115 Gas in Oil

My friend has trouble with his Yamaha again. This time it has excessive oil in crankcase, 1 inch above full. It smells real strong of gas. Oil was changed before weekend trip of about 10-15 hours then checked on yesterday. Oil was changed and drained yesterday and another trip out of about 4 hours shows no gas in oil and no rise of oil level on stick. He used HD40 oil this time for this trip. He has been using Castrol 10W40 at very regular intervals. We ran motor yesterday on the hose and starts up first crank and idles beautifully. Motor feels warm to touch after 10 mins. When you pull the dipstick while idling, there is a positive pressure on the crankcase. Is this normal? Pulled plugs and all looked identical. We do not have the service manual on this motor yet and do not understand what type of crankcase ventilation this thing has. Maybe this is malfunctioning? Motor still has 1 month warranty and will probably be going back but we wanted to do some checks to know what is wrong before we let the dealer have it. The regulator went out on it and was not covered by warranty as it is an electrical part. We wonder now if the gas in the crankcase was what was overheating the regulator like I mentioned in an earlier post. Any suggestions as to what checks we can make and specifiaclly how to check fuel pump for leakage?<br />Thanks

Re: 115 Gas in Oil

Gas in the oil is a fairly common problem with the Yammy 4 strokes, Freeze.<br /><br />The engine is not getting up to temp quickly and is running too rich. Excess gas is getting into the crankcase.<br /><br />Needs a new hotter thermostat and it needs to be run hard to better seat the rings. After 10 minutes the engine should be uncomfortably hot to touch.<br /><br />Take it to the dealer.<br /><br />Good luck.

Re: 115 Gas in Oil

Update!<br />My friend went to dealership and was finally able to get through to Yamaha's warranty service. Dealer says that sounds like motor was not broken in right or wrong prop causing it to lug. Not! Then he says that if we followed the owner's manual for break-in, then we done it wrong and that's why it's doing it. Call to Yamaha also yeilded bad news... They said sounds like it wasn't a warranty problem and that it probably will not be covered. We have got to find a manual for this motor and look into it ourselves are he is going to get screwed. Will post back with any future developments. <br />Oh by the way, Yamaha just sent him a flyer letting him know his warranty is about to end in another month and asked would he like to buy another warranty agreement for 3 years for $1400. Yeah right!

Re: 115 Gas in Oil

This is the same issues I am having in the Merc section (I posted). I have a 115 f4 stroke efi 2002. Yamahs and merc 115 have the same power head. I am currently going to seek legal representation. to many people with this model having problems. The dealer put a higher temp thermostat in the engione but the same problem occurs. I have a extended warrenty on mine, but they say its not a issue. We will see.

Re: 115 Gas in Oil

hello<br /> its not just a yammy problem. its an industry wide problem. it can usually be traced to a problem with the t-stat and improiper breakin. you would not believe the motors I plug the laptop to at the 10 hour service to find 9 hours below 1000 RPM and I have to note an improper breakin.<br /> take it to the dealer <br /> good luck and keep posting

Re: 115 Gas in Oil

Update<br />Went out with my buddy Saturday morning. We changed oil before we went out with 10W40. Made it across lake about 15 miles and cruised through fishing different spots in marsh. At one point motor would not start. Checked and found no power to plugs? Then suddenly got spark, put wires back on and it cranked right away and we fished remainder of day and back across 15 mile lake. <br />Motor went to shop on 6/7/04. They just called 6/9/04 and said that it had an extremely long update list. Would not tell us what the updates were, but that it was over $1000 in warranty parts including hotter thermostat, ICU, and other parts not mentioned. Did not acknowledge any codes in ICU. Said this motor has issues and said he didn't think even Yamaha knows what is wrong with these motors. <br />If anyone else has this problem please E-mail me and lets see what we can get Yamaha to do about this. A motor that costs this much money should not have these problems. Warranty ends on the 11th of this month and not sure what to do now. Should warranty coverage extend over because of ongoing flaw.<br /> <br /> <br />PS: How do I find the email address for members here? I very much like to talk with you Tucker1, but cannot find out how to email you.

Re: 115 Gas in Oil

Freeze, email me at <br />t.glazier@comcast.net<br /><br />I can tell you from first hand experence what they are going to do with your engine. Bottom line is that there is a design flaw with the 115 4 strokes.

Re: 115 Gas in Oil

Re: 115 Gas in Oil

I'm having the same problem with gas in oil with a 2000 T-50. Does anyone know if this is a common or known problem with the T-50 as it is apparently the case with the 115 four strokes.<br /><br />I was hoping for a quick and simple fix but now I'm starting to get really worried. Thanks.<br /><br />Bob

Re: 115 Gas in Oil

I'm having the same problem from my 2004 Yamaha f115, ie. gas in the oil. Any one have any luck resolving it? I do have one year left on the warranty

Re: 115 Gas in Oil

chug bug,<br /><br />Probably nothing wrong with Your Yamaha F115 4-stroke.<br />Read here for some help understanding why.<br /> http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=30;t=007603

Re: 115 Gas in Oil

TUCKER1 said:

Freeze, email me at <br />t.glazier@comcast.net<br /><br />I can tell you from first hand experence what they are going to do with your engine. Bottom line is that there is a design flaw with the 115 4 strokes.

Click to expand...

I am having this issue with my 2000 F115. (gas getting in the oil) Is anyone aware of any resolutions for this?? Did Yamaha come out with a fix?

Re: 115 Gas in Oil

Hi, Gottafish.

Welcome to iboats.

It's a waste of time to hijack a 3 year old thread.

Start a new one.

Re: 115 Gas in Oil

My 2003 yamaha 115 4 stroke does the same thing,

Re: 115 Gas in Oil

Go to Engine FAQs. Read about 4 strokes "making oil".