Yamaha 115 2 strokes burning oil, lots of smoke!

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Hi everyone, this is my first post, I usualy find all my answers by reading threads here, such a nice forum btw!

Here is my problem, I went for a ride yesterday, everything went fine for the first 20 minutes or so, I was reving at about 4000rpm, for the time the engine gets a little warm. Then I pulled it WOT and in a matter of seconds, the engine went to a stall...

I tried to start it up again, it did but at very high rpm (4000 rpm) and with ALOT of smoke (and oil smell), this engine never smoked, even when cold starting ...

As soon as I lowered the rev, it would die on itself in a cloud of smoke.
I was able to let it run for many minutes by letting the throttle up and by applying the choke every few seconds...

I cleaned the water separator, spark plugs have been changed recently and the 4 pistons are working, not an electrical problem or something of that matter, I would have felt it if a piston was misfiring..

So my guess is that my engine is consuming way to much oil and this makes the smoke and thats also what keeps it from running at low rpm..

I checked the arm that controls the oil flow, looks very neat and moves easily, plastic is not cracked.

Where should I check for a solution, this problem happened "all of a sudden", it didnt show any sign before happening.

Thanks to anyone that could help on this!

Edit: to make my question more precise, what could cause to much oil getting into the engine?

Note: the oil tank in the engine compartment is not overfilled, the level is maintained between min and max.
 
Last edited:

douglloyd

Petty Officer 2nd Class
Joined
Jun 13, 2005
Messages
147
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

Year? When were the carbs off for a cleaning?
 

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

Its a 1987, last time carbs where cleaned is 2 years ago, around 100 engine hours or so ...

But I doubt it would be the only cause, the engine was runing perfectly before this happened.

Thanks for any input!
 

cousinabe

Senior Chief Petty Officer
Joined
Nov 13, 2001
Messages
765
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

check your fuel pumps. a torn diaphragm can let gas oil into crankcase and not provide enough fuel flow to carbs.
 

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

I've dissassembled the fuel pump, the diaphragm is not broken, there is a little bit of rust on the screws inside but thats it...

It looks rather neat in fact.

The carbs also look quite clean, this engine has never run in saltwater so it looks like new from every side you look at it.

Need help here : /

Thanks in adavance!
 

douglloyd

Petty Officer 2nd Class
Joined
Jun 13, 2005
Messages
147
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

As soon as I lowered the rev, it would die on itself in a cloud of smoke.
I was able to let it run for many minutes by letting the throttle up and by applying the choke every few seconds...

Classic plugged carbs...sorry.
 

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

Thanks for the input!

So my solution (I guess) is to disassemble / clean / rebuild the carbs with the help of a carb kit?

I still wonder how this can happen, woulnt I have only one carb plugged? Wouldnt the other two cylinders work correctly?

Hehe, sorry for my "noobness" with two strokes carbed engines, I am more familiar with 4 strokes injection ...

Thanks again!

Oh, also, where can I buy a carb kit (to do both carbs) for my 115ETLH?
I checked on the sponsored links here but I am not sure what I have to order ...
 

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

Heh, bad news for me I guess ...

This is the reply from customer service I just received :

"Unfortunately, we do not carry your requested item. We suggest posting a question on our Forums directory where you can communicate with thousands of boaters who may be able to assist you."

Anyone knows where I can turn to to get my carb kits?

I need help on that one ...

Thanks to anyone who can come up with some solution ...

EDIT: well after doing some research, I found out this:http://www.boats.net/parts/detail/yamaha/Y-6E5-14301-13-00.html
Looks like those carburetors are used on many outboards, on the 1990-1991 models it seems ... So do you think it is safe to buy the kit for 1990-1991 that iboats sells online ? Or is there a risk that something will not fit at all??

I'm quite confused lol... "Help"

TIA
 

usernamed

Cadet
Joined
Aug 18, 2008
Messages
6
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

No one knows ... ?

I am sure someone here has already cleaned a 1987 115HP's carbs ...

Thanks in advance!
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Yamaha 115 2 strokes burning oil, lots of smoke!

dunno
iboats doesnt sell the genuine yamaha service parts so they only can sell what is avalible aftermarket.
if the aftermarket bean counter deem that manufacturing a part for a 23 year old outboard wont make money they dont.
myself I have cleaned and rebuilt many carbs from the 1987 period.
however I work for a yamaha dealership and only have experience with genuine factory yamaha service parts.
 
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