Going out for my second sortie and while in the climb with full power I got that hot oil smell and a bit of mist in the cabin.  Closed the heat control valve, reduced power and "bee-lined" to the airfield with good oil pressure while venting the cabin. Taxied in with good oil pressure to a shutdown in front of my hangar.

What a mess...I was down to just below the min line on the dipstick.  Luckily I have another oil cooler (AERO-Classics) on the shelf which I've been meaning to put on since this summer.  I've heard bits and pieces regarding the quality of the UL provided oil cooler and wanted to see if a different cooler might help out with cooling (and quality?)  Anyway, something to think about I guess...

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Wow!  You haven’t had the best of luck with oil issues.  Glad you made it back safely and no

damage to your engine.

I thought I was pretty lucky...only a couple miles from the runway.  Could have been sitting on a snow covered frozen lake somewhere!   


Very glad you made it down ok and had no damage.

Did the leak come from the oil cooler?  Can you tell where it came from?  This was the UL cooler that came with the engine?

Sorry, I just wasn't understanding your post clearly.

Perry, yes that was the original UL component that came with the engine.  I will be replacing with the AERO-Classics 13 row I got from Ray Lawrence last year.  The failure or leak is internal to the cooler.  Time permtting I will conduct a pressure test and then a destructive investigation ;)

Very sorry to hear this, David. You are having wayyy too much trouble keeping oil inside the sump lately. Thanks for letting us know. I too have heard bad things about the supplied cooler and my oil temp has been high during the last couple of runs. Is your other cooler the one that Ray offers? Good job getting her back in the barn.

Tom, I would "suggest" that you strongly consider replacing the original UL supplied cooler at your next oil change.  I just finished talking with Ray (where I got the AERO-Classic cooler) and he just does not like the (lack of) robustness of the original cooler.  Likely will not solve any cooling issues if overheating is an issue, but it will most likely last a fair bit longer.  Interestingly, AERO-Classic reps say you don't need the rubber shock mounts at the four points of attachment to the cooler.  I would have been inclined to do so -  guess that saves a bit of work anyway!

Hope to be flying next week and keeping the oil where it belongs!  Cheers...Dave

David, I purchased that same cooler from Ray last Fall, but decided to wait and install it when I do the condition inspection in April.  Looks to be a little bit of a job adapting the cowl to fit and I’m hoping the existing hoses will still work. Your work always looks professional and hope you will put pictures on here when you are done.



Interestingly, AERO-Classic reps say you don't need the rubber shock mounts at the four points of attachment to the cooler

That's good to hear, Dave.  I originally had a 7-row Aero Classics cooler on my Jabiru 3300.  The Jabiru FWF kit instructions specified rubber tubing sleeves over the mounting bolts to act as shock mounts.  Looked like this:

Later, I upgraded to a 10-row Aero Classics cooler and to gain additional mounting space so the cooler wouldn't touch the cowl, I deleted the rubber shock mounts.  I rationalized that since the 6 cylinder Jab was such a smooth, vibration-free engine, they really weren't necessary. It appeared to me that the rubber tubing and longer bolts (the spacing downwards by the longer bolts was necessary to align the 7-row cooler with the cowl opening, but not necessary for the 10-row) provided a pendulum effect that could amplify vibration while solidly bolting the cooler-side mounts against the engine-side mounts would eliminate any amplification.  So, to me it appeared to be "six of one and a half dozen of the other." 

I kept a careful eye on the mounting, looking for cracks or leaks, but never had a problem and have put on many 100's of hours since then.  If the Aero Classic reps made any other recommendations or tips, I'd be glad to hear them!



Yikes! Good to hear both you and your aircraft are alright tho...

Glad you made it down safely.


Your pictures are providing me with the motivation to get the new AERO cooler installed in my bird! I ordered the new cooler due to high oil temps in last summer’s heat and as the outside temp dropped, so did my motivation. At the time I ordered the new cooler Ray inferred that there had been some failures of the original coolers and that a change up was not a bad move. The AERO cooler has more capacity and is expected to take care of my heat issue. My temps in my Cruzer were 220 and climbing on hot afternoons. Running the 350i.

Question about install, how much cowling is required to be removed? Is this a palm sander job or is it a vibrating trimmer job?




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