Diesel power

pacman · 21 May 2004, 22:08

I am the proud owner of an ex MOD Pacific 22 RIB 9672. No engine or tubes, but this boat is fitted with a VosPower 115 jet drive which I understand can handle up to 400 Bhp at up to 3500 rpm. So the problem is where do I find a Diesel that can put out that sort of power and still fit it in the standard Pacific engine bay?

Also the hydraulic system controlling the jet reverse bucket is a mess, so I want to drive this using perhaps a standalone hydraulic pump like those for trim / tilt any ideas if this will work?

Any pointers would be greatly appreciated

Pete7 · 22 May 2004, 07:29

Hi, you might want to have a look at Mermaid Marine site for engines. they are a family business and very helpful. There is a huge amount of room in a P22 so a inline 6 on senible hp will go in there. They have a nice 6 cyl block that will go to 300 hp easily and being based on ford part are available.

http://www.mermaid-marine.co.uk/home.htm

Not sure about the jet have you spoken with Vosper Thornycroft ?

http://www.vosperthornycroft.co.uk/

Pete

Ian Austin · 25 May 2004, 21:47

Pacman
you could also try one of these.
www.marinediesel.nu

roohairy · 26 May 2004, 08:31

I was going to suggest them too Ian but didn't dare! I still think that they sound like a good idea though. I've heard more horror stories about samurai engines so the advice to stay away from them is justified.
And if you need a hydraulic supply I think an automotive power steering pump would be better than a trim / tilt unit if it's (presumeably) going to be running all the time?

Jonny Fuller · 26 May 2004, 09:47

Quote:

Originally Posted by pacman

Also the hydraulic system controlling the jet reverse bucket is a mess, so I want to drive this using perhaps a standalone hydraulic pump like those for trim / tilt any ideas if this will work?

A trim pump would be perfect as you can easily reverse the flow to up-down the reverse bucket, but be carefull, the pressure you'll get from a trim pump is massive, and could easily burst a ram unintended for such high pressure, or worse still, if the bucket mechanism gets to the end of it's travel before the ram does, something will break for sure.

mebbe a external pressure relief valve would be a good idea.

pacman · 27 May 2004, 18:03

Quote:

Originally Posted by Jonny Fuller

A trim pump would be perfect as you can easily reverse the flow to up-down the reverse bucket, but be carefull, the pressure you'll get from a trim pump is massive, and could easily burst a ram unintended for such high pressure, or worse still, if the bucket mechanism gets to the end of it's travel before the ram does, something will break for sure.

mebbe a external pressure relief valve would be a good idea.

Thanks Jonny

There is already a ram in place so I am planning to plumb something into that. I thought those tilt / trim pumps had some sort of over pressure relief built in, as I remember when I had a boat with a leg it would make a lower pitched whine when it hit the end of travel, I guessed that was some sort of pressure release?

As for engines, does anyone know what happens when you put 400Bhp in a Pacific 22? I like the sound of those Swedish Marine Diesels. Does anyone know what the standard (I.e Dover) diesel unit used to weigh so I don't upset the balance? Also there are no ridges on the underside of my hull like the standard Pacific 22, I guess they where removed to fit the jet in, any ideas if this will affect stability at insane speeds?

All input gratefully received!!

Ian Austin · 27 May 2004, 22:42

Hi Pacman
There is a pressure relief valve in the trim pumps, but it is set to a very high pressure, if you think that the pressure will push out an outdrive under full power and add to that the leverage, the rams are attached less than half way from the pivot to the prop.

The Pacific is rated to take 300hp, there is quite a price differance between the 300 and the 400hp, as the 400hp version is hand built to order, i spoke to a guy who is the agent for them in this country and they (Sweden) have managed to get even more power out of this unit, they are talking about 470 ish hp.

The dry weight of the Turbo Four engine and gearbox is 1050 lbs or 476kgs, from the documents very kindly supplied by the Master, Pete 7.

I have seen a 300hp version in the flesh and if i were to fit one i would fit a see through engine cover, as they look the Dogs B**locks.

Rogue Wave · 27 May 2004, 22:45

isn't a vospower Jet an revamped Pepe.......can they really take 400 hp

swginn · 27 May 2004, 23:19

Could it take up to 600hp??

I never knew that Lamborghini made marine engines? Now imagine what it would sound like across water, You'd hear it coming for miles. Sorry I know I'm probably way off topic as I don't know much about inboards. Just saw this

Quote:

Originally Posted by Ian Austin

if i were to fit one i would fit a see through engine cover, as they look the Dogs B**locks.

and thought it may be of interest?

pacman · 28 May 2004, 10:23

Quote:

Originally Posted by Rogue Wave

isn't a vospower Jet an revamped Pepe.......can they really take 400 hp

I have managed to get some info from VT Marine Products who have been extremely helpful. It seems they bought out PP Jets a while ago. I have an Impeller curve for the Vospower 115. The power band is max 500 hp at 2500 to 3500 RPM, the correct impeller will have to be fitted depending on the engine. I am going to fit it direct drive to eliminate any gearbox losses (thats power and money!)

Thanks Ian A, looks like standalone powerpack should do the trick.

PACMAN

Pete7 · 28 May 2004, 10:34

Pacman, I would have a chat with Jamie at Extreme Marine in Southampton. He has a P22 with jet for sale at the moment. Might be worth borrowing / chartering her for half a day so you can see what they are like. Think his a 200 hp engine in it.

I can't find the jet rib for sale but this is the other Pacific he is selling, he might also have an engine for you.

http://www.boatsandoutboards.co.uk/view/EML075/

http://www.boatsandoutboards.co.uk/view/EML055/

Pete

roohairy · 30 May 2004, 22:23

Pacman,

The P22 that Jamie is selling is at his yard, ie well inland! I had a look at it when I was there a couple of weeks ago and as far as I remember it had a PP jet, was just looking out of interest though! It is or was on boats and outboards - search for pacific.
The hydraulic pump on that one is driven by a toothed belt from the drive shaft, and I think there are control system problems there too. The one he had was fitted out as a jet boat by DMG of Southampton, not sure if they're still trading or not.
If you go the V8 route let us know how you get on as I am very interested... Sorry Pete I stil like the idea!