Yanmar 2V78 Saildrive

Discussion in 'Diesel Engines' started by sgancarz, Sep 28, 2015.

  1. sgancarz
    Joined: Sep 2015
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    sgancarz Junior Member

    Spent the day at the machine shop yesterday and made real progress on the mount. Here are some pics with the engine mounted to its new mount.

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    Next project is to make the bracket for the raw water pump. With that, the mount will be complete with the exception of paint. Then its on to finishing up clearing out all the filler wood in the original mount, so that the drive leg can be lowered into place.
     
  2. sgancarz
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    sgancarz Junior Member

    Time for an update!

    Spent a couple of hours yesterday removing the rest of the wood from the OMC mount. Originally was going to just sand it until the lower unit would fit and then was going to seal in the remaining wood with fiberglass. Well I couldn't get the lower unit in, so I started chiseling away at the area with a screwdriver. The resin began popping away from the mount. Took me a good hour or so, but was able to remove all of the wood and excess filler.

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    Once all was out I was able to dry fit the lower unit in the boat.

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    Felt good to see the lower unit sticking out of the bottom of the boat.

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    Finished the bracket for the raw water pump today. Tried my hand at TIG welding. Let's just say, I shouldn't quit my day job. Burned through it several times. Had to have a friend fix/finish it for me. It's not beautiful, but it's functional.

    It's finally looking like the original drawing.

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  3. sgancarz
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    sgancarz Junior Member

    Time for an update on the progress.

    Had to remake the pump bracket due to a slight design flaw on the original. My machinist friend felt that the original design had the potential to bend once the belt was under tension and running. Probably wouldn't have been instant, but in time it would have probably bent. So for reliability reasons I completely remade the bracket with additional reinforcement.

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    Next design change is in the coupling. A suggestion was made in another forum to look at the Dodge Paraflex coupling. After much research and time at the computer modifying my drawings to check clearances, I have decided to go with the Paraflex instead of the Lovejoy. Here is my Sketchup drawing with the Paraflex coupling in place.

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  4. sgancarz
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    sgancarz Junior Member

    Test fit the engine on the mount this evening to look at all the final clearances. It is just mounted on a test table I built last night to be able to do the test fit. Although I have to say everything looks pretty good. I think all my planning and time spent drawing everything out in Sketchup has really payed off.

    The Paraflex coupling actually gives me more clearance and will allow me the ability to change the raw water pump belt without having to move the engine. So yesterday I went ahead and ordered all the various pieces for the new coupling. Should have all the pieces by this weekend. Unfortunately don't think I will be able to work on it at all this weekend as I have out of town house guests.

    Anyway here are the pictures of the engine sitting on the mount.

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  5. sgancarz
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    sgancarz Junior Member

    I test fit the coupling and performed a dry run of the complete shaft alignment proceedure. I then disassembled the coupling to see how easy it would be to change a belt. Sitting on the stand in the garage was not too bad, however I am sure that doing it while laying on my stomach in the lazarette will be a completely different story.

    Here is a picture of the Paraflex coupling installed. I still need to complete the pulley to drive the raw water pump.

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    Currently finishing up the painting of the lower unit and have permanently installed the Iso-ring on the lower unit with 3M 5200 sealant. Need to let it cure for seven days. At that point the lower unit will be ready for installation. I then need to do a final sanding and paint job on the mount assembly.

    Still waiting for warmer weather so that I can finish cleaning and painting the lazarette. Also need to install the thru-hull for the raw water intake and the new fresh water tank.
     
  6. fredrosse
    Joined: Jan 2005
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    fredrosse USACE Steam

    Looks like a nice job. good luck with it. You may consider parking the spare water pump belt already fitted around the engine shaft. If it can be placed without rubbing against any rotating part, it would make future replacement a far easier job.

    Also be sure to use Locktite Threadlocker on all the nuts, even with lock nuts the stuff is good insurance.
     
  7. sgancarz
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    sgancarz Junior Member

    Well the lower unit is finally in. I splash the boat first thing tomorrow morning. Still quite a punch list left before I can install the engine. But, hopefully there are no leaks tomorrow. Here are some pics of the lower unit installed and ready for the water.

    Also I obtained a NOS OMC folding prop earlier this month on ebay. This is a great addition to the project.

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  8. sgancarz
    Joined: Sep 2015
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    sgancarz Junior Member

    Got the new instrument panel back from the laser engraver. Had them do all of the cutouts for the gauges, lights, and the ignition switch as well as the engraving for the lights. I have installed the guages, lights, and ignition switch, however I still need to make the wiring harness. At least this puts me one step closer. Now I need to figure out if the audible alarm will be loud enough mounted in the lazerette or whether I need to cut slots in the panel for the sound to make it through. Guess I will just have to wait and see.

