hillbilly24

Not necessaraly, it he ran one motor significanly longer then the other then you may not see the problem on the other one. I'm not saying that this IS the problem, I was poining out a possibility. And no I don't spell very well

OldSchool

Dock,
Did you get the "milkshake" oil out of there yet? If you haven't, you need to do that asap!!

Pantera1

Ok that actually make a little sence, i can see how that can happen ..In that case id be reving the motors while on the hose to blow the excess water out..

FloridianSon

If it were mine before the last quart of oil was drained out of the problem motor I would have allready had the engine and exhaust isolated and the block checked for holding air pressure at least 20lb. for at least 10 min.Those stock motors I still feel will run all day on or off the hose with out reversion I have a LSA of 110 and installed on a 110 and I did the valves last year only had a small amount of rust on the valve seat and run on the hose every two weeks.I would be looking at intake area Mer.service bulliten has a different tighten sequince for intake manifold on bbc because of this and I had problems that there was no thread sealer on the intake bolts that went through the block but that only gave my a small amount of water that showed up as lots of steam out of the valve cover breather.I don't think my 10lb is to much pressure at idle when the hose is at 60lb at the shop.Your talking with the boat in the water and sucking up the water yes 10 lb. would be to much as at higher rpm we would be over our let's say between 18 20lb. at WOT. I think Mer was talking about there higher perf. motors. Good point Articfriends.Not the hose in this case.

offthefront

iTrader: (1)

Here we go ... problem is .. it could be any of the Sineros mentioned ... When i got my 311 last year ..same thing happened first time out ..water in port motor ...we pulled the motor ..pulled heads ...had heads checked and valves done ...pressure tested manifolds .... never found a problem ...put it all back together and it runs great.... It does use oil like a mofo but thats another Thread ...

First thing is to get the oil out .. Cuda's half n half should do it ....oil cylinders like Hillbilly sez ... if I pulled anything it would be the risers and look for any signs of water running back towards motor .. also compression test the motor ...but you need to have the water out and not have just oiled the cylinders ...that gives funky readings ... how old are the EM's and risers ? If they have 400 hours ..they prob should be changed out ...but in the photos they look pretty good ..outside ...cant tell inside but usually if you see any signs of water on the outside at the risers and minifold joints its time ...

dockrocker

The manifolds and risers look fine on the outside - no signs of water or rust anywhere. They definitely the originals, there is no indication that a wrench has ever been on them since they left the factory in OK.

I'm going to start with the risers, and if that doesn't do it I may take it to one of the local shops.

FloridianSon

Well hell I was wrong got 5-6lb.at the cooler (my son got me straight on that )and I got the pressure from the hose and it was 90 psi at my house.I feel so silly. Hay Dock I still think if you take off one therm housing hoses that leads to one manifold then take off the hose at the outher end of the outher manifold and double it back on it self and hook it to the therm housing it will make a loop and that seals off the motor.then take off the raw water hose from the therm.housing.get a pice of hose that will fit the therm housing at auto parts store and a water pressure gage and air chuck adapter and pvc fitting from home depot and just charge up your block you might be able to disallow the block with out to much tearing down first.Hope you get it fixed. James

Bill272

I was ready to hop on the "there's no way the hose pressure can cause reversion", and I still might. But in looking at your pics, it seems like your exhaust doesn't drop much at all and with the silent choice, water is probably dumped into the exhaust fairly high up close to the elbow. In your other boat pics, I noticed that you're backed into the driveway. Is there any slope there? The boat will sit a lot lower in the back in the water than it does on the trailer, and if the boat is pitched down at the bow, that only makes it worse.

I had some reversion last year from a low idle and a low pitch to my exhaust on 500's, and it dumped water probably 12 inches farther down the tailpipes than your setup.

I'd change out the oil, crank up the trailer jack, and run it for a few minutes at 1200 rpm before pulling the risers. If you see water in the exhaust manifold, it would most likely be from the riser gasket, which you'll be replacing anyway when you put it back on. If it's dry, it was probably reversion. If the oil gets milky again, then it's probably something else.

As for changing the oil, I use the big bucket with the electric pump on it. Check your drain plug to see if you have the merc oil drain system that has a hose threaded into the oil pan.

Chris288

Doc,,,,,, you never said IF you checked the oil when you bought the boat ??????? I too agree,,, you have a very shallow slope in the exhaust and the hose could have been the problem,, I would change the oil, run it at the ramp and see if you get any water..

dyno

Mike it wont hurt to change the riser gaskets for piece of mind, mine looked like brand new on the outside and they were shot! I lost a motor before I figured it out.