Rear baffle oil cooler

[chopper12]

Hi
Would anyone have a couple pictures of their oil cooler mounted on the baffling behind # 4 cylinder.

THANKS

[Gilbert Pierce]

The attached pictures were taken while my engine was off for the fuselage restoration. Behind the aluminum angle on the rear of the #4 baffle is a 0.040" 4130 steel angle as we had cracking in the aluminum angle.

That nose gear engine mount is not mine. Mine was off getting powder coated which was a bad idea.

The cooler was origninally mounted on the rear baffle as the RV6 is without the extended piece. I had high oil temps and modified the baffle to provide a plenum for the air. Didn't help. Sealed around the air intake on the bottom cowl with a leather seal as per the Piper drawings and solved the problem.





39523953

[chopper12]

THANKS Gilbert
Gilbert does it matter which oil line goes to which outlet on the cooler?
THANKS

[Gilbert Pierce]

Normally you would put the