Got Milk?....yes I got Milk!
 

O.K here we go... I know we have beat this subject to death but here we go again. I've got water in my oil.....at first I thought it was a oil temp problem(condensation) it was in both motors, I changed thermastats and ran it another weekend...the water has warmed up alot! from low 50's to now in the mid 60's...well one of them cleaned up great but one has some serious milkage going on...its coming out the breathers...well after doing some searching on the subject I've come to the conclusion that it must be one of three things, the first and worst....head gasket,or second intake gasket...or maybe its what Tinkerboater posted a while back about an exhaust diverter problem...I have noticed that when the silent choice is engaged its abnormally loud...I thought it was just hanging up and was'nt closing completely could that put water in the oil? well what do you guys think? I know that I have to start with a compression test and go from there but I thought I would ask you guys for your input first....I've got all next week off guess what I'm doing??????
Don

Check your exhaust springs ... That's what got mine!

A compression test would be helpful, but I'd really like to see the numbers from a leak down test. I've seen engines with fair compression have terrible leakdown.

Have you check your exhaust for reversion? Before tearing your motors apart, I'd start by making sure you are not getting any reversion. And if you are getting enough reversion to milk your oil (which is possible) then, I'd seriously consider R&Ring the exhaust valves before one drops.

well its a new motor last year.....only aboy 60hrs on it dont really think the exhaust springs are going away yet but anything is possible...as for reversion well thats what would be happening if my exhaust Y pipe was blocked by the flapper right? Well thats happened to me before(reversion) but it dosent act like that....runs great!

Guess I was wondering if there was a gasket that could be leaking? ie riser gasket or a cracked tube.

new exhaust last year at rebuild....Emi's hope it aint them....

TTT, anyone else have any input? damn this thing has me all worked up ,havent slept since 3:00 am. How does a leak down work Cord? can I do it myself or do I need to pay someone?

go to http://www.sterndrives.com/ go to the mercruiser service bulletins link and then to the bulletins link on the next page. There are a couple that deal with water in both the oil and in the engine, they are pretty detailed and they also tell you what to do to diagnose various problems.

If you are sure that it isn't reversion, and I doubt it is, and the manifolds and risers are in good shape, my number one suspect would be the intake manifold.

I talked to TinkerBoater last night and he told me to pressurise my cooling to around 15lbs and see if it leaks down ......anyone ever done this?

I had a motor that keep leaking water at the intake manifold. After about 3 or 4 tries I changed to a differnt type intake gasket. Then keep tightening up the intake manifold. I was using a torque wrench & was amazed how many times I had to retorque ( 3 or 4) before they were would not loosen up.

Dyno, you'll need a compressor and a special leak down tool. This is basically a regulator and two gauges. The good ones will actually show the percentage of leakage. The cheap ones will have pressure numbers and make you do the math. You pull out one spark plug hole and turn the engine so it's at TDC with both valves closed. If you don't have the engine at TDC it will try to rotate when the cylinder is pressurized. That's why the other plugs are being left in. When you pressurize the cylinder, try to listen to the carb or exhaust. If you hear air escaping from either you know that a valve isn't sealing. Could be a burned valve, bent valve, damaged seat, or the valve isn't closed. If the air is leaking past the rings, shoot some light oil into the cylinder. Then retest. If the test improved, then you know that the rings are leaking. On a car, you can check the radiator for bubbles which would indicate a head gasket.

Thanks Tim!!!!!

Don't get too hung up with the numbers. This test will reveal things that never knew about your engine (and proably don't want to know). I believe less than 10% leakage would be for a new engine. 20-30% for a well worn healthy engine. Over that you have something happening. :mad: Anyways, look for cosistency between the cylinders.

Let me give you an example. On my old 500hour 454 that sank last year, I was loosing some speed. I had drop at least 4mph off my top end. Was baffling me, because the motor still sounded and felt strong. We did a leak down test and found that most of the cylinders tested in the 20% range. Really good for a old engine. I had one cylinder that tested at 40% and a final one at over 60%! On that one cylinder the air could be clearly heard escaping past the intake valve.

