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Need Help With New Used Boat Milky Oil!! Story From Day One

These metal gaskets are two compressed together.

Took black paint off to check edges.
 

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Part of diagnosing is compression testing a warm engine. If it was my boat, I would take the time to bolt it back up and test it warm.
 
I saw this build up journal of water jacket. Could that contribute to water in oil.

Other picture is cleaned up.
 

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I saw this build up journal of water jacket. Could that contribute to water in oil.

Other picture is cleaned up.
No! There are no oil passages there.
 
No! There are no oil passages there.

I know. Just if build up would contribute to water getting to cylinder? Or way of water mixing with oil due to failure of EM gasket. Just thinking of possibilities.
 
That water is blowing away from the cylinder. On my exhaust those pockets are very shallow and clog up easily. The only passage that goes inside the cylinder head is through that hole I on the bottom left of photo 162120. There are four of those.
 
UPDATE

Got EM back on and refilled oil again and its clean after running on hose twice.
I hoping it was a fluke thing from PO.

I checked compression again after it was hot I got 180 on cyl 1,2,4. I got 165 on cyl 3.
Going to check it again with EM off when I replace EM gaskets. Would there be a reason why it was higher with EM off?

Still waiting on pump parts to water test again. I wanted to post video of engine running as it idles smooth and no noise which is a great sign I guess.

Thanks all. Will report back to close thread
 
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No to EM off or on. Now would be a good time to do leak-down testing
 
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Valves would be a separate problem from milky oil. For leak-down testing, tested cylinder needs to be at TDC. Harbor freight has leak-down testers. If you have a compression tester, you can fashion a leak-down tester by removing the check valve. Set supply air at 100 PSI; If you can maintain 85PSI, that is considered acceptable. Whatever pressure, start listening for where it is escaping. Listen through a piece of plastic tubing inserted into one of the water supply holes under the exhaust port. If you hear it there, that is a good indicator that the head is leaking from the pressurized cylinder into the cooling supply. I hope some of this makes sense.
 
Valves would be a separate problem from milky oil. For leak-down testing, tested cylinder needs to be at TDC. Harbor freight has leak-down testers. If you have a compression tester, you can fashion a leak-down tester by removing the check valve. Set supply air at 100 PSI; If you can maintain 85PSI, that is considered acceptable. Whatever pressure, start listening for where it is escaping. Listen through a piece of plastic tubing inserted into one of the water supply holes under the exhaust port. If you hear it there, that is a good indicator that the head is leaking from the pressurized cylinder into the cooling supply. I hope some of this makes sense.

Would that be with EM off again, correct?

Couldn't get my hands on leak tester but followed your advice and saw video of removing shader valve on compression tester hose and listen for leaks.

I can't get true TDC as I had no way to turn engine by hand. I need two people so someone can turn drive shaft as I see the up/down of stick in SP hole. Don't have dial too either. Any tips on finding TDC?
I tried anyways and first got air from intake. Removed air supply, bumped motor over where stick just started to come up and then air was coming from exhaust. I can reproduce hearing air from EM when I got as close to TDC through EM. I tried other cylinder and would still hear air from EM using same non accurate TDC determination. So no real answer other than I didn't feel air coming from cyl head/block area.

In theory, lets says exhaust is stuck open due to poor maintenance will it not unstick with use and I should monitor it?
If it was the intake, wouldn't I have gotten contaminated oil again on the hose?
If cyl head gasket was bad would't I see water in compartment, signs of steam or contamination of oil again while it was on the hose?

Trying to use deductive reasoning to narrow possibility of low compression in cyl 3 due to stuck valve which is common in Yamaha.
Or if any possibilities of leak down above would or wouldn't contribute to oil/water mix.

I appreciate you time reading and answering my hypothesis.
 
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A flooded engine from the PO is much more likely to have caused water in your oil than any of the items you are presently investigating. Yes, all of those things are possible, but not probable. Sure, you can do a leakdown test, etc., but you need to get the water out of the engine so it does not cause damage. Your lower compression in 3 is not that low. In fact (and I don't have the numbers here to back me up), it may even be within spec still at that number.

As long as the engine is running and running well, go run it on the water and drive the rest of that moisture out. If the milky oil recurs, you can dig into it further. Otherwise, you can go enjoy your boat. Do the compression test at the end of the season or if you have something start not running right.
 
A flooded engine from the PO is much more likely to have caused water in your oil than any of the items you are presently investigating. Yes, all of those things are possible, but not probable. Sure, you can do a leakdown test, etc., but you need to get the water out of the engine so it does not cause damage. Your lower compression in 3 is not that low. In fact (and I don't have the numbers here to back me up), it may even be within spec still at that number.

As long as the engine is running and running well, go run it on the water and drive the rest of that moisture out. If the milky oil recurs, you can dig into it further. Otherwise, you can go enjoy your boat. Do the compression test at the end of the season or if you have something start not running right.

I appreciate the words of encouragement.
I feel comfortable with the number of oil changes and the time I ran it on hose the milky oil was gone.
Engine was hot too touch, let it cool down and again on hose for serval minutes.
No more milky oil. I have short video im trying to find a way to upload. The engine runs smooth, idles fine and has no rattle or bottom end clatter.

Boat ran before all the teardown began and im just waiting for pump parts to put it back together and see what it does on the water.

Im confident in what I've done is to ease my mind there's not a bigger problem.

Fingers crossed.
Waiting for parts suck!
 
Let us hope that works, but if milky oil returns, I suggest the leak-down test.
 
Let us hope that works, but if milky oil returns, I suggest the leak-down test.

I'm on it. Ordered one through amazon and it won't hurt as I am used to taking plugs in and out already. HF didnt have the cheaper version.

Any idea on finding true TDC?

Thank you again.
 
Stuck valve and milky oil are unrelated. Best time to do leak-down is with EM disconnected. You can more easily hear where air is escaping. With the spark plugs removed, if you remove the cover over the coupling connecting the engine and the jet pump, you may be able to rotate the engine with a strap wrench or by hand. I used a long 1/4 inch wood dowel and marked it at the point that I thought was TDC. On my engine, TDC for cylinder #1 is determined by alignment marks on the camshafts facing upward. Your engine may be different. It would be very helpful for you to have a service manual for your boat.
 
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Stuck valve and milky oil are unrelated. Best time to do leak-down is with EM disconnected. You can more easily hear where air is escaping. With the spark plugs removed, if you remove the cover over the coupling connecting the engine and the jet pump, you may be able to rotate the engine with a strap wrench or by hand. I used a long 1/4 inch wood dowel and marked it at the point that I thought was TDC. On my engine, TDC for cylinder #1 is determined by alignment marks on the camshafts facing upward. Your engine may be different. It would be very helpful for you to have a service manual for your boat.

I have it.
The procedure is more detailed and more things have to come off.
 
Some may disagree, but I would reuse the Head Cover 1 gasket. It seals a low pressure area. I spot adhere the gasket in place with Permatex Aviation Form-A-Gasket Liquid Sealant. It just holds gasket in place while the cover is being reinstalled. There are many sealants available. Just my opinion.
 
Update:

Got new EM gaskets, pump rebuilt, fresh oil.
Is there a difference of running it on the hose vs water? I ran it before leaving for a good 15 minutes and oil was still oil color.

After 30 min ride, I beach it and find white fluid on oil cap. Check dipstick and oil is tan but still thin. We spent 4 hrs out in the water which was great.
Boat ran like it should. Gets on plane, cruises at 30mph, turns 7000k. I got 35 at one point. The new pump bearings made it sound so much quieter.

When boat was up trailer the whole bottom and under swim platform was covered in black soot.
It got me thinking of all the fluids I poured into crack case during my previous oil transfusion. Boat was never ran hot during oil transfusion as EM were off. As good as the oil extractor is I'm sure I left some contaminated oil. It mixed with new oil and burned off the MM/Seaform during todays outing.

I stopped at Discount for crank case flush bottle (diesel and kerosene) on the way back home. Poured it in and starting flushing engine and let so called treatment work
Extracted contaminated oil and flushed again with 5gal and have clean oil running through extractor. The contaminated oil did not look like before.
It still had oil consistency but darker shade of brown and not so translucent. Almost dirty like.
Going to run it tomorrow on hose again to see if changes colors. Will change oil and filter again ready go back out Friday to test a 3rd time.

If I can't get oil issue solved is off to dealer to have head removed and pressure checked for leaks. I've read and seen the cracks by the valve due to poor casting. Hopefully they can read ECM and see if there was ever an over heat code and can give me history about boat.

Boat has 140hrs and it runs and looks great. I don't want to feel discouraged or think it something more serious. I'll keeping changing oil if it continues to run like it did and pray oil gets cleaner every outing. I just can't wait in b/w outings.

I tried to do leak down test but was getting wrong readings. After failing on [HASH=412]#3,[/HASH] I did other cyl's and got same failing result.
Finding TDC is a little more difficult than I have been trying according to service manual. I'll let the pros look at it if oil does not get clean at neat outing
 
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