Help locating my Oil Leak (photos) or is it normal?

[Ragsf15e]

Hello - 

 

I know lots of our IO-360s leak a little oil, and mine's not too bad at 5.5 hours/quart, but I wouldn't mind a few thoughts on where to start looking based on the attached photos.

 

It's been leaking about the same for the last 6 months (when I got it).  I just got back from a long cross country this weekend and took these pictures today before cleaning it up.  After any length flight, there is oil streaming back on both nose gear doors and it appears as if oil comes out from the panel just below/behind the oil cooler on the left side and streams back toward the wing root (where I also clean off oil).

 

I only keep it between 5.5 and 6 quarts, so I know it's not overfilled.  I've had a mechanic look at it during the last oil change with nothing found.

 

Thoughts?  Should I just not worry about it?

 

Thanks!

 

Drew

[Mark Lenker]

Drew

Remove those side cowling, take some more photo's and let's have a closer look. I think that I can help.

Mark

[carusoam]

Welcome aboard Mark.

Rags, there are many places that oil can leak from.

Most are low cost fixes...

Others are horrific in comparison...cracked cases and the seal between case halfs come to mind...

All should be corrected if possible...

My O360 leaked from the oil return hoses from the valve boxes and from the valve cover seals.

Anything with a hose clamp on it needed to be replaced over time...

Good luck with you search.

Best regards,

-a-

[Danb]

I like Anthony had leaks, unfortunately on my 88 J in 1989 it was leaking similar ,luckily under warranty it was the seal between engine halfs. Mine went back to Lycoming for the fix..as Drew said post some pix where it s and appears to start. My have to wash down engine and take pix right when it appears...

[Releew]

Check the oil crossover tubes/clamps.  I recently changed the gasket at the bottom of the oil fill tube as well.  These were my main two areas of leakage and are common on the IO-360.

 

Rick

[robert7467]

Mine was leaking from the back of the oil pan. Took me 4 years to find it, but by tightening the 4 bolts in the back of the pan fixed it. They are very hard to get to. It took 2 hrs with a flexible extension to get to them. Also look at your return tubes and see if they are rubbing against any baffling. A little pinhole can cause a serious leak. Since those lines have no pressure they can be brazed.

[Ragsf15e]

 Ok, I'll take it apart on Thursday (gotta work tomorrow  ) and I'll take some pictures of the inside.  

 

I'm guessing it's going to be kind of a mess in there so I may have to clean it out and try this right after an hour flight to see if I can see where it's coming from.

[robert7467]

You can use avgas or kerosene in a sprayer. I prefer avgas, or you can use real gas. But kerosene will not dry rot the seals in the sprayer as fast, but it's more volital.

[robert7467]

Forgot to mention, after sprayed thouroughly, run at a low rpm for 5 to 10 mins. If you run it fast, it will just blow oil everywhere making it hard to pinpoint the leak.

[carusoam]

The good cleaning can be followed up with two other methods to identify the leak's source...

UV ink in the oil, using a black UV light in a dark hangar to find it...

Something like talcum powder to try to find the wet spot...

I have absolutely no experience on how these work...

Check with your mechanic for details.

Best regards,

-a-

[rbridges]

Mine was the prop governor ...

Took a little while to make sure that was it. Overhauled the governor, had residual oil still coming out (although we wiped it clean afterward) for several afterward. Installed an M20 Oil Seperator not long afterwards (Yes, I was tired of cleaning the belly!) and now it is next to nothing!

 

how much did the separator cost with install?

[BigTex]

Ok, I'll take it apart on Thursday (gotta work tomorrow ) and I'll take some pictures of the inside.

I'm guessing it's going to be kind of a mess in there so I may have to clean it out and try this right after an hour flight to see if I can see where it's coming from.

Rags, based on your comments, I sense that you don't take your cowing off much. If that's the case, you really need to get it off and get it cleaned up. That way, you'll have a better chance of finding the leak. You might want first try tightening up the valve covers. Mine leaks from there from time to time and it's about a five minute job.

I'm a little OCD about keeping my engine clean so my cowl is off all the time. It is also a good idea to give the engine a good look every few hours.

[helitim]

"You might want first try tightening up the valve covers. Mine leaks from there from time to time and it's about a five minute job."

Be careful about over tightening the valve covers though. If I recall correctly, the torque was a very low number. Something on the order of 20 inch lbs. Not sure on the number but, it was surprisingly low.

Tim

[Bob_Belville]

I take the cowl off often. You don't have to be a mechanical genius to see stuff that ain't right. In addition to oil leaks, look for chaffing wires and SCAT hoses, loose bolts (the valve cover bolts seem to back out 1/4 turn or more every 10 hours). I make sure the hydraulic reservoir is topped off every few months. Check tire pressures. Even lightly flown planes need some attention between annuals.

