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Part 4 Engine Reassembly To End Milky Oil

Did you see any signs of water intrusion on the EM gasket. If not, try leakdown?
 
I didn't read your previous threads so this may have been covered. Did you do any disassembly of the bottom end or just remove engine and have head redone ?

Bottom end unretouched

How did you apply permatex ?
 
Bottom end unretouched

How did you apply permatex ?

If that's the case the chance of moisture mixed with the old oil in the nooks and crannies would be high. Oil pump, lines and cooler to name a few. As far as permatex for an area like that I either dab a thin layer on the part with my finger or a thin bead in the middle. Give it a couple minutes to start to set up then attach. You want to avoid it squishing out into the water jackets. As long as both surfaces are straight the factory metal gasket should seal just fine.
 
I use an artist paint brush to apply a thin non-drip layer using the sealant I mentioned, both on gasket sides and head and EM sides.
 
Did you see any signs of water intrusion on the EM gasket. If not, try leakdown?

Bolt broke as I was checking torque.
Will do leak down next.

Hard to say. Had a lot of condensation due to hatch being closed and cover on.
Going to park in it in garage again to leave everything open and ventilated

Hoping EM repair works.
 
TDC for #1 and #4 are the same. TDC for #2 and #3 are the same, just 180 degrees from #1. I use a wooden dowel to determine TDC for #1. To the best of my knowledge, I think, even close will do. Better still follow the service manual. I do not have a dial gauge. I do not think it is necessary. Keep reporting!
 
TDC for #1 and #4 are the same. TDC for #2 and #3 are the same, just 180 degrees from #1. I use a wooden dowel to determine TDC for #1. To the best of my knowledge, I think, even close will do. Better still follow the service manual. I do not have a dial gauge. I do not think it is necessary. Keep reporting!

I made scribe markings on PTO and reference on block to find TBC [HASH=4213]#1/[/HASH]#4 and on [HASH=4214]#2/[/HASH]#3.
Fingers crossed tomorrow.
 
You can double check by looking at cam alignment marks. If you do not see them when #1 is at TDC, rotate coupler 360 degrees!
 
Update:
Morning ran longer at work and took a while to permatex every exhaust surface carefully
Ran out of time to ramp 4pm launch cut off time.

That permatex is no joke. I think that sealed any water to exhaust hypothesis.
Ran it on hose ~10mins and still have same mineral Yamaha oil color
No signs of contamination from previous oil on dipstick.

Next test window is Friday.
 
I would run on hose before launching and keep checking appearance on dipstick. Higher rpms are going to be telling. Friday will be true test. How did leak-down go?
 
negative on leak down yet.
Have boat away from garage and compressor.
 
update.

Head is coming off.

JA mechanic didn't tighten valve cover. One bolt was completely threaded itself out. Also, didn't theradond gasket half moon back.

I am questioning his torquing HG at this point.

Took him twice to do TC b/c he flipped cams.

[HASH=4158]#Werks[/HASH] can I still try leak down with Intake off.

This was my oil after 2 changes on water.

Water was great and boat did its 40+mph at 7800 rpms.

Had Cruise ship cross my bow as it was going out Government Cut.
 

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Yes, that is certainly not getting better. I would call that worse, in fact.

Bummer.

Bet the cruise ship didn't have water in his oil...
 




 
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Though I have to wonder who is running an empty cruise ship around.

Or, alternatively, who is on a cruise ship under the current circumstances...
 
Better to do it with exhaust and intake off. Easier to hear where air is escaping. In fact, wait to reassemble until you have a definite idea where air is escaping.
 
BTW,There is a thread where a member had a cracked head, possibly due to over torquing. Sometimes it takes several tries to get the timing chain right on cams. Follow the service manual!
 
I hope you get this figured out wrenching on these boats in the summer heat is brutal . When it does get resolved there is no better feeling knowing that it has been fixed and all your work could help others.
 
update

Plugs look good for 1Hr.

@ [HASH=4158]#Werks[/HASH], I tried performing leak down and readings on #1 and #2 @ their corresponding cam marks were green.
When I tested TDC #1 it was green. Tested #4 it was Red
When I tested TDC #2 it was green. Tested #3 it was Red.
I don't know how to interpret that?

I then tried to copy JIm's performance procedure to pressurize cylinder is inconclusive.



Here's what I did.
I removed hose from Thermostat and put fitting for air.
Removed EM again and used gasket along with thick plastic covering(pool salt bag) and reattached EM.
Disconnected all water lines going into square box plugged them including "Y" line going to bottom of water fitting of exhaust

I set compressor at 10Psi and hose gets firm see no bubbles anywhere but compressor never shuts off meaning a leak somewhere.

I am leaning towards taking head off again. Making sure of TDC# 1 and cam marks lined up with arrow the disassembly and reassembly should be easy for me to do versus paying someone again.

Looking for last ditch help before I throw in towel and wait for 21 to come out.

Or if anyone following interested knows what I paid and whats wrong with it PM me if your interested in almost perfect boat that has had everything redone.
 

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If the head is not cracked, as in the video you posted, then doing the leakdown test can help. All valves leak. It is the rate at which they leak that matters. The leak down test shows a reasonable rate. I would try using a 100 PSI instead of 10PSI. Red probably means "FAIL." Green probably means "PASS." If the compressor noise is far enough away from the cylinders you are testing, you may be able to hear the air escaping from the exhaust manifold port of the cylinder you are testing. There are a number of cooling water passageways going into the cylinder block. That is where you want to listen. In the image, it is next to the alignment pin.
20200808_182644-jpg.128991
 
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