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Aargh... Milkshake Engine Oil... WTF? (Port Engine, 2016 AR240, ~300 hrs)

The fact it occurred during normal operation this time with no surfing involved is encouraging in that regard. Best of luck as you proceed. ?
The fact that it occurred during normal operation doesn’t rule out that the root cause of the problem can be surfing conditions. We won’t know until we know the problem and then if possible the root cause. Crossing fingers for an easy fix.
 
I feel your pain as I was without my boat for the month of August. Just my opinion but if I had brought my boat to the dealer and they didn’t diagnose, reproduce and fix the real issue prior to returning the boat to me I’d make sure they do any subsequent in water test drives and confirm the fix. One mulligan is all they get IMHO.
 
@Patriot I think Swatski is in real good terms with the dealer. They have history that goes back.
So James Bond doing his own testing is good as he is the one with a license to kill.
 
I feel your pain as I was without my boat for the month of August. Just my opinion but if I had brought my boat to the dealer and they didn’t diagnose, reproduce and fix the real issue prior to returning the boat to me I’d make sure they do any subsequent in water test drives and confirm the fix. One mulligan is all they get IMHO.
Well, we are in the midwest with water access a bit more limited, for example the closest ramp to the dealer is about half hour drive, and those ramps are not always operable especially this year with all the flooding we've had here. When I showed up two weeks ago they’ve pushed me to the front of the line to flush my milky oil engine, even though they're swamped with winterizing so no complains.
We also figured with the leak down and compression testing negative, hoping for the best, I kind of took it upon myself to water test just to speed up the process, and kind of glad I did. I have pretty much full confidence in the SCBM so far, these guys are strait shooters.

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Straight shooter and taking things upon yourself. James Bond stuff for real ......
 
A compression test and leakdown test is only going to verify the integrity of the compression top end. It wont check the bottem end under the pistons or the oil passages.

Been thinking of this dilemma since you first reported it @swatski and scratching my head all i can come up with is this:

If an oil cooler cracked internally it would blead water into the oil circulation system.

If a head gasket failed it would have to be from a cooling jacket into an oil passage or return.

Oil does not travel through the exhaust manifold so you can rule out a cracked
Manifold.

Remember water pressure is much greater when the jetpump is creating it, so my 1st guess still is a failed oil cooler because on a hose it might not create enough pressure to push the water through a small crack.
And i believe there is a direct cooling line to the oil cooler. And the engine block used a thermostat and slower moving water flow. Separate i believe, would have to consult my manual to be sure.

If in fact its just the oil cooler, not a big deal and the engine is still good.
Got my fingers crossed for u
 
A compression test and leakdown test is only going to verify the integrity of the compression top end. It wont check the bottem end under the pistons or the oil passages.

Been thinking of this dilemma since you first reported it @swatski and scratching my head all i can come up with is this:

If an oil cooler cracked internally it would blead water into the oil circulation system.

If a head gasket failed it would have to be from a cooling jacket into an oil passage or return.

Oil does not travel through the exhaust manifold so you can rule out a cracked
Manifold.

Remember water pressure is much greater when the jetpump is creating it, so my 1st guess still is a failed oil cooler because on a hose it might not create enough pressure to push the water through a small crack.
And i believe there is a direct cooling line to the oil cooler. And the engine block used a thermostat and slower moving water flow. Separate i believe, would have to consult my manual to be sure.

If in fact its just the oil cooler, not a big deal and the engine is still good.
Got my fingers crossed for u
Super helpful, thank you. Much appreciated!
I believe Pat of the SCBM will be checking the oil cooler - I think he did say something about taking it off at this point and pressurizing as one of the next steps. I will follow up next week, but I obviously don’t want to be telling those guys what to do. This is something I believe is on their radar though.

This also lines up with what @buckbuck, and separately @Cobra Jet Steering LLC, suggested - pointing out to the oil cooler dedicated water line.

