Cylinder boring evinrude 115?

BuckTroop

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I am recently down and out for the second year in a row. Motor (Evinrude e115tleor) has 75psi in lower port side cylinder compared to 120psi in the other 3. Upon disassembly i have come to find out that this motor may have been opened up before. I bought it for $600 in april 2012 to replaced blown ProV 150 and it has run pretty good up until a week ago when I could not get it started. That led me to check compression. I am quite certain that a previous owner had only the starboard side bored to 0.030 over.
Is it necessary to have all four cylinders bored to 0.030 over or was the previous owner fine to have rebuilt the motor leaving port side standard? I have the motor completely torn down as of tonight minus crank and piston removal. Waiting on service manual to continue and advice on this situation. From what i can tell thus far the bad cylinder doesnt seem bad at all but the top of the piston has some knots (for lack of a btter word) around the edge. I am really in no position to be spending alot of money but dont want to lack the essentials putting it back together. Any advice or input would be appreciated. Thanks!
 

F_R

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Re: Cylinder boring evinrude 115?

It is perfectly OK to bore one or more cylinders. I did it all the time when I was an Evinrude dealer mechanic.

EDIT: Um, a disclaimer. Your motor is much newer than what I worked on. Things may have changed since then. Better verify.
 

BuckTroop

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Re: Cylinder boring evinrude 115?

I have heard and read both ways bout 50/50 really . I think honestly i should probably bore it to match the others thinking in my mind that it's the best way. Perhaps if someone could give me a ballpark price for two cylinders i would feel better going one rout over the other. I gotta add that i will need to replace the piston in that one cylinder. Any opinions (anybody) on replacing bearings on the crank/ rods. Would rather not but dont want to have to open it up for worst repairs later.
 

emdsapmgr

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Re: Cylinder boring evinrude 115?

I've replaced just a single piston before. You'll want to match it to the other 3 (if they are Bombardier-original-pistons, stay with a factory piston.) Best to put 4 new ringsets in. If the bearings are not blue from overheat, I've reused them with no problem. You'll want to determine the cause for the ring failure in that bad cylinder. Overheat, debris in carb jets, etc.
 

Haffiman

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Re: Cylinder boring evinrude 115?

You may replace individual pistons and mix std size and oversize provided they are all from same manufacturer.
 

BuckTroop

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Re: Cylinder boring evinrude 115?

Thanks for the responses guys. One more question on this. If i do bore the port side two cylinders to .030 do i have to buy bigger pistons or is it just the rings that make up the difference?
 

Daviet

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Re: Cylinder boring evinrude 115?

Yes, you have to buy bigger pistons. Make sure to buy the same brand of piston.
 

emdsapmgr

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Re: Cylinder boring evinrude 115?

Replacement oversize pistons will come with a the oversize stamped on the crown, such as: .030
 

F_R

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Re: Cylinder boring evinrude 115?

Boring cylinders that do not need it is a waste of money, and metal. You may need that metal for a future repair. Once you bore it out, it's gone.
 

camalot

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Re: Cylinder boring evinrude 115?

I rebore and hone 100's of cylinders every year as I build performance two stroke engines for classic race bikes. It's fine to mix and match for the first over IMO. One of the biggest ring eaters are the lack of chamfering to the ports after they have been rebored. As pointed out if you stick to the original manufacture for the piston then all will be good, it's only when you start to mix Wiseco forged pistons with cast pistons things can go wrong.
If the other bores measure to spec get them to de-glase them at the same time.
I charge $80 CAD/bore
 

V153

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Re: Cylinder boring evinrude 115?

It is perfectly OK to bore one or more cylinders. I did it all the time when I was an Evinrude dealer mechanic.

EDIT: Um, a disclaimer. Your motor is much newer than what I worked on. Things may have changed since then. Better verify.
I believe the rule of thumb is it's okay to bore just one cylinder in an inline motor, but if it's a V you should do them all. I think ...?
 

F_R

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Re: Cylinder boring evinrude 115?

I almost constantly had a twin, 3-cyl, and/or V-motor torn down for rebuild back in the late '60's - early '70's. Bored one, two, three, or more, even on V-6's. I'll guarantee you could not tell the difference. I did the re-bore work for all the other outboard shops in town too. Even did a bunch of Saab two-stroke loopers (cars).
 

V153

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Re: Cylinder boring evinrude 115?

Even did a bunch of Saab two-stroke loopers (cars).
Killer! My Uncle Gary had a Saab Sonnet that was balls to the wall. That thing was incredibly effing quick. Sounded like a lil Ferrari.

But I digress. Bore as many cyl as y'onto ...
 
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