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35-2 engine replacement

kdr

Junior Member
I am replacing my a 4 with yanmar 3 gm. My engine is located in the salon. Has anyone done this replacement before, particularlly interested in installation of new stringers.
 

Bill Robbins

Member II
Wow. Big Job!!
I did it though, in about 130 hours. And I am very happy I did. Go for it.
I replaced the a-4 with the Yanmar 3GM too. I have the same MKll with salon positioned engine.
In regard to the stringer. The old stringers for securing the motor mounts were rusted out badly. It is amazing the engine did not just fall out. I am sure it would have sooner or later.
The stringers are secured to the hull by "flat bar" witch is inlayed into the hull with fiberglass. The glass that secures the flat bars are not part of the structural hull. They simply glassed over the bar on top of the hull to secure the bar down. I had to chip out all of the covering glass to pull out the bar, which was rusting up into the fiberglass. Once this is done you are left with a "bare hole" to which you can construct your new engine bed.
The old engine bed, even if in good shape will not accommodate the 3GM.
One more thing to think about (wow that is an inaccurate statement). If you follow the line of the shaft to locate the new position for the engine, the engine will be located much higher than the a-4. (about 5 inches!) The Yanmar is taller than the a-4. I did not like this because of the setting, so I used a "Aquadrive." It is a CV joint that allows the angle between the shaft and the transmission box to be up to 15 degrees off. This allowed me to align the engine down a bit so the engine now only sits up about one inch higher than the old a-4. I am now in the process of raising the rest of the dinning area up to the level of the new engine box. Also the Yanmar is a bit longer than the a-4. I had to cut away a bit of the cabin sole in front of the engine to make room. I used part of my new engine bed to help support the sole since I cut the supportive combing away.


Couple more tidbits,
I used clear narrow vertical grain doug fir for new stringers. I soaked them with smiths clear penitrating epoxy. I then "glued" the stringers to the bare hull with polysulfide rubber, also made by smiths. Polysulfide rubber is extreemly strong and is flexable so fibration from engine does not transfer into hull as much. Glassing the stringer to the hull is the most commone way though. There are several ways to design the engine bed. An "H" shape is the most commone design. Using the Auquadrive really made the instalation of the engine bed easy since the exact position of the bed did not need to be in allignment with the shaft.
I have to go to work now. Keep e-mailing with questions, glad to help.
Good luck

Have
 

Bill Robbins

Member II
Dear Bill,

Thank you for your response, you are a life saver. Is the Polysi the only thing holding the stringer in place?. Also have you thought about a water heater and a place to put it.

What size propeller shaft did you use. I would like a 1" but have not checked the size of the shaft log or strut to check fit.

Hello Kevin,

Yes, the only thing holding the stringers in place is the polysulfide rubber. This has raised eye brows from many old salts, but it is holding well and I am confident it will perform in the long run too.
If you choose the polysulfide approach make sure you understand the principal of the thing. You need to prep area correctly, and make sure all mating surfaces have the proper amount of polysulfide between them. I also used a "modified" H configuration for the engine bed to accommodate the special needs using polysulfide. Fiberglassed is easier and more forgiving. Your choice!

I did not spend the money to enlarge the shaft. There is however, in my boat, enough room to accommodate a one inch shaft in both the strut and shaft log tube. I would recommend replacing it if you can afford it. I will someday. I am using a larger (I can get dimensions for you later) three bladed prop with a bushing to accommodate the small 3/4 inch shaft. It works great. It is important to get a properly fitted prop. The prop guy in my area new from experience what works on an E-35 with the Yanmar 3GM. He was right and I am glad I listened.

Be aware of several things too. Your fuel tank is probably galvanized. Diesel fuel will flake off the galvanized surface and clog fuel lines. You will need to replace it with a new Aluminum tank. The old tank is sized EXACTLY to fit in position and to be removed via the stb. cockpit seating hatch. When replacing tank get an exact fit, do not enlarge it without careful thought or it will not fit back in place.

The standard engine harness worked fine for my panel located forward in the cockpit. I have a tiller. If you have a wheel with panel in the aft section of the cockpit, you will need the extension I think. I have about 1.5 feet extra wire left over from current position. If you can tell me where you plan to locate your panel I can estimate from my existing set up what your needs might be.
To affix the engine panel, I fiberglassed the existing panel area closed. This made one solid section to cut out the proper size hole for the new Yanmar panel.


