Diesel Optimax announced - Page 4

beamishken · 22 May 2015, 16:41

The problem with superchargers is they tend to lose efficiency over certain rpm hence volvo using both on their inboard diesels the supercharger for low down torque & turbo for top end performance we could debate the pros & cons of the various systems available all year but it's up to the engine manufacturers to attempt to build an engine.I'd assume they have done their homework on the possible ways of doing a diesel outboard but I can't realy understand why they have gone 2 stroke diesel it's been done before but engines have evolved to the point where I don't think any manufacturer makes a current 2 stroke diesel unless detriot still do

Searider · 22 May 2015, 18:57

What they've done is make an optimax run on diesel for the military only.

It has a standard Mercury transom bolt pattern and therefore can fit on any transom that has a mercury outboard of between about 100hp and 250hp.
Very easy for the military to unbolt their petrol motors and substitute these diesels.
They haven't developed a "new" engine.

I guess they used the optimax as a base as it is already direct injection.

It would appear it works but as it doesn't meet the emissions standards it's possibly not especially efficient.

Xk59D · 22 May 2015, 19:39

as said before, it is only a matter of time before one of the big boys does it.

i guess the first ones will be very very expensive.

speaking of which, i remember years ago someone told me they had converted an outboard to LPG up at loch lomond, great in theory i thought but getting fuel would be a royal PITA.....if it was even true!

cheers

JamesF · 22 May 2015, 20:17

As you say, I'm sure somebody will try it eventually. I'm not sure if it's more or less likely to be an established big name though. Many of the same advantages apply to diesel engines for boats and aircraft, but with the exception of airships and a couple of big, diesel-powered, pre-war bombers, the diesel aero engine scene was left almost entirely to a few relatively small and notably unsuccessful newcomers until very recently (2013–14). I wouldn't be surprised if the big outboard manufacturers waited until there was obviously a market to enter rather than try to create one, especially as they'd have to compete with petrol on weight, performance, reliability etc.

nocando · 22 May 2015, 20:32

MODULAR DESIGN - OXE

Anyone seen these.

ShinyShoe · 22 May 2015, 20:34

Quote:

Originally Posted by Xk59D

speaking of which, i remember years ago someone told me they had converted an outboard to LPG up at loch lomond,

You mean like this:
http://golehr.com/

The 50hp multi fuel referred to previously in the thread can drink diesel, standard gasoline, A1 aircraft fuel, LPG if I recall correctly. Paraffin may be on the list or it may be similar enough to A1...

Turbodiesel · 22 May 2015, 23:21

It is all to do with the mod single fuel
Policy, they dont like petrol on warships! And they can't always get petrol when out in the field (sea) it's not that straight forward in just replacing all the outboard powered boats with diesel ribs as the warship davits won't be able to pick them up, the cost of replacing the davits, new boats etc etc far outways the cost of developing a multi fuel engine. Plus for certain military users they need small inflatable boats that can be deployed rolled up in helicopters, used and deployed from submarines etc, for which a diesel inboard rib cannot be used. Hence the diesel outboard.

A1an · 23 May 2015, 00:15

Quote:

Originally Posted by Turbodiesel

they dont like petrol on warships!

But they'll carry nuclear warheads?

beamishken · 23 May 2015, 00:32

Quote:

Originally Posted by Turbodiesel

It is all to do with the mod single fuel
Policy, they dont like petrol on warships! And they can't always get petrol when out in the field (sea) it's not that straight forward in just replacing all the outboard powered boats with diesel ribs as the warship davits won't be able to pick them up, the cost of replacing the davits, new boats etc etc far outways the cost of developing a multi fuel engine. Plus for certain military users they need small inflatable boats that can be deployed rolled up in helicopters, used and deployed from submarines etc, for which a diesel inboard rib cannot be used. Hence the diesel outboard.

I get the reason behind it as you've described above the bit I don't get is why go down the 2 stroke diesel route to end up with something kind of half baked
I'd have thought they could work with one of the automotive engine suppliers (eg vw's 2.0 block) to supply a suitable core block & end up with a product that would have satisfied the military & could also be made to meet emissions regs & sold to a bigger market
It seems like they have spent a lot on R&D over a long period to achieve an engine with a very limited market.
Are they hoping that eventually they will get the optimax (diesel) system perfected & fit it to a range of engine sizes & utilise the bulk of the petrol engines components

Nos4r2 · 23 May 2015, 03:10

I suspect this is driven by the US military, hence the Optimax base.

ShinyShoe · 23 May 2015, 09:39

Quote:

Originally Posted by A1an

But they'll carry nuclear warheads?

The single fuel policy is partly practicality. Modern warfare is multi country. You can't have the US kit an aircraft carrier out to carry spare 91ron fuel and then land a British chopper on it that has a rib in it that wants 95 Ron. So they agree a single fuel. The same fuel the ship runs on so you just supply it all.

But in the interim while things are changing multi fuel makes sense. Oops we ran out of 95 Ron but we have A1 aircraft fuel ... Have some of that...

From a safety POV gasoline would be your least preferred fuel. If you believe the submariner last week things ain't perfect with nuke safety. So would you expect them to be with something we all handle daily? Spillages would be common...

I also suspect a fire near a nuke is a bad thing. When they move nukes by road as well as a convoy of armoured police vehicles, breakdown trucks, spare tractor units etc they have their own fire engine following about a mile behind. So I quite like the idea of them reducing the risk of fire on a ship carrying nukes etc...

Turbodiesel · 23 May 2015, 10:07

The reason it's what you call a half baked idea is because they have gone down multi fuel route, getting a diesel to run on petrol is not going to work.

beamishken · 23 May 2015, 11:21

Quote:

Originally Posted by Turbodiesel

The reason it's what you call a half baked idea is because they have gone down multi fuel route, getting a diesel to run on petrol is not going to work.

I must have misunderstood I thought the previous 50 was multi fuel but this latest announced bigger engine was purely to run diesel
Makes more sense if it's multi fuel