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Milky oil

Dbs22

Member
Messages
1
Reaction score
0
Points
10
Boat Make
Yamaha
Year
2007
Boat Model
AR
Boat Length
23
2007 AR230 with milky oil in port side engine. Starts and runs. Took to dealer here in Michigan. They drained oil and put fresh oil in. Hooked up to a hose and ran for three minutes and oil was milky again. They said it is a cracked block or cylinder head. Said they wouldn’t take motor apart because they can’t get parts or new motor for this model any longer. Never did compression test or anything. Just doesn’t sound right to me. Any advise or recommendations are appreciated. TIA.
 
Based on what you’ve said, I’d do a compression test. Could be several things, not necessarily a cracked block or head.
 
I don't necessarily disagree @Dave burke . Could be other things. But I would say that it is likely a head/block problem, given what we have seen around here...

Sorry, @Dbs22 . I don't think it is good news. In my view, they probably did you a favor by not continuing to work on it (and charging you). I would change the oil myself, were I you (you don't want to let the milky stuff sit in there--use cheap oil, tho), then buy a compression test kit off Amazon. But in the end, I think you are probably going to wind up either getting an SBT engine or harvesting an engine from a donor boat... Some here have used JB Weld to fix cracked blocks, but the fix usually does not last long-term and performing the repair is rather advanced.
 
My friend had his exhaust manifold breach at the water jacket and it caused the milky oil. It was the port motor so the manifold was pulled without removing the motor
 
Good point. We have had exhaust manifold issues, as well. That is more replaceable than the block... If you can get one.
 
Could it also be the head gasket @tdonoughue? Do you have to pull the engine to replace that? I’m guessing no but really have no idea
 
Yep--thus the compression test you recommended is probably prudent. But, that said, I have not seen many failed head gaskets, and I have seen several cracked heads and manifolds.

I haven't had to take mine apart on the top end, but I am too guessing that you would not have to pull the engine to do the head gasket. That said, it may much easier on the back for us old folks to pull the engine. Especially when you get to those bolts on the aft side of the engine.
 
A breach between the water jacketing and the oil guides will not be reflected in a compression test.

This type of breach is one of the leading causations in turbo cars head gasket issues. The tell tale sign is "pushing" of coolant into the overflow. It is not viewable in any other context.
In our jetboat context we don't have the luxury of an overflow tank for the coolant. Water is making its way into the oil guides somehow, but will not be visible in any other location. This to me suggests a head gasket breach between as I said one of the oil guides and a cooling jacket. It probablly does not involve the cylinder at all, the plugs and exhaust would be telltale then.

If it was a block it would most likely be viewable from the exterior. So my vote is "Head", most likely head gasket breach apart from the cylinder interior.

Lots of labor, but you could pull the involved head without pulling the motor.
Have fun on your coming adventure, Good Luck !!!
PS use aerosol K Copper on your headgasket replacement before you install.

***Just did a little research, apparently your year and model encounters known problems with the exhaust manifold (breach).
 
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Do you have the 1.8?

I had cracked head. Never heard of small displacement one cracking but two have had problems with EM corrosion leading to milky oil.

I think [HASH=4158]#Werks[/HASH] has pictures on it

Taking EM is doable.
 
Do a compression test!
 
I thought we had seen several. Or am I thinking of exhaust manifolds? I thought some were heads...
 
I thought we had seen several. Or am I thinking of exhaust manifolds? I thought some were heads...


I have only owned the 1016 in VX and they were solid.

The one is question I think is a 1052 and still best long running engine before the 1.8

My 1800 HO is one that suffers from cracks in head.

it is more prevalent in SHO or SVHO that have NA 1.8 1816 cc engine.

Ive read more EM corrosion leading to oil contamination versus cracked head with 1056.
At Least it is the least complicated part to remove and replace for diy if it solves issue

When my head cracked there was no compression loss so that is important to know if each cylinder is 180 to 160
Otherwise head needs to be pressure tested to find leak or you will at least see if it was blown head gasket near oil passage near cylinder one.

You can do most things dealer will do or did to confirm your next step.

I found place that sells rebuilt 1.8 head after waiting for mine last year. maybe he has others. I can ask if if helps.
 
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When I bought my SX210 (FRT 1100's) it was at the recommendation of a mechanical guru friend of mine, in lieu of the larger 1.8's. He pointed out that the 1052cc marine engines had an almost 30 year development.. Capable, reliable,...not super powered but then again that is part of the reason they are so long lived.
 
My 'milky oil' problem traced back to the cylinder head. It is well documented.
 
My 'milky oil' problem traced back to the cylinder head. It is well documented.

It was corrosion or putting in head that JB weld was used iirc. Right?

It was cracked like the 1.8
 
It was the jb weld fix. Head was not cracked. 1050cc.
 
When retorquing head, I thought the service manual angle specifications where too high for the center bolts. I was concerned that I might crack the head so I eased up on some of the values.
 
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