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Oil leaking in engine compartment

RobT

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Hello,
I have an oil leak in engine compartment. In the first channel is blue color and second channel is dark-black. Could someone please tell me what the issue is and where it's coming from? Please see picture below.
Thank you in advance.
 

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4x15mph

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Hard to say with that single pic and view. You still have oil injection, right? I would check that each oil line is attached to the underside of the arrestor. I would also check all connections from the oil tank to the oil filters and pumps. It seems less likely that it is the latter since the oil is collecting in the back compartment of the boat which is not where the tank and filter would leak to.
 

RobT

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Hard to say with that single pic and view. You still have oil injection, right? I would check that each oil line is attached to the underside of the arrestor. I would also check all connections from the oil tank to the oil filters and pumps. It seems less likely that it is the latter since the oil is collecting in the back compartment of the boat which is not where the tank and filter would leak to.
Yes, I still have oil injection and it seems dry where the oil filters are located.
 

itsdgm

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How long has the boat been sitting? The blue looks like it could be marine grease from the seal or coupler. But it would have to have been sitting a while for it to liquefy like that.

Only other oil would be the pre-mix. Does it match the color of oil you're using?
 

itsdgm

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Could it be residue from any oil that you might have sprayed down the engines with?
 

RobT

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Could it be residue from any oil that you might have sprayed down the engines with?
On the engines I have sprayed silicon lubricant nothing else. I'm wondering if the blue oil like complete my out of the zerk where you put intermediate housing grease!!! Don't know. But the other residue is dark color like oil mixed with water sort off.
 

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Check for bad hoses or clamps on your exhaust , the exhaust has oil in it and when a hoses leak or the water box wears a hole in it etc the exhaust and water with oil will get in the hull. The oil will look dark or black from the carbon during the combustion process, also the engine may feel a bit sluggish since it is pulling in exhaust gases from the leak. Also those were NOTORIOUS for the oil injection lines falling off and destroying a cylinder, so be very sure your oil lines are ALL connected as they should be.
Memory from the OLD site where the hell is the steve price tips section when you need it.
 

4x15mph

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I agree by the color and location that it is probably the intermediate bearing grease from the zerk. You still want to check all oil lines
 

RobT

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Check for bad hoses or clamps on your exhaust , the exhaust has oil in it and when a hoses leak or the water box wears a hole in it etc the exhaust and water with oil will get in the hull. The oil will look dark or black from the carbon during the combustion process, also the engine may feel a bit sluggish since it is pulling in exhaust gases from the leak. Also those were NOTORIOUS for the oil injection lines falling off and destroying a cylinder, so be very sure your oil lines are ALL connected as they should be.
Memory from the OLD site where the hell is the steve price tips section when you need it.
The leak in the second chanel is same as you described above. I'll check for bad hoses or clamps. Thank you
 

RobT

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How long has the boat been sitting? The blue looks like it could be marine grease from the seal or coupler. But it would have to have been sitting a while for it to liquefy like that.

Only other oil would be the pre-mix. Does it match the color of oil you're using?
I've took the boat out around 5 times this year. I own this boat for about over an year and I've never greased the bearings so it could be liquified marine grease. I'll put some grease this weekend and will see. Thank you
 

RobT

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How long has the boat been sitting? The blue looks like it could be marine grease from the seal or coupler. But it would have to have been sitting a while for it to liquefy like that.

Only other oil would be the pre-mix. Does it match the color of oil you're using?
I use yamalube which has like dark purple color
 

bluejay1977

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I use yamalube which has like dark purple color
Hey, Just wondering if you every found the source of the leak? I have some oil leaking in the rear channel as well; looks like yamalube. Can't find the source. Any help would be greatly appreciated guys :)
 

RobT

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Sorry I wasn't able to find the source of the leak. The blue leak looks like liquefied Yamaha blue marine grease and the dark is yamalube. It is coming out from under the engine but I can't tell from where. I checked the hoses and everything look ok...
 

itsdgm

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Welcome aboard @bluejay1977. I'm assuming that you came here to find help in locating your leak. I don't have any Yamaha 2 stroke experience. But in my sea Doo, I had similar puddles of oil. I ended up replacing all of my oil lines (from tank to oil injector pumps and from pumps to carb). From what I've read, Yamaha oil lines were suceptable to shrinkage and would pull off and burn up cylinders. So that's where I'd start looking for leaks first. But I'm sure guys with more accurate Yamaha 2 stroke advice will chime in shortly.
 

bluejay1977

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Welcome aboard @bluejay1977. I'm assuming that you came here to find help in locating your leak. I don't have any Yamaha 2 stroke experience. But in my sea Doo, I had similar puddles of oil. I ended up replacing all of my oil lines (from tank to oil injector pumps and from pumps to carb). From what I've read, Yamaha oil lines were suceptable to shrinkage and would pull off and burn up cylinders. So that's where I'd start looking for leaks first. But I'm sure guys with more accurate Yamaha 2 stroke advice will chime in shortly.
I really appreciate the quick reply :). Thanks so much. It looks like the last owner actually had the clamps replaced on the lines from the oil pump. Everything looks secure. I traced the lines all the way from the oil tank to the filters, to the pump and up to in injectors; doesnt seem to be any leaks along the lines. Its strange.
 

bluejay1977

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Welcome aboard @bluejay1977. I'm assuming that you came here to find help in locating your leak. I don't have any Yamaha 2 stroke experience. But in my sea Doo, I had similar puddles of oil. I ended up replacing all of my oil lines (from tank to oil injector pumps and from pumps to carb). From what I've read, Yamaha oil lines were suceptable to shrinkage and would pull off and burn up cylinders. So that's where I'd start looking for leaks first. But I'm sure guys with more accurate Yamaha 2 stroke advice will chime in shortly.
Sorry I wasn't able to find the source of the leak. The blue leak looks like liquefied Yamaha blue marine grease and the dark is yamalube. It is coming out from under the engine but I can't tell from where. I checked the hoses and everything look ok...
Hey RobT, thanks for your reply. Im gonna take the carb cover off to see if I can trace the leak; I'll let you know if I find it. Also, At full throttle, Im now finding that one engine runs at 7000 rpm and the other at 6500; have you ever run into this sort of thing? Im hoping its just a high speed idle screw adjustment.
 

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@bluejay1977 , post a picture of the oil if you can. It sounds like you checked all of the oil lines which is the most important, first step.
 

bluejay1977

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Good morning Guys. Sorry I havent posted a pic of the oil leak just yet, but stay tuned and I should have one posted today. Im hoping that some of you experienced yamaha jetters will be able to help me figure this out. Cheers!
 

bluejay1977

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Hey Everybody! Guess what - I took off the flame arrestor cover, and THERE WAS NO GASKET! - I guess the last owner had it off and didnt put a new gasket on. WOW.
I am 95% sure this is why im leaking oil (anybody agree?)
My Question is this: can I use a liquid gasket to reseal? If so, do I put it above and below the shiny metal plate? Thanks Guys.
 

4x15mph

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Great find and I would agree that would cause leaking. The gaskets do go above and below the arrestor bracket (shiny metal thing). They are very inexpensive so I would order those versus using any liquid gasket material.
 
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