240 sport jet

[Merc 2.5]

I have a modified 240 sportjet converted outboard with Ridgeback mid, lately I've been getting alot of the thick milky crap inside mid even down on top lower unit , water tube is covered also. Motor seems be running good , carbs not dumping fuel but was about pull em off and check everything, firing on all 6 and not double firing , I replaced end cap with one that has good seals in it. Any ideas. It's excessive for sure

[KIRCHNER]

wow. i noticed the same thing on my ridgeback 15'' i looked in the open snout,behind the tuner,bluish/green milk coating from the plate down the mid,inside. must be from the 2pc plate. nasty lookin oil. im down 1200 rpm and have spark all six i dont think the oily mid is affecting my troubles, who knows?

[mercrazy]

bottom crank seal? Where else would unburned oil mix with water and run down inside the midsection? I guess if you had a head gasket leaking badly it could do it but it would have to kill the fire on that cylinder.

[Merc 2.5]

bottom crank seal? Where else would unburned oil mix with water and run down inside the midsection? I guess if you had a head gasket leaking badly it could do it but it would have to kill the fire on that cylinder.

Ya I've already changed head gaskets also , plugs r clean , do have 1 plug that's got just a little, I do mean a little , unburnt oil on it than the rest but it's just on the tip of porcelain, not near enough to account for the amount of sludge, the manual says to put both seals in ,Lip facing down (lower unit) prob to keep water out. Im thinking bout turning em facing opposite and see what happens. With motor idling as good as it is and firing on all 6 , (checked with timing light) and carbs not puking everywhere, makes me believe something else goin on , maybe I'm over thinking it tho

[Merc 2.5]

wow. i noticed the same thing on my ridgeback 15'' i looked in the open snout,behind the tuner,bluish/green milk coating from the plate down the mid,inside. must be from the 2pc plate. nasty lookin oil. im down 1200 rpm and have spark all six i dont think the oily mid is affecting my troubles, who knows?

Ya it worries me water gettin somewhere or leaking somewhere it shouldn't and I can't find it. I have new gaskets everywhere and cleaned plates spotless

[mercrazy]

What about the big o ring? Or worse, leaking between case halves? That’s why I put plenty of gel seal at ends of cork strips.

[LakeFever]

Rear cover?

[Merc 2.5]

Rear cover?

Exhaust divider? Has new gasket and seal

Unless its cracked , but I looked and cleaned it good b4 new gasket. No water on plugs or pistons

[Merc 2.5]

What about the big o ring? Or worse, leaking between case halves? That’s why I put plenty of gel seal at ends of cork strips.

When I assembled the motor I used plenty gel and hasn't been messed with since. The oring in end cap didn't get replaced but I did put light coat get around it also to help seal. Maybe I'll go ahead and replace it with new seals again , has anyone did opposite facing seals instead facing the same way?

[KIRCHNER]

the lip faces the liquid you want to keep out,

[LakeFever]

Cracked block? Winterization issue when it was still and inboard perhaps?

[Merc 2.5]

So for ****s and giggles I put my old plugs back in (new plugs bought beginning of season) went and ran it just little bit ago and what u know , no milky crap in mid , everywhere it would have been is dry as a popcorn fart. No unburnt oil anywhere around tuner and icing on the cake is , picked up rpm also. Who'd a thunk it.

[FUJIMO]

...please explain...

[skialot2]

You changed spark plugs and milky oil disappeared? And you picked up RPM? Were the spark plugs loose and you sucked in water every time you came off plane? LOL Just kidding. You must have had a misfiring cylinder. Probably ran on all 6 at low RPM but misfired at high RPM so you can barely notice it. The unburnt fuel/oil caused the milkyness. You fixed the misfire so the milkyness is gone. Got a spark plug tester? They are really cheap.

100-240V Dual Hole Automotive Spark Plug Tester Diagnostic Ignition Test Device | eBay

[Merc 2.5]

...please explain...

Been chasing down milky crap in mid , excessive amount, seals ect, motor showed fire on all 6 , i indexed the motor setting timing with timing light,
And I checked for double fire , all good , since plugs were new i never could get a good plug read with them , from the time u started this thread up til yesterday, all I did was change plugs , ran it yesterday there's no milky oil in mid and no unburnt oil around tuner. Easy to see with offshore mid. That's the only thing changed. So obviously the plugs wasn't burning hot enough to burn off the fuel or a misfire , but I would of noticed a mis fire or a cyl dropping