What would you replace a MD7A with

[PhillM]

My old MD7A has come to the end of its life. I was going to put in a recon MD7A that a local engineer had but this looks like it may fall through.

Boat is 25' wooden, about 3ton. Don't need anything fancy, just to get up the river and back.

What does the forum think would be the best NEW replacement.

Oh, and money is tight.

Thanks,
Phill

 

[Tranona]

You won't be able to avoid spending as you will have to replace the ntire drive train - engine, box, prop. Almost certainly you will find the shaft and seal/bearings, exhaust system, controls and electrics will also need work. You are looking at material cost around £5500 less what you can sell your existing bits for. You will need to do something with the engine bearers but details will depend on the engine you use.

The obvious contenders are Beta or Nanni 14 or possible 16, Vetus M2, Yanmar 15, Volvo D1. The first two are probably the most popular for re-engine applications. Which you choose will depend on details of how they fit in your boat, particularly service points, cost of package and probably colour. Technically, although there are detail differences, functionally there is very little difference - and when you get the full quotes, not a big price spread!

 

[PhillM]

You won't be able to avoid spending as you will have to replace the ntire drive train - engine, box, prop. Almost certainly you will find the shaft and seal/bearings, exhaust system, controls and electrics will also need work. You are looking at material cost around £5500 less what you can sell your existing bits for. You will need to do something with the engine bearers but details will depend on the engine you use.

The obvious contenders are Beta or Nanni 14 or possible 16, Vetus M2, Yanmar 15, Volvo D1. The first two are probably the most popular for re-engine applications. Which you choose will depend on details of how they fit in your boat, particularly service points, cost of package and probably colour. Technically, although there are detail differences, functionally there is very little difference - and when you get the full quotes, not a big price spread!

Thanks, I was assuming that I wouldn't see much change from £7-8K but I have to be honest and say that I have no idea how to select a new engine. What is most concerning is that it looks like I will have to make a quick decision if I am to get it ordered, installed and commissioned in time for next season. I doubt that many engines are off the shelf and engineers seem booked months ahead.

I dont care about colour! I just want it to propel the boat at up to hull speed and with bullet proof reliability.

Last year I had a new fuel tank, prop and cutlass bearings. I'm not convinced that prop is correct because we get a high pull to starboard under power.

Anyone out there done a similar job in the last couple of years and can give reasons why they chose a particular engine?

 

[sailorman]

Thanks, I was assuming that I wouldn't see much change from £7-8K but I have to be honest and say that I have no idea how to select a new engine. What is most concerning is that it looks like I will have to make a quick decision if I am to get it ordered, installed and commissioned in time for next season. I doubt that many engines are off the shelf and engineers seem booked months ahead.

I dont care about colour! I just want it to propel the boat at up to hull speed and with bullet proof reliability.

Last year I had a new fuel tank, prop and cutlass bearings. I'm not convinced that prop is correct because we get a high pull to starboard under power.

Anyone out there done a similar job in the last couple of years and can give reasons why they chose a particular engine?

I have heard that Nanni are better marinised.
mine has no anodes & doesnt over heat
Beta make bearers to suit your existing beds & sell anodes
but i am not biased of course

 

[Tranona]

The prop on new engines runs the other way. Installed professionally your £7k is about right depending on how much work is involved with modifying the bearers, although this can be minimized if you buy a Beta or probably a Nanni because they will be able to provide brackets to fit in the same way as the Volvo.

Not difficult to buy, nor will you have any problem getting a new engine, although getting it fitted might mean booking the fitter in advance. You can either go to the manufacturer direct or through an agent - you will get a good deal either way. DIY is not as difficult as it might seem. Certainly taking the old one out is a DIY job. Worth selling your existing engine while it is still running in the boat - the buyer may help you take it out.

Your main constraint on your boat is likely to be the size of prop you can swing so it is usual to fix that first and then work back to what engine and reduction box will drive the prop to achieve your maximum speed. Do not be tempted to overpower. You will almost certainly find the 14/15hp engine more than adequate.

There are plenty of dealers along the south coast who will do supply/fit packages for you. give them details of your boat and get some quotes.

BTW colour is important as must go with either the hull colour, or if this is white, with the upholstery or curtains!

 

[webcraft]

Thanks, I was assuming that I wouldn't see much change from £7-8K ?

We fitted a Beta with gearbox, new shaft, folding prop and all the trimmings and spent well under £5k - but I did all the work myself. It's not rocket science.

- W

 

[LittleSister]

Many engine suppliers will offer a 'boat show' discount (typically around 15% IIRC) around the time of boat shows (whether you are at the show or not, I believe). Whether you can get such a discount at other times of year (possibly called something else!), I don't know.

