitted the same as mine yours will work too. You have to make sure the bottom of the ducer is in water no part of it in the air otherwise it will not work well when under way. Install it where you think will work but make sure you bolt it in the middle of the slots so you can move it up or down. Don't install the the 5th screw until you have it 100% ( I never install the 5th screw ). These are big ducers and effect your boats speed and fuel burn, they also create a rooster tail .
Have a good look at the picture above and fit yours in the same position. As your looking at it from behind the boat the left side of the ducer is just bellow the hull.
Good luck and if you need more help/advice let me know and I'll try to help. Others closer to you maybe able to advice you as well. This forum is full of people that are eager to help others.
Thank you for the great help .. Definitely, I'll use your photo to install the ducer ..

i am still not clear how far the ducer should project below the transom. Due to the deadrise angle of the boat, if i keep it 3 mm below waterline as recommended by Simrad (side close to the central line), it will be projecting much more below the transom on the other side!!

How far did you install the transducer below the the transom measured on the side close to central line?..
Thank you for your support
 

wrxhoon

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3 mm ? Now you are talking in my language....1/8" will be fine , have someone to hold it in place for you, bracket installed , when you are happy take a pencil and mark the slots on the transom then drill in the middle of the slots so you have adjustment if you need to move up or down. I usually drill in reverse to start with so I don't chip the gelcoat, one size bigger drill bit, then use the correct size bit to drill into the core but whatever works for you .
The distance from the keel is not critical as long as it is not where the clam is or near a streak and not too close to the central line so you don't get prop interference when reversing, won't work well when reversing trough.
It is night and raining here now let me know if you still want me to measure and I'll do it in the morning.
 

mous

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No need to measure it thank you.... that is more than enough for me at the moment... I'll install it next weekend.

We use metric units in the Middle East... By the way, I bought the whole system online from a Simrad dealer in Australia... my first time to make an online order from outside USA. Experience was average many things can be improved.
Received wrong fuse size with both Simrad nss evo3 .... the correct one is hard to find locally ... not mistake of the dealer but manufacturer (Simrad).