Are you going to do the work yourself or have someone do it for you? Keep in touch, I would enjoy sharing what I know with you. There are a great many other questions I think you might have. (exaust, electrical starter wiring, alignment, new raw water intake through hull, fuel filters,.....ect ...ect...)
Others on the website will be helpful as well.
I am going to post this back to the Ericson board. I think others might appreciate what you are going though. Keep in touch.
 

Bill Robbins

Member II
Bill,

I am now starting installation, stringers are in place. Before I drop in the engine, four questions.

1. did you use the existing thru hull
2. where did you place fuel filter
3. where did you place raw water filter
4. how did you route, and what did you use for the exhaust.

thank you very much

Kevin,
Things must really be moving along. Hope this is not too late. I have been away "sailing."
More on that story later! (I lost my mast)
In short:
I used the old through hull. I think it is barely sufficient. I have heard reports of Yanmar replacements not getting enough water during hard long trips, and it overheating. I will replace mine next haul out. I have had no problems even running at 3,000 rpm' s for 6 hours. I just did this last week.

I put the fuel filter port side, just forward of the tank on the vertical quarter birth wooden side. I placed it as low to the hull as posable for best flow with a low tank, but still have access to it for changing filters ect...
I have the small newer model racor spin on type. The filter fits between the upper housing and the lower plastic viewing cup. I think it may be model 400?

I should have a raw water filter. I do not. Let me know what you decide! I may be doing the same soon.

The exhaust really needs to be thought out well. If not, water can siphon back into the motor's cylinders and or ocean waves hitting the transom force water back up though the system.
First, only use quality hose and joints. Do not use PVC water hose joints like many people do. Under good conditions they work, but soon as your motor runs hot or some other thing happens you will end up blowing all the water into the bilge and worse. I am trying to remember the name of the proper joint. It is made of fiberglass I think. They look like it. They are available at most marine stores. Also use approved fuel line.

I used a Vetus "muffler." I think it is the smallest one they make, but am not sure.
The system flows like this. The main wet exhaust hose comes out the motor, under the cabin sole to the Vetus which is located just aft of the cabin sole, near the strut bolts. This seems to be the only good place for it that is lower than the exhaust manifold and amid ships. The hose is then run upward out of the Vetus toward the underside of the cockpit seating, Stb. side. The hose actually runs in the channel between the seating lid and the vertical portion of the cockpit. The hose then runs aft to the transom through hull, staying as high as possible to keep water from accidentally entering from the transom.
Now for the tricky part that I did not understand at first and apparently still do not. There are two 1/2 inch(???size) ports for circulating water out of the engine manifold or heat exchanger, (not sure sitting here at home) to a "anti siphon" system and then back to the manifold. One hose runs down under the sole, aft to the back side of the galley bulkhead. It runs upward as high as possible above the little door behind the stairs. At this peak there is a three way "T." The 1/2 " hose then runs back to the other of the two 1/2 " ports. The third port coming out of the tee is reduced for a small 1/4 " (size??) hose that runs down to the back end of the Vetus. I needed to tap a nipple into the Vetus to accommodate this hose. The purpose of this is to stop water from siphoning in back from the exhaust water into the manifold and into the cylinders. That being said I now am confused as to what it is truly doing. Here is my thinking and I MAY get it right and I could be WRONG!
If nothing is broken ( ie blown head gasket ) fresh water in the heat exchanger system has no way of leaking into a cylinder. Thus there is no need for an anti siphon sytem for fresh water.
On the exhaust side, raw cooling water from the heat echanger is mixed at some point with the engine exhaust to be blown overboard. I think this point is in the "riser" at the back end of the manifold. This junction point is where salt water can flow back through the path where exhaust from the cylinders comes from. So, somehow these two 1/2" hoses connect with the salt water chamber in the heat exchanger to stop the siphoning of raw water into the cylinders. I know this is not clear, perhaps you can figure it out and let me know.

Anyway, I hope this helps.
Please feel free to e-mail me back for more questions. I will be home more now. I will try to post a story of my dismasting soon. Suffice it to say check your chain plates for cracks. My forestay chainplate broke, metal fatigue. It cracked on the inside bend as the plate bends allong the bow and back to aim at the top of the mast. I think these forward chain plates are minimaly built and should be replaced on all Ericsons.
Cheers,
Bill
 
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