Official 2003.5-2008 340 Sundancer Thread

Has anyone done a step by step write up on replacing engine impellers on the 8.1’s ? I could have swore I saw it on here at one time, thanks!

Do yourself a favour and just remove both mufflers on both sides. It will make your life sooo much easier. Some say you don't need to remove starboard, but trust me. Get it out of there before you start. The job will go much faster. You'll need a deep socket wrench to get at some of the bolts. Give me a shout if you get into any specific issues.
 
Do yourself a favour and just remove both mufflers on both sides. It will make your life sooo much easier. Some say you don't need to remove starboard, but trust me. Get it out of there before you start. The job will go much faster. You'll need a deep socket wrench to get at some of the bolts. Give me a shout if you get into any specific issues.

This is a perfect example of the saying "sometimes more is less".
 
Do yourself a favour and just remove both mufflers on both sides. It will make your life sooo much easier. Some say you don't need to remove starboard, but trust me. Get it out of there before you start. The job will go much faster. You'll need a deep socket wrench to get at some of the bolts. Give me a shout if you get into any specific issues.
thanks so much!!!
 
Any of you guys replace your fresh water system pump? Mine has been cycling off and on. I did manage to find a small slow leak leading to the hot water heater which I repaired with silicone, but the cycling is still happening ...albeit much less frequently. If you did replace, what did you replace with? Was thinking about something like this:

https://www.amazon.ca/Shurflo-2088-...?keywords=rv+water+pump&qid=1587401402&sr=8-7

I was chasing this problem around last summer. I noticed that when I turned on the cockpit sink, I would get an initial blast of hot water then cold. That lead me to the check valve going into the hot water tank. It was shot and not stopping any water in either direction.

https://www.amazon.com/gp/product/B00K24EA3M/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

and my relief valve was leaking so I replaced that.

https://www.amazon.com/gp/product/B000N9PRKG/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Well, that lead me to my mixing valve wasn't mixing any longer which may have been because the check valve wasn't operating as it should have. I can't find the link for the mixer but it looks like this and it sits next to the hot water tank. This was not the one I used, it just looks like it.

https://badger-pipe.com/products/mi...e&utm_medium=cpc&utm_campaign=google+shopping

I also suspected that the strainer may have been allowing air into the system so I replaced that as well.

https://www.amazon.com/gp/product/B000V2W0GE/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

And lastly for good measure, a new pump.

https://www.amazon.com/gp/product/B00C1M6B1C/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

The leak was corrected and no more cycling. I also bought an accumulator tank but haven't installed it yet because I was so thrilled the air leak was gone.

https://www.amazon.com/gp/product/B00C1M6B1C/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I think I am going to do that after a couple other maintenance projects this spring. Sounds like that would reduce cycling as well. I bought all these parts and more together so I didn't have to make repeat trips to the boat.
 
I'm wondering if there is someone on here that has 2003-ish, or close to but not older, Mercruiser 8.1S engines AND have upgraded your electronics to Simrad. And, if all is working well for you, could you possibly go into the settings and export your personality file and provide it?
Well, after upgrading to the Simrad GO9XSE, I discovered that the old Smartcraft unit could have been placed in a secondary mode, and the new gear could have pulled all the proper settings. Well, that's great, but too late now. Too bad Simrad/Mercury will not provide the personality file to common folks, just install vendors get it. So perhaps we can work around that here??? Thanks!
 
Hello all my thru hull transducer is leaking and my yard said they can't get it out without destroying it. has anyone replaced their transducer? I'm trying to figure out what I need to purchase to replace it.

I have a 2006 with the Raymarine C80 system with DSM300 sounder and smartcraft SC5000 with 8.1 Vdrives

the transucer is the one with the plastic ring dead center in the V just forward of the engines.

also does the transducer cable run all the way to the DSM behind the dash or is there a connection in the engine compartment to plug it in?

thanks
John
 
If you did not order the impeller yet - try South Shore in Massapequa or Freeport Marine. Shipping delays have been horrible these days.

-Kevin
Thanks Kevin I wound up getting them from pearl grey. They had them in stock
 
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So I have a pontoon in florida with a garmin 742xs chartplotter on it. I brought it and the mercury gateway with me to michigan (for the summer) thinking I maybe able to use it on the 340 So far, after replacing the original 4 way with a new 6 way junction box, and making a new gauge panel out of aluminum, I now have an alternative source of engine info as well as another chartplotter. also went with a carbon fiber wrap over the new and existing panels. Come fall I'll pull the garmin and take it back to florida for the winter.
5-12-20 082.JPG
 
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anyone else terrified to start their generator this year? i did manifolds and exhaust two years ago on the motors, but never done anything to the generator heat exchanger or anything. just scared its gonna fill itself up with water. i dont know. have had the boat home for two weeks and yet to start it lol
 
I know what you mean, but start it up! Generators and AC units need to be run periodically to stay running when you need them. And if there is a problem, better to know early in the season.
 
Has anyone ever added oil to their steering mechanism? Not having any issues but when I open the fill hole there's no oil in there that I can see.
 

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Has anyone ever added oil to their steering mechanism? Not having any issues but when I open the fill hole there's no oil in there that I can see.
I’ve never done it on my boat but have done it on other types of boats. It’s hydraulic so if u have no problem with the steering then leave it alone. If u start to have problems there’s a way to fill it, then turn the wheel all the way in each direction to burp the air out of the system
 
Has anyone had starting issues and found it to be the 90amp fuse on the solenoid?
I’m getting power up but won’t crank.
 

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