2009 212 ss milky oil and low compression

[sgarcia1976]

I have a 2009 212ss with milky oil and low compression. Last season I ran the boat for a short distance without noticing one of the motors had shut down because my safety latch broke off to the hatch of clean out ports cutting off the engine. This may have allowed water to get mixed in on the starboard side of the MR1 engine. I performed multiple oil changes to clean out as much moisture and ran the engine. It seemed to be running well before the end of the season. The beginning of this season I went to check the oil and it appeared milky again. Drained the oil and added new oil and filter. Now it doesn’t want to start. It cranks over but doesn’t have enough compression to start. I removed all the spark plugs which I have a picture attached of how they look. The compression numbers are listed below for each cylinder.

Starboard Engine
Cylinder 1 @ 150 psi
Cylinder 2 @ 110 psi
Cylinder 3 @ 125 psi
Cylinder 4 @140 psi

Do you think there's build up on the valves causing them to be stuck and preventing the engine to crank over, failed gasket, cracked head, or an exhaust manifold breach?
Can anyone provide any suggestions to help with what the issue might be.

 

[DRock3d]

Did you fog it last season?

 

[Beachbummer]

Sorry, if the oil won't clean up you probably have compromised exhaust manifold and the rust that goes with it.

On my sx230 the manifold really does not come out while the engine is in the boat. For all the work required in pulling the engine you might as well rebuild (at least the head) and check/replace the manifolds.

Hope I'm wrong.

 

[sgarcia1976]

Did you fog it last season?

No I didn't fog it.

 

[DRock3d]

Wonder if your cylinders are rusted

 

[Dave burke]

Hard to know for sure but your plugs look really bad to me. I would certainly change them and buy an extra set in case you need them later.

When you changed the oil last year and ran the engine, did you run it a good long while? If you just ran it a bit, it’s possible that you didn’t get all the moisture out. And if you didn’t fog the engine, that won’t help.

If the oil is not milky, I’d start by changing the plugs and see if you can start it. In my experience you should have enough compression the get it going.

If you can get it going, take it for a good run and try and get the crap out (moisture, rust, etc). Then change the oil, check the plugs and check the compression, hopefully it’s more even. If not, it’s most likely the head gasket, likely between cylinders 2 and 3 based on your compression reading,

Hopefully others who have actually changed head gaskets can chime in or try and find threads similar to your issue. Or ask @Julian to point you in the right direction. I’ve fixed blown head gaskets on outboards but never on a Yamaha, don’t know if it’s hard or not.

Based on your symptoms, I’m hoping you probably didn’t get all the moisture out last year and changing the plugs first will get you going. If you ever get water intrusion, based on everything I’ve read and lived, it’s crucial to change the oil and get the engine running quickly, and then run it a lot to boil off any remaining moisture.

 

[Cambo]

The compression doesn't look that bad get new plugs check all the safety switches and try to get it to fire up. Bad compression is 80 and under. Cracked blocks, Heads and breached manifolds seem to be the most common ways to get milky oil. The manifold is the easiest fix . there is a bolt on th back of the motor that will allow you to drain all the oil. Are you in salt water or fresh ?

 

[sgarcia1976]

Sorry, if the oil won't clean up you probably have compromised exhaust manifold and the rust that goes with it.

On my sx230 the manifold really does not come out while the engine is in the boat. For all the work required in pulling the engine you might as well rebuild (at least the head) and check/replace the manifolds.

Hope I'm wrong.

Appreciate the suggestion in regards to re

The compression doesn't look that bad get new plugs check all the safety switches and try to get it to fire up. Bad compression is 80 and under. Cracked blocks, Heads and breached manifolds seem to be the most common ways to get milky oil. The manifold is the easiest fix . there is a bolt on th back of the motor that will allow you to drain all the oil. Are you in salt water or fresh ?

 

[sgarcia1976]

Thanks for your response. I'm hoping it's just the manifold. I'm running in salt water.

 

[sgarcia1976]

Hard to know for sure but your plugs look really bad to me. I would certainly change them and buy an extra set in case you need them later.

When you changed the oil last year and ran the engine, did you run it a good long while? If you just ran it a bit, it’s possible that you didn’t get all the moisture out. And if you didn’t fog the engine, that won’t help.

If the oil is not milky, I’d start by changing the plugs and see if you can start it. In my experience you should have enough compression the get it going.

If you can get it going, take it for a good run and try and get the crap out (moisture, rust, etc). Then change the oil, check the plugs and check the compression, hopefully it’s more even. If not, it’s most likely the head gasket, likely between cylinders 2 and 3 based on your compression reading,

Hopefully others who have actually changed head gaskets can chime in or try and find threads similar to your issue. Or ask @Julian to point you in the right direction. I’ve fixed blown head gaskets on outboards but never on a Yamaha, don’t know if it’s hard or not.

Based on your symptoms, I’m hoping you probably didn’t get all the moisture out last year and changing the plugs first will get you going. If you ever get water intrusion, based on everything I’ve read and lived, it’s crucial to change the oil and get the engine running quickly, and then run it a lot to boil off any remaining moisture.

 

[sgarcia1976]

I ran the engines for a couple of hours last year before the season ended. Although it appears that all the moisture didn't come out. I changed spark plugs and new batteries for maximum cranking but the engines don't turn over. I don't have the minimum compression of 150 psi to kick over the engine. Is it possible to try to lubricate the pistons by adding a very small amount of oil through the spark plug holes to try to free them up. I thought I read a post of someone trying this. Please advise your thoughts or if you have any suggestions. Thank you.

 

[Jores]

oil in the cylinders will help worn out piston rings but i don't think it would help if the valves are the problem.

 

[DRock3d]

Valves are unlikely to stop the engine from turning over, seized rings could. There's also the possibility that this guy is using the term "turn over" incorrectly

 

[bjlkemper]

You can add a tablespoon of oil to the cylinder through the spark plug hole and retake compression. If compression comes up then you know piston rings are leaking. However, if it stays the same or comes up just a few PSI then this can be deceiving. Because if the valves got salt water on them they could be sticking a small bit in the valve guide and not sealing completely. My concern would be the difference between cylinders 2 and 3. With both of them being low and adjacent to each other that normally indicates the bad head gasket. In the valve train, head gasket and piston ring area it can be tough to really pinpoint mainly because each small thing can point to the other. Carbon on exhaust valve can keep them from seating thus not allowing full compression. Slightly open valve during compression stroke can bend the valve thus not allowing it to ever close, normally the top of the piston will show a mark if it hit the valve head (borescope can help look at top of piston if you got one). If it where mine, I’d pull the head check the valves are clean and seating properly, replace the head gasket and check the compression again. While I had it off though, I’d look at the injectors and make sure nothing is on the tip of them from possible rust/salt/carbon and also look and inspect the exhaust manifold….just my 2 cents. But I’d have a few beers doing it. Really more than a few but that is me.

 

[sgarcia1976]

Here's an update. I was finally able to get the engine to kick over by spraying a bit of starting fluid in the carburetor. I performed about 5 to 6 oil changes to clear out the milky oil. The compression for each cylinder is about 170 to 175 for all 4 cylinders now. The only problem i have is a check engine light. It flashes once with a pause than blinks 3 times. Is this code 13? I tried swapping the coils with the other engine but get the same flashing lights come back on. Has anyone experienced the same flashing light sequence and if so how did you repair it? Please advise.