oops not to fast I purged the heat exchanger using the extended season pump like I said in the previous thread but then realized the anti freeze could have come from any where in the raw water area.I thought it only purged the heat exchanger then read it purges the whole system is this correct?Again the oil level is the same and I took out the first two plugs one from each bank cranked it two times all is fine in those cylinders.

Well normaly if every thing was working right the blue pump would only drain the raw water side of things and not the closed cooling side of things [Anti-Freeze] But if you have a crack some place or a head gasket, Ect, Then yes you could get both water and anti-freeze coming out when you use the blue pump. You should try what ray said for starting point, Because you may not see the water or anti-Freeze on the dip stick because it could all be at the bottom of the oil pan and not mixed in with the oil yet, And if you can't pull the oil and want to try to see it on the dip stick then you could try blowing strong air down the dip stick to see if you get a diffrent color oil with out running the engine, Also you could try pulling off the oil filter just to see what it looks like to. Good luck to you with it.

I did what Ray had said I did drain the oil just oil Question if the tubes inside the oil cooler did have a crack wouldn't that fill the heat exchanger so when I use the blue pump anti freeze would come out.I also refilled the resivoir with antifreeze an its been sitting for 4 hours it went down 1\3

There are only so many places it can go and you've eliminated 2 of them. Its leaking internally between the closed cooling system and fresh water side. Most likely its in the heat exchanger. The only way to know for sure is to isolate it and pressure test it alone.

1. By chance, is your boat parked on an incline of any degree other than perfectly flat? If so, is the bow of the boat pointing slightly down hill as most boats do when parked in non-custom driveways.

2. Where ever you have it parked, is it going "down hill" on the trailer? Reason - If you have a leak coming from the weep hole or something, lots of boats are shaped so that what ever falls in the bilge will run forward until the boat is moved... Stranger things have happened.

3. Exactly how are you winterizing?

4. You said you only pulled out a couple of plugs - one from each bank.. If you suspect water leaking from a head gasket, you need to check all eight. Crank it over with ALL plugs taken out PRIOR to cranking.

Get yourself an telescoping mirror similar to the Snap-On UIM325 and a flashlight. Check both of the press in seals at either end of the exchanger directly underneath it. Also, get a shot of the smaller hose connection directly under the center of the crossover that goes to the circ pump. This is a very short hose that is just long enough to have a hose clamp on it (it's actually a seal and not a hose...). I suggested the mirror and flashlight if you don't have good easy access to the front of the engine. So far, that's a total of four places to check including all 8 plug holes.

I highly, highly doubt it's a failed heat exchanger.

With all due respect, anyone is CRAZY to rely on that lame raw water pump out system. It is NOT adequate for cold freezes. It leaves a lot of water in the system. I don't care what the Merc Manual says on that one.. Test it yourself by pulling off some of the lowest hoses after you use the blue pump. You'll see what I mean.

What he said is very true! just spin the lower petcock on the impeller housing and that will tell you how well the bicycle pump works!!!

I completely removed the water dump system on mine and threw that blue bicycle pump in the trash. Also made the engine a lot cleaner and much more simple plumbing...

I still have mine for resale value, but you also have a Raylar setup if my memory is right? What speeds/rpm are you running? Was it worth the loot? You have to be in the 80's right? Sorry for thread jacking op...

the boat is in my barn cocrete floor boat is complely level.how I winterize change oil flush system run it for twenty mins add four stroke oil to the fuel filter while its still warm I flush the system with purple antifrezze approx 6 gallons then I use the blue pump and evac the system and open all the blue plugs,I will pull all the plugs this am.But one question what does it mean if the cyls are dry would it still be a head gasket.I will also take the heat exchanger off and test.Note I make sure that the orange antifrezze is topped off in the closed system

ok just pulled all the plugs no anti freeze so I put 18 pounds of preasure in the res no anti freeze in the cyl or the pan not much if any came out of the purge system I closed the purge system and will wait a couple hours.Ok I am back on stresss medication!!!!!!!!!!1