Honda CX 500 Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
507 Posts
Discussion Starter · #1 ·
Today I finally had time to tear into my engine again to replace the cam chain and tensioner. I decided to pull off the breather tubes just to get them out of the way.



When I did so I notice a small amount of gooy nasty stuff flop out. Upon further inspection I noticed it had came from the breather tubes. I scooped some up with a screw driver and it looked almost like snot. It was gray and nasty.



Thinking that it was probably coolant of some sort I tasted it. Sure enough it tasted sweet like coolant.



Now I am wondering what might be wrong? I could only think of two things, blown head gasket or a cracked head.



What do the rest of you think?
 

·
Registered
Joined
·
1,556 Posts
Today I finally had time to tear into my engine again to replace the cam chain and tensioner. I decided to pull off the breather tubes just to get them out of the way.



When I did so I notice a small amount of gooy nasty stuff flop out. Upon further inspection I noticed it had came from the breather tubes. I scooped some up with a screw driver and it looked almost like snot. It was gray and nasty.



Thinking that it was probably coolant of some sort I tasted it. Sure enough it tasted sweet like coolant.



Now I am wondering what might be wrong? I could only think of two things, blown head gasket or a cracked head.



What do the rest of you think?


I do not know about the mechanical issue but if your snot is gray, gooey, and nasty like you describe tell me where you have been so I know not to go there!



 

·
Registered
Joined
·
351 Posts
I always thought it was condensation mixed with oil, but I never ate any.
 

·
Super Moderator
Joined
·
15,414 Posts
Yeah it's condensation mixed with oil from the crank case. Clean it out and things will be fine.



Do you taste the other fluids of the bike too? If you want a fun one try brake fluid.
 

·
Registered
Joined
·
289 Posts

·
Registered
Joined
·
35 Posts
OK, Question....this liquid... if there was enough of it could that or the vapor be recirculated back into the engine and hydro-lock it? Also could someone explain hydro-locking in-depth to me? Specifically where/why it would happen, I'm not exactly sure I have a complete grasp of this concept. Thanks.
 

·
Registered
Joined
·
289 Posts
OK, Question....this liquid... if there was enough of it could that or the vapor be recirculated back into the engine and hydro-lock it? Also could someone explain hydro-locking in-depth to me? Specifically where/why it would happen, I'm not exactly sure I have a complete grasp of this concept. Thanks.


A hydro-lock is where there is more fluid (which does not compress) than volume in a cylinder. This would take place on a compression stroke when the piston is traveling up to compress the fuel/air mixture - or in the case on a hydro-lock where it gets stopped by the fluid. Technically speaking, air is a fluid, too.



A hydro lock typically would happen when a carb leaks gas into a cylinder. Although a hydro-lock could be caused by coolant or oil under the right circumstances.
 

·
Registered
Joined
·
35 Posts
A hydro-lock is where there is more fluid (which does not compress) than volume in a cylinder. This would take place on a compression stroke when the piston is traveling up to compress the fuel/air mixture - or in the case on a hydro-lock where it gets stopped by the fluid. Technically speaking, air is a fluid, too.



A hydro lock typically would happen when a carb leaks gas into a cylinder. Although a hydro-lock could be caused by coolant or oil under the right circumstances.




OK, could carbs not being set right, or too much ether, or liquid in airbox do this? and so to relieve this...just remove the plug and the engine should crank, yes? Thanks.
 

·
Registered
Joined
·
289 Posts
OK, could carbs not being set right, or too much ether, or liquid in airbox do this? and so to relieve this...just remove the plug and the engine should crank, yes? Thanks.


With a carb, it is more likely that a float gets stuck or a seat doesn't seal and fuel flows into the cylinder when the engine isn't running. This likely would be the left cylinder when the bike is left on the side stand. If the air box was full of a fluid (water, oil, coolant, etc.), then this could cause a hydro-lock situation. In the case of the airbox being full, then draining the foreign fluid should correct the problem once the cylinders were cleared.



Another scenario of a hydro-lock (and potentially catostrpohic to the engine) is having the engine ingest water while running. An example would be riding through a deep creek and the water entering the carbs while under power. The water entering the cylinder could hydro-lock the engine (if enough made it through before the engine died) and could cause other damage from shock cooling. The sudden hydro-lock would put enormous forces on the rotating assembly (crank, rods, pistons, bearings) which would likely result if deformed bearings and bent or broken bits.



Are you having a hydro-lock problem? If so, then it might help to start a topic specific to your issue.







Jwink, do you have contaminated engine oil?
 

·
Super Moderator
Joined
·
15,414 Posts
If the air box is that full then you have a bigger problem.



The hose that goes from the heads to the airbox would first fill up with water and then you would probably need several quarts of water to fill the airbox to the level where it could go into the carbs.



If you want to save yourself some trouble get a security system so the neighbor kids cant fill your airbox with a garden hose. Besides that drain it once a year. Many times I have went to drain it and there wasn't any extra. This last week I did it and got about a cup.
 

·
Registered
Joined
·
8,423 Posts
Just prior to riding season over here on my CXs I remove my Air-filter and it's stand and check.If bad I remove my breather plugs and then squirt some washing up liquid in the box.Move it around with an old paint brush and then pour a couple of kettles of boiling water in there to flush the box and pipes through.Then dry it out with some tissue/toilet roll.

There can be a lot of sludge build up depending on how long the bike has been left without a check in there.Present ride seems better than my other one and was done last year but didn't need anything doing to it this year
 

·
Registered
Joined
·
507 Posts
Discussion Starter · #12 ·
I did not notice any contamination in the engine oil.



I thought at first that it was just oil mixed with some condensation but why would it be sweet?



If I did have a head gasket issue or a cracked head could this area get a substance like this built up?



I don't taste everything but I have tasted most fluids. IDK why but I just have. At work when someone has a leak I usually ask "well what's it taste like?" or someone yelles out "hey Tony come taste this"



I replaced the headgaskets when I first bought the bike last year. I am considering tearing them apart again and making sure all surfaces are clean and hitting them with some sealant, while the engine is out.
 

·
Super Moderator
Joined
·
15,414 Posts
Don't rip into the heads as the sweetness could have came from prior head problems. If you think you really have a problem give it a thorough cleaning with hot soapy water and come back and taste it in a month.
 

·
Registered
Joined
·
507 Posts
Discussion Starter · #14 ·
Yeah that is true. This is the first time I have ever pulled those tubes off.



Thanks all around.
 
1 - 14 of 14 Posts
Top