Time to re-power

Well - It seems my 32 year old old Volvo MD17 has come to the end of her run time.
Over the last few months she's been running a bit hot if I pushed it over 2200 rpm. Then a week ago, I noticed signs of water in the oil. I changed the oil, and tried to re-start the old girl. No luck. I bled the lines, changed the filters, but no fuel getting up to the injectors; it appears a faulty injection pump is the culprit.

Hmmmm... Injector pump + head gaskets? + liners? + ????? = $$$$$$$$; and I would still have a 32 year old raw water cooled engine.

I stopped here. Rather than rebuilding the injection pump, then chasing the source of water in the oil; I decided to cut my losses and re-power. Getting parts for these old Volvo's is becoming more difficult and expensive all the time. I could get part way through a rebuild and find the required part is no longer available.

So - I'm waiting on a few replies, but I'm leaning towards a 43hp Beta (Kubota). They are non turbo, fairly low (2800) rpm, and have the engine layout that matches my limited access.
It gives me a few extra hp to play with, to drive a bigger or 2nd alternator, and possibly a future refrigeration pump.

Another Sydney company, WM Diesel also marinizes the Kubota.

I'm still working out what gearbox setup to go for. My current Volvo MS2 has a 7 degree downward offset. I'm checking to see if I can get a similar gearbox which can be driven either way allowing me to re-use my existing newish LH prop.

Oh - the joys of boat ownership.

Heavy on the power but I've heard nothing but good about Beta.
In the US parts can be a problem.
Vetus may be a good bet especially down there.
What is your displacement?

You might also check the Nanni 4.40. It's the same 2 litre Kubota base that the Beta 43 uses. I think the smaller Vetus engines are Mitsubishi base, and they are rated at 3000 RPM.

Modern engines (IMO) are all so good that choice should hinge on the dealers rep. Is he someone you can deal with and rely on?

A few years back here in Washington State the delivered Nanni was significantly less money than the same Beta. That may or may not still be the case.

Eric - she's about 7 tonnes. In theory, a 25-30 hp would be enough but a few extra hp come in handy pushing into a big headwind. The present volvo had struggled at times but I doubt if she producing her full 36hp anymore.

TAD wrote;
"Vetus engines are Mitsubishi base, and they are rated at 3000 RPM"
Yes my Klassen has a more industrial look and basic paint job. I bought it because of all the options available, the steel exhaust manifold, Klassen's rep, and it was offered w the power I deemed necessary. I really wanted a Klassen/Isuzu but it was 54hp.
The Vetus line includes the Mitsubishi engine I have and a shorter stroke version of 4hp less. The 42hp Vetus is the same block as mine. I loved the beautiful yellow paint on the Vetus and it was tidy and compact compared to my Klassen. One option I picked didn't work well .. the remote oil filter set up. I took it off reciently.

I have to concur with Tad. The Nanni is what I'd repower with if something ever happened to my Yanmar. It's simple, brutish, and common in reliability with the whole line of sub-100 HP Kabota/Nanni's.

Yes - the Nanni does look like a good option. Thanks for the tip. I didn't realize they were also Kubota based. They are slightly lower profile than the corresponding Beta model. That's a plus; In my "engine room" every inch counts.

Another question I need to sort out is the gearbox. The old Volvo engine is mounted at a 4 degree downward slope with the MS2 gearbox angled at 7 degrees downward for a prop shaft angle of 11 degrees.
Ideally I'd like a gearbox that will freewheel without any problems, and is bi-directional so i can perhaps keep my recently purchased prop. Also, the gearbox angle downward needs to be 7-11 degrees to keep the engine as level as possible.

There will be a range of angles for propeller shafts for every engine and probably easy to find. As I recal Yanmar offers packages w gear boxs at numerous angles.

I'm kind of against aluminum cased gear boxs. I had one on a small Yanmar. It was a Kansaki and was very noisy. I went to great efforts to reduce the noise.

manyboats said:

There will be a range of angles for propeller shafts for every engine and probably easy to find. As I recal Yanmar offers packages w gear boxs at numerous angles.

I'm kind of against aluminum cased gear boxs. I had one on a small Yanmar. It was a Kansaki and was very noisy. I went to great efforts to reduce the noise.

Click to expand...

As Eric mentioned, Yanmar has a diesel that you might look at. The 3JH5E is 38.5HP at 3,000RPM (35HP at 2,900RPM continuous). It is available with a Kanzaki KM35A gearbox which has a 7° down-angle, but is RH in forward gear. It now includes a standard 125A alternator.

I have not found the KM3 or KM35 gearboxes to be that noisy, well, at least they cannot be heard over the engine noise.

