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Water in the cylinder

244 Views 6 Replies 6 Participants Last post by  Sidecar Bob
Purchased the CX500 that hasn't been run for 11 years. it's missing the carbs, exhaust and tank.

Before i strip for a rebuild i wanted a quick turnover test i put some coolant in as it was bone dry and on turning over there was coolant out of the exhaust port and in the one cylinder.

No sign of water in the engine oil so I'm hoping it was the head gasket which allowed some coolant into the one cylinder.

Removed the head and the head bolts didn't seem very tight at all so possibly not torqued correctly. !!

There was no gasket left behind on the cylinder side.

Thoughts on the images and is the piston looking overly clean ??

Any help is appreciated.

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Well, you're too far into the disassembly for much diagnosis as to the cause.

Your best path is to continue the assembly and replace both head gaskets. Don't worry about the "clean" piston, they begin that way in a new engine.

You might try turning it over by hand without the heads. This would check if the engine isn't locked up.
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You might try turning it over by hand without the heads. This would check if the engine isn't locked up.
The OP wrote "...and on turning over..."
A leaking head gasket sometimes has a "steam cleaning" effect inside the cylinder, you may be seeing that. No idea why a coolant leak should have that effect just seen it. What are the cylinder walls like?
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What are the cylinder walls like?

All immaculate and no rust or corrosion, it's possibly just been a localised spot as the whole system was bone dry from sitting around dry stored for 11 years before i filled it.

Ii's turning over fine and as Newt says i will change both head gaskets and fire her up before the strip down, the carbs have turned up now and are soaking, rebuild kit for them coming from America.
Be sure to follow the retorquing procedure found here on the forum, rather than that in the manual. Modern gaskets have a different composition that compresses differently.
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It does look pretty clean. When coolant enters a cylinder of a running engine the heat vaporizes, literally steam cleaning everything inside the cylinder.
It it is also possible that the Previous Owner removed the head for some reason (& drained the coolant for that) but had to stop working on it for some reason so after cleaning things up he and put the head back on without tightening the bolts fully to keep it clean inside (the carbs & exhaust would have had to come off for that too).

Welcome to the forum. Please add your location and your bike's model and model year (NOT year first registered as UK paperwork shows) to your profile so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and may or may not have had all of the maintenance necessary to keep it safe & reliable 9even before it deteriorated for so many years) so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
Note that while aftermarket shop manuals are pretty much necessary for people without factory training to work on a lot of makes & models of bike the FSMs for the CX/GL500/650 family of bikes are so well written & laid out that the FSM is really the only book you need and and the aftermarket books are secondary references at best.

I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. If it sat that long you don't need to check the date codes on your tires to know they are over 5 years old and should be replaced no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet).
The original rubber brake lines should be replaced every 2 or 3 fluid changes (= 5 or 6 years) so if your bike still has them I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid).
And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
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