We are very happy with our Beta, but as others have said, there is probably little between varrious makes in reliability and price. Having a well regarded local agent to do the installation (if not DIY), mountings that suit your existing engine bearers, and a gearbox that suits your prop size needs, are key issues.

Consider also the quality and availability of after-market support and advice. We have had great support and very responsive service from Beta, and know other boat owners who have had pretty poor service from one of their competitors.

 

[fishermantwo]

My yacht came with a rebuilt MD7a. Locally they sell for $2250. These are rebuilt engines probably from people who have undated to the modern engines. It runs well and is just as smooth and quiet as the Kubota 3 cylinder generating plant my fishing vessel had. Thinking about converting to fresh water cooling just to get another 20 years out of it.

 

[Lodesman77]

I have just rebuilt my MD7A and now hope to get a few more years out of it; but going through the options prior to biting the bullet I had decided the new engine option would be the beta 16. I had decided it was preferable to the 14 due to the greater displacement/better torque curve. As others have pointed out the equivalent Nanni is always worth looking at as it's the same Kubota base engine, but slightly differently marinised - so see what packages are available and which would fit your installation best.
As you'll have to change all the sterngear/prop as well it might be a good idea to consider which new prop would suit you best and factor that in first...

.

 

[PhillM]

Thanks all for the advice.

With the restoration I have teken the view that if we do a job we do it properly and address all problems in that area. The idea is that once done, it wont need to be re-done. So, time to dig deep for a budget to do the necessary (sigh)

With that in mind, what should I be specfying. So far the list is:

Boat is wooden 25' weighs in at around 3tons. Current engine delivers only 3kn through the water but I would like to be able to get closer to 5 or 6 kn if it is affordable.

New engine
New gearbox
new shaft, prop, stuffing box(?) and cutlas bearing
New exhaust system (current elbow is ver corroded)
New electrical system
New throttle and control panel

Altenator for battery charging (should that be similar to the 60a that I have or should that be uprated?)

Should I be asking about...

Mechnical / engine driven bilge pump?

Hot water (we only have one sink and one fresh water tap at present)

Anything else?

Any Gotch's I should be loking out for?

Timeline is to make a decision by Christmas and order for install asap. Ideally, before end of February.

 

[V1701]

Another Beta 14 here, love it - very reliable & economical, uses about a litre an hour with a Gori folding prop on a Vega which will be about 2.5 tons. There's a drain plug in the sump so easy oil changes. Gets quite a lot of fan belt dust with the standard belt but you can fit different pulleys & have I think it's a triple vee belt which does away with this...

 

[scottie]

It is worth checking which if any engines will fit on existing bearers some manufacturers such as Beta make a sales point of supplying mounting to fit existing units
Shaft and exhaust may be reusable propeller is essential to match new unit if old prop is near to size thats a lucky
All will come with fresh water cooling which will allow hot water but this does not need to be utilised from scratch but would be a great selling benefit to help justify expense if you do go down this route you will require calorifier so may be worth looking at fitting whilst doing other work
Biggest change is electrical output will be much improved without necessarily requiring much alteration.
It's easy to just do whilst I'm at it items but may not be essential and not necessarily value adding to boat.
The actual engine cost percentage could vary from 90% up to 50% of total cost so the fitting & extra costs are the ones where you can make savings.

 

[macd]

Another Beta 14 here, love it - very reliable & economical, uses about a litre an hour with a Gori folding prop on a Vega which will be about 2.5 tons. There's a drain plug in the sump so easy oil changes. Gets quite a lot of fan belt dust with the standard belt but you can fit different pulleys & have I think it's a triple vee belt which does away with this...

Not a triple vee but a polyvee (sometimes called a serpentine belt). The Beta 14 through to the 25 now come as standard with a polyvee, which is longitudinally ribbed, just like the fan belt in your car (unless it's a classic ). Mine (on a Beta 28) did 2000 hours without adjustment and was changed just to be on the safe side: it looked unworn. Why any manufacturer persists with V-belts is beyond me.

 

[Tranona]

Thanks all for the advice.

With the restoration I have teken the view that if we do a job we do it properly and address all problems in that area. The idea is that once done, it wont need to be re-done. So, time to dig deep for a budget to do the necessary (sigh)

With that in mind, what should I be specfying. So far the list is:

Boat is wooden 25' weighs in at around 3tons. Current engine delivers only 3kn through the water but I would like to be able to get closer to 5 or 6 kn if it is affordable.

New engine
New gearbox
new shaft, prop, stuffing box(?) and cutlas bearing
New exhaust system (current elbow is ver corroded)
New electrical system
New throttle and control panel

Altenator for battery charging (should that be similar to the 60a that I have or should that be uprated?)

Should I be asking about...

Mechnical / engine driven bilge pump?