I'm not sure about the availability of Yanmar in Australia, but they are often specified as OEM power in the rest of the world.

I have also heard great things about Beta.

Good luck with your project

Selecting an engine with more advertised HP will be fine if you dont go overboard.

Remember Volvo rated the single cylinder version at 15 hp, the 2 cyl at 25 hp and the 3 at 35 hp.

So when run to 2500rpm you probably already have 45 hp from the old Volvo.

With no fresh water cooling lasting as long as it is is remarkable!!

For the same smoothness, quiet and lack of vibration stick with another 3 cyl engine.of about 100Ci in size.

Be sure to check front belt allowed loading for the new engine

IF you have mechanical refrigeration , big alternators or Hyd pumps or an engine driven bilge/fire pump.

Try and get one without a computer...

If you want a new gear I think you'll end up with a ZF Hurth 15MA with 8 degree angle.

Xsbank,
I don't think there is any engines in this power class (40hp) that have any of that stuff. Mine is basically the same as the Perkins it replaced but for thin wall castings and probably quite a few other things I'm unaware of. David probably knows about that.

I agree Larry. The 40hp 3 cyl Yanmar would be fine. I saw no point in spending the extra money for what I thought was basically nothing. In the small engines Yanmar is a bit like Cummins and Deer. Those high end engines may be a tad better but I think it's fly stuff if at all. My Mitsubishi cost less than 6K and the Yanmar was $10000 as I recall. The Yanmar that I did have in are vinous boat was excellent though. Noisy compared to my Mit probably because it didn't have a pre-combustion chamber but it didn't require heaters/glow plugs for starting. I considered that a negative at the time but now I prefer the pre chambers and glow plugs ..... and the quieter engine. The glow plugs are super simple, even to replace and provide instant starting always.

The smalles 4cyl I know of is the Vetus that's a de-stroked version of my mitsu/Klassen.

Picking an engine should be pretty straightforward. I am partial to 3cyl in that hp range, as they lack the 2nd order vibration that a four has, if the four does not have balance shafts. The 3 has a 1st order "waddle" but I find it less objectionable than the four's "buzz" at higher revs. But this is a minor issue, neither would be a deal breaker.

Whether a Kubota, Mitsubishi, Shibaura, Yanmar- all first rate machines. Some marinized better than others, but as long as you buy an established name with company supported in your area, should be ok.

Now to the gear. That is going to be an issue. The gears in this hp class, ZF 15, 25, Kanzaki, are all mechanical shift. Mostly meant for sail aux engines. They do work but most make a heck of a clank when engaging, and rattle badly at low revs. They also wear faster, ultimately not wanting to engage.

I have set up three planing skiffs using ex-generator engines- and the gears gave me the most headache. Hate the bang shift and rattle. One gear ultimately pooped.

Much preferred is a hydraulic shift with multi-plate clutches such as the antique but very serviceable Velvet Drive... Notice the significance of it's name!! ZF also makes smallish hydraulic gears, but I have not kept up with their offerings.

My experience is that the hydraulic offerings are rated for much more hp than the 50hp class, and so in this app would tend to be overkill. Also the hyd will have more parasitic losses than the mech gears.

But if you can find a suitable hyd gear, that would be well worth it.

Thanks for the input.
I'm taking it all in without making any hard decisions yet.

So far Nanni have been the quickest to reply & ask all the right questions.

The 4 cylinder 38hp Nanni weighs just over half what the 3 acyl 36hp Volvo weighs. 152 kg vs 281 kg for engine & gearbox (and the volvo didn't even have a heat exchanger).
I might have to look at moving the engine back slightly to keep the weight trimmed properly.

Still looking at gearbox options. There is a lot to consider regarding choice of transmission, engine mount positions, angles etc.

Ski,
Coupling an engine of less than 40hp to a Velvet Drive can be better matched if a smaller gear is installed in the oil pump. Mike at Harbor Marine in Everett WA rebuilt my BWVD especially for my small engine. The oil pump gear is about 1/4 to 1/3 as wide as usual greatly reducing the power required to power the hydraulic clutches. Also he installed much softer clutch discs for smoother shifting. You've heard the expression "like butter" .... my TX is very much so.

Aus Can,
The engine in my Willard is about amidships so the much lighter Mitsu didn't disturb CG but the heavy BW gear helped as ballast. The BW was also original equipment. Do you have room for a BW? It's not hard to match them up to most engines.

