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  Topic Review (Newest First)
09-24-2009 06:30 PM
Originally Posted by krozet View Post
Deposit paid last week, final payment tomorrow.
Congratulations.... hope the rest of the process goes smoothly for you.. the engine swap may be easier than the paperwork! Best of luck.
09-24-2009 05:47 PM

Especially for auxiliaries, diesels suffer most from not being run for sustained periods at power. Having said that different diesels have service ratings. Generally the manufacturer can advise you on this and given the specs for your boat they can make a recommendation of the power best suited for you. Where the propeller comes in is matching its' performance curve with your engine's Shaft Horse Power curve (from .94 to .96 of BHP or Brake Horse Power which is what's normally in the specs.) performance, for sailboats the goal is to get the curves to match at normally 90% power. The prop's diameter is normally limited by the hull or skeg clearance from the blade tip. You need at least 15% of the blade's diameter for clearance. The next issue is blade pitch. Too much pitch and your engine won't get up to speed, too little and it will overspeed at full throttle. After pitch comes is blade area, too little area and the prop will gravitate at full power. So if your diameter is limited you may have to go from a two bladed prop to a three bladed prop to get sufficient blade area. Propeller manufacturers will calculate the right prop given you boat and engine specifications. Michigan Wheel is a good one for this.
A note: Some manufacturers show both BHP and ISO 8665 power curves. the ISO deals with controlled testing conditions which I don't know much about. Prop manufactures seem ot with using the BHP number for thier calculations.
Again David Gerr's book has all this info
09-24-2009 02:38 PM
Originally Posted by Faster View Post
So - Robert... have you done the deal on the boat yet?
Deposit paid last week, final payment tomorrow.

The current owner scanned and emailed me the Florida title of the boat, and since that title is in the name of the previous owner he sent me the sales contract from the previous owner to himself. The current owner never transferred the title as he lives overseas and didn't know if he was going to sell the boat or sail it home. He scanned and emailed me a sales contract from himself to me as well as an example letter for me to use too get the title canceled in Florida so I could start the process of getting the boat registered in Canada. I have emailed the Florida Department of Highway Safety and Motor Vehicles 2 days ago asking them what I need to do in order too get a letter of cancellation for the boat title from their system but have yet to hear back from them. If I don't hear from them today I will have to call them.

I almost started a thread about the whole process but thought I had started enough threads in the last week and didn't want to irritate anyone.

Guess I will be the proud owner of an expensive hole in the water in the next couple days.

09-24-2009 02:01 PM
Faster So - Robert... have you done the deal on the boat yet?
09-24-2009 01:52 PM
Originally Posted by Waltthesalt View Post
Before deciding on a significantly larger engine I recommend checking out Dave Gerr's "Propeller Handbook" from the library. Overpowering can be problematic for the diesel if that means the engine will not normally be run at 80-90% full load.
I'll have to show my ignorance of Diesel Engines here but wouldn't it prolong the life of an engine if it didn't have to run at 80% to 90% load on a consistent basis? I thought I would be ahead of the game If I had a 30HP engine on a 12,000lb boat with the proper propeller.

But that's why I'm here, to learn.

Thanks for any feedback;

09-24-2009 12:11 PM
Waltthesalt Before deciding on a significantly larger engine I recommend checking out Dave Gerr's "Propeller Handbook" from the library. Overpowering can be problematic for the diesel if that means the engine will not normally be run at 80-90% full load.
09-20-2009 06:08 PM
Originally Posted by DwayneSpeer View Post
If the old engine is raw water cooled don't even think about a rebuild. The old engine, even if rebuilt is just waiting to fail due to something inside corroding thru.

I don't know about all the manufacturers but when I repowered with a new Beta they made engine mounts that fit onto my old engine bed. I just had some adapter plates made so that the new mount bolts and the old bolt holes worked. No big deal and definitely no rebuilding the engine mounts!

Also, I did all of the installation work on my project and I'm just a back yard mechanic. The two things that were a bit unusual were that the new engine turned opposite of the old and the throttle hookup was also backwards. I now run my transmission in reverse for forward, no big deal for a Volvo Sail Drive, and hooked the throttle up backwards also. Both readily achievable.

The bottom line. Don't give up on a new engine of a different make until you have looked into it very carefully and are sure it just won't work.

Current engine is a fresh water cooled engine with a heat exchanger.
09-20-2009 06:04 PM
krozet I have a line on a re manufactured Yanmar 3GM30F. The info I have received is that the shop has replaced everything except the block. The price is $3900 and comes with a two year inclusive warranty.

I can't find a new 3GM30F or 2GM20F as these have been replaced in the Yanmar catalog with the 3YM20 and 3YM30 and I can't find a price for either of these engines.

For new I have found a Yanmar 3JH3-E that has 40HP but the weight is 100Kg more than the current engine. A couple Westerbeke 30B three's that weigh less than the current engine but output 27HP. A Volvo Penta D1-30 with 29HP that weighs just a little more.

I can't seem to track down an active owners group for my boat so comparing setups isn't going to be possible.
09-20-2009 04:08 PM
SailorNate I second Jeff on this one. I have owned two Volvo motors now, I never would have owned the second if I didnt get a 25K discount for it rusting there. The high price of labor and parts make rebuilding an engine a losing bet. Look around, find the owners group for your boat and find out what works well for your setup.

09-20-2009 02:57 PM
Go new, dont even think about rebuilding

Go with the new.

Check out Beta Marine and other suppliers.

Select size and footprint to fit existing mounts, should be easy.

Select transmission to get right hand vs left hand.

More HP will require different prop. Don't mull over it, just get the new right prop.

You'll be shocked at how much better the new motor, new prop, and new HP level will improve your life aboard.

Ensure closed loop cooling.

Tear down the old motor to reduce weight and chuck it over the side (lol, only if onthe hard). That was the 2nd best day of my boating life, getting rid of the volvo MD7A. what a wreck that motor was.

lots of rugs, and elbo grease and a few beers for friends will get the new motor in place.

Rebuilding that Volvo was the biggest waste of money I've experienced, second only to the stock market. lol
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