2 stroke oil coming from carburetor (lots of it)

[amahaork]

Read my post and find out where had I said that Yamaha service manual available from Yamaha web site?
If there is a will, there's a way.

[simpleone]

Thanks everyone for replying to my post. I'll take Amahaorks advice and check the position of the filler cap I didn't notice markings for the cap position. I'm liking the bad check valve idea because in my mind if the leak was due to the oil pump rod being out of adjustment, wouldn't more than one carburetor be leaking? I did take notice that the arm on the oil pump is not against the stop when the throttle is closed (which would be the idle position). I am assuming it shouldn't be totally against its stop at idle as it will be running and still need some oil. I do remember seeing check valves in the oil lines on a schematic, that may be the culprit but going to make sure cap is in right position.

Just for the record Amahaork I did post a picture and I am trying to get everything straitened out per yamaha's specs.

I downloaded a manual from Tradebit.com last night for ten bucks. It looks like its a factory service manual.

once again thanks for the reply's and I'll be sure to post what it was whenever I figure it out.

[Jason2tpa]

I'm liking the bad check valve idea because in my mind if the leak was due to the oil pump rod being out of adjustment, wouldn't more than one carburetor be leaking? .

No. You've got 4 oil tubes, 1 feeding each of the 4 cylinders. No doubt after 30 years these tubes I.D. have decreased, thus creating resistance. The leaking oil will travel the path of least resistance. As the oil begins to leak it finds this path, and subsequently a siphoning affect would occur. So I recon only 1 oil tube is acting as the sieve, which accounts for you seeing oil in 1 carb instead of 2.

Now you have a service manual, read up on the oil pump adjustments. I'd start here at the source before moving on to assess check valves.

[FabricGATOR]

Keep your cowling seal oil free...

When I got my boat, the previous owner had a similar problem that bled oil in the cowling. To this day, my cowling seal is soft and sticky.

I highly recommend that you wash it with a detergent like Dawn dishwashing liquid and then maybe even a wipe down with a little denatured alcohol followed by a light coat of silicon grease.
I sure wish someone would have done that to mine before I ever thought of buying it. It ran forward into the rigging tube also, what a sticky mess...

There was a fault or defect with my 2000 150's and I think it was the rubber cap misalignment or the tie wrap failed or was loose. Keep in mind that not all tie wraps are equal and the ones from Harbor Freight tools rate even below some of the worst. Get quality ones with the stainless steel tang is what I usually look for. I never suggest shopping the aviation nor marine isle at Home Depot but the manufacturer Ideal or Gardner Bender, one of those has the ss tang. Blue bag w/black-white of what I can remember.

[TownsendsFJR1300]

There was a fault or defect with my 2000 150's and I think it was the rubber cap misalignment or the tie wrap failed or was loose. Keep in mind that not all tie wraps are equal and the ones from Harbor Freight tools rate even below some of the worst. Get quality ones with the stainless steel tang is what I usually look for. I never suggest shopping the aviation nor marine isle at Home Depot but the manufacturer Ideal or Gardner Bender, one of those has the ss tang. Blue bag w/black-white of what I can remember.

Yamaha (may be Evinrude) actually has it's own plastic zip ties (if your engine came equipped with them) that look like the cheaper HD ones.

Except that the inside, where the "locking mechanism" is, it's CURVED. This allows for a tighter fit when zip tying small fuel / oil lines. Not terribly more expensive either. Your dealer should have them, HD won't...

[FabricGATOR]

Yamaha (may be Evinrude) actually has it's own plastic zip ties (if your engine came equipped with them) that look like the cheaper HD ones.

Except that the inside, where the "locking mechanism" is, it's CURVED. This allows for a tighter fit when zip tying small fuel / oil lines. Not terribly more expensive either. Your dealer should have them, HD won't...

Funny you should remind me of that Scott,
MPO looked at me sideways when I asked them to order the OMC tie wraps for me years ago. I was replacing the fuel pumps , the fuel hoses, all the nylon plastic tee's and 90º elbows with OMC factory parts on my 1986 70hp. They got them for me, in a little blue and white paper envelope, and boy did they charge me accordingly.

I am with you brother, when you take it upon yourself to deviate from the engineering, you are creating an experiment.

