Port engine milky oil 2006 AR210 MR1

[CaptRedbeard]

Purchased boat this spring. Changed oil and filters in April. Old oil was not milky. We’ve put probably 20ish hours on it this summer - it has been running great. We’re just wrapping up a week on the lake and I noticed the port engine was only getting up to 7300-7500 at WOT. Starboard engine will rev to 8800-8900 (which might be a separate issue).

I checked oil and starboard engine is fine but port engine is milky but at the proper level. I pulled spark plugs and they’re a bit black, with the cylinder 3 plug being the blackest and having a moist substance on the threads/plug tip.

Is the boat okay to cruise around the lake in its current situation?

Looking for recommendations on order of things to check. I’ll be checking compression as soon as I get home to my garage this weekend.

 

[Dave burke]

It’s hard to tell from the pic but the oil doesn’t know look milky to me. Is the color more brown or white?

If it’s really milky, it’s pretty white looking and I would not be running it if that’s the case since it means there’s water in the oil and it won’t work properly.

 

[CaptRedbeard]

It’s hard to tell from the pic but the oil doesn’t know look milky to me. Is the color more brown or white?

If it’s really milky, it’s pretty white looking and I would not be running it if that’s the case since it means there’s water in the oil and it won’t work properly.

I’d say it’s more brown than white. Here’s a pic of both dipsticks side by side.

Another note is that I’ve noticed a bit of a “hesitation” or slight drop in rpms at WOT on the port motor.

 

[ToddW850]

Dang. I just changed out my plugs from last year and they didn't look near what yours look like. Matter of fact, I kept 4 as spares they looked so good. Anyway, I'm guessing your lower RPMS could be due to the status of the spark plugs? And I zoomed in on your plugs and looks like there is water in the threads of Plug #3.

 

[Dave burke]

Based on your additional pic, I don’t think the oil is milky. But the plugs definitely look fouled. How old were they when you changed them?

I’d be tempted to pull the plugs on the hood engine to see if there’s a difference.

I really don’t know what the most substance could be. If it’s water, you should have milky oil. Could it be gas? Maybe oil or fogging oil. Usually fouled plugs are caused by too rich a mixture I believe (but I’m not an expert so hopefully you’ll hear from some mechanics).

Other idea is to try new plugs in both engines. I read your thread again and it seems like you didn’t change them so I definitely would.

 

[CaptRedbeard]

I definitely saw something wet (I assumed water) on plug #3. I didn’t mention that I changed all 8 plugs when the oil was changed in April.

Is the consensus that there is water intrusion in the combustion chamber of cyl #3?

I plan on testing compression and changing oil/plugs when I get back to my garage and can gather the parts.

 

[Dave burke]

I’d be surprised since your oil is not milky. But best way to check is probably a compression test

 

[CaptRedbeard]

I’d be surprised since your oil is not milky. But best way to check is probably a compression test

Oil is definitely more of a gray color than the tan of milky oil when looking at them side by side. Anybody have any idea what that might be from?

 

[cybuch]

Im sorry, but that does look milky to me. Same thing happened to one of my MR1 motors, my oil looked the same. Do a crackle test on the oil.

 

[scokill]

Im sorry, but that does look milky to me. Same thing happened to one of my MR1 motors, my oil looked the same. Do a crackle test on the oil.

I agree that it looks milky. I would bet that a plug change cures the rpm drop, but I would change the oil a couple of times until it's clear and start from that baseline to determine if milky. My oil goes from clear to slightly black with age, not brown.

 

[Cobra Jet Steering LLC]

could be bad dirty air filters making it run rich and if there is any water in the oil you will see the milk on the inside of the oil fill cap where it collected but honestly your plugs look awful but your oil looks dirty do the oil on both and the filters and the plugs and if the air filters are dirty replace them and never over fill the oil check it on a level surface and keep it between the 2 top marks always save and measure what you removed and only refill what you took out or it will ruin your air filters and when you see what they cost you will realize how important it is to avoid overfilling the oil.

 

[CaptRedbeard]

Thanks for all the tips everybody. While I am waiting for my oil change supplies to be delivered, I pulled the air filters and they do look like they had a bit of oil intrusion. It looks old but I can’t be certain that it wasn’t my doing. Regardless, they’re likely original and I should probably just replace them anyways, correct?

 

[Seadeals]

Also, the tachs are not very accurate. The ECM limits both engines to 8000 rpm, so you are likely just getting a high read on the starboard engine tach. A YDS read can show if you are logging hours above 8000. What is your top speed at WOT? As others suggested, change plugs and oil again and maybe repeat the oil change on the port after a brief idle to mix the old with new. You can also search how to drain all of the oil as some members have used the lower plug. A leak could be internal only but for good measure, take a mirror or an iPhone photo of the block from under the exhaust manifold (cylinder 3 area most common) to inspect for any evidence of a block crack. You will often see stains on the block left after the water evaporates. Here is a pic from my 2006.

