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

[swatski]

Any chance the service department still has a sample of the oil they extracted? If so, I would suggest you send to Blackstone Labs to get it analyzed.

I know, right? I wasn't quick enough to think of it... Would be interesting, especially comparing the two engines as they were serviced together. I'll ask, doubt they do it routinely, but I don't know.

--

 

[Cobra Jet Steering LLC]

Maybe a dumb question but doesn't flushing the system remove any sand in the line from the pump as well as the engine / exhaust system?

The way to know if the line from the pump is blocked is pretty simple, if you do not see water exiting the pump nozzle when running on the hose then the flush water is not travel through that hose and that is the hose that supplies water to cool the engine . So just watch for water exiting the nozzles during flushing to see if the hose is clear.

 

[Sbrown]

If you dont have tow valves, or you leave them in the "flow" position during engine flushing, that should also allow a back flush action to happen between the "Y" fitting and the cooling inlet at the pump.

 

[swatski]

Maybe a dumb question but doesn't flushing the system remove any sand in the line from the pump as well as the engine / exhaust system?

I may have misunderstood the question - as stated above, water flows back through the pump intakes on the hose. So, yes, that is kind of a flush but only the intake portion of the cooling cooling system.
Water would still run down through the pump and out even if engine/exhaust passages were (partially) occluded, unless you have the tow valves closed.

--

 

[dshscarab]

Got it. Thanks for the clarification. Hopefully, your situation is something small / inexpensive. I would think the oil cooler but all it is is just a guess.

 

[swatski]

I can’t help but wonder if my extensive wake surfing use of the boat, heavily ballasted and listed, has anything to do with current situation and milky engine oil on the surf side?
(We only surf regular/port side)

Makes me wonder about two things: 1. oil distribution and 2. exhaust back pressure.

1. Oil distribution in the engine that’s heavily listed could be an issue, oil starvation would cause problems if the pickup was not getting oil to the top of the engine. Or - overfilling on one side - rear/port side - could cause the crank to make froth/aerated oil, not a good thing, less lubrication?
But, if oil starvation/distribution was the issue - I should see some failure (from surfing) on the other engine as well, no?

2. Just like there is not much water in the exhaust system of a car, our boats' exhausts are actually above the water line when on plane. That changes when the stern is ballasted/listed for wake surfing - and I plow through water at 10mph with the exhaust now pushed way down.
Adding water adds a lot more back-pressure than if it was just combustion gases, I would think, albeit clearly not to the point of killing those engines quickly but over time it could be an issue, right? There's a lot of engineering going into these exhaust systems, I'm sure those are not just routed where space allows, it’s a matched package with the engine.

In other words, if significant back pressure occurs during wake surfing operation of a heavily ballasted/listed boat - on the surf side/ballasted engine side - could that cause all kinds of problems? and the ECU would not be able to compensate for any of that as the only way to compensate for a difference in air flow would be to have a sensor in the trailing edge of the exhaust, which there is not, therefore the engine is not adjusting and only operating only to OEM pre-programmed specs. No?


EDIT:
The number 1. issue also begs the question: would I have these problems if I had the MR-1 dry sump oil system?
(Yeah, why aren’t they used on 1.8 engines? cost may be the main stumbling block? But that’s for a different conversation, lol)

I still think the other engine should show at least some of the same issues though, if oil distribution was the root cause of the milky oil here.

--

 

[4x15mph]

@swatski , another thought would be whether you were underway at any point with the engine having stalled causing water to be taken in to the engine. This or turning the engine off before turning off the flush hose. Is this possible?

Interesting point you make about the dry sump (MR1 and the newer TR1's).

 

[swatski]

@swatski , another thought would be whether you were underway at any point with the engine having stalled causing water to be taken in to the engine. This or turning the engine off before turning off the flush hose. Is this possible?

Interesting point you make about the dry sump (MR1 and the newer TR1's).

Huh, no, never on the hose on in the water above towing speeds (see below, more on surfing) - and what’s driving me crazy (and made me lean towards freezing hypothesis) - all my previous oil changes were always normal.

In other words if surfing activities were the root of cause water intrusion of the port side engine it had not been apparent during the two full surfing seasons with this boat. I’m having hard time imagining I would miss milky oil in my routine 30-50 hr oil changes.

