Nanni engine install to replace a perkins 4107

[nauticalnomad]

I have just ordered a Brand new nanni 43HP engine with Hydraulic propulsion to replace my aged 4107. I have not made the transaction as yet but...
Has anyone else made this choice or any insight into it.
power loss etc compared between shaft and hydraulics etc?
prop sizing?
pros and cons?
install problems?

I have now a 4107 running through a vee drive and back out underneath the engine, I am replacing it with a 43hp engine through a hydraulic drive?
Is the powerloss from the 4107 to the vee drive going to be the same as the powerloss from the 4.43HD (43HP) to the Hydraulic driven propellor?

 

[Tranona]

Think I would avoid a hydraulic drive if at all possible. Peachment can tell you what the losses might be.

If length is a problem (usually is when a V drive has been used) and the conventional drive is still too long, Vdrive gearboxes are still available - Beta, for example offer the ZF, although it is more expensive than a straight drive, but may be comparable with hydraulic.

As to props, you will have to match the size and type to your final installation, taking into account the data on your boat (particularly LWL and displacement) and shaft speed (function of engine speed and reduction ratio). You may well have constraints from clearance limiting diameter and of course there are many different types of props on the market. Again Peachment will be able to recommend sizes, as will other prop suppliers based on the information you give them.

BTW sounds like you have a Nic 35 - many have already been re-engined so it may be worth finding owners who have already done it.

 

[nauticalnomad]

Think I would avoid a hydraulic drive if at all possible. Peachment can tell you what the losses might be.

If length is a problem (usually is when a V drive has been used) and the conventional drive is still too long, Vdrive gearboxes are still available - Beta, for example offer the ZF, although it is more expensive than a straight drive, but may be comparable with hydraulic.

As to props, you will have to match the size and type to your final installation, taking into account the data on your boat (particularly LWL and displacement) and shaft speed (function of engine speed and reduction ratio). You may well have constraints from clearance limiting diameter and of course there are many different types of props on the market. Again Peachment will be able to recommend sizes, as will other prop suppliers based on the information you give them.

BTW sounds like you have a Nic 35 - many have already been re-engined so it may be worth finding owners who have already done it.

The boats a 43ft Angus primrose designed admirals cup racer from the 60's, the prop recommened for the nanni is (18 x 13), I cannot swing it anyway, The current prop is like a bow tie.
I am not fussed by the Hydraulics change, I am trying to work out whether the loss of power between then hydraulics and nanni engine is the same as the loss between the perkins and the vee drive etc?

 

[sailorman]

Have you tried the MoBo section yet Scott

 

[nauticalnomad]

Have you tried the MoBo section yet Scott

Not yet?
I thought id posted in all sections here?
Is the Mobo section the same YBW website etc?

 

[sailorman]

Not yet?
I thought id posted in all sections here?
Is the Mobo section the same YBW website etc?

double posting is regarded as being very Naughty indeed

 

[nauticalnomad]

double posting is regarded as being very Naughty indeed

I thought posting once made it available to everyone?

 

[sailorman]

I thought posting once made it available to everyone?

already on ECF as well

 

[scottie]

The hydraulic drive is not very efficient but was one solution of flat bottomed boats as it does allow the engine to be located away from the propshaft it could even go under the table.
.I have a recollection that in some cases the engine was moved for racing but it was a while back.
The saildrive was considered a better solution .
I would get something in writing rgarding the performance but you may be limited by propeller diameter.

 

[Tranona]

The boats a 43ft Angus primrose designed admirals cup racer from the 60's, the prop recommened for the nanni is (18 x 13), I cannot swing it anyway, The current prop is like a bow tie.
I am not fussed by the Hydraulics change, I am trying to work out whether the loss of power between then hydraulics and nanni engine is the same as the loss between the perkins and the vee drive etc?

Why do you think you need a hydraulic drive? This is usually used on an installation where the layout dictates that the engine needs to be in a different place from immediately in line with the shaft. Losses in power through a conventional gearbox (or a V drive) are small, but greater with hydraulics (not a hydraulic gearbox but a pump and motor). The manufacturer will be able to tell you what the loss is.

When re-engining, the only fixed point is the existing shaft and stern gear so you start with that and see what fits. As you have discovered prop clearance is often a constraint so you may need to consider a different gearbox ratio to use a smaller diameter prop than is ideal. It is best to forget altogether what you have now and work out (or have somebody do it for you) the best compromise given the constraints of where the shaft is now. You will have to replace just about everything except for the stern tube anyway. As already suggested as an alternative you might be better off junking the whole lot and fitting a saildrive which is much more compact fore and aft and allows a much wider range of props, particularly if you fit a Volvo or Yanmar.

 

[nauticalnomad]

Why do you think you need a hydraulic drive? This is usually used on an installation where the layout dictates that the engine needs to be in a different place from immediately in line with the shaft. Losses in power through a conventional gearbox (or a V drive) are small, but greater with hydraulics (not a hydraulic gearbox but a pump and motor). The manufacturer will be able to tell you what the loss is.

When re-engining, the only fixed point is the existing shaft and stern gear so you start with that and see what fits. As you have discovered prop clearance is often a constraint so you may need to consider a different gearbox ratio to use a smaller diameter prop than is ideal. It is best to forget altogether what you have now and work out (or have somebody do it for you) the best compromise given the constraints of where the shaft is now. You will have to replace just about everything except for the stern tube anyway. As already suggested as an alternative you might be better off junking the whole lot and fitting a saildrive which is much more compact fore and aft and allows a much wider range of props, particularly if you fit a Volvo or Yanmar.

The engine space is already in a good area and is accesible completely it sits high, so i am wanting to put the new engine back where the perkins is, The gearbox goes by prop to a vee drive then back out etc, A vee drive is 2500 pounds, the gearbox is what ever a gearbox is worth, 1000-2000 pounds.

A sail drive is another hole in the hull which i didnt want to do!
Im not planning on motor sailing, etc

I have also discovered i can get an inline hydraulic 10kva genset that works off the same system without having to install a generator to the boat,
which sounds like a good idea,