Help! Bad Day On The Water. 0 for 2. Ongoing Milky Oil Problem Part 2

[14SX190]

Hi

I need help pointing me to right direction on what to expect.Boat is used to me. On both short outings It runs like a dream. Turns 7200 and hit 45 but come home to milky oil twice. I ran it on hose for 30mins and no contamination after several oil changes. Could high pressure from pump be reason it doesn't show up on hose?

https://jetboaters.net/threads/need-help-with-new-used-boat-milky-oil-story-from-day-one.27259/page-2

During todays outing it ran great but shifter control starting clanking. 30mins into riding IC the reverse bucket cable snaps when I slowed down to go under bridge. I only had reverse.
Jumped in the water and rigged rope to tie bucket in up position only to have to loosen it it start it in the down position. Got me back to dock through at 40 mph
So I'm looking for a cable now and might replace steering too. The Thrust vector it has it's terrible. Going to get the Coba Jet Ultimate as soon as I get oil contamination situated

Decided to check oil at dock and to my surprise there was toothpaste in oil cap and oil was pasty. Ran diesel down crack case when I got home and sucked out all the contaminated oil I could.
At that point I took oil cooler and the rest of mixture poured out holes as I cranked engine over. There is one bolt that has lost it threads and does not tighten. Could it be helicoiled? I rigged up oil cooler tester and its holding pressure so its not leaking.

Then used whole can to fog cylinders. crank case and inside oil cooler holes to block. Left compartment open, oil cap and dipstick off and running portable ac.

The only reason left for milky oil is the blown head gasket or cracked cylinder?
So it off to dealer on Monday for leak down / do they pressurize cylinder(on or off)? or does it completely off for visual inspection.
What do you think shop charges will be like for testing of cylinder head or to replace gasket?
I saw video if adjacent cylinder is also low on compression it will be head gasket? What would cause a head gasket go bad? Over heating?
I had 180 in cyl 1,2,4. #3 had 160. Today cyl#2 has 160. WTF!

Sorry for long rant but I am so bummed right now and I'm at the limit of my mechanical skills. Anyone in South Florida willing to give me a hand?

Thanks

 

[Dave burke]

This sucks. Sorry to hear about your problems.

I’ve not had issues like this with my Yamaha but have experienced blown head gaskets in the past with outboard and cars.

I’ve never tested the compression in my boat but based on the other engines I’ve tested 180 lbs seems really high. Hopefully others can confirm if this makes sense for a Yamaha.

In my experience with outboards, a 20 lb variance between cylinders isn’t bad. If the head gasket was blown, I think you’d see a much greater variance.

Can you pull the head off? Maybe check the FAQs and see if someone has written this up? Not sure how hard it is to do on these engines.

Sorry I can’t help more.

 

[Dixie Highway]

Am I wrong in assuming the oil cooler stripped bolt could be the cause of the water intrusion? This is coming from a place of ignorance as I’ve never had one apart but it seems that since water runs through the cooler a loose bolt could be the culprit. Your compression numbers look good, next step would be a leak down test to verify.

 

[Dixie Highway]

The rust looking stains around what appears to be the stripped bolt is very telling.

 

[14SX190]

Am I wrong in assuming the oil cooler stripped bolt could be the cause of the water intrusion? This is coming from a place of ignorance as I’ve never had one apart but it seems that since water runs through the cooler a loose bolt could be the culprit. Your compression numbers look good, next step would be a leak down test to verify.

Unsure, but the water is in separate sealed chamber apparently.
My DIY pressure tested held air buy who knows

Anyone know what to expect to pay for labor to head gasket. I'm worried its cracked.

 

[14SX190]

This sucks. Sorry to hear about your problems.

I’ve not had issues like this with my Yamaha but have experienced blown head gaskets in the past with outboard and cars.

I’ve never tested the compression in my boat but based on the other engines I’ve tested 180 lbs seems really high. Hopefully others can confirm if this makes sense for a Yamaha.

In my experience with outboards, a 20 lb variance between cylinders isn’t bad. If the head gasket was blown, I think you’d see a much greater variance.

Can you pull the head off? Maybe check the FAQs and see if someone has written this up? Not sure how hard it is to do on these engines.

Sorry I can’t help more.

Update.

Since I am deep into finding problem I went ahead and took valve cover off, EM and intake. Left nothing but long block in case they say engine ha to comes out.

If so, Ill change intermediate bearing since I'm there for peace of mind.

I was able to see cam lobes and valves when they closed and did leak down. Needle was is the green

Definitely hear air escaping down near cylinder 1.
Its fast when tester first reads and then its a swoosh every 5 secs.
I didn't go any further as I want tech to verify location so he has better idea when they take it off.

I hope I have saved a few shop hours and only get charged 1 hr for head removal to find leak and go from there.
Best case head gasket but my luck its a crack

Oil cooler holds over 30psi.
Will have to get helicoil for that bolt if possible.

Not sure if that is supposed to be color of cam gear or chain. I'm think boat had sank.....