Repowering to Diesel - Sailboat

Have a C&C 25 sailboat with a Vire 7 gas inboard. Although tough and simple to repair, the Vire is is a bit weak for this boat and prone to overheating. I would welcome advice on repowering to a small diesel.

Some parameters & background:

The boat is in good shape now and will be kept for a while. I have extensively repaired, rebuilt, and upgraded the boat.

C& C 25 MkI specs:

Displacement: 4138 lbs. (1880 kg.)
L.O.A.: 25' 2" (7.67 m)
L.W.L.: 20' 8" (6.30 m)
Beam: 8' 9" (2.68 m)
Draft: 3' 10" (1.17 m)

I enjoy boat building as much as sailing. I am reasonably proficient with automotive and marine gas engine repair (but a newbie to diesels) . I would prefer to self-install any engine.

Cost is my main concern. I appreciate the utility of inboard power – for tight manoeuvering and in heavy weather. If cost were not a consideration I would install a new diesel inboard without hesitation.

A ca. 10 hp gas outboard is a reluctant second choice. Acquisition cost (relative to inboard diesel ) being its only virtue.

Status quo (living with the Vire and its quirks) cannot be entirely ruled out.

My questions relate to installing a diesel:

1) Besides engine – what additional installation costs would I face (controls, panel, plumbing, cabling, etc)? Very roughly, what might these additional costs add up to on a ca. 10hp diesel installation?

2) How feasible is self-installation with advice (assuming mid-level gas engine and boat building skills)?

3) The Yanmar 1GM10 seems like a candidate. Any opinions on the suitability of this motor for powering my fin-keel sailboat (given its specs):

4) What is the rough (in-the-crate) price of the 1GM10 in Eastern Canada/Northeastern US? Cannot find reliable price data online!

5) Any recommendations on other candidate engines in the 10 hp class (I recognize that specific clearances need to be considered and/or structural mounting modifications made to the boat)?

6) Is it reasonable to assume that NEW is the only feasible option – as good small diesels are not regularly yanked out of boats and put up for sale?

7) Finally - Any buying tips?

Thanking all contributors in advance!

 

The Vire is a pretty simple engine. Overheating is an issue, possibly due to a buildup of scale from raw water cooling.
Other than that problem, there are few engines as easy to repair and little to go wrong to begin with.
I did a rebuild on a Vire 7 a few years ago. It has about two moving parts. I'm no engine rebuilder but the job was a real breeze.
I have also filed the points through a slot in the flywheel and successfully started the engine when it wouldn't start!
My suggestion is to save 5k and keep the Vire. Source a parts engine for any future problems. I'm no lover of two strokes but sailboat auxiliaries don't run enough to make a big deal about things like emissions. More emissions are produced in manufacturing a new diesel engine by far.

 

Peter,

I just Googled <vire 7 inboard engine hp> and got a ton of info I think you'd find helpful.

If you're looking to minimize your costs ("Cost is my main concern"), I don't think you should install a diesel.

Get what you have running well and all should be good. Is your prop correct? Boat bottom "clean"? Engine properly tuned?

If you insist, then I would look at something marginally smaller than 10 Hp. 6 - 8 Hp comes to mind.

You'll get more torque from a deisel than the same Hp gas engine and working it "harder" is better.

You're in for a wack of expenses and I suspect your current set up is not performing at it's best.

-Tom

 

Thanks for your advice Tom

Prop is fine

Bottom is spotless (I sand smooth at the start of every season)

AS for tuning:

The Vire is probably in probably in pretty good shape. I have stripped and entirely rebuilt the engine; replacing all seals, almost all bearings (including the mains); honed the cylinder and replaced the rings (very hard to locate - but found a source); improved cooling flow by tapping a second outlet to the top of the head, replaced points, custom made and isntalled a 316 Stainless injection elbow, improved carburation by installing a new Tillotsen (with a slightly larger wider throat for better mid range power) etc. etc. Periodically check gap, timing and carb jetting. Its well tuned and runs fine!

The raw water plumbing has to be a) carefully routed to prevent drainage under heel; and b) kept spotless (de-scaled). I fully recognize these are important considerations with all engines and cannot be overlooked. However I strongly believe the cooling design on the Vire 7 is weak by design: bib (and hose) diameters are too small and subject to scaling/sediment occlusion; head cooling design can lead to air entrapment; impellor could be a bit larger. In short this engine has zero tolerance for even slightly restricted or partial flow.

There are solutions - One owner has switched to to belt driven higher flow pump; electric pumps are possible; the impellor housing can be machined to a larger diameter and larger impellor used.

FYI - The Vire 7 can theoretically be rebuilt into a Vire 12. The 12 (I believe) is essentially a 7 with with shaved head for higher compression. It also has different carburation.

There are also a few other issues. Noise, smoke and very low generator output.

Upon reflection - I think power and reliability are driving me to look at diesels. Have started single-handed sailing and want a high degree of confidence in my engine.

 

Sine you've mentioned it, I'll add there are several things you can do to improve the power output and cooling issues you have with your current engine. Once you get a good look at used diesel replacements, let alone a new diesel, you'll likely reconsider a rebuild or upgrades to your Vire.

As you've probably found already, the differences between the 12 and the 7 are minor. Some carburetor (new bore and jets) changes, some timing advance and that's about it. There are further improvements that can boost this HP figure further if desired.

As far as cooling, you can boil out the block then install a closed loop for the engine, with raw water for the manifold and exhaust. All of these upgrades would improve the little Vire and make life with it easier to live with.

