What's new
Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

Oil Leak from Sensor/device right above oil filter.

F

Frankmali17

Member
Hello RV Pilots. On a recently purchased RV-7, with a Lycoming o-360-A1D... i have an oil leak I am not sure how to best handle.

I am going to attach a picture, hoping that someone here will recognize what I'm talking about right away.

Above the oil filter, is a tach sensor/sender.. .I think. and it looks like oil is leaking out at the connector or back of the black cylinder..., not where it goes into the accessory case on the engine, where the silvery thread cap is. I think this is what give the tach signal to my Dynon D180 ?

This causes oil to leak and drop onto the filter... then gravity makes it run down the side of the filter.. and eventually drips/blows onto the firewall and hoses/wires/things bellow.

Is this something pretty common? Should I contact Dynon for such a sensor? or Can someone point me to where I should look for one?


Thank You in advance...
 

Attachments

  • IMG_1333.jpg
    IMG_1333.jpg
    2.6 MB · Views: 215
  • IMG_1334.jpg
    IMG_1334.jpg
    1.7 MB · Views: 213
Carl Froehlich said:
Hard to tell but it looks like oil weeping out of the crank case breather house.

Carl
Click to expand...
Thanks for the insight.. but I wiped it all down, went for a 1 hour flight... and then I could see droplets of oil hanging from the black cylindrical part.

I think this is a UMA tach sender originally set up for the mechanical gauge... I don't know though, if the D180 is connected to it also
 
The D180 usually gets its tach signal from the mag or EI pulse. RPM is a set up in the menu. That is a rpm sender and rotates off the accessory gear box and was used in times past for tach , hobbs meter and etc. but not sure how being used there. Maybe disconnect it and see what quits working! Mine has a cap on the case and not used. Maybe left over from older instruments and no longer used.
 
One of my techniques to find where oil is leaking from is to wrap the area of concern with part of an old white t-shirt zip tied to the item. Go fly an hour or two and then check the t-shirt. This will rule out drips from the blue breather hose above.
 
RV8Squaz said:
One of my techniques to find where oil is leaking from is to wrap the area of concern with part of an old white t-shirt zip tied to the item. Go fly an hour or two and then check the t-shirt. This will rule out drips from the blue breather hose above.
Click to expand...
I like the technique wrap the suspect oil leak with a paper towel and then over that wrap guerilla tape. Fly for a while and next oil change unwrap and see if the pad is oil soaked. Same idea.
 
Disconnect the tach drive unit from the engine. The drive shaft in the engine should be dry. If there is oil there, which I assume there will be, replace the tach drive seal. Be prepared its a SOB to get out. Don't know if the the tach sender itself is effected with oil passing through it but unlikely if the tach on the d-180 is working. Good Luck, Mahlon
 
mahlon_r said:
Disconnect the tach drive unit from the engine. The drive shaft in the engine should be dry. If there is oil there, which I assume there will be, replace the tach drive seal. Be prepared its a SOB to get out. Don't know if the the tach sender itself is effected with oil passing through it but unlikely if the tach on the d-180 is working. Good Luck, Mahlon
Click to expand...
I think we need some clarification, should read: remove the tack generator from the engine ( the tack drive stays on the engine), replace the tack drive seal (with the tack drive in place on the engine).
 
I'm all for fixing oil leaks. That said a big ol fat "it depends" is called for. Specifically upon how much oil is leaking. I have a bit of oil on my engine and belly but can go many hours without adding any, thus tough to get too exotic to chase down the leak.
 
BoydBirchler said:
I think we need some clarification, should read: remove the tack generator from the engine ( the tack drive stays on the engine), replace the tack drive seal (with the tack drive in place on the engine).
Click to expand...
Sorry for the confusion by Tach drive unit I meant the tach generator as you suggest. Good Luck, Mahl;on
 
RNB said:
I'm all for fixing oil leaks. That said a big ol fat "it depends" is called for. Specifically upon how much oil is leaking. I have a bit of oil on my engine and belly but can go many hours without adding any, thus tough to get too exotic to chase down the leak.
Click to expand...
Some people are less tolerant of leaks than others. And just a few ounces will make a complete mess of things. If one doesn’t resolve leaks as they occur, two or three “minor” leaks will make it very difficult to chase down and fix.
 
Hey Guys thank you for the input. If my dynon d180 gets it's tach sygnal from the mags... and this one only drives the mechanial gauge on my far right, that I don't tend to look at... with that said, could I just remove that UMA magnetic tach sender? Could I put a cap and a o-ring over it? It is kinda in the way when trying to remove the oil filter... is there any engine damage risk if it is removed?
Thanks :)
 
Please be aware the tach cap does NOT keep oil in, it is a dust cover. You will need to put a new tach drive seal in the accessory case.
 
William said:
Please be aware the tach cap does NOT keep oil in, it is a dust cover. You will need to put a new tach drive seal in the accessory case.
Click to expand...
So what is the O ring for.... There is no reason why this cap can't seal the drive... even if you need to make a flat seal in the cap.
cap tach.jpg
 
With the photo magnified, it looks more like a small hole in the oil filter itself -- sometimes people do this with an ice pick to drain oil from the filter before removing it. Or, maybe, it's simply an optical illusion. Normally, oil doesn't leak from the mechanical tach drive port.
 
William said:
The tach drive will not leak oil without the cap on it as long as the tach seal in the accessory case is intact
Click to expand...
True. But if the tach seal was bad and leaking, this cap with a proper seal (O ring or gasket) SHOULD keep the drive from leaking and never require the tach seal to be replaced...
 
You must log in or register to reply here.
Back
Top