If nothing is obvious it makes me wonder if you possibly have a reed problem with fuel being pushed out of the intake at high speed.
If it is a leak from the high pressure side of the fuel system I would think you would see it at idle because the pressure should be the same regardless of rpms.
Don most likely has seen this type of problem before and can give you a starting point.
Is the engine still oil injected, or running PREMIX (oil pump and system removed)?Originally Posted by Chadrap
Any area more "concentrated" than others? I would be rechecking your fuel pressure (and all fuel SUPPLY LINES) for leaks.
Would also be looking very critically at VST overflow possibility- as it will dump (vented/excess) fuel behind intake.
I would give this TOP PRIORITY- as Leaking fuel is a Fire and Explosion Hazard!
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
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I'm running double oil right now. Injection plus 50:1 in the gas. There appears to be plenty of oil mixed in with the gas that's collected in the lower cowl, so Im thinking the leak may be after the vapor seperator and high pressure fuel pump. I'll start going through my hoses and such tonight. I doubt its the reeds, I didnt take them off the plate, I installed carsons a year ago and theyve been working great. This past rebuild i never removed them from the plate. Could it possibly be a gasket under the VST airbox and reed blocks? I doubt its an injector problem but what do I know.
I feel certain that this will be an easy fix.
Thanks,p
Chad
as I was cleaning up the mess I looked down at my cowl and saw probably the best clue possible.. should be enough for an experienced tech to get an idea.. now I'm thinking maybe the intake like Ba$$in suggested.. notice two predominant areas of oil spray and obviously the flywheel got a good shot at some point..
after I posted that picture I can see that its more obscure on the computer than it looks on the phone. So in case you cant tell, there's clearly fuel/oil being slung off of the flywheel from the 1-2 o clock position (looking down from top of flywheel). And another spot at 9 o clock where fuel and oil was sprayed onto the inside of cowl.
I think I just found my answer. I removed oil cap from under cowl reservoir.. put it back on and tightened it. The top broke off of it like a pringles can. I bet it was cracked and the pressure from the air vacuum was forcing a spray of oil through a small orifice in the cap all inside the cowl. easy enough!
I would replace the cap/sensor, cleanup the mess with degreaser, bleed air from engine-mounted tank, and then monitor for further leakage.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Be carefeul with the new cap. I think Merc missed the mark on this one. It is strong everywhere except when the top meets the sides and it will split if you really tighten it. The top needs to be as thick as the sides of the cap and that would have made it a lot more durable. Unfortunately not going to happen.
Snug the cap to prevent leaking. It's not something that requires any excessive amount of force (it is, afterall, plastic).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
$70 for the cap?? Ha!Snug the cap to prevent leaking. It's not something that requires any excessive amount of force (it is, afterall, plastic).
I told you to be careful with it. Actually it is a cap and oil level sensor but I bet Merc sells several of them because of how poorly they are designed. Plastic isn't the problem it how thin they molded the top of the cap. Take a look at your broken one and you will see what I mean.
I see exactly what you mean. I never torqued it down really tight. I'm sure 14+ years of heat inside the engine compartment didn't help either. I have only ever really took it loose a few times over the life of the motor. I think I can find a temporary replacement with acme threads that fits and won't break but then I won't have my oil alarm. So i'll have to pony up at some point!
Bite the bullet when you can and get the cap to keep the alarm capability.
That would be my recommendation... only I'd recommend doing it before running the engine again, so that your low oil level alarm functions properly.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Certainly seals up the leak... but "Uncle Josh" (and his nephew "Tie") won't be able to let you know if the oil tank level becomes low.
That was definitely thinking outside the "tank", though (you gotta do what's necessary to get back in when something like that happens on the water).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
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