 

[Cobra Jet Steering LLC]

those look homemade to me where did you find that style

 

[CaptRedbeard]

those look homemade to me where did you find that style

Not sure what you mean by “where did you find them” - they appear to be OEM. The model number is “M3” rather than the “M1” replacement that looks to have superseded it.

 

[Cobra Jet Steering LLC]

ok cool did not know they were factory . thanks I learned something new today

 

[CaptRedbeard]

Doing a little more investigation this morning and I discovered some bad news. Correct me if I’m wrong but it looks like my block is shot. First 3 photos are from my borescope and the last one is the best angle I could get under the exhaust manifold with my phone.

Edit: I just talked to my local shop and they said a swap is likely the best bet over an attempted tear down and repair of the case. I haven’t talked with SBT yet but his guess was that this would end my season. Would you guys agree on the swap based on this limited info or is there a long shot repair that might be worth it?

 

[scokill]

Doing a little more investigation this morning and I discovered some bad news. Correct me if I’m wrong but it looks like my block is shot. First 3 photos are from my borescope and the last one is the best angle I could get under the exhaust manifold with my phone.

Edit: I just talked to my local shop and they said a swap is likely the best bet over an attempted tear down and repair of the case. I haven’t talked with SBT yet but his guess was that this would end my season. Would you guys agree on the swap based on this limited info or is there a long shot repair that might be worth it?

If the blocked is cracked that is bad news. Usually it's a manifold. Personally I would look for a used, good running ski with the same engine vs SBT.

 

[CaptRedbeard]

I'll preface this by saying that I haven't verified with any mechanics that this is a catastrophic crack in my block, but I'm assuming I have both an internal and external crack. This would explain some of the bilge water I've been having, and I assume the internal crack developed recently which would explain why I didn't have milky oil when I bought the boat this spring. Please somebody correct me if I'm wrong in this assumption.

I'm whittling it down to a few options:

1- $5000-6000: find a used ski with an MR1 110 engine and swap out, then take my time on taking apart the cracked block and have it welded. Sell the ski afterwards for a similar cost. Alternatively, sell the old ski for parts for far less if I don't want to take the time to repair the old block.
2- $3000: SBT engine swap, I would have no parts leftover.
3- $500-1000: Pull my motor and dismantle it, have the block welded, then reassemble. This is assuming the block is salvageable, which I'd obviously need to verify first. No leftover parts.
4- Try some combination of an oil additive to seal the internal crack and jb weld to seal the external crack. Pray to the Norse gods of oil pressure and best case hope to get a couple of seasons out of it before it cracks again

I need another project like this like I need a hole in my head, so although its hard for me to ignore the financials I'm leaning towards the SBT route or the ski engine swap and selling for parts later.

Any/all input to help me with this decision would be much appreciated!

edit: I think this is the exact same crack location that @cybuch @itsdgm @Jon D and @Seadeals had. I'm very curious as to why this happened so I can hopefully avoid this in the future.

 

[cybuch]

I'll preface this by saying that I haven't verified with any mechanics that this is a catastrophic crack in my block, but I'm assuming I have both an internal and external crack. This would explain some of the bilge water I've been having, and I assume the internal crack developed recently which would explain why I didn't have milky oil when I bought the boat this spring. Please somebody correct me if I'm wrong in this assumption.

I'm whittling it down to a few options:

1- $5000-6000: find a used ski with an MR1 110 engine and swap out, then take my time on taking apart the cracked block and have it welded. Sell the ski afterwards for a similar cost. Alternatively, sell the old ski for parts for far less if I don't want to take the time to repair the old block.
2- $3000: SBT engine swap, I would have no parts leftover.
3- $500-1000: Pull my motor and dismantle it, have the block welded, then reassemble. This is assuming the block is salvageable, which I'd obviously need to verify first. No leftover parts.
4- Try some combination of an oil additive to seal the internal crack and jb weld to seal the external crack. Pray to the Norse gods of oil pressure and best case hope to get a couple of seasons out of it before it cracks again

I need another project like this like I need a hole in my head, so although its hard for me to ignore the financials I'm leaning towards the SBT route or the ski engine swap and selling for parts later.

Any/all input to help me with this decision would be much appreciated!

edit: I think this is the exact same crack location that @cybuch @itsdgm @Jon D and @Seadeals had. I'm very curious as to why this happened so I can hopefully avoid this in the future.

Definitely do NOT go the SBT route, junk engines from them. I am on my 3rd from them with the 2 year no fault warranty, that just expired. The engine also expired and threw a rod, so I am out 2 years, 4 motor swaps (including this one) and my $3500