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Sx230HO bad cylinder or mechanic needed Las Vegas

Maxputze

Active Member
Messages
6
Reaction score
0
Points
40
Boat Make
Yamaha
Year
2005
Boat Model
SX
Boat Length
23
I am from the Las Vegas area and am experiencing issues on my starboard engine. I did my routine oil change and checked the oil levels out on the lake only to see that there was oil in the intake manifold and the oil dipstick was well past the fill line. (When cold the oil was badly visible on the stick) I furthered my investigation and did a compression test only to find what appears to be water mixed with carbon deposits in the 3rd cylinder along with a compression of over 300psi. I am assuming it may be the headgasket but honestly I’ve never worked on a boat engine before and am seeking a professional shop which isn’t the two dealerships in Las Vegas which I have allready tried.
 
Blind guess - the all too common ECM failure holding an injector wide open and filling the crankcase with gas. @bronze_10 is going through this right now.
 
Don't ain theboil and see how much u get out. There is a post on here on how to pull the bottom drain plug to get all the oil out. I pulled 9 quarts out of a motor that hold 4.5 to 5 quarts!
 
Ok I’ll try draining the oil from the bottom tommorw but it still confuses me why it would only affect one piston and when I cranked it the spark plug port shot out water like liquid which didn’t smell like gasoline.
 
It certainly could be something else, just throwing out a real common issue. It only holds one injector open, so it only kills one cylinder. Same scenario every time.

As for smelling like gas - you weren't expecting it to I'd guess, and probably weren't looking for it. It could've also been heavily diluted engine oil as well, dampening the smell. Sometimes, with preconceived notions in our heads, we only see what we expect to see. Knowing this possibility, you might see things differently tomorrow. Believe me, I get tied up on cars all the time thinking I know the problem before diving in, I've gotten wise to catching myself doing it now though.

Again, it could easily be something else. There have been a handful of cracked blocks, and I'm sure some headgasket woes as well. But, the compression test would be telling a different story right now. It's artificially high with all the liquid in there (can't compress a liquid), but if there were a bad gasket/cracked block or whatever, it'd certainly force it out that way.
 
No way it's 300 psi. Double check you gauge. Did you tow it or drive with only one engine?
 
No way it's 300 psi. Double check you gauge. Did you tow it or drive with only one engine?
I drove with one engine but here is an image of the gauge.
 

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It certainly could be something else, just throwing out a real common issue. It only holds one injector open, so it only kills one cylinder. Same scenario every time.

As for smelling like gas - you weren't expecting it to I'd guess, and probably weren't looking for it. It could've also been heavily diluted engine oil as well, dampening the smell. Sometimes, with preconceived notions in our heads, we only see what we expect to see. Knowing this possibility, you might see things differently tomorrow. Believe me, I get tied up on cars all the time thinking I know the problem before diving in, I've gotten wise to catching myself doing it now though.

Again, it could easily be something else. There have been a handful of cracked blocks, and I'm sure some headgasket woes as well. But, the compression test would be telling a different story right now. It's artificially high with all the liquid in there (can't compress a liquid), but if there were a bad gasket/cracked block or whatever, it'd certainly force it out that way.
Thanks for the advice I’ll definitely double check tommorw and upload some images of what I’m seeing and it does make sense that if the head gasket was damaged that high of compression wouldn’t be likely. I’m hoping it’s an easy fix as it’s pretty annoying to get to the top end of the engine because of the plastic filter housing.
 
A hint.. Pull the oil out of the oil tank first... Then pull the filter.. Then find the bottom drain plug.. (Its a basturd to get to).. The oil that came out of my engine was about half gasoline but it didn't have a strong smell of gas at all. As a matter of fact @veedubtek and I smelled it in bimini but could get a gas smell..
 
I drove with one engine but here is an image of the gauge.
If you drove on one engine you probably filled the other engines with water, it drained past the rings, into the oil. That's what happened in mine. (I hope, will find it soon)
I'm highly skeptical that gauge is accurate. I'd verify it against another gauge. Or maybe there was still water in the cylinder when you ran compression?
 
That's true too.. If u drove on one engine it should be at idle speeds. With mine I first detected something wrong due to a very very strong odor of gasoline when it was running and seeing raw gas floating in the water behind my boat..
 
So today I drained all the oil out of the engine it seems to be pretty dark in color (refer to image). I will try to get a new oil filter and refill the oil soon then I’ll crank the engine over a few times to get the water out of the 3rd piston. I’ll put in new spark plugs and clean the intake cover from all the oil that was sprayed inside of it and pray. By the way what would you guys recommend for removing carbon buildup in the engines I was looking at using some seafoam.
 

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That's true too.. If u drove on one engine it should be at idle speeds. With mine I first detected something wrong due to a very very strong odor of gasoline when it was running and seeing raw gas floating in the water behind my boat..
When I drove I also saw an oil like film on top of the water.
 
I am from the Las Vegas area and am experiencing issues on my starboard engine. I did my routine oil change and checked the oil levels out on the lake only to see that there was oil in the intake manifold and the oil dipstick was well past the fill line. (When cold the oil was badly visible on the stick) I furthered my investigation and did a compression test only to find what appears to be water mixed with carbon deposits in the 3rd cylinder along with a compression of over 300psi. I am assuming it may be the headgasket but honestly I’ve never worked on a boat engine before and am seeking a professional shop which isn’t the two dealerships in Las Vegas which I have allready tried.
HALLO
Lately i bought YAMAHA SX 230 ,year 2005 ,with 2 engines .I'm looking for hole electric box with wires .because i have only one ,box is called YAMAHA 6B6.
MODEL of boat SRT 1100-D. VIN YAMCS384D505
Computer in the box has these numbers :6P6-00, F8 T94874, 5129
Outer computer has these numbers : SH 678B-13, G4D.3
Do you have something like that ?I can send pictures if you like .
Iam looking forward for your replay .If you don't have it ,do you know where i can find it ?My mail is roman@wiertelak.pl
Kind regards,
Roman
 

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