Jump to content

Oil in the drip tray


Ed Cesnalis

Recommended Posts

I am quite sure, oil makes it sometimes from the downside of the drip tray to the upper side. If oil exits out of the venting hose of the oil container, air can transport this oil to the downside of the drip tray in flight.

 

Have a look at the downside of your drip tray. Maybe you will find tracks of oil there.

 

Greetz

 

Markus

Link to comment
Share on other sites

I was having an issue with some oil on my engine, even a little making its way to the seam between the upper/lower cowls and streaking down the side of the airplane.  Just a small amount.  But when that happened, I also found some oil in the drip trays and tiny spray droplets on the valve covers and plug wires.  

 

I figured out it was oil getting thrown back over the engine from a loosened fitting that was weeping.  I inspected and tightened all the oil fittings and the problem was gone the next flight and has not recurred.  I *think* the fitting that was leaking was the taper fitting where the sender is at the front of the engine.  That fitting doesn't use teflon tape or anything to secure it and I guess it just backed off a thread or two.

 

During this period (about 3-4 flights) I never saw the oil level decrease in the tank, so it was really a small amount of oil.  Something to consider and check, at least.

Link to comment
Share on other sites

Oil would have to come from an outside source other than the carb. If you have any fluid in the drip tray other than dirty grim then that is mixed with fuel. That means your gasket is starting to leak. Blown back oil tends to be slippery and or dirty, but not fluid.

Link to comment
Share on other sites

Oil would have to change me from an outside source other than the carb. If you have any fluid in the drip tray other than dirty grim then that is mixed with fuel. That means your gasket is starting to leak. Blown back oil tends to be slippery and or dirty, but not fluid.

 

The oil in my trays was a  film, not pooled liquid.  Sounds like that's in line with what you are saying.

Link to comment
Share on other sites

BTW, I got some advice from Lockwood not long ago about the bowl gasket replacements.  They said that the gaskets as they come are too thin to seal well.  They recommended soaking them in gasoline overnight before installing, which swells and softens them and makes them seal better.  It worked for me.

 

They also gave me another trick if you still have leaks after that; if anybody needs that info, PM me.

Link to comment
Share on other sites

Last year I had an issue with leaking carb bowls and found that the tightening surface of the bowls are very bad. They aren't machined in any way. So I flattened them on a glass plate. Now they are tight.

 

@Roger: If you want to find fuel in the drip trays you need to be very fast. This is due to the temperature and the fast evaporation of fuel :)

 

Blu skies

 

Markus

Link to comment
Share on other sites

Last year I had an issue with leaking carb bowls and found that the tightening surface of the bowls are very bad. They aren't machined in any way. So I flattened them on a glass plate. Now they are tight.

 

 

 

That's the other trick Lockwood gave me.  Lapping the bowls lightly with 300 grit sandpaper on a glass plate, using mineral spirits as a lubricant.  Zero leaks after that.

Link to comment
Share on other sites

So when something doesn't work, the fix is to do more of it?   :giggle-3307:

 

Just kidding.  I think I had another issue along with the gaskets -- my bowl seats were not quite true.  Fixing that is what really cured things.   

Some say: If brute force will not work, use more of it :D

Link to comment
Share on other sites

Wow! Do you prefer the cork gaskets or the plastik gaskets? I had the feeling, that the cork gaskets are tightening a little bit better, if the surface of the bowl is uneven.

 

It is a shame for BING not to machine the surfaces of the bowl. But that's another story.

Link to comment
Share on other sites

I don't care for the cork gaskets which are from the Bing factory. I prefer the composite gaskets. I believe they are a compressed fiber material. I think the cork gaskets are thinner and the others are thicker and allow thee bowl bale to apply more pressure to the sealing surface. (just my opinion) The composite gasket you usually get when you order from one of our service centers. Then I rub white lithium grease on it and especially the sides and work it in. I do not leave any globbed on. Once in a great while I get a carb bowl like Andy's that needs so extra work and not just a new gasket. I do replace gaskets on a fairly regular basis.

Link to comment
Share on other sites

Just be sure if you lap the bowls to do it very lightly.  Too much and you reduce the clamping force of the clip and then you *will* have leaks.  You just want enough to reduce any high spots and blend down to any low spots.  I ran the smallest feeler gauge I had around the bowl on a piece of glass to find where the low spots were.  They were right where I suspected leaking.  I did a very light pass until I saw scuff marks all the way around the bowl, then re-checked with the feeler.

 

Make sure to pour mineral spirits over the sandpaper before you start.  If done dry even 300 grit sandpaper will cut too aggressively, and you might end up with too rough a sealing surface.

Link to comment
Share on other sites

Hi Andy,

 

I just took my handy dandy Dremel and cut down some of the bottom lip on the opening and slightly on the sides. This exposes more radiator to air flow. Most CT's have a small area that is covered by the cowl.

Your temps aren't that high and you may not need to do this.

Link to comment
Share on other sites

  • 4 weeks later...
  • 1 year later...

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...