When Bruce tore the motor down, he was amazed by the condition of the motor. I guess the intake valve was burned and some rings were broken, but other than that it was in good rebuildable condition. Too be honest, the credit for the engines condition should go to the prior owner. I proably did more to wreck it in 2 years than he did in the prior 10.

Cord if the intake gasket is bad will it show up???and how ???can you hear it? Summit has a kit for $65 but I think I can make one up with some stuff I have laying around...

No, it wouldn't show up. You could try the old trick of starting the engine and passing a unlit propane torch over the gasket. If the rpms pickup, you've found a vacuum leak. Of course, the gasket could still be bad between the cross over and the port. I wonder if, the leak down tester could also be configured to test your water jacket. If you plugged the water outlet and inlet and could hook up a air line to one of the plugs, you then see if you have a leak.

Thats what Tinker told me to do .....I've scammed enough fittings gauges and a schrader valve to make a tester but still need to figure out how to cap off the water inlet and the two outlets at the exhaust.....Tinker told me to make a big loop from one outlet to the other, sounds good.... but the large inlet could be a trick!
Don

Good idea on plugging up all the stuff Cord that should help a lot I would think. As long as the leak is not the head gasket.

Jon

Head gasket should show up real easy with the above tests.

Intake gasket I had leaking I was only able to tell when I tore down & checked gaskets. I did not pressurize the water & check that way.

anything else I can check???

Some hardware stores have large rubber stoppers. You could try inserting one of those into the hose and clamping it. Plumbing supply houses also have a stopper that's inserted into a drain and inflated. Plumbers use these when the pressure test waste piping.

well all I need is to stop out at my Dads to get a regulator and I think I have everything I need to make a leak down kit.....I'll stop at the local super Hardware store to see about plugs for the hoses thanks for your help Cord!
Don

ttt

Just buy a cheap pvc plug that fits the hose and clamp it tight. Do the preasure test with the engine hot. IF the engine doesn't hold air presure than the leak is in the water system somewhere. You wont find the water leak doing a pressure test of the valves and rings by doing a leak down test. Just pump the cooling system up to 15 psi and get some soap solution and spray it around the gaskets and hose connections to look for external leaks- if none are found then the leak is internal and start taking the engine apart. If the leak is internal then pull the spark plugs and first listen for the leaking sound at each plug hole. For the smaller hoses just loop one over to the other side of the thermostat housing. Clamp them tight. GOOD LUCK
If you need me to come look at it just call me.
STEVE W.

well the motor went away........well the oil pressure did was still running fine. Changed the oil again.... ran it to pentwater with Jafo and when I pulled back on the sticks the pressure droped below 20....game over as Crazyhorse would say, Pulled it out last night and got it on the stand, havent opened it up yet so wish me luck!!!!!

Good luck Dyno.....I bet it's nothing too serious, at least I hope....keep us posted,....Fred

Hey Fred!! glad to see your still kicken after your long vacation... I think its the intake manifold...but I'll need to replace the mains too minimum....hope for the best! are you going up to GreatLakes this weekend? I have one more weekend at the cottage I'll stop to see you! Hey you can use my spot in the rack if you like...Clear it with John its ok with me....I'll be out for a while!
Don

I don't know if I'll make it up there or not this weekend Don...some things at home I should do.....but they may have to wait!!! It is air show weekend isn't it?....I hope its just your intake and a change of bearings....will the cam bearings need replacing also or ??? Thanks for the rack offer but I'm ok with just being on the trailer in building #2, plus I always drive my crew-cab dually up there anyway and it loves pulling, although it isn't very far to the launch ramp from the marina, do you think you will be back running soon?.........Fred

Let me know if you need a hand Dyno. I'm getting pretty good at this re-build thing!!! :mad:

Also, I've got ONE good, unused gen 5 head gasket if that is all you need. You're welcome to it.

Mike

Thanks Mike I'll let you know!!!