Repowering 530F to 4 Stroke

[Pedro Jnr]

Hi Guys,
I'm the proud owner of a 1995 model Haines Signature 530F currently powered by a 2 stroke 90HP Mercury

Great rig, I fish the Banks on a regular basis and currently average about 20 litres of fuel per hour, I usally sit on about 4,500 RPM which pushes me along at about 24 knots, all good stuff but she is starting to get a little long in the tooth and I am now considering my options for a repower

Anyone out their weighed up the pro's and cons of going 4 stroke, I'd like to hear the real pros and cons from a boat owner, not a sales man!

Cheers

[matken]

not quite on the same scale, but i went for a honda 20 to replace a old 25 hp 2-stroke. very happy with the change.

[purple patch2]

G'day Pedrojnr a 115 merc opti max would be the go. performance hull performance motor. That's a bit of a brash statement(I own a Signature with merc opti max) but hole shot of the two stroke is a bit faster. Two stroke serviceing is every 100hrs four stoke every 50 hrs. Four strokes are a bit better on fuel efficiency and are a bit heavier. Price close. When it comes down to it,its how you use your boat and personal preferance. These are some of the things I considered when repowering. Hope this helps. Cheers Roy.

[Spaniard_King]

Two stroke serviceing is every 100hrs four stoke every 50 hrs. Roy.

Roy, I think you maybe missinformed. I don't know of any 4 stroke on the market which requires servicing every 50 hours Standard service intervals are the same for both 4 and 2 strokes.

Pedro,

do you need more HP or are you happy with what you have?

If you are happy with the 4 stroke stick with it, there are some new inovations that have been released in the 90hp bracket I suggest you do some homework on them before making a decision.

you also need to decide who is going to service the engine probably the most important factor in the decision IMO. No good having a great engine and have it destroyed by dodgy workmanship at a dodgy dealer

cheers

Garry

[craigie]

Pedronjnr,

As roy has mentioned a 115 HP Opti on your rig would be very sweet.
I have one on a 5.4m Cyclone and it's perfect.
Have put 560 hrs on it in 3 years, it purs !!!

Your fuel econ is around the 20 litres per hr on 4000 revs for 24 knots.
Can give you all the fuel figures if your interested.
Trolling econ is very good.

115 Optimax is very competitively priced as well as you have the option of the smart craft gauges.

I gues it's just one of many good options available at the moment.
Happy Shopping !!

Cheers
Craigie.

p.s Here is a pic of mine fitted up with a custom OCA Outboard Cover.

[purple patch2]

G'day pedrojnr and spaniard king sorry about the missinformed info its just that suzuki states that an oil change every 6months or 100hrs. And yes some people can get 100hrs up in six months be it a four stoke or a two stroke. Its interesting that mercury marine state 100hrs or 1 year what ever comes first. So if the user of the four stroke motor only has average usage(hours run) when would he have his /hers 6 month 100 hrs oil change done. I've seen motors 10 years old with 300 hours on them. Example old mate goes from jacobs well to the bedrooms 10 times a year. Stays overnight and heads back to ramp after enjoying himself greatly in his boat he's lucky to have put 3/4 hr on the clock how long before 100hrs comes up.In the first year he would only have 7.5 hrs on the clock. Fishermen and women that don't send much time trolling don't put to many hrs on the clock, So where does old mate the suzuki owner stand on this one. Change oil at 6months or 100hrs. Even Fishing Offshore with 150 km days 20 times a year 4hrs running per trip (no trolling) is 80 hrs if you get the time and wheather whatdoyareckon.Cheers Roy.

[PADDLES]

have a look at all of them pedro. the direct injected 2s motors as well as the 4s ones, they're all pretty good. have a look at as many engine reviews as you can get your hands on, boatpoint is a good starting point for the reviews. i would have thought a 90 would be a bit sluggish on a boat the size of yours, but if you're happy with the performance then stick with it, just bear in mind that the 4s at 90hp might be a bit slower off the mark than your existing 2s 90.

[Noelm]

you will never get a "straight" andswer on this, there is about 1/3 who will say go a 4 stroke because... then 1/3 who will say go an etec/opti/whatever because.... then the rest will say go for a specific brand in those options or stay with the 'old carby" because... get what I mean? I don't know how many times I have said this, go for the dealer that has the best service/workshop and customer service and is reasonably close by, then really you can forget the brand, because over a period of running time the fuel consumption and service costs will even out, a 4 stroke needs oil changed and thrown away, a 2 stroke burns it, at certain speeds some are better, but over all they will compare very closely.

[Smithy]

I reckon it all comes down to it you troll or not. If you do, there is no question at all, you should go 4 stroke. If you don't, you might as well go direct injection 2 stroke or as other people have stated go with the brand or dealer that is going to do the right thing by you in the long run.

Personally I am a 4 stroke fan because I troll. For a bit of perspective, the last 6 months I have been on boats with a 225 4 stroke Yamaha, 225 Optimax, 200 Etec. The Optimax was the most economical by far. The Etec the most disappointing but the Yamaha the esiest to live with. I like the fact of the Etecs being white to help disguise the seasalt on them and the OMC control boxes and motor support brackets are good to use. The two Etecs I have had anything to do with have both had an oil stain develop out of the exhaust port on the leg which was a pain to keep clean. Typical even of the old 2 strokes. Maybe the Mercs do it as well but on the black colour it is harder to see. The black of the Mercs and grey of the Yammies seem harder to keep clean.