[simpleone]

Jason2tpa,

I will take your advice and make sure everything is adjusted per the manual. I didn't tell in my post that I disconnected the oil line to the leaking side of the carburetor and plugged it with a tapered punch and the leaking is stopped. If there was something out of adjustment causing pressure and the oil to take the path of least resistance wouldn't it now take the next path and leak from another carburetor venturi? I'm not trying to poke holes in your theory but you didn't have the information I just gave and it may change your mind. Its just so hard to get to anything on these outboards and I'm just trying to head the right direction the first time.

Amahaork,

I took a look at the cap on the oil injection bottle and didnt see a position mark on the bottle. However I did see an "H" on the cap and some arrows on the neck. Here's a couple of pics.

Thanks

[simpleone]

And by the way my tube has decreased in diameter over the last 30 years too

[amahaork]

c. when installing the oil tank and the oil level gauge, align the triangle marks on the oil tank with the oil level gauge and then align the projection on the oil tank with the slot on the air vent hole on the oil strainer.
d. when installing the oil strainer to the oil level gauge, align the projection on the oil level gauge with the hole on the oil strainer, and then align the slot on the oil level gauge with the AIR VENT HOLE on the oil strainer. page 4-20.

when above positioned wrong, air vent hole closed, create air bubble inside strainer, and oil from oil pump pumped via small tube to air intake.

[amahaork]

I am for 2 cycle engines for recreational boating.
It is cheap, easy to service, reliable.
Top bosses have different opinion on that.

[Jason2tpa]

Jason2tpa,

I will take your advice and make sure everything is adjusted per the manual. I didn't tell in my post that I disconnected the oil line to the leaking side of the carburetor and plugged it with a tapered punch and the leaking is stopped. If there was something out of adjustment causing pressure and the oil to take the path of least resistance wouldn't it now take the next path and leak from another carburetor venturi? I'm not trying to poke holes in your theory but you didn't have the information I just gave and it may change your mind.
Thanks

That was a smart diagnostic method, disconnecting the oil line. I agree with you in that if linkage was out of adjustment it would continue to leak. The only reason I can think of that would not apply to the above is if the remaining 3 connected oil tubes have a resistance greater than the static oil pressure. And since you've opened the oil tank, thereby exposing the system to atmospheric pressure, my guess is it would not take much resistance to prevent oil from flowing. That is of course IF the linkage is out of adjustment.

Besides this, checking the linkage is very simple and takes very little time. You can rule out all of the above just by confirming linkage is set to spec.

[simpleone]

Well, I put a syringe on the oil line where it connects to the carburetor that was leaking. I could draw oil from the line. I hooked the syringe to one of the lines that isn't leaking. I could not draw any oil from that hose. This pointed me to the check balls in the oil pump. I removed the top cover of the oil injection pump and blew brake cleaner through the oil line ports from the pump side of the cover. After getting brake cleaner in my eye and nose, I put it back together. The leak has stopped. I still have to take it out on the water and see if it holds but it isn't leaking right now. I inspected the check balls with a jewelers loupe and boy do they look like crap. It's a wonder they hold oil from running back towards the pump at all. I didn't have any luck finding replacement parts for that pump, I guess I'll just run it till I cant anymore and start mixing the fuel. Anyway, I'll report if the leak comes back.

Does anyone know what type of material the oil lines are? seems stupid to purchase hoses from Yamaha for 7 dollars apiece if I can buy a roll of tubing and cut the lines to size myself.

Thanks

[TownsendsFJR1300]

Most of the time, the Japanese hose sizes (Japanese manufactured parts) are just slightly different than non-OEM hoses.

If you go non OEM, make sure it's dead nuts exact... It's NOT worth burning an engine up...

Great diagnostic's BTW!

[Captn Dave]

You also have to be sure the hose is thick enough so it won't kink at the bends.

[99yam40]

Do not forget to clean the oil tank and make sure you have good clean oil in it.
old cruddy oil ,water from condensate, or sludge. will cause problems.
keep it clean

not sure what those check valves are made of on the oil system, but the internals of re circulation check valves on the crankcase on my C40 looked to be made of plastic. # of the 4 were missing and not checking when I checked and replaced