Should I rebuild 115 Yamaha

[ozenine]

Hello,
I just got the new boat and it came with the 1989 115 hp Yamaha. The bad part is that the engine is not good. The PO told me that the connection rod is broken. He took the motor apart in the fall and never finished it. So what I have is 2 buckets of parts. I checked majority of the parts and there is almost no rust, EXCEPT for some very light rust on the cilinder walls, but it can be wiped off with cleanex.
I called and asked how much is it to rebuild the motor and I was given a nice figure of 4500, I picked up my jaw from the floor and started debating on what I should do:

1) Buy a new old motor for 600-800 dollars and sell the yamaha in parts
2) Try assembling it with new rod - I have got the service manual.

Just so you know there is a bit of the benefit to the second option is the fact taht i will be forced to learn the whole motor and I have never done anything to motors larger than new carbs and carb setups.

Questions:
Where would I find parts for this motor?
What would you do?
Is this light rust powder uis something I have to be concerned (I do not have a plan to rebore the cylinders)?

 

[trendsetter240]

Re: Should I rebuild 115 Yamaha

Hey ozenine, from someone that just finished completely rebuilding an outboard for the first time, yes it is worth it to do it yourself. It's quite a project but if you are mechanically inclined and have the tools + service manual it's very possible.

It is not worth it in my oppinion to pay someone else to rebuild it. You will be better off selling that one in parts or buying a used motor with compatible parts so you have cheap spares.

Rust can be a bad thing...when metal rusts it causes etching on the highly polished surfaces of the bearings and other machined internal parts. The cylinders can be rehoned or rebored but the bearings & crank may need to be replaced.

First thing id check out is if the crankshaft, cylinders and pistons are still withing the specs provided in your service manual. If you are doing this all yourself then the cost of parts will be the determining factor.

Even if you have to replace the crank, pistons, connecting rods, bearings and have the block rebored it should still be well under 2k. (US parts prices)

There are many websites where you can purchase parts for a good price including the Iboats.com store. The next best would be your local Yamaha dealer which is convenient but a bit pricey.

Cheers~!

 

[trendsetter240]

Re: Should I rebuild 115 Yamaha

695$ for a complete rebuild kit at the site below. That is all you'd need if your crank and block is good.

http://www.powerheadkit.com/yamaha.htm

 

[ozenine]

Re: Should I rebuild 115 Yamaha

Thanks a lot, trend! I am quite excited about the project, but first I will have to sort out the parts and see if everything is there. Then I will see which parts need to be replaced. i do not promise that i will identify them all, but I know where to ask

 

[funk6294]

Re: Should I rebuild 115 Yamaha

Well the big question to answer before starting this is what condition are the block and crank in. I know you refereced rust, however the larger issue here is that since a connecting rod let go, what all did it damage in the process. Check the bottom of the crank case to make sure it did not crack the case also did it tear up the cylinder wall or the crank, did the piston damage the head when it contacted it. Any of these situations can lead to an expensive rebuild. If you find a bunch of damage a good alternative may be to put on either a used, or remanufactured power head. I just checked the Iboats listing for a remaned 1989 115 and they have it ranging from 2200 to 2700 (subtract 300 if you core is usable). Hope you get lucky and there is not much damage...

 

[ozenine]

Re: Should I rebuild 115 Yamaha

I will do the fill inspection and inventorization of parts this weekend (hopefully ), as I just got the baot couple days ago and was working late, but my hands are itchy to start it

 

[funk6294]

Re: Should I rebuild 115 Yamaha

BTW congrats on the new boat.

 

[Capt_Tom]

Re: Should I rebuild 115 Yamaha

The 115 is a great motor. While it is a little harder to rebuild something that you didn't tear down, it is not impossible.... I've done it on an old mariner. Like the previous posters mentioned, be sure of what condition your power head and crank (and bearings) are in before you commit your money and time. Good luck with it. If you decide to part it out, post it on here. I am sure some of us (me included) might be interested. You might also look on some of the web sites for an engine.... My friend bought an engine that was three years old, and still new in the box... I don't remember if it came from Atlanta, GA or maybe Greenville, SC

 

[ozenine]

Re: Should I rebuild 115 Yamaha

Thanks Tom,
I guess you answered my major question - is that a good motor to have? I do not waht to rebuild the motor and find out that even rebuilt it has no value like some Chryslers for instance.
When I will get myself familiar with parts taht I have I will post it here and ask you guys how to check bearings what is "good" condition of the powerhead.

 

[noelm]

Re: Should I rebuild 115 Yamaha

A rebuild is certainly possible, my biggest worry would be "is all the parts still there?" buying anything in a million bits, that you did not pull apart is a lottery at best (especially as it has been laying around for some time) I would reckon buy a second hand motor the same HP of similar vintage and keep your buckets of parts for spares.