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What is the level of oil in the cylinder head? Is there enough to cover the valve stem seals or does enough drain back to the sump that they are no longer submerged in oil?
 

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What is the level of oil in the cylinder head? Is there enough to cover the valve stem seals or does enough drain back to the sump that they are no longer submerged in oil?
I wondered that myself. I looked at some bare heads on Ebay, and it looks like the umbrella seal sit pretty high. Valve guides? Head Gasket? Guess we won't know until he pulls the valve cover..... Go for it [email protected]!!!
 

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If on the side stand, pull the left one first. :) It should have the most.....I am surmising.
 

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Discussion Starter · #24 ·
I plan to pull the cylinders after I return from vacation. I'll share an update in a few weeks… Thank you everyone.
 

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'84 CX650E that is evolving into a GL500
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The cylinders on these engines are integral with the crankcase. Just pull the heads ;-)

Start with the head on the side most affected, remove it carefully and post pictures, especially of the o-rings and the oil orifice.
 

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Discussion Starter · #26 ·
I'm back from my vacation, hoping to attack the GL this weekend. At first I thought I'd do a leak-down test, but now I'm thinking just dive-in and replace the valve seals, rings and head gaskets with quality pieces. Hmmm…
 

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It is up to you but 99.99% of the people that tear a motor apart without fully troubleshooting the problem end up regretting it.
 

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Discussion Starter · #28 ·
It is up to you but 99.99% of the people that tear a motor apart without fully troubleshooting the problem end up regretting it.
Correct me if I'm wrong, but the leak down test will only tell me to change some of those items anyway. I'm just suggesting doing all of them since I'm in there anyway.
 

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Correct me if I'm wrong, but the leak down test will only tell me to change some of those items anyway. I'm just suggesting doing all of them since I'm in there anyway.
A leak down test is done with the piston at TDC compression stroke - both valves will be closed. Unless the valves are burned or cracked and allowing air to escape, a leak down test won’t tell you if the stem seals are leaking. Even then, air will travel back out through the carbs before it’s forced out the seals.
 

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It is a relatively simple operation to remove the cylinder heads, this can be done while the engine is in the bike. Changing piston rings is a much more invasive operation, especially if it is not necessary.
 

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If you have the means to do the test it might be a good idea. If it tells you that on or more of the valves are leaking you can deal with that while it is apart....
 

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[
Correct me if I'm wrong, but the leak down test will only tell me to change some of those items anyway. I'm just suggesting doing all of them since I'm in there anyway.
If you want to do more than you need to that is your decision. These bikes are known to go very high miles before needing a complete overhaul. I like to follow the saying “why fix what isn’t broken”. It seems to always be the case that some unforeseen problem arises from doing something you don’t need to do and end up with a big headache. On top of that, if you know what the problem is before you take it apart you know where to focus your attention. I am going to guess you don’t need new piston rings and you can save yourself a lot of work by not doing it.
 

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Discussion Starter · #33 · (Edited)
DouginEasternWashington Not sure what I was thinking, I entirely agree. The piston rings are not being changed, lol. I guess I keep forgetting the cyclinder head construction on this bike.

Upon finding TDC, a great amount of oil spit out of the spark plug hole, must have been pooled up on top of the piston. I then drained the radiator, mostly green but overall blackened, oily feeling. My guess is the head gaskets failed. If I remember correct, they were from a Vesrah whole engine gasket kit.
 

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... If I remember correct, they were from a Vesrah whole engine gasket kit.
I know it is a drag, but keeping your maintenance and build records written down can help!
 

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Discussion Starter · #35 ·
I saved every receipt on this build. I could dig it up, but no real need. I'll purchase a set of head gaskets that the forum suggest.
 

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Discussion Starter · #36 ·
Here are the right head.
209034
209035
IMG_7246.jpeg
IMG_7249.jpeg
 

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Silicone can be used on any gasket except for the head gaskets BUT when it is used it should be applied in either a narrow, thin bead or spread so thin that the only way you can tell it is there is by the sheen AND it should always be allowed to cure fully (overnight).
From the way the silicone is stuck to the mating surface I'd say that was probably assembled with the silicone wet, which can lead to tiny blobs of it being squeezed out into the crankcase where they can get into the oil stream and clog passages.
 

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