 
Straight shooter and taking things upon yourself. James Bond stuff for real ......
Man, this is not your balmy warm Texas my friend, we have real winters here, lolol. Not many boats on the river this time of year...

 
Oil does not travel through the exhaust manifold so you can rule out a cracked
Manifold.

Oil dos not travel through the exhaust manifold but it has been confirmed with multiple MR1 motors that with a breach water gets in the oil it can not be ruled out. When there is a breach in the water jacket It gets into the cylinder then makes its way past the rings and into the oil I’m not sure how it does not hydrolock most of the water must be held back by the exhaust being expelled . The symptoms seem very familiar to my friends boat . When it was run on the hose there was no problem but the water test turned up milky oil .The manifold was removed and it had a breach replaced with a good one and no more milky oil.


@swatski can you check the dipstick oil level to see how much higher the oil is ?

So when the dealer swaps the oil again if you could get one of the Flir thermal imaging tools it would be a great way to possibly pin point that hot spot if it’s even possible. This would be a great way to trouble shoot if it’s identified and confirmed with visual inspection after the manifold was removed. Typical marine motors need manifolds changed as regular maintenance .
 
@Cambo and @swatski I went back through the infrared pictures of my MR-1 engines while looking at exhaust manifolds where they bolt to the head. In every instance they appeared to be running cooler than the head of the engine. Probably due to efficient cooling. Perhaps a breach would show a hot spot but I just don't know.

I think it might be worth while taking an oil sample and sending to Blackstone. I believe they will be able to see if there is any excessive metal wear. They may be able to aid in diagnosing with their findings.
 
Straight shooter and taking things upon yourself. James Bond stuff for real ......
If this thread elicits for more James Bond references, I'm all in. Grew up in the Roger Moore era. A thread for another time is who's your favorite Bond :-).
 
I always felt the Bond movies were overrated. Please don't shoot me!:D
 
Perhaps a breach would show a hot spot but I just don't know.

Two reasons why I keep pushing for this to be checked

The hole is as large as a pisser port and 99% of that hole is exhaust gasses running in the water jacket 1% water making it into the cylinder . This has to be the case because it would not take more than a few ounces to cause hydrolock and the flow rate of the pissers is extremely high.

In every picture of the breached manifold you can see black carbon in the water jacket and it should be abnormally hot in the area of the breach especially if run on the hose .

this would just be very helpful to troubleshoot since you are having the problem and if it could be identified and help in the future if anyone else experiences this Issue.
 
I am starting to get @Betik 's references to Bond. I can see the similarities...I am a Sean Connery Bond guy. From Russia with Love (1963)

20191207_090143.jpg compared to 20191207_090616.jpg From Missouri with Love (2019) IDK, what do you think.
 
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So when the dealer swaps the oil again if you could get one of the Flir thermal imaging tools it would be a great way to possibly pin point that hot spot if it’s even possible. This would be a great way to trouble shoot if it’s identified and confirmed with visual inspection after the manifold was removed. Typical marine motors need manifolds changed as regular maintenance .
This is certainly possible I keep thinking though @fairpilot boat showed that kind of damage after 10+ years in salt water, I agree with you this would be the first place to look if not for the fact the boat is 3.5 yo, fresh water, and lives on a lift.

@swatski can you check the dipstick oil level to see how much higher the oil is ?
It is impossible to tell, the foam smears the dipstick, even after it would normally have settled down the foam seems to cover everything on the inside including the dipstick tube. We (Pat and I) crawled over the engine compartment after the last ride, thinking the oil would settle down and we can see the level, however foaming makes reliable volume determination virtually impossible. Not saying it can not be done, it just isn't easy or practical, under the circumstances.
I felt kind of stupid when they asked me that very question (when I first brought the boat in with the problem) and I didn't know the answer... Well, now they had a chance to ask and answer that same question on Thursday when I returned with the boat after the water trial, and the answer was: it foams, it's looks like water intrusion, let's suck this mess out of the engine ASAP. The foam does not seem to be settling down fast and it just covers/smears everything.