To elaborate on the surfing and running with an engine off:

We have had instances of hard restarts of the surf side engine, this has been discussed here at great length. Many scenarios were entertained and my take away has been the most likely scenario being a sort of a vapor lock - wherein the intake manifold of the port side engine is getting really hot while the boat and engines are stoped with no cooling water running. In this regard, most convincing argument has been the cure - keeping the blowers on during those stops basically remedied the issue.

Last year I figured that while just idling the engines when switching rides is the easiest solution, it is not always possible - sometimes you need to turn them off with full ballast hanging on the swim deck. Before I figured out the blower trick, if the port engine wouldn’t start I would drop my trim tabs and get going on one engine which would always help getting the port side started - while running 5-10 mph on the strbd only. Never seen any evidence of water intrusion during any of this.

—

 

[Cobra Jet Steering LLC]

@swatski I believe the previous discussions regarding the exhaust back pressure preventing the low side engine from restarting after sitting was pretty well proven when I suggested starting the high side engine only and then turning the boat away from the low side to get it up out of the water and then starting that engine as people reported that maneuver was working .
Once the exhaust outlet on the back of the boat is sitting lower in the water than the bend in the hose exiting the muffler more water will enter the water box.
This may explain it happening only after the engine is turned off for a while thus giving the water time to infiltrate the muffler thus increasing the back pressure or a combination of the extra water and the lower position under the water since the deeper you go the heavier the pressure.
Now other things to consider is the back wash being created by the swim deck and ballast pushing down one side of the boat during the wake surfing process. All combined I doubt this is really a good thing for your low side engine especially exhaust valves and the aluminum head . If the head and valves were run hot for a time the head will usually crack around the valves and water will get in the engine oil as I said before the spark plugs are the report card on what is happening in the combustion chamber. Perhaps a modified or lower thermostat is a solution if in fact this is happening however now it's still a mystery.
And remember I know you know about the alarms and this one never gave you one etc remember I was addressing the class of 2020 every year we need to pass along words of wisdom to the new jetboaters after posting on jet boat sites for nearly 2 decades addressing the same questions when I run across something like the limp mode is NOT a SAFE mode I was saying that for the benefit of the new people or the reverse move etc so my typing sucks as I am usually thinking 3 times faster than I can type and my index fingers get really tired. But at 67 I am still out there kicking butt on the water it just takes me a little longer to get out of bed the next day.

 

[swatski]

@swatski I believe the previous discussions regarding the exhaust back pressure preventing the low side engine from restarting after sitting was pretty well proven when I suggested starting the high side engine only and then turning the boat away from the low side to get it up out of the water and then starting that engine as people reported that maneuver was working .
Once the exhaust outlet on the back of the boat is sitting lower in the water than the bend in the hose exiting the muffler more water will enter the water box.
This may explain it happening only after the engine is turned off for a while thus giving the water time to infiltrate the muffler thus increasing the back pressure or a combination of the extra water and the lower position under the water since the deeper you go the heavier the pressure.

Yes, I agree but the blower action solving (or pretty much solving) those mystery hard restarts seems to indicate cool air flow helps as well, so it could be a combination of back pressure and a quasi vapor lock (of lack of a better term) of the port side intake manifold.

--

 

[swatski]

This may explain it happening only after the engine is turned off for a while thus giving the water time to infiltrate the muffler thus increasing the back pressure or a combination of the extra water and the lower position under the water since the deeper you go the heavier the pressure.
Now other things to consider is the back wash being created by the swim deck and ballast pushing down one side of the boat during the wake surfing process. All combined I doubt this is really a good thing for your low side engine especially exhaust valves and the aluminum head . If the head and valves were run hot for a time the head will usually crack around the valves and water will get in the engine oil as I said before the spark plugs are the report card on what is happening in the combustion chamber. Perhaps a modified or lower thermostat is a solution if in fact this is happening however now it's still a mystery.

Now, this^^^ of course would be most concerning.
Basically, if the investigation indicates the above scenario has merit, that would represent a significant blow to any claims of surfability with these boats, as the long term cost becomes prohibitive. I certainly hope that is not the case!