The Yamaha we racked up over a hundred hours in a couple of weeks and as it was out of warranty, we did an oil change ourselves. Therefore in that 100 hours the only stuffing around we had to do was an oil change taking an hour or so when we had the time to do it one afternoon. Other than that it was just fill up with petrol at the servo.

The Etec was painful to use by comparison. We racked up around 100 hours use in 2 weeks. Each morning we had to check the oil level and top up the hard to get to oil reservoir under the seat and lie on the wet carpet from the night before. Each afternoon we had to decant oil out of 20 litre tub I bought and put it into 4litre bottles. At sea it had a definate smell and every now and again visible smoke. Talking about it on here before maybe it wasn't tuned right. We were using the more expensive XD100 oil. Cop that at close to $60 a 4 litre bottle. Instead of getting better than a fuel to oil ratio of 100:1 it was worse than 50:1. To make matters worse talking to other blokes at the servo with bigger boats like 680HHs with 4 strokes they were using less petrol per day with their 4 strokes. Obviously sizes like 90 Etecs you are going to go a million miles for each litre of oil and the oil reservoir is under the cowl making life easier but it was still a pain to go back to having to deal with oil, having spare oil onboard etc. and paying for the bloody stuff, making sure you had enough on hand, just like old 2 stroke days. For the 100 hours we were only 1/3 of the way to a service at least.

Now for the Optimax. The boat I go out on with it is just a walk on walk off proposition so I don't have to deal with the day to day oil use on it. I think the Mercury oil is slightly cheaper than the Etec oil and I guess it gets used at a similar rate. There is still a slight smell whereas with 4 strokes there is no burnt oil smell, there is less vibration and less noise. The other thing you notice with the direct injection 2s over the 4s is the way the revs vary on the back of swells and stuff. 4 strokes must have more torque or something and seem to be able to sit at any given throttle setting much more happily. Direct 2 strokes I think you will have to play with your throttle more in rougher conditions. I would guess the HPDI Yammies are the same. Interestingly a mate repowered with the same horsepower HPDI Yamaha over a Ficht and preferred his Ficht better. That was about the time of the OMC dramas so due to an insurance thing he took the opportunity to get out of the Ficht when he could.

With the trolling aspect, 4 stokes have stood the test of time but all this new technology is unproven in the trolling application if big hours are involved. Have the Americans designed these motors for trolling applications or are they for American freshwater which is there biggest market? How many ski boats or US Bass boats do you see trolling? Time will tell!

[Noelm]

Jesus, you must have done some fishing!! 100 hours in 2 weeks with an etec and the same in a boat with a yamaha, must have never got out of a boat!, and perhaps it may have been easier if the etec was installed better so you did not have to get on the floor to check the oil every day (by the way, I DO NOT have an Etec) but I guess that was your first hand experience, and that is better than the old "I know someone who knew someone who might have said...."

[Smithy]

The 100 hours was over 4 weeks or so with the Yamaha in Cooktown and the 100 with the Etec was down at Port Stephens. 10x10 hour days are pretty easy to achieve but I think we got out 11 days in total.

With the bigger oil reservoirs where else can they mount them other than somewhere in the bilge/battery area?

[rat_catcher]

I reckon it all comes down to it you troll or not. If you do, there is no question at all, you should go 4 stroke. If you don't, you might as well go direct injection 2 stroke or as other people have stated go with the brand or dealer that is going to do the right thing by you in the long run.

Thanks for taking the time to write this long post Smithy. Very interesting read.

[Noelm]

agreeed that the tank/bottle is usually mounted on the floor, but a simple "fuel filler" (in this case oil filler) on the deck somewhere might have been a better setup, I have seen lots like that, OH and I was not "having a go" at you, it was just a lot of time in a boat in a short time frame.

[purple patch2]

G'day Pedro jnr well theres some good food for thought from out boards uses. Good wrap up Rob. All the new generation outboards are good technology. just a bit on opti hpdi two stroke oil consumption on a 135hp 29.6hrs for 7 liters thats about .25 L/hr and hpdi oil is $45 to $50 per four liters. I don't know as much about 4storkes (I've fished out of acouple of boats with 4st pushing them) and I think spaniard king must be a outboard tech and would be a wealth of knowledge on 4strokes. another issue with repowering is getting the best price for your old motor. To do this it seems a matter of towing your boat all over town to ,having outboards tech pulling spark plug out checking compression,gearbox oil etc.Then on to the next dealer. There must be a easier way. Anyway have fun checking them all out and more fun when you get to use your new outboard. cheers roy.

[ozscott]

boatpoint.com has very good info as to the newer outboards...see if you can rustle up posts by Rodbolt who is a mechanic with truck loads of experience. He is not a fan of the high pressure direct injection 2 strokes for various reasons, and he is of the view that the 4 strokes have their own problems....I really dont know, I can only speculate about things such as the need for the valves to be adjusted etc, but perhaps these days there is no need for that. It would be helpful to have an outboard tech, if there is one on this site give some pros and cons, aside from oil burning requirements etc. We need the low down baby!!