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Old 03 October 2007, 09:23   #11
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,539
Time to reawaken this thread....

Having finally managed to total up all my juice drinking data for the year, here's the resuilts:

ENGINE: Suzuki DT25, approx 1993.

Purchase price - Came with the boat. Subrtracting the cost of what I sold the hull for, call it 400 as a round number + a few spares.

About 20 mins of my time once a year + a day or so on the water fiddling with it to tune it for "real world" operation.

Warranty claims
None, but it expired years ago anyhow

Engine performance
Not bad all things considered! One thing I will say is that it has always got me home. Not necessarily at a nice cruising speed, but it has never totally refused to go. Lots of low end grunt, always useful when you have a water ballast to dispose of!

Fuel consumption
Very approx. 0.7l/Knautical mile average with a 13" prop. Includes some long sustained WOT cruising (oh, for a bigger engine!) and a fair bit of sitting around idling waiting for other people to capsise.
One cruise where the water was less than flat and so the entire run was done at 3/4 throttle it was nearer 0.5l/mile, with next to no time (relatively) spent at idle.

Oil consumption
Average 60.6:1 Nominally 50:1 at WOT, supposedly 200:1 at idle. Looks like I've not been idling too much then!

Noise levels
Not the worst 2- stroke I've heard by any stetch of the imagination. Can talk (loudly) above it at WOT. Once tuned it's remarkably smooth. Not sure what the noise is like in a following boat tho'.....

Would I buy again/Would I recommend?
Yes - if you can find a decent one secondhand! The overall size is tall & thin, so plenty of room on the transom for an Aux, even on a small rib.

Two small moans - access to service the carbs (not a problem if you throw it at your local dealer) - they are attatched by an annoying "sandwich" between the inlet and air box, the whole lot being through bolted, meaning you can't just take one carb out - you have no option but to disturb all three gaskets or not to touch. Sideline to that is that it's generally quite tightly packed under the lid, so a tad fiddly for servicing certiain items.

Other moan is the shallow water drive is pretty useless - it doesn't bring the engine out to a point where it would be worth leaving it down (or bringing it up to SW drive pos'n) - any beach landings have involved paddles from relatively far out from the beach. If you chose your cruise destinations with a little care this isn't really a problem.

So, that was the Suz. Hopefully soon I'll have a nice shiny "new" yam to appraise, but more on that anon.........

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Old 03 October 2007, 13:57   #12
Country: UK - England
Town: Blackpool
Boat name: Magic II
Make: Tohatsu 6.1
Length: 6m +
Engine: Evinrude 115 E-tec
MMSI: 235050189
Join Date: Oct 2006
Posts: 151
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Evinrude E-Tec 115

Purchase Price - came with boat but had only 16 hrs on it.

Servicing non as only every 300 hrs, but I have changed gear box oil and external fuel/water seperator filter. 20.00

Warranty claims - Non still 21 months left.

Fuel consumption - Not sure of mpg but averaged 12.6 ltr/hr over last 50 hrs mixed use.

Oil - Using XD100 3.785Ltr over same 50Hrs, the reason for such precise measurement is that is the size container it comes in.

Issues - Non with the engine but the fuel flow meter took a lot of playing with to calibrate so my figures come from what I have actually put in the tank.

Noise - very quiet only marginally noisier than an equivalent 4 stroke, but sounds good when you open the throttle.

Have run mainly with a Viper 13 7/8 x 17 S/S prop which gave a max with 2 up and half a tank (80 litres) of 39 Knots at 6000.
Changed to Solas Titan 13 1/4 x 19 S/S prop, same load 42 Knots at 5700, slightly less acceleration but much faster in the mid range 2500-4500.

Would I buy again - yes.

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Old 03 December 2011, 19:39   #13
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,539
Wow. Old thread, new-ish info not so much a reawakening as a complete rezerection! .

Merc clamshell 60Hp. Assorted bits of engine between 197x & 1989 Transom mount autolube disposed of.

PURCHASE PRICE: 200 (rebuild price 1500)

Servicing price - Call it an impeller & 20 mins of my time! (ignoring the rebuild!)


Fuel Consumption: 0.82L/kn mile, 0.84@ 25:1 running in

Oil consumption- 1/50th of 0.82L/mile.

Issues. - Total rebuild after it destroyerd itself. Solved (I hope) by rebuilding to latest build spec.


It's a museum. But my transom is rated (apparently) to 110kG, it ticked a lot of boxes. Early versions were prone to self destruction. Whether all the improvements work or not, you may need to wait another 4 years to find out....
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Old 04 December 2011, 03:44   #14
Country: UK - Wales
Town: N Wales Chester
Boat name: Mr Smith
Make: Humber
Length: 6m +
Join Date: Feb 2009
Posts: 4,956
Originally Posted by matt h View Post
Thanks for all the info,. just bought a new Opti 115 ,and cant wait to hear it, !!
90 75 115 and 125 are all a 1.5L block, 3cylinder, not V6. These are as quiet as a four stroke. 135 upwards are a 2.5L V6 and grrrrrowl
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Old 04 December 2011, 05:43   #15
Country: UK - England
Town: Northampton
Make: RibTec
Length: 5m +
Engine: Outbaord mariner 75
Join Date: Apr 2011
Posts: 506
Mariner 1991 75hp ELPTO 3 Carb woned from new.


1st service 200
2nd Service @100 hrs ish 270
3rd service @200 hrs ish 300

Had a stator coil at 17 years old with a full service and going over that cost me E700( euroes)
2 impellers ( i know but the water pressure is fine and no issues with cooling )

Engine alarm module off ebay 40 ( still didnt fix the allarm in the remote going off for no reason)

plastic oil lines 6 for them.

new sets of plugs every year.

Needs a new set of throttle and gear cables when I get round to it.

plenty of WD40.

Warranty claims

Engine performance
Not to shabby at all. can do arround the 36knt mark and good on fuel/oil really.
Acceleration is good nice and smooth and there when you need it.

Fuel consumption
Average - 1.2 nm per ltr depending on what your doing and how heavy your hand is on the throttle .

Oil consumption
Far too good. Had to check it was working sometimes! but it defo is.

Noise levels
ACE sound. its a 2 stroke. nice and smooth with the ussuall 2 stroke whine at wot.

Would I buy again/Would I recommend
Sure would and have done. I would get another if they stil made them.

So overall this engine has been awsome. no issues as such and the stator . well I was told the origional ones only had a life span of about 5 years and had a known problem with breaking down so I did really well TBH.

And considering the total rig cost in 1991 was 10500 for boat engine and trailer I think I am doing really well.!!!
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Old 04 December 2011, 09:53   #16
Sea Witch's Avatar
Country: Ireland
Town: clifden
Make: Fletcher Bravo Arrow
Length: 5m +
Engine: Yamaha 175
Join Date: Jan 2010
Posts: 43
Mariner 1987 75hp 3 cyl

New stator 2 years ago - 400 euros
Cdi 2nd - 150 euros
Voltage reg - 200 euros

This won't give up !!! Compression 120 psi in all 3 cyl , bullet proof engine !

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