 

Hi PAR - can you clarify your comment. Do you mean heat exchanger for the head? FYI - Have been thinking about it!

 

Some ideas

Someone from your area posted here a month or two back..had found cheap Yanmars for sale..search for it.

Edit..... here it is:

https://www.surpluscenter.com/sort.asp?catname=engines&byKeyword=yes&search=diesel engine

And you'd have to hook it up to a transmission.

Maybe an air cooled unit? Knew a guy years ago had a Hatz that served him very well for many years.He ran ducting into and out of the engine with a 12V suction fan.

 

Maybe I should have been more clear. Boil (clean) the coolant passages and consider the typical hot rodding options to improve efficiency. Port matching, removing obvious passage restrictions, etc. I'm not all that familiar with this little Westerbeke (I've seen them, but have only limited exsperence with them), but I'll bet the usual suspects of hot rodding tricks can produce cooler running and more torque from this little 2 stroke.

 

Peter, you've made an admirable effort thus far. As PAR says (and he is in the know more than I) if you want to avoid some

serious costs, keep trying. Reed valves, carb jets (bigger) and tuned exhaust are still options to improve performance.

Are there any ways to easily lighten the boat as well? Improve engine room ventilation (cooling), add heat sinks (aluminum). Would you consider keel cooling?

How about selling the boat and buying one more to your liking?

Simply more ideas, not really answering your original questions, sorry.

-Tom

 

There's at least one freeze plug that is easily removed and that gives a window into the cooling jacket. You can at least see whether the block needs cleaning.
Check out the water pump as well. It's located on the rear of the engine. Make sure it's not so worn that it isn't doing its job.
This is probably the simplest engine in the world, which counts for a lot in my book. Not even reed valves, just ported intake. I can walk you through most any rebuild scenario you decide on.
Parts can be atrociously expensive. In '98 I priced a connecting rod at $200.00. The big end bearing (one piece with the rod) was badly scored from rainwater getting into the block. I had the rod bored .007 larger which, using the same size needle bearings, made the crank pin too small by that amount. I had a crank pin made with a .007 larger diameter middle section (the crank on that engine is made up of three pieces). All this saved having to buy a new pin and a new rod as well.
I think you could totally rebuild that engine for under $500.00 if you don't spend too much on OEM parts. For example, points were $45.00 from Vire but matched a common set that sold for $10.00. Gaskets can be homemade. Of course all bearings and seals are standard and available off the shelf almost anywhere.

 

Again, I'm not as familiar with this puppy as Alan, but I do see plenty of places to get more power, improve cooling and it's already reliable. An old trick we used to do was weld on cooling fin extensions, which are just what they sound like, little strips of metal welded onto the edges of fins to make them longer. Some time with a grinder, cleaning up welds and you can increase cooling, though admittedly it's a tedious job of welding mind you.

 

Alan - yes parts can be expensive and increasingly hard to find. However I have been able to utilize non-original parts - Points, rings, impellor, etc. the vire owners' site at gofree.indigo.ie/~vire7/home.htm is great for trading info re: alternative parts.

WestVanHan - Not sure what Princess Auto engine you are refering to. I visit PA once every two months or so - have noticed an air-cooled diesel utility motor on offer. Air cooled and no transmission make this of doubtful value - a likely a false economy.

PAR - Thanks for clarifying.

I wonder if the economics of Vire upgrading really make sense. I could put tens of hours into the Vire for a possibly improved motor. Not to mention parts (e.g. heat exchanger, etc.). Alternatively I could: a) try to sell the Vire - its in good shape - maybe I could get $500 - $900 for it; and b) Take on extra paid work - in lieu of working on the Vire. Putting a) & b) together might account for a significant enough chunk of the diesel's acquisition cost as to make it attractive. I can view any shortfall i.e. Diesel's Price - (a + b) as the cost of a new, more reliable, more powerful engine.

Let's say I sell the Vire for $500 (a= $500) and would have spend a total of 40 hours over winter 2011 on various upgrades, modifications and testing + assorted parts, supplies, machine shop fees etc (b=$2500)

a + b = $3,000

Upgrade cost = New Diesel Cost (installed) - $3,000

We have however drifted from my original questions re: small diesels.

I mentioned the Yanmar 1GM10 -what about the Bukh DV7 and others? Again would appreciate comments on suitability, installation issues, and acquisition/installation cost.

Again thanks for your thoughtful comments to date!

 

If it were my boat I would consider three options.

AS lazy as I am I think I would invest in a really good electric water pump , and simply feed the existing engine all the water it can handle.


Next would be an air cooled Honda , Northern Hydraulics , or similar source,.Under a grand , brand new.

As I'm lazy I would chose the smallest that had electric start.

Next choice would be a visit to the big truck reefer repair folks .

A running diesel , any hp will have electric start and should run about $300.Usually Kubota or Yanmar.

The hookup will be a bit of work, but the savings are worth it., but ONLY if you do far more motoring than the usual 100HR year boater.

FF

 

Once again,google.

All the small diesels are tough and will last for decades with care,You should try your local Yanmar dealer.

Lombardini,Kohler, Beta/westerbeke/universal /Nanni (Kubota based), Onan spring to mind.

I've have friends in and have been to Japan several times,most small sailboats I saw had Robin/Subaru air cooled diesels,don't remember what they did with the exhaust

 

Find a second hand Sabb, Hatz, or Bukh if you want to go Diesel. They are cheap to get and last forever.

If you want to keep your Finnish gem (there was really never a simpler engine in a boat), you may find spare parts in Denmark.
http://www.mmc.dk/

Regards
Richard