Ski,
Say whatever about 3 V/S 4 cyl IMO it holds less water than 3 V/S 4 blade props. Old 4cyl gasonine cars did indeed buzz. My 4cyl boat does not. I've had both a 4 and a 3 and say it's a toss up. But it's a bit like saying an 6cyl is smoother than a 8. Never ever convince me of that.

Also I think FFs suggestion that focus on an engine of about 100 cu in is excellent. Mine is 107 cu in and I believe my boat to be very slightly overpowered. That's at 5hp per ton and for a real FD hull 4hp is about minimum. There was a boat featured in PMM quite a few years ago that had a Gardner straight eight engine of 135hp and the numbers came in for that one at 2hp per ton. That would be equivalent to about 18hp in my boat. I wouldn't consider that enough but that's the lowest power loading I've ever seen. The boat was wood and about 70' long w a typical beam of a trawler. There were (to my recollection) not any obvious signs of light displacement. She looked a lot like the PNW boat Griffin.
So I think FFs Mark of 100 cu in is spot on.

AusCan said:

...

So far Nanni have been the quickest to reply & ask all the right questions...

Click to expand...

I think Nanni use (or used) Renault engines, no bad thing.
Someone asked about Yanmar. They are well established in Australia and advertise in "Afloat" mag. including about repowering. The guys (2 man marine mechanic business at Balmain) who help with my Lehmans are Yanmar dealers.

M/B- Nice to know about that modified BWVD. That's an option, for sure, and with a well selected planetary, can get to use the LH wheel also. Extra weight from the gear not an issue as OP was concerned a bit about going too light in the motor dept.

With 30 years+ on the Volvo , the fuel burn should be well established.

Cold (sea water cooled) engines are not efficient so perhaps 15 hp costs 1 GPH.

Our MD 3B in a 17,000 MS (same engine just older) burns 3/4 GPH for almost 5000 hours. 6.5Kcruise with 28ft LWL. about 12 -13 HP at best.

It does have mechanical refrigeration and 2 big alts , but that does not change the burn over a tank (24gal) of fuel.

Your fuel burn at normal cruise will help in deciding engine size .

I would oversize ant Hurth tranny by 2 sizes for reliability.

Happily parts to rebuild them is cheaper than others , but bigger may save the hassle.

AusCan, why not consider another Volvo?

CPseudonym said:

AusCan, why not consider another Volvo?

Click to expand...

I haven't completely discounted a new Perkins based Volvo D2-40F, but my initial inquiries suggest the cost is significantly higher than some of the others.

Also I've heard some bad reports about their electronic "black box" which manages starting, glow plugs, engine hours etc.

I think the Volvo D1 and D2 series are simply Shibaura engines. Perkins also marinized these. See little point going through so many layers of Euro companies to get a basic Japanese mini-tractor engine.

Have had Kubotas in Peggy-Anne for 15 years. Done 5000hrs no big probs. Economical to run and parts readily available. Hope to get another 5000 at least. Bloody great little motors

After researching & measuring & getting prices I'm now leaning towards a Vetus M4.45 (42hp Mitsubishi based)
My choices were limited due to the driveshaft position being low in a narrow bilge. The old Volvo had rear engine mounts higher than the front engine mounts. All new engines have all 4 mounts on the same plane.

So - The Vetus will fit nicely with Hurth ZF-25A gearbox. This gearbox has a higher vertical offset than most, and a 8 degree down angle which lines things up perfectly. A bonus with the hydraulic transmission is that it can be run either way, so I don't have to change out my LH prop.

Was a busy weekend - I pulled the old Volvo out, along with both fuel tanks. I now have an engine room! Begun the clean up of 32 years worth of grime.

Fitted my "test engine"; a wooden Vetus mock-up, which confirmed my angles measurements. Nice quiet engine, but not much power.

It is common to need to fab custom brackets for mounts. Rare for the factory stuff to fit unless building a new boat.

Don't skimp on motor mounts. I like Metalastic mounts for small diesels with low cylinder count. The soft mounts keep idle vibes from getting into boat structure.

The other "fun" comparison is to plot the HP/torque curves of each considered engine on MS Excel to compare directly. Unfortunately I plotted 50-60hp and 70-75hp groupings. Nothing smaller.

If you like drop me a pm with your email and I can send you mine to use as a template.

