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2004 Yamaha sx230 Water In oIl

Compression of 130-140 is low. If you are at a loss, I would try to pull the engine. It will be much easier to diagnose the problem. I do not recommend removing cylinder head while engine is still in boat.
 
Yea engine is coming out engine just had new rings installed so its weird cylinders where good and motor ran good aswell what's normal compression? i hear some ppl say 180 psi but have had some fx 140s and always around 150.
 
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130-140 may be normal for Non-HO. I was comparing it to mine which is HO and around 190. There is a parallel thread running a similar problem with IN2H20's motor. He found badly corroded exhaust manifolds. Not your case, however.
 
WREKS said:
130-140 may be normal for Non-HO. I was comparing it to mine which is HO and around 190. There is a parallel thread running a similar problem with IN2H20's motor. He found badly corroded exhaust manifolds. Not your case, however.
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Oh yea mines non Ho any ways this is my second jet boat last one was a ls2000 that thing was a pain in the ass great when it ran its always 1 motor with me and jet boats that give me hard to solve trouble lmaoo no luck so far with jet boats hope once I tear head off i will see something.
 
Just do not turn head upside down after removing. Pads are unique to each valve.
 
I have had it anyone know where to get a engine? I hear bad things about sbt cant find any used so far almost had 1 ski with a motor but didnt work out.
 
Can you post clear pictures of the cylinder head surface, cylinder block surface, and both sides of head gasket. That may help members help you.
 
WREKS said:
Can you post clear pictures of the cylinder head surface, cylinder block surface, and both sides of head gasket. That may help members help you.
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Yea il get pics of everything tomorrow
 
Also is 415 hours to much for one of these engines if compression checks out might be picking a ski up tomorrow for its engine says it runs but ski needs other work at least its a OEM engine not this sbt crap
 
@jws123 Looks very clean. Was there anything that you found alarming or questionable?
 
WREKS said:
@jws123 Looks very clean. Was there anything that you found alarming or questionable?
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No thats the problem I cant explain why water/air gets into my cylinders maybe heads cracked internally or maybe the block or idk?
 
@jws123 ...Then I would reassemble the head to the cylinder block abiding by the torqueing sequence and values for your engine. I would use a gasket sealer on both sides of the head gasket when doing that. After that, I would do a compression check, then a leak down test. If the problem is in the head, it will be revealed.
 
WREKS said:
@jws123 ...Then I would reassemble the head to the cylinder block abiding by the torqueing sequence and values for your engine. I would use a gasket sealer on both sides of the head gasket when doing that. After that, I would do a compression check, then a leak down test. If the problem is in the head, it will be revealed.
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Ok i will do this if deal falls threw on the ski with the engine in it. I keep wasting money on gaskets and parts on this motor im $700 in the hole already I could always keep the orig one as a spare and fix it one day as these motors from what i can tell are hard to get now the non HO ones.
 
I would reuse the existing stainless steel head gasket. It does not compress. The engine is out of the boat. Now is the time. No need to put exhausts on, just properly torqued head.
 
Nice pictures. I'm in the same boat as my exhaust pipes are clean however my head block looks junked up with calcium deposits.
 
@Russell Did your engine overheat? The deposits are probably a fast acting microbial build up that feeds on residual water left in the cooling system after flushing. This can happen quite easily because the head gasket has small holes that allow water to flush through it but not slimy sessile organic mater that can cling to smooth metal surfaces. Drying out the cooling system after flushing will prevent this stuff, that you are calling 'calcium', from building up.
 
About 2 years ago my starboard engine suffered an over heat situation. It burnt out cylinder 1's plug completely. Now I'm finally getting to tear down that engine. This thread plus others have been helpful!
 
Your thoughts are always welcome WREKS!20210609_195412.jpg
 
Thanks @Russell Cylinder#1 usually takes the hit. It is the farthest from the cooling water inlet to the cylinder water jackets being located by Cylinder#4. For anyone experiencing overheating, prevention is the cure. All these cooling systems need is a little residual water to start sliming up. Once corrected, it must be dried out after the flushing is done.
 
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