--

 

[Cobra Jet Steering LLC]

Odd that turning on the blowers would effect anything in this situation.
Heat rises so the higher engine would be subject to the hot air more than the lower engine yet the higher one starts and the lower one won't. Even with all temperatures being even why the lower one and not both ?
You have to pay close attention to the differences between the two engines and say that the probability of the one engine habitually being hard to start must be something to do with it's position in the water and the fact that it has no issues starting when not set up for wake surfing is all the more reason that the lower position is the real issue. This is one time that I would rather be totally wrong but evidence is what it is.

 

[haknslash]

When we experienced the hard start issue surfing on Bill’s 242 we tried to crank it by turning the other way but I don’t think it helped. Ended up finally firing after cooling down a little I think. Ever since then when I would run into the issue it would be resolved by making sure the blower was on. I know it sounds strange but it does seem to help leading me to believe it could be a vapor lock issue. Anyways don’t want to derail the topic on that vs his milky oil issue. Hope you get it resolved and hopefully not an expensive fix.

 

[Cambo]

Lots of good info and so many things to speculate on hopefully there is an exact cause and effect with minimal financial impact .For the hard starting and back pressure we did have this happen while surfing I noticed two things. I had everyone switch sides in the boat to get the surf side motor up and this helped with starting. The other was to allow the boat to idle before cutting the throttle, while the boat was idling I went over to the pee holes and felt the water, after a run it would be fairly hot then it would cool down and the motor would always start up using that technique.

One big variable with surfing is the length of time someone stays up unfortunately they are all very short when we go out 30 seconds to 5 min . @swatski were you doing long runs while surfing 5, 10 maybe even 20 minutes of continues surfing with out dropping the rider ?

 

[Betik]

One big variable with surfing is the length of time someone stays up unfortunately they are all very short when we go out 30 seconds to 5 min . @swatski were you doing long runs while surfing 5, 10 maybe even 20 minutes of continues surfing with out dropping the rider ?

his girls are GOOD

 

[Betik]

@swatski I hope the dealer gets to the diagnoses soon because you are going to drive yourself MAD with all the possibilities and what you did "wrong". Very informative for us, yet tire-sum for you, Kate & the angels.

 

[swatski]

Odd that turning on the blowers would effect anything in this situation.
Heat rises so the higher engine would be subject to the hot air more than the lower engine yet the higher one starts and the lower one won't. Even with all temperatures being even why the lower one and not both ?
You have to pay close attention to the differences between the two engines and say that the probability of the one engine habitually being hard to start must be something to do with it's position in the water and the fact that it has no issues starting when not set up for wake surfing is all the more reason that the lower position is the real issue. This is one time that I would rather be totally wrong but evidence is what it is.

I hear you.
The argument there however has been the simple vicinity of port engine intake manifold to strbd exhaust manifold (and not the other way around).
To me this seems plausible - add some back pressure in the ballasted port side exhaust and you would have something that can add up to a hard start.

—

 

[swatski]

Lots of good info and so many things to speculate on hopefully there is an exact cause and effect with minimal financial impact .For the hard starting and back pressure we did have this happen while surfing I noticed two things. I had everyone switch sides in the boat to get the surf side motor up and this helped with starting. The other was to allow the boat to idle before cutting the throttle, while the boat was idling I went over to the pee holes and felt the water, after a run it would be fairly hot then it would cool down and the motor would always start up using that technique.

One big variable with surfing is the length of time someone stays up unfortunately they are all very short when we go out 30 seconds to 5 min . @swatski were you doing long runs while surfing 5, 10 maybe even 20 minutes of continues surfing with out dropping the rider ?

Great points, I forgot to mention some of it, certainly warrants that.

So, this last season I have had almost no hard starts that I can recall and I attributed that to taking several precautions we learned during previous seasons.

1. Exactly as you said, we would high idle for a while (between sets) - to cool the engines off.
2. Also, keep the blowers on between the sessions.
3. Lastly, we make sure the throttle binnacles are exactly lined up at neutral, which for some reason also seem to have helped.

Yes - as we have gotten better at surfing we have had many long runs. I have had to stop surfing on occasion this last summer only because my legs couldn’t keep up! That’s how good we got with that new Slingshot, lol.

—

 

[rkim808]

Aloha @swatski sorry to hear about this, I only seen ur thread now. I feel for u my Brother, but I know u will figure it out and get her back to top shape in no time. Prayers?? and Blessing from ur Hawaiian Brother.??

 

[Spooling]

Anxiously awaiting some news... I hope all works out for you!