Hot water (we only have one sink and one fresh water tap at present)

Anything else?

Any Gotch's I should be loking out for?

Timeline is to make a decision by Christmas and order for install asap. Ideally, before end of February.

A Nanni/Beta 14 will easily get hull speed on your boat. As I suggested earlier you need to see what size prop you can accommodate in the aperture. Ideally you need 15% diameter clearance - so around 2" on a 15" prop, which will need the 2.6:1 reduction. Smaller prop will probably use the 2:1. You need to check this with the supplier and get their recommendation for prop size. The engines are freshwater cooled and have the fittings to take a supply off to a calorifier for hot water. Biggest problem on a small boat is finding space to fit the calorifier. You also need to consider a water strainer for the seawater intake and an anti syphon valve. The exhaust needs a water trap and a swan neck just before the outlet.

The 14 comes with a 55A alternator which is more than enough for normal use. Best to fit a small engine start battery and as big domestic as you can fit with split charging. Various different ways of doing this, I use a BEP Marine switch cluster with VSR.

Your needs are no different from other re-engine job so any of the specialist suppliers will be able to put together a package for you.

 

[PhillM]

I have decided to start shopping around on Monday. Anyone got any recomendations - I'm based at Swanwick and would like somone quite local.

I have heard a few names and had a couple of convesations today, so I'm looking for recomendations (or warnings) based on personal experence. PM me if you would rather keep your comments private.

Thanks again,

Phill

p.s Re boat value, I dont think my boat has one to anyone other than me. I've been to Decans a couple of times today (well over £250 just on paint and "stuff") and was quite shocked at how cheap the 2nd hand boats are. It looks like I could buy a replacement boat with a newer engine, cheaper than a fitting a new engine!

 

[robmcg]

Keep costs down a bit :-

http://www.apolloduck.com/feature.phtml?id=166097

No connection. Just a possibility

 

[Tranona]

not sure what that is - but not a regular Yanmar marine engine. Looks like the sea water pump and heat exchanger are DIY jobs.

 

[fishermantwo]

5 or 6 knots with a 25 foot yacht is going to need a fair amount of horsepower and a decent 3 blade fixed prop. The Md 7b you have will do that with a decent sized 3 blader in calm water but before you over capitalise on this vessel it might pay to decide what your trying to achieve. Is it a motor boat or a yacht?

 

[doug748]

.....

With that in mind, what should I be specfying. So far the list is:......

New engine
New gearbox
new shaft, prop, stuffing box(?) and cutlas bearing
New exhaust system (current elbow is ver corroded)
New electrical system
New throttle and control panel

Altenator for battery charging (should that be similar to the 60a that I have or should that be uprated?)

Should I be asking about...

Mechnical / engine driven bilge pump?

Hot water (we only have one sink and one fresh water tap at present)

Anything else?

Any Gotch's I should be loking out for?
......

I have a Beta.

The standard alternator is fine for me, if you go for larger you will probably want to increase battery capacity to match.

I did not bother with hot water, you can always put the kettle on. It saves all the extra pipes, and it is often tricky to find the room for the tank on a small boat. You could always add one later. If there are ladies on the crew manifest, they may have other opinions.

A high level exhaust is normally extra and is worth thinking about if you have the room. Particularly handy if you have a limited fall from the exhaust injection bend. It helps prevent seawater being forced up the spout and into the engine.

Look out. You are very likely to have to increase the diameter of your raw water intake and pipework (new seacock and, probably, strainer as well). Ditto the pipework for the fuel supply and leak off (you will probaly want to update your primary filter at the same time)

Special engine feet are often not required on a wooden boat, as it is easy and coachbolt new flat plates onto the existing engine bed, using packing as required. Esp if the new engine is narrower than the existing.

I found the short cruise spares kit not particularly good value - better to source a spares kit to your own requirements. If you do buy a Beta, never buy Johnson impellors which have proved poor in service, I always fit the Jabsco alternative. Anodes can be got for a few pounds each. It must be said that spares from Beta are generally priced fairly.

 

[LittleSister]

We have a Beta 14 (actually 13.5hp) in our 23' long-keeler, 2.4 tons design displacement (i.e probably more really). This engine is more than adequate in power, and I'm sure a 10hp would have been enough.

It was fitted by a Beta agent somehwhere in the East Solent for the previous owner, who has done a nice job. I will try to find the name of the agent for you.

We are very happy with both the engine, and the support from Beta - very knowledgeable and helpful, and spares delivered next day.

I would guess the 14 would be fine for your boat, and the Beta 16 would be more than adequate but not over the top.

As others have said there is little difference between a Beta and a Nanni. Nanni's range is not so extensive in the smaller sizes, and IIRC there is a 10 and 14, but not a Nanni 16 in the current range.