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    Also need to get the cooling system work done. I am waiting on the soldering materials so that I can finish up the modifications to the fuel tank. Once that is done, I will begin the work on the cooling system and then on to the wiring. After that I should be able to accomplish the final install of the new Diesel Engine.
     
  9. jruhnke
    Joined: Jun 2016
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    jruhnke Junior Member

    Like your Saildrive Solution

    I really like your design/solution for the OMC Saildrive. I have a 1979 Sailboat with an OMC Saildrive and am getting worried about its eventual replacement. Yanmar makes a Saildrive with a 2gm diesel mounted to a Volvo Saildrive Leg. The problem is that I'd have to cut and relocate the hole in my sailboat, to a slightly different location. Your solution of mounting a Vertical-shaft diesel to the existing OMC Saildrive Leg is Brilliant! I've looked to see if anyone else has tried it, but haven't found anyone.

    If your solution works, I might try it too. It's cheaper than cutting new holes in the hull. One problem I've discovered though, is that the Yanmar V-twin shaft-drive diesel is being discontinued. I might still try to find one. Or... perhaps try connecting a gas powered, vertical-shaft, water-cooled engine to the "set-up" like you are doing. The Lower Unit has never failed.

    I do have a few specific questions; -What is the size/dimension of the shaft that you put on the Lower Unit, that goes up and "meets" the engine/shaft?
    -Where did you get the Paraflex Coupling? -Do you have any problems with water getting into the cylinders and "Hydrolocking" the engine? Or... does the fact that you elevated the engine/mounting & are using a separate water-pump solve that problem?

    Good Luck with your installation. I think you have a really good solution to the OMC Saildrive issue. I hope it works. Please keep posting.
     
  10. sgancarz
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    sgancarz Junior Member

    jruhnke,

    Glad you find promise in my little experiment. There are actually three of these engines on ebay right now. The engine is currently out of production, so getting parts in the future may be challenging. But there were many of them produced and quite a few of the parts can be sourced directly from John Deere. I believe there were even more utilized in Europe, so another possible source.

    There is another individual that did do a conversion of a Baldwin Saildrive to a Briggs & Stratton air cooled engine. Not nearly as elaborate as my Frankenstein though. I just wasn't interested in staying with gasoline. Just don't like the volatility. Plus diesel is much more efficient.

    The input shaft to the drive is the original 5/8" shaft that I milled a 5/32" keyway in. This was to match the industry standard for a 5/8" shaft. I then obtained the Paraflex PX50 coupling components and the appropriate taper-lock bushings for the 5/8" and 1-1/8" shafts.

    I have not yet completed the install, so unfortunately I have not had a chance to run the engine in the boat. The engine will sit higher than the original OMC and the water injection will not enter the exhaust until the mixing elbow, so hopefully should preclude any issues with the "Hydrolocking" experienced on the OMC's.

    Been a pretty busy summer so haven't had the time to devote to the project. Hoping to get some time soon. Getting anxious to get this thing up and running. Tired of the old outboard hanging off the back of the boat. Plus I am looking at a used Zodiac that I plan to run the outboard on, so need to free it up for that.

    I will continue to update the forum as I make more progress.
     
  11. jruhnke
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    jruhnke Junior Member

    Thanks for response

    Thanks for the response. I read an article in Good Old Boat magazine about the Baldwin replacement to a Briggs & Stratton Lawnmower engine. He said it worked great. Because it's "air-cooled" he doesn't have to worry about any Hydrolocking issues.

    I don't want to convert to an "air-cooled" engine. I like your idea much better. Also... the idea of using the existing OMC Lower Unit, really is appealing.

    So looking at the Diesel conversion that you are doing. It looks like you have the additional "weight" issue resolved, with the engine sitting on that metal bed. Are those actual "engine mounts" on the frame? Or did you rig something with bushings? They look like bushings for an automobile.

    I'm assuming that the rpms of the diesel will be similar to the OMC engine, but perhaps a bit slower. It looks like your prop will work pretty well. If you find your new engine running at a slower rpm, you could have a modified prop made. That said... I've found that I've never ran my OMC at full throttle. It was never needed and would have shaken the boat up too much. So I think a slightly lower rpm might be advantageous.

    Another question I have regards the engine dimensions itself. Do you know the actual dimensions of the engine? The space on my sailboat can handle a yanmar 1gm without any modification. But I'd have to cut the sides to make room for the 2gm. There is room for a larger engine than my OMC power head, but I would prefer not having to cut the side access. Could you list the height, the width, and the depth of your V-twin powerhead?

    Thanks for posting. I'll keep monitoring your progress.
     
  12. sgancarz
    Joined: Sep 2015
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    sgancarz Junior Member

    They are Vibration Isolation Mounts. The specific ones that I purchased were part number 351-50-30-M10-ES-55.


