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Oil weeping valve cover?


Buckaroo

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I'm losing about 1/2 qt of oil in 25 hours. I see a small film streaming back between the top and lower cowl on the right side. This leak is driving me crazy. 

There is no service for 100's of miles in my location. I have to do this myself. 

Can someone walk me through the steps to remove the valve cover. What precautions to take, tools to have at hand and potential parts I'll need. 

Thanks in advance!

Buckaroo 

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I changed the oil about 25 hours ago and at that time the stick showed oil almost at the top of the stick depression. Beginning each subsequent flight while checking the oil I can see it slowly decreasing more and more each flight. Now it's below 1/2 way on the stick indicator.

After a two or three hour flight I get a oil film stream going back from the right cowl seam to the bottom cowl back to the right baggage door and accumulating below the baggage door. 

Taking off the cowl no visible oil can be seen wetting any of the inside parts like the battery etc which is directly behind the weeping right rear valve cover. 

When sliding finger under rear right valve cover finger get slightly wet. 

Question: Can I just take a Allen wrench and remove the cover and simple try a new seal or other forum fix? 

If this was my lawnmower or motorcycle I'd dive right into it but airplanes not so much!??

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A weeping valve cover is fairly common. Some can be stopped and some not. There is a large "O" ring for the seal. You can try to torque it again to  90" lbs, but I doubt it will work. I have tried up to 110"lbs and still didn't work. I have tried at time 4 different "O" rings without success. I have lightly sanded the valve cove edges with no success. It have applied Loctite 598 with no success.

You might get lucky and one of these may work, but may not. I see a number of CT's come in with this tiny oil mark on the left outside of the cowl. This is a very minute amount of oil and looks worse than it is due to the higher velocity wind spreading it.

 

When you put your oil in did you put in 3 liters of Aero Shell or 3 qts. Of something else. 3 liters is about 8 oz. more than 3 qts. It should be liters and of course this also is filling an empty oil filter. Don't second guess the oil amount at the oil change. Always use the full 3 liters of Aero Shell.

An oil level check with a gurgle can lie to you. Just keep an eye on it. I get calls on this every so often on a Rotax engine. If you are really using or leaking that 1/2 qt. every 25 hrs. it will leave a mess all over the belly of the plane.

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I guess the only thing I can do is try a new o-ring and re-torque. 

Yes I put in 3 liters of Aero Shell and a new Rotax filter. It indicated high on the stick. 

Im still planning my run to Rocky Mountain Kit Sport to see Mark Pringle for the annual and 5 year hose job. Maybe they can stop the leak!

LEE do you sell parts unique to the FD that are typical wear out items I can get from you to take to them? I'd be interested in buying all those items including unique 5 year replacement parts that he may not have in stock. I'd guess there are rubber parts that fit the CTSW exclusively.  Even items that still may be ok I'd rather buy new ones just to have in case so I don't end up waiting for. 

Thanks Lee!

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Yes, I ordered the big valve cover O ring and the little guy from Lockwood in Florida. $34.00 and $6.00 to put in an envelope and mail to Montana I'll be set. A new valve cover is $200 so I'll do a fine sanding on this one as well and add a little appropriate Locktight and see what happens. 

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If it's just "weepy" and not a dripping leak I can't see it's a problem, especially if as Tim said, there is no measurable loss.  I had a similar leak that was fixed by re-torquing the valve covers, and another small one fixed by tightening the oil pressure sender fitting.  These type of tiny leaks seem pretty common.  

I was talking about the first leak I found with some aviation "old timers", and they laughed at me and said "it's an airplane engine...they all leak oil somewhere!"  There is probably some truth to that; air cooled engines go through more dramatic heat/cool cycles than water-cooled engines, and so expansion/contraction of different materials causing leaks is more likely.  This is less so in the 912 series because of the liquid-cooled heads, but the rest is still air cooled and prone to these issues.

PS:  *Any* type of leak annoys the hell out of me, too. :D

 

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2 hours ago, FlyingMonkey said:

If it's just "weepy" and not a dripping leak I can't see it's a problem, especially if as Tim said, there is no measurable loss.  I had a similar leak that was fixed by re-torquing the valve covers, and another small one fixed by tightening the oil pressure sender fitting.  These type of tiny leaks seem pretty common.  

I was talking about the first leak I found with some aviation "old timers", and they laughed at me and said "it's an airplane engine...they all leak oil somewhere!"  There is probably some truth to that; air cooled engines go through more dramatic heat/cool cycles than water-cooled engines, and so expansion/contraction of different materials causing leaks is more likely.  This is less so in the 912 series because of the liquid-cooled heads, but the rest is still air cooled and prone to these issues.

PS:  *Any* type of leak annoys the hell out of me, too. :D

 

Yes but she's using 1/2 at in 25 hours!?

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