what would you do ? Blew up my outboard motor
 

About two months ago I purchased a used center console boat/motor/trailer. Made a good deal or so it seemed. Seller had some records indicating recent service within the past year or so. He offered to have a mechanic look over the boat or to do a lake test. I did not take him up on the offer which was my mistake. I've been fixing little things on the boat to get it ready for the maiden voyage. Ran the outboard in the driveway on muffs and seemed to run fine. This past weekend took it out and after about 7 minutes of running she quit. It would turn over but not fire. Got the boat back to the marina because of a good samaritan. Trailered the boat to a local marine mechanic and I received the call today...............cylinder # 1 is toast ! Apparently it ran lean and messed up the piston/cylinder. It's a 1988 Yamaha 90 hp three cylinder 2 cycle. It can be rebuilt but not sure that's good money invested because it is an older engine. New outboards are just stupid money but not ruling it out. I really like the boat so I think I'm going to keep it, but cutting my losses and selling as is could be an option. But I would prefer to find a newer used outboard. I could go with a 70/75 or 90. So what would you guys do ? I'm picking the boat up tomorrow from the mechanic and I'm going to ask if they get good trade in outboards.

I'd start with outboard motors on craigslist.... or attempt to rebuild it myself.

Can you get parts? are they expensive?

It ran lean due to sitting to long with old fuel. Plugged idle and pilot jets. PO probably had no idea. Hone that cylinder, 1 new piston, 3 sets of rings and clean carbs.

Give it a try. It's only a 2 stroke so doesn't need to be too fancy on the inside to run well. Check the oil feed is working properly then get out there and enjoy it.

I'd take it apart and see what you have to work with... If it looks terminal...move to the next step...

Outboard engines are really simple....

Where I live there a number of sources for parts for outboards.... I rebuilt my share of 40 hp Envinrudes back when I was in high school...

Having one hole be bad never prevented the old workhorse outboards run... yes they just thumped and sputtered but they could get you home...

Yeap

Get a second opinion
 

Unfortunately it is not uncommon to hear your story. It happens in the boat industry all the time. Mostly due to not being able to run the boats like cars for a good test drive. Hose and muffs really won't tell you much. First I'd get a second opinion on what is wrong, not sure how well you know the mechanic that gave you the diagnosis. Unfortunately the marine industry has many untrained mechanics floating around, or they may have some training but only on other brands and will claim to know it all. IMO I'd Find a reputable Yamaha service center. The Yamaha 3 cyl. motors are a pretty bullet proof motor. They are not the smoothest running motor but can put up with a lot of abuse. 7 min of running time lean does not screw up a piston, carbs clog up all the time with customers still running the motor. 7 minutes of running with a shut down sounds like an overheat. When was water pump and thermostats done? Usually it is number three piston that goes first due to water in fuel. My suggestion would be if it is truly just number one see if a quick hone and rings would get you running again. Whatever you decide stay away from rebuilt blocks. Once the cylinders are changed it is damn near impossible to get the idle right due to the lack of adjustments on the carbs. Pm me if you have any questions.

Did you get a repair quote from your mechanic?

There are usually several marine mechanics in every area that will work fairly economically if you beat the bushes.

I'd get a quote to repair yours first before making any decisions.

And also get some prices on parts and decide whether or not to repair yourself.

You can also find used motors on CL but you don't always know what you have with those.

Fix it yourself....its pretty simple and the parts are fairly affordable.

I would attempt to rebuild it. It is right there to work on! I'd at least disassemble and price parts / machine work and compare that to a good used. There's got to be DIY boat motor forums!? If I'd buy another motor, I'd buy the same one and keep the old one for spares.

JMHO!

G

had a 70 yammie 2str on a 17' aluminum boat and liked it. reliable and not terribly loud as 2 strokes go.

don't EVER underpower a boat.

Good advice from 88Cab. I wouldn't be surprised that once the engine cooled down that you could free the piston.

It's a 2-stroke, very simple. Rebuild it.

I picked the rig up today from the shop, they are an authorized Yamaha/Mercury/Evinrude dealer. Spoke with the head mechanic and went over the options. He stated # 1 cylinder is severely scored and can't be repaired. He said they put a borescope in the cylinder and the walls are severely scored. My guess is this cylinder was on it's way out with the previous owner and he may or may not have known. So option # 1 is purchase a new powerhead from Yamaha which is about 4k. Add to that 18 hours labor at 105.00 an hour to remove/install powerhead and rebuild the carbs, check the entire fuel system, new water pump and just do the entire installation so basically 6k. Option # 2 is go with an aftermarket rebuild he stated they primarily use Jasper engines. I didn't even know Jasper did marine engines but apparently Yamaha approached Jasper several years ago to do some R&D and one thing led to another. Going with the Jasper would be about 5k with the labor. Option # 3 buy a new outboard. Option # 4 try to find a good used one. Option # 5 try to rebuild it myself and finally option # 6 sell it as is. For now I'm going to save up some money and try to get smarter on these engines.

As per earlier, do a rough fix on that bore - hone piston + rings, and see how it goes.