Opti Overhaul



riverview

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better get a prop on that thing and in the water to break in before more garage running lol
 


raider

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i sure miss the smell of my old black max in the morning - but not the carbs and the hard starting...
 

Davey Crockett

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Well done Eye. There is something to be said here about kids growing up around Dirt bikes or Derby cars, Race cars, Snowmobiles ,Tractors ,Go carts, bikes . I figured if you were brave enough to tear into it you would get it done but when she laid on the bench that long I bet you scratched your head a time or two going back together. Did you go to a mechanic trade school or pick it up along the way ?

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Jack of all trades master of none but you still got er done lol . I see you are breaking it in like you plan to use it . For once in my life I did a proper break in on a new motor in my boat , It was boring as hell for 40 hours @ 2700 I think it was . No idea if it pays off, That was my first time.
 

eyexer

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Well I grew up kickin around my uncles implement dealership and my grandpas farm. Started racing motocross at 14 and split the cases on my first motorcycle at 14. So tinkered with those for years. When I was 26 I went to Aircraft mechanic school but when I got out the economy was horrible and there were no jobs. So I took a mechanic job for a couple years but eventually got into construction. Built homes for a long time but got tired of piss poor help. So I went to work for the cat dealer. Worked mostly on industrial engines and most were on the drilling rigs. Then went to work for a drilling company on their rig engines. That company pulled out of ND so I started pumping wells. All my life I’ve always fixed my own stuff. Only things that ever went in were under warranty. I just can’t come to grips with paying a company money to fix something I can do myself.
 


Allen

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I dropped the lower unit on a late 80s Mariner in order to replace the water pump. About shit myself when the bearings bounced out the garage door. It was a real WTF was that moment.


I'm not horribly shy about doing mechanicking, but today's stuff is just beyond my experience (and tool box).

Tis such a fun read I actually started all over from the beginning.
 

Rowdie

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overhaul kit consists of pistons, rings, main and rod bearings, all gaskets/seals. This won't need any boring I don't think. Won't know until I run the hone through it. Boring can run up to $70 per hole so I'm gonna try not to do that. However I can just bore the two bad ones if needed and hone the rest. I have about three hours in it to this point. I would guess I'll have 20 hours in it total. I will also rebuild the air pump and send the fuel and air injectors in for cleaning. That will be about $25 a piece for those to get cleaned. So $300 just for them. Overhaul kit is about $1350. I should be able to get it all done for about 2K. You can buy remanned power heads for about $3500. So I'll save about $1500.

So now that it's done, was the $1500 savings accurate? And were the savings worth 2 years of not having a boat?
 

eyexer

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Good question. As I get older I also realize I’d rather spend my time doing other things. Next time I would probably buy a rammanned one. The time down could have sucked but turns out I didn’t have much time to fish during that time and had access to a nicer boat lol. To a degree it was fun and also a pain in the ass. It was cool learning about how different engineering and technology is used. And how you have to really research these engines before blindly diving into it. They all have different things manufacturers do in terms of engineering. But I can tell you I know this thing inside and out for the most part. And it was pretty cool to see the inside of one with 1000 hrs on em. These motors can easily go 3000 hrs if you keep good oil and fuel in them.

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I dropped the lower unit on a late 80s Mariner in order to replace the water pump. About shit myself when the bearings bounced out the garage door. It was a real WTF was that moment.


I'm not horribly shy about doing mechanicking, but today's stuff is just beyond my experience (and tool box).

Tis such a fun read I actually started all over from the beginning.
That would surprise anybody lol. Not supposed to happen.

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Couple of the interesting things I leaned on this was that they have a specific port piston and a starboard side piston. Which was quite interesting. Also how the oil system works exactly. I never really paid any attention to the oil system but when your gonna start one up with that kind of money and time invested you want it working. They use crankcase pressure to pressure up the big oil tank in the boat. That pressure pushes oil to the engine mounted tank. Then it gravity feeds to the injection pump. You have to bleed the air out of the big line from the boat mounted tank into the engine mounted tank. So you have to leave the cover off the engine mounted tank while you run it to let air out. When it starts to over fill you cap it. The injector pump is actually a little piston driven pump. It’s speed is determined by the ecm based on engine rpm and load. So when I had it put in break in mode it actually doubles the speed of the injector pump. Off the injector pump there are seven small lines. One to the reed block for each cylinder and one feeds the air pump for lube. You have to purge these lines of air also. I was so concerned about that I actually took each one off and used a 20cc syringe with oil in it to fill these lines and push the air out. With direct injected outboards you can’t simply put oil in the gas for added protection because the gas is injected above the piston. Which isn’t where you need the lubrications. On normal two strokes you have fuel, oil and air all coming up through the crank and into the cylinder. That normally lubricates the bottom end. But with no fuel going through there with direct injection you don’t get the luxury of oil in gas. So on these they inject the oil just inside each reed block for each engine and used the intake are to help atomized the oil and it essentially sprays around in there.
 

shorthairsrus

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riding lawn mower -- i started it last night was going to pull around the rake. It was idling and then just stopped. I was all over the fuel supply thinking thats it. It started shitty for the past two years and acted up from time to time. I was like yup that shitty fuel. --- i pulled the plug and was suddenly embarrassed the plug was so corroded. My wife was like have you ever replaced that - nope 20 years old.

Thats the limit that this guy can do any mechanic work.
 

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