Modifications: Changed oil cooler SCAT to 5"

Update 29-May-24:  Follow these links to learn about why and how I installed a larger cooler to go with the larger SCAT after I modified my engine to the IO-390-EXP119.

With the new IO-390-EXP119, Van's changed the diameter of the SCAT hose leading to the oil cooler from 4" to 5".  Since I can run 210 degrees on a hot day, I thought it might be worthwhile to swap out to that new diameter tube.  In October of last year, I bought the minimal number of parts to make the swap and reused everything I could.  And I finally got to installing it.

It was fairly trivial to remove the back right corner pieces of the baffle.

 

First the old pieces to be reused had to come off...

 

Then the new CB-00015A Right Aft Baffle could be riveted together.

Then everything gets hooked back up (I cut the excess off of the hose clamps).  I did have to grind away a small corner of the Ignition Wire Harness Seal since it would otherwise overlap a rivet along the CB-00037 5" Flanged Duct.

And here sits that big 5" SCAT.

So what differences have I noticed? 

• I've noticed that the oil temp comes down significantly quicker when I nose over after a climb. 
• I can do a protracted full power climb with 110 IAS in the summer and the oil temp doesn't exceed 210, whereas in the past it would exceed that and I would need to arrest my climb.
• CHTs don't seem to be adversely affected (e.g., perhaps the air going into the SCAT must be coming from somewhere else and either doesn't affect the CHTs or the reduced oil temp offsets any increase in CHTs from reduced airflow).
• Bottom line:  In my case, this modification had a material impact on my oil temp, which was what I was hoping for.
  

FWF: Fuel and Oil System. Oil cooler install.

Fairly easy section.  Most of the challenges come from trying to work in extremely confined spaces.  It's very difficult to properly torque items when you can't get either leverage or room to work within.

The truly hardest part was getting the VA-139 Hose on to the bulkhead fitting coming from the fuel pump.  The only way to realistically do that was to remove the fitting from the firewall, torque the hose onto the fitting, then reinstall the fitting onto the firewall.  I believe VA-139 should be attached to the fitting prior to engine installation.

Oh, I also destroyed an oil cooler.  It was only a $530 mistake, but who's counting?  

The plans state to use aluminum AN822-8D elbow fittings into the Airflow 2006X oil cooler.  However, the instructions for the cooler specifically state not to do that.

Because the cooler is constructed from aluminum, AN822-8D fittings will gall on install, especially if used without sealant (as I did to "test fit" the fitting).  And in fact, that's what they did.  I destroyed the threads on one side after backing the fitting out when it didn't feel right going in.  This cooler was added to my scrap heap and replaced.

On oil cooler #2, I used steel fittings, AN822-8.  They aren't cheap, but they are the right items to use.  And they glide right in since they don't gall.  My replacement oil cooler was much happier.

Looks good.