    The RPMs are actually pretty close. I found a spec that showed max RPM on the OMC at around 3700 and the Yanmar has a max RPM of 3600. I find that most people run their diesels between 2000 - 2500 RPM, which is where I think this one will run pretty good at as well.

    The engine dimensions are approx. 23 5/8"L x 15 5/8"W x 14"H. My base uses 5" channel plus the mounts and the 1/4" engine mounting plate giving me an overall height on the engine of approx. 19 1/2".
     
  13. jruhnke
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    jruhnke Junior Member

    Checking out the measurements

    Thanks for the engine measurements. I'm going to my sailboat to check out if it will fit. I'm pretty optimistic about the size/dimensions... even with the base and plate. I can see why you chose the Vertical-shaft version, it's definitely more compact than the 1gm and 2gm engines.

    Another question that comes to mind has to do with the exhaust. I can't tell where the exhaust port comes out the engine. Is there 1 or are there 2 exhaust ports, that connect up to the muffler? Are you planning to put your mixing elbow on the exhaust port(s), or after the muffler? The mixing "stack" on my OMC is pretty high, before it goes to the wet-exhaust muffler. I've seen some that are low too.

    If I go with a system like yours, I would probably copy your water-pump/pulley mechanism as well. I have a through-hull I can pull the fresh water through to the intake pump (like yours).

    I realize that you might not have hooked up the engine yet, while the boat is in the water... so you might not have that figured out yet.

    So I guess the next question would be how do you plan to hook-up the exhaust mixing elbow? Before, after, or instead of the muffler?

    Please let me know what you end up with. This is getting interesting.
     
  14. sgancarz
    Joined: Sep 2015
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    sgancarz Junior Member

    I have a more detailed post in the Paceship Forum. In there I have a rendering of the exhaust pipe that I will need to manufacture. The exhaust will be a dry exhaust up to the mixing elbow, where the raw water will be injected prior to the muffler. I believe the height of the mixing elbow will be pretty comparable to the exhaust tower on the OMC.

    Due to the aluminum block on the 2V78 engine, I will be setting up a heat exchanger to ensure adequate anti-freeze in the block to prevent issues with freezing in the winter. Don't want to take a chance of any pockets in the block that might not get enough anti-freeze during winterizing.
     

  15. jruhnke
    Joined: Jun 2016
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    jruhnke Junior Member

    Mixing Elbow

    I looked up the other forum to see the rendering of your exhaust tube, Thanks. Your rendering looks good. I'm not sure where you will have it fabricated, perhaps you could post that info too (afterwards)... it's a little too complicated for me to make. I do have some thoughts I'd like to pass your way.

    -The height of the mixing elbow should be about the same height as your OMC stack was. There is a formula you can use to figure the height in relation to the water-level, waterlift muffler... etc. If it's the same height as before, you should be okay.
    -Over time, you will get carbon build-up in the mixing elbow, even if it's stainless steel. Make sure that you can remove the elbow (from time to time), so that you can clean the inside. I've used a wire brush attached to a long drill-bit.
    -There is a really good article in Good Old Boat on this subject. Jan/Feb 2015 (pages 32-35). Yanmar makes a replaceable elbow that they use on their 1gm and 2gm engines. Your solution should work fine... but theirs might be a little easier and cheaper. You could use their elbow on your fabrication... just a thought.

    In regards to your heat exchanger; -Many people use heat exchangers successfully. They are especially useful on sailboats that are used on the Ocean. I'm planning on only keeping mine on freshwater. I've always drained "all" the water from the engine, prior to winter. Most of the Sailors I know here, take a jug of "antifreeze" and connect up a small diameter hose. They then invert the jug (held just above the engine level), and put the hose/tube up to the water intake. They then run the engine and feed the antifreeze directly into the block. That way... there's no "water" to crack the block.

    -Your heat exchanger solution should work well. I thought I'd pass this info along your way... make whatever use you can from it.

    I also looked up the example you gave about the Baldwin-Saildrive. It turns out that this is a different example from the one that I read about. In your example... he used a Briggs & Stratton Lawnmover engine and connected a "wet-exhaust." The example I read about, the guy (different person), connected a Briggs & Stratton "air-cooled" engine to the Baldwin-Saildrive. The article I read was Good Old Boat Issue #103 (July/August 2015, pgs 20-22).

    I checked out the measurements on my Sailboat and it looks like it could easily handle the Yanmar (2V78 vertical-shaft), diesel. It's compact, strong, and lighter than other diesels. I don't know why they are being discontinued. Are they reliable? Yanmar is a well-known diesel manufacturer. I'm sure they will supply parts and service for many years.

    Thanks for posting. I will keep monitoring.
     
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