At risk of starting a huge debate.....

taitharris · 08 February 2004, 11:25

Is it true that a Mercury 200hp V6 may be an EFI/AFI (or something like that) OR an Optimax. What's the difference? I have been told that the former is likely to burn fuel at alarming rates whereas the Optimax is frugal by comparison.

I know of a boat with a 2 year old Mercury 200 V6. If it is the EFI/AFI should I avoid it?

Pete7 · 08 February 2004, 12:02

Hi, The merc V6 range started with carbs in the late 1980s then moved to EFI (Electronic Fuel Injection) probably around early 90s, however the carb versions were still imported along side the EFI Engines. Although fuel injection EFI are not as fuel efficient as an Optimax. I think the EFI have now been dropped in favour of Opti's but you can still find the carb versions.

My 150 V6 Carb can do 60 LPH @ WOT were as the Optimax should be doing 35 LPH, certainly Wavehumpers does. However throttling back to a cruising speed sees 35 - 40 LPH.

If the V6 is in good condition then it could be worth buying as they have been around for a long time, props and spares are easy to come by and the technology isn't rocket science.

If you can live with the fuel consumption figures then go for it. Bear in mind that if you want to go really fast then that will need lots of petrol to create the power and it doesn't matter what type of engine it is. Even the latest Optis and 4 Stokes use lots of fuel at WOT. Throttling back to a cruising speed makes a big difference, ask Whiteshoes!

I think condition of the engine might be the key factor.

Pete

tue · 08 February 2004, 14:36

The 200 V6 is a good engine. (I have a carb version).

The difference between the Optimax and the EFI (if I remember correctly from the course) is :

The EFI engine only injects fuel into the combustion chamber, whilst the air comes in through the intake and goes around the crankcase like a normal 2 stroke engine with the oil thrown in aswell.

with me so far?

The Optimax has a seperate air compressor which helps build the air pressure up so it can be injected into the cylinders along with the fuel. This means the fuel-air ratio is kept as near to its optimum. This in turn means the amount of fuel burnt is alot lower. Usually since the EFI will chuck in more fuel than is required all the time so using more.

Does that make sense?

Pete7 · 08 February 2004, 14:42

Tue how much fuel are you using at WOT and a comfortable cruising speed ?

Pete

tue · 08 February 2004, 16:18

I haven't actually used my boat in the sea yet. I need to finish putting the floor in it

Pete7 · 08 February 2004, 16:42

OMG, thats quite serious, what are you doing to her then? taken any pics ? would be interested to see the inside of a Ribtec.

Pete

Ian Austin · 08 February 2004, 17:26

So if your not worried about fuel consumption, try these.

Ian Austin · 08 February 2004, 17:35

Or this.

nik · 08 February 2004, 18:44

It makes me wonder if any of these have been sold yet, as so far there is only an "artists impression" and no real pics.
nick

Jonny Fuller · 08 February 2004, 19:33

Quote:

Originally posted by Pete7
Hi, The merc V6 range started with carbs in the late 1980s
Pete

Pete, the V6 Merc was actualy introduced in 1976 as the 2 litre 150hp 'Black Max'.

Pete7 · 08 February 2004, 19:41

JF hi, hadn't realised they were that old. Did you have one of the first V6 then ?

Pete

Jonny Fuller · 08 February 2004, 20:04

Not a 76', but I think this one was a late 70's (150 Black Max)

tue · 09 February 2004, 18:15

Quote:

Originally posted by Pete7
OMG, thats quite serious, what are you doing to her then? taken any pics ? would be interested to see the inside of a Ribtec.

Pete

I bought her very cheap with a very rotten floor (its plywood). I have had to rip up most of it and take out some of the bulkheads. It would appear somebody had been inside her before to move the underfloor fuel tanks and had not replaced the floor properly. This allowed the floor to leak like mad and rotted the UNPROTECTED plywood panels they had put back in.

tue · 09 February 2004, 18:18

I am putting new bulkheads using shutterboard. This will be totaly reinforced with fibreglass to add rigidity plus to protect the wood from moisture.

I've put some more pics in the gallery now http://rib.net/forum/showthread.php?s=&threadid=3931

Dirk Diggler · 10 February 2004, 07:50

Quote:

Originally posted by tue
I am putting new bulkheads using shutterboard. [/URL]

Ever thought of a career change, i hear Falcon are looking for boatbuilders!

gavin · 11 February 2004, 18:34

When passing tro this centre of boating recently I noticed a big fighter aircraft on display outside the village, whats the signifiance of it

Jelly · 12 February 2004, 07:15

Hi Gavin
That the Hawk (I think) out side what I beleve to be Smiths Industries, how make parts for the areo industry.
I think its actually a memorial but never got close enough to read the plack.
I don't know the history, but I would guess the site could date back to when planes for the schnider trophy where built in the area - pure guess
Rgds
James