Oil cooler failure and off field landing in my Zodiac XL

Saturday I decided to fly to Quincy via the Feather River canyon.  I had just dropped into the start of the canyon above an arm of Lake Oroville when I smelled hot oil which was soon followed by smoke in the cockpit.  I was 500 AGL over water and below the ridgelines, miles from landable terrain.


I knew I was losing oil and had limited time.  I did a quick U-turn back toward landable terrain and started a full throttle climb out of the canyon while monitoring oil pressure.  With two-clicks of the mouse I sent an email announcing mechanical failure and asking family and friends to track my progress or lack thereof. The plane flew for 8 minutes before oil pressure stated to drop which just barely got me back to limited areas of flat land.


I could see I was not going to make the Oroville airport, still 10 miles away, and decided to set down before lack of oil pressure destroyed my brand new $18,500 Jabiru engine.  I looked around for a suitable spot and quickly landed. My impromptu runway was at Lat/Lon 39.619994, -121.536816 in a cow pasture.  


I had limited cell phone coverage but was able to send out a text message to family and friends that I was ok.  I knew they could see exactly where I had landed.  They often track my flights via a website I created for that purpose. 


I took stock of the situation and started repairs.  I removed the cowling and removed the damaged oil cooler.  About then a friendly fellow drove up on an ATV.  I explained what had happened and what I was doing.  He offered tools if I needed them.  I was glad to have landed well away from traditional “help”.  The last thing I needed was police cars, fire trucks and hoards of gawkers explaining what I should do next.  Not the kind of “help” I want.


I had a quart of oil in the wing locker and also dumped the oil left in the cooler into the motor.  I started the engine to do a pressure test then put the cowling back on. I hauled the plane up hill by hand a short distance to ensure sufficient takeoff distance.  I walked my proposed takeoff “runway” to verify there were no ugly rocks or ruts.   I returned to the plane and did a classic rough-field take off.


I got as far as Colusa before I concluded that the oil was too hot to make it home to Santa Rosa.  I set down at the Colusa airport where I spent the night.


The next day Doug Dugger of Quality Sport Planes drove to Colusa to help me.  We spent a few hours trying to locate a suitable oil cooler.  We finally picked the best candidate and installed it.  That proved to be quite the chore.  The new cooler was too large to fit in the cowling so we installed in under the airplane.  It worked well enough to get me home.  (Anyone want a slightly used oil cooler?)


The only damage was to my confidence and slight damage to one of the fiberglass wheel pants on the main gear.


All-and-all a good outcome to a dicey situation.  Had the cooler blown out 15 minutes later in my flight the outcome would have been quite different.


By the way, the oil cooler was brand new with only 21 hours on it.  The failure was at the seam.  Obviously it was defective.  The cooler was a TRU-COOL 24 row (L7B) automotive racing oil cooler.  This was the third one I have owned and the first to fail.  This brand of cooler was the early stock cooler on the firewall forward kits sold by Jabiru USA and Jabiru Pacific.  It is black in color.  The original model was a 12 row cooler which I had upgraded to the 24 row model.  Anyone else have a TRU-COOL fail?



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Comment by Stephen R. Smith on May 23, 2011 at 9:02am



The cooler on my plane failed because an oil line was hitting the cowling.  Otherwise I have had good luck with the brand of cooler I have been using on my airplane.  The cooler is made by Tru-Cool.  It is a low-cost automotive-grade cooler.  The cooler is black in color.  You can see a picture of the cooler here.



Comment by Robert Emery on May 22, 2011 at 2:40am


I have a new Zodiac with Jabiru 3300, bought engine 3 yrs ago with oil cooler, started up this week, taxied for fuel calibration and the oil cooler dveloped a major leak, glad I was on the ground. 

My first flight should be (after registration and final checks) in a couple of weeks.  I now need to fit a new oild cooler.  What caused yours to fail, and what did you replace it with.

Mine has no markings, all alumnium pressed



Bob Emery (NSW Australia)

Comment by Rebecca Anne Shipman on April 12, 2011 at 12:50pm
Cool under pressure - great job of handling the emergency.
Comment by Ron Lendon on April 11, 2011 at 10:02pm
Steven, you are going to have to change your middle name to "Sully" for having kept such a cool head. Glad things turned out the way they did.
Comment by Tim Garrett on April 11, 2011 at 9:28pm
Stephen, I just want to echo everyone else's comments. Your cool calm rational response is a great example of awsome piloting. Of course it could have been worse but you kept your brain engaged. Your tracking system paid off, too.
Comment by Stephen R. Smith on April 11, 2011 at 9:16pm

Thanks very much for the kind comments.


I am quite sure that firewall forward kits shipped in the past few years do not have the black TRU-COOL oil coolers.  I understand the newer coolers are un-painted aluminum.


My confidence in my Zodiac airframe remains unshaken.  I have tested it thoroughly.  I have had issues with the Jabiru engine, but non that caused me to worry about getting home.  The cooler that failed was not supplied or endorsed by Zenith or the Jabiru factory.


As to the on-field repair: What I did was remove the sandwich adapter under the oil filter and I fit the oil filter directly to the engine.  Note that on newer Jabiru motors you would NOT be able to do that out in the boonies because the attachment “pipe” for the oil filter is in one-piece where as on the earlier engines there is an extender fitted to the “pipe” coming out of the block.  It is true that I have a new motor which came with the single “pipe” setup; however when I installed the engine, I changed that back to the two piece setup when I added the thermostatically-controlled sandwich adapter in place of the stock one.


So far the oil cooler failure is a bit of a mystery.  For now I am assuming it was defective and have ordered another one.  I have been dreaming up a way to pressure test it overnight at say 150 PSI before putting it into service.  My basic idea is to fill it with water and then use compressed air to pressurize it; just need to work out the fittings.



Comment by STEVEN and TARA SMITH on April 11, 2011 at 3:59pm
Stephen I always enjoy your travel stories. Thank God your safe. You’re an inspiration.
Comment by Phillip Owens on April 11, 2011 at 3:17pm
The oil cooler that failed on me was also supplied with the engine from Jabiru USA it wa an all aluminum K&J cooler. Not only did the center tube expand but it blew a hole in one end and spit oil all over. Replaced it with a Positech unit of much higher quality. Glad you didn't have any more problems that you did. The oil samples that were sent in came back without any indicated engine damage. ope you have the same luck.
Comment by Bill Pagan on April 11, 2011 at 3:12pm
Good job Steve.  Only hope that I can handle such a situation as well and hope even more that I never have to.
Comment by Alberto Martin on April 11, 2011 at 12:43pm
It´s great to know you are ok, nobody injured and the plane also ok is allways great news !

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