AusCan,
That's great. Now there's someone w the same engine as mine. Not that there's any real meaning to that but I like anyway.
Love the Vetus yellow. My Mitsu came in an industrial flat black and looked used from the start.
Something I can recomend from my own experience is PolyFlex engine mounts. They are plastic .. as I recall. It seemed to me that reduction in vibration would be more likely if the material used actually absorbed some movement and energy. Rubber tends to return almost 100% .. that's why a rubber ball bounces. Based on that thinking I bought PolyFlex mounts for Willy and am still happy w that decision. I had my aft mounts moved aft to the BW gear to more evenly distribute the total weight of the package. Engines w more than two cylinders don't pitch much but move radially a lot. Mounts at the same height is also a benifit IMO.
The oil filters are very small and I prefered the vertical oreintation so I went w a remotely mounted filter that was considerably larger. I don't recomend that as I was plagued w oil leakage. Just reciently I removed the remote plumbing and mounted the small filter where Mitsu put it. I was accustomed to changing oil often and the filter every third oil change but now w the smaller filter will change the filter every oil change.
FYI .. I start after 6 to 10 seconds of glow plug operation depending how cold the engine is. Have not replaced any glow plugs in almost 10 years. I'd recomend the Orange long life AF for you because of your aluminum exhaust manifold. I use 30W Delo oil and am wondering what Vetus recommends. I have a manual reciprocating oil pump/extractor connected by a hose attached to the drain plug provided by my marineizer .. Klassen in BC Canada.

Eric,
Vetus seems to do a good job on the Mitsubishi conversion. On this model (M4.45) it has a cast aluminium coolant tank on top of the engine. Besides assisting with cooling, it also acts as a sound shield, reducing engine noise level by 5 dB.
They come with a 5 year warranty on the engine, (3 years on the heat exchanger) and the price was about 35% less than a similar sized Beta fitted out with similar options. They also allow self servicing with non-Vetus parts without affecting the warranty.
All up, it looks like it will be a good package .

REPOWER.The "KOKANEE"

Seems the choice are easy.

The Nanni 40 HP. 2.0 litre engine I agree with you will be the rigth engine for your Vessel, - also what you leaned to begin with.

Th Nanni people are rigth at your doorstep in Port Adelaide, Becker Industrie.

This Kubota of the Super 03 series are known to be a beefy engine, good stamina, weigth: 256 kg. a hefti torque curve already from 1200 rpm.
up to 2100 rpm. some 14 kgm.- proves it.

As you said, liked to have more HP. for exstra equipment. Mark: the 38 HP.Nanni are only 1.500 cc. some max.torque :8.3 kgm.


The gear are often more to worry about, than engine, so awoid this, but take a bigger than the standard, if TMC 60 are standard then go for a a TMC 260.
Or better still, a ZF. 25 hydraulic, alt. ZF.25 man.operated.
Both ZF25 gears can deliver a 2.72:1 reduction ratio.

Since the prop. are the only media to tranfer Power to Water, a big dia. slow turning prop. are of importance, for a heavy vessel as your KOKANEE, to push tru Water, at 7.0 knot max. speed 7.3 kts.
7.0 knot at 2600 rpm. full power 2800 rpm. told to be 7.3 knot.
Took my time to run a prop.caculator sheet. after a Kuddle 30, hull.
7.ton. displ. 28 feet w.l. red.ratio 2.7:1.
Good luck in Australia, Here in Denmark. Nanni Diesel are higthly rated.

Willard powered the W30 (see avatar) w a 107 cu in engine and over propped it so instead of having 36hp on hand there was only about 33. Even w 33hp the 8 ton W30 is slightly over powered so IMO any deviation from 107 cu in should be down rather than up. Two liters is too big of an engine but the Kubota's are wonderful engines .. no doubt about it.

When I repowered my Willard I was faced w the choice of (after narrowing down) the 107 cu in Mitsubishi or the 113 cu in Isuzu. My favorite was the 54hp Isuzu but was just too much power. Haven't been sorry I choose the 107 Mitsu. It's only about 10% overpowered .. and that seems a very good place to be.
gadenors is the 38hp Nanni a Kabota and is it 1.5 liter? That would seem perfect IMO. A three or a four cyl engine?
AusCan I just checked back and see Kokanee is a ton less than the W30 so even 30hp should be plenty of power. I was afraid to go smaller and understand the situation but in the end for me I could have. If you want to go a bit smaller than the 107 Mitsu they (Mitsubishi) does make a shorter stroke version of the .... I just checked the web site and it looks to not be there. However that's in N America so elsewhere it probably still is. I saw the smaller engine on the Vetus catalog .. but that was about 8 years ago. A stone to possibly overturn though.

The only variable yet unturned yet (I think) is the drag of the hull. If the hull drag is higher than the W30 then perhaps 34hp would be better. The Willard is only average drag for her type .. IMO.

One more comment is that I don't think there's any advantage to a deeper reduction than 2.6-1. Big propellers have their problems and smaller props are more flexible re power loading v/s speed.