EDIT: BTW - one idea was that maybe the OEM dino oil does not foam as much as amsil, etc., well yamaha oil foams just fine.


I think it might be worth while taking an oil sample and sending to Blackstone. I believe they will be able to see if there is any excessive metal wear. They may be able to aid in diagnosing with their findings.
This came up as well, and they tried to collect the compromised oil in a separate container for that purpose, but as they were having hard time to flush it clean they started using various oils and mixed in some diesel etc. get the water completely out before flushing with new oil.
He said he did look for any particulate material or metal particles that apparently are not that difficult to detect. Hard to tell, but I think this ship has sailed. If and when we get to the bottom of the current predicament I will certainly like to send the oil off of the next changes (from both engines) to compare.


Two reasons why I keep pushing for this to be checked

The hole is as large as a pisser port and 99% of that hole is exhaust gasses running in the water jacket 1% water making it into the cylinder . This has to be the case because it would not take more than a few ounces to cause hydrolock and the flow rate of the pissers is extremely high.

In every picture of the breached manifold you can see black carbon in the water jacket and it should be abnormally hot in the area of the breach especially if run on the hose .

this would just be very helpful to troubleshoot since you are having the problem and if it could be identified and help in the future if anyone else experiences this Issue.
I agree. If the oil cooler is intact the exhaust manifold and the cylinder head would be next items on the differential (diagnosis).
Wherever the water enters from must had started burning foamed up oil as soon as it foamed up and started getting sucked back in the intake manifold through the breather tube. I think.

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Water to oil heat exchangers/ oil coolers are known to fail when they have air pockets on the water side because they corrode where they are wet but not submerged I think this is likely your culprit best of luck
 
Following closely, sending good vibes for least painful outcomes.

Note, per Magnusson-Moss Warranty Act and a ton of case law, the OEM engine oil cannot be mandated as a condition for warranty coverage. The OEM can mandate an engine oil of equivalent specifications, however. In the US, the API specs are generally accepted as the standard and Yamaha does call out the API specs in their owners manual (as does every engine manufacturer I've ever owned including small engines for lawn and garden use, etc.)

Importantly, if they use "improper oil" as reason to void a warranty claim, "the onus would be on (Yamaha) to prove that a non-manufacturer oil damaged the engine." Reference (there are plenty of others out there): Do I Have To Use the Manufacturer's Oil? | Edmunds

Proving the oil caused the damage (keyword: caused) would be exceptionally difficult, of course.

I am not suggesting the oil was at fault, I have no idea, but I have seen the oil manufacturer pop up in this thread a couple times and had not seen anyone point these Magnusson-Moss Warranty Act facts out here. Note also that @CobraJetSteeringLLC has a bunch of knowledge and practical experience in this general subject from his aftermarket business.
 
As far as warranty, I'd obviously want to wait and see what failed, first. I think it would be difficult to pin any fault on Amsoil use vs Yamalube, I just don't see it.

That said, knowing what I know now, I would 100% subscribe to the Yamalube warranty program @BigAbe75 and @haknslash mentioned, no question.

I do not recall that extra warranty being available at the time I purchased and I probably wouldn't had bought it at the time thinking those engines are "bulletproof". But in retrospect - it seems a complete "no brainer" for any new boat buyer/owner. At least the way I read the rules of the program I would have had nothing to worry about right now. Too bad!

Coming from Yamalube, not Yamaha, it is also kind of double on the warranty insurance (nice) and the coverage seems pretty extensive and up to 5,000 hours (for our boats) which few owners would ever reach leave alone exceed:
https://yamalubeadvantage.com

EDIT: well, damage due to freezing, overheat, or fluid contamination (e.g. with water in oil) is EXCLUDED from coverage; so - there is that, lol.

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Sorry to see the mystery continues. However it did look beautiful on the river for your test run.
 
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