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O Ring replacement

Shoegoo

Member
Member
About to replace the exhaust cam position sensor o ring. Yeah it leaks.
Should I slather some RTV on the flat face of the engine before I put it back together?
 
I say yes, but have not seen the new O Ring yet. Its in the mail included in a kit from Murph. Nor have I seen the old one. So fingers are crossed.
 
Many times the valve cover will leak on the left side around the area of the cam position sensor. So if you still have a leak after replacing the O ring, it's probably a valve cover gasket leak. The oversized O ring does not need RTV on it, and that will just get RTV into the valve train that will most likely wash down into the crankcase and plug up the oil sump pickup. Don't use RTV to seal up engine covers or parts unless absolutely needed, and then only use it sparingly.

If your valve cover is leaking, you'll need to remove it and replace the valve cover gasket, being careful to make absolutely sure the gasket is properly seated on the head surface all the way around. The only place that should get RTV is on the half moons of the valve cover gasket, as shown in the manual at the bottom of page 5-14. Also, if you go to all the trouble of replacing the valve cover gasket, you should also replace each of the rubber washers that go under the 7 valve cover bolts, because they get compressed over time, and these are what aid in applying pressure to the valve cover gasket so it seals tightly.

The real cause of the leaks on this bike is pooled oil in the head after the engine is shut off. In 2015 Kawasaki finally added an oil drain back port on the left side of the head to resolve this issue.
 
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The real cause of the leaks on this bike is pooled oil in the head after the engine is shut off. In 2015 Kawasaki finally added an oil drain back port on the left side of the head to resolve this issue.
Can the 2014-earlier heads be modified to the later spec?
 
Interesting that Kawasaki would come up with a fix and not publicize it. The leak problem has been the reason a number of riders in my area sold their C14 and decided to ride an FJ. The leak was never bad enough for me to dig in and fix until recently. I don,t like droplets on the garage floor. Sadly its almost time for me to hang up my riding boots and convert the closet into much needed pantry space.
 
Geeze...the leak is a minor issue. And the over-size o-ring fixes it if it really bothers you. People actually sold bikes over this?
 
Interesting that Kawasaki would come up with a fix and not publicize it. The leak problem has been the reason a number of riders in my area sold their C14 and decided to ride an FJ. The leak was never bad enough for me to dig in and fix until recently. I don,t like droplets on the garage floor. Sadly its almost time for me to hang up my riding boots and convert the closet into much needed pantry space.

Lots of manufactures just quietly fix problems in model year updates and never publicize it. I suspect it's partially because they don't want to admit that there was a problem in the first place, because this opens up a big can of worms for them. Honda and others do the same thing.

No way to modify the existing head, then?

I haven't really looked into it. You'd need one of the new heads to inspect how they modified it, and then you'd have to remove your head and have it machined, if it even could be done. It would be a lot of work, I'm not sure it's worth the effort.
 
Lots of manufactures just quietly fix problems in model year updates and never publicize it. I suspect it's partially because they don't want to admit that there was a problem in the first place, because this opens up a big can of worms for them. Honda and others do the same thing.



I haven't really looked into it. You'd need one of the new heads to inspect how they modified it, and then you'd have to remove your head and have it machined, if it even could be done. It would be a lot of work, I'm not sure it's worth the effort.
If I ever have the chance to get a 15-up head and I need to remove either of mine for servicing I'll look into a swap. Otherwise they'll stay as-is.

ETA: I've retrofitted later-model Honda parts to earlier models to either fix an issue or improve the performance of the bike, so yes...quite familiar with this concept.
 
Probably would be cheaper to use a new valve cover gasket everytime the valve cover comes off with a light dab of rtv in the corners on the left side. IMHO.
 
Probably would be cheaper to use a new valve cover gasket everytime the valve cover comes off with a light dab of rtv in the corners on the left side. IMHO.
I do this on every bike with a valve cover gasket. FWIW, the exhaust sensor area of my '12 seemed a little oily/dirty but the gasket interface area wasn't.
 
Probably would be cheaper to use a new valve cover gasket everytime the valve cover comes off with a light dab of rtv in the corners on the left side. IMHO.

I replace the valve cover gasket, head hole gaskets, both cam sensor O rings, and the 7 small seals under the valve cover bolts on every bike I do the the valves on. I won't do one without replacing them.
 
This is a photo of the pool of oil on the left side of a 2011 that Fred mentions was fixed on 2015 models and beyond. It also shows the location where the manual calls for the RTV. You can see how the bike on the side stand would send the oil in the direction of the valve cover gasket. I assume a simple hole was added to drain the oil.

CC607B59-D798-4FF7-B055-96C96AF14DD4.jpeg
 
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