Engine advice please!!

Mistybear

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Hi,

I am looking into getting engines for my 40ft wooden boat. Previously she has twin diesal perkins P4s but the previous owner removed them.

I have no idea of where to start looking for replacements - does anyone know what engine/s might make a suitable replacement? Should I stick to Perkins or are there other makes I can consider?

Also don't know what hp I need - she is 17 tonnes. Would one engine suffice or will I definitely need twin engines??

As you can see engines not my strong point so any advice in any form appreciated.....!:)
 
If you'r boat was running twins then you should definutly replace like for like as low speed steering will be all about bursts of power from port and starboard props, ie. the rudder(s) are designd for high speed use and will not have enough area for adaquate controll at low speed.

there is no magic in which make of engine you fit, as long as it goes in the hole. but the amount of power you can deliver is ultimately limited by the size of prop you can swing, which is likely to be limited by the configuration of the stern tube / p bracket / hull.

finnaly, it's very impotant that the engine - gearbox - engine mounts - shaft coupling - sten gland - prop are all matched, so it's well worth finding a good marine engineer, with experiance of wooden boats and seeking his opnion on the whole instalation.
 
Perkins engines are still available which will match what was in there previously, not the cheapest available but reliable and easily serviced. There are also a couple of comapanies that marinise suitable blocks at reasonable expense if u cannot afford to buy new units off the shelf. Other manufacturers too look at include Beta marine and Volvo units (new or second hand), u will get a fright however looking at new Volvo power;), a chat with a couple of marine engineers might be handy first.If u get stuck gimme a shout and i will point u in the right direction.
regards
Shug
 
If she is set up for Twins then by far the most sensible route would be to go for twins again.

I would advise fitting something close to the size in HP terms as came out. With something more modern you get a decent weight saving. Also look at the RPM, likely that the Perks that came out only did 2000 or 2500 rpm. Sticking with a low rev motor like that will halp with matching the props and shafts and gearboxes.

For reasons of cost I'd say look at marinising vehicle motors, looks at people like ASAP Supplies or Lancing Marine for marinisation kits.
 
Hi,

I am looking into getting engines for my 40ft wooden boat. Previously she has twin diesal perkins P4s but the previous owner removed them.

I have no idea of where to start looking for replacements - does anyone know what engine/s might make a suitable replacement? Should I stick to Perkins or are there other makes I can consider?

Also don't know what hp I need - she is 17 tonnes. Would one engine suffice or will I definitely need twin engines??

As you can see engines not my strong point so any advice in any form appreciated.....!:)

Talk to Lancing Marine, they are the people that can when it comes to engines and retro fitting!

Tom
 
No expert but a mechanic I was speaking to recently told me that Lombardinis slot into a Perkins engine mount without modifications.

His assessment of the advantages :

Save the cost of replacing the mount and realigning the shaft (say up to 20% of cost of engine.)
The motor is about 40% cheaper.
In his experience it's just as reliable.

FWIW

John
 
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Beware if considering a Lombardini as the smaller ones have aluminium heads/iron blocks and this may be cause for concern from a longevity perspective with salt water. Also If the engine is much lighter than original you may need to consider adding ballast to ensure correct trim.
 
Re-engining

I am considering re-engining my boat ... which has has mention several times in these forums. I am looking, ideally, for economical, low reving units of 170 - 250HP. I do anticipate changing the props too, but believe that I want gearbox o/p of about 800 - 1000RPM. Can anyone advise me on what to look for, and what to steer clear of ?.

Thanks
 
I have just replaced 4-108s with Nanni N4.50s on a classic wooden boat. Others are using Betas or Perkins. Heard less about Volvos in these sort of boats - possibly due to the nosebleed costs!
 
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