[Ragsf15e]

Gary - You're right, I don't take them off much... or ever.  I do have my A&P look over the engine each oil change (35-40 hours), but I should definitely get in there more.

 

I agree with Bob too - there are probably obvious issues that can be seen/fixed by other than an A&P.

 

Thanks for the inputs.  I'll definitely go take it apart and work from there.

 

Rags

[Ragsf15e]

Ok, I took the cowling off both sides and took photos.  There is a dark blue fluid coming out somewhere around the gasket on the valve covers of the #2 and #3 cylinders.  It feels like oil and doesn't smell, but it's blue!  Could that be the oil?  Why is it dark blue?  Is it somehow mixed with fuel?

 

The inside of the cowl on the left side even has a blue stain on it (see photo).  

[BigTex]

Looks like an induction fuel leak to me.  What's your EGT/CHT's for your #2 cylinder?

[DonMuncy]

The blue is certainly fuel. You may have some oil leakage that is covering the fuel stains.

[Marauder]

Ok, I took the cowling off both sides and took photos. There is a dark blue fluid coming out somewhere around the gasket on the valve covers of the #2 and #3 cylinders. It feels like oil and doesn't smell, but it's blue! Could that be the oil? Why is it dark blue? Is it somehow mixed with fuel?

The inside of the cowl on the left side even has a blue stain on it (see photo).

Rags -- when I blow up your first picture, I see fuel staining on the baffling above. If it were just an induction leak, I wouldn't expect to see fuel in front of the induction tube.

I would pull the top cowling and look for a leak around the injector and the line going to that cylinder. There is an AD on our injector lines. Has that been complied with recently? Supposed to be done every 100 hours if I recall correctly.

[Mark Lenker]

Rags

You have some problems on the #2 cylinder, do not fly this until fixed……here's my suggestion….if you look at photo 1 very closely you will see fuel stained/pooling above the #2 intake tube flange, keep looking higher and make sure that the #2 fuel injector/line is not leaking….if not then replace the #2 intake tube attach flange gasket, be sure the intake tube is seated correctly in the intake tube flange when re-installing the intake tube and torque the 1/4" attach bolts. Let me know if this helps….also you only showed photo's of the #2 cylinder, is the #3 the same? 

Mark

[Ragsf15e]

I have GAMI injectors, so wasn't aware of an AD recurrent inspection, but will definitely check out the injectors either way.

 

#2 and #3 cylinders both run very nice temps in cruise.  Low 300s for CHT and somewhere around 1300 during climb, 1400ish LOP cruise.

 

Here's one more picture from the top of #2.  Not as clear as the ones below, but looks like some blue staining to me too.

 

I'm going to have it thoroughly checked out.

 

Thanks for the replies!

 

Drew

[Ragsf15e]

Mark - 

 

Yep, #2 and #3 look about the same.  I didn't get the top cowling off yet, so can't clearly see #3's injector, but it looks just like #2.  One of the 3 pictures on the previous page is actually #3 cylinder, but pretty close up and hard to tell.  Definitely fuel there.

 

Thanks for the input guys.  I won't be flying it until we get it sorted out.

 

Drew

[Mark Lenker]

Drew

Here's what I think you should do, first off the AD is only in reference to the fuel line injector lines clamping and supporting, gami or lycoming injectors doesn't matter. Now start from the top down, remove the #2 injector, clean and install, torque correctly, re-install the injector line and you will now have to comply with the AD on the injector line, please reference the AD, now change the intake tube flange base gasket, spray some soap/water mixture on the exterior of the #2 cylinder in the affected area to verify no cracking, clean all of the fuel stains and perform a ground run. Now, this thread started with an oil leak on the right side nose gear door, everything that has been discussed from all members will not address this oil leak from the starting of this thread, so it's safe to say you still have the oil leak. I lope this helps.

Mark 

[Ragsf15e]

Mark - 

 

That definitely helps.  I'll be looking into the AD and going through the steps you mention this weekend.  I looked back at my last annual (Maxwell Avn) and they complied with the AD in June, but I'll double check it since I'll have it apart.

 

Copy all on the oil leak... it may still be there, but I'm really glad we caught this because it seems much worse than a few drops of oil on my nosegear doors!

 

Drew

[Marauder]

Drew -- that last picture sure makes it look like it is coming from the injector area. I believe this is the latest version of the AD: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/37c75db7f83d5d548625796d00529e4f/$FILE/2011-26-04.pdf

I try to get it complied with every other oil change to prevent not going over the 100 hours between annuals.

Let us know what you find out (I'm betting either the GAMIs or fuel lines weren't torqued all the way to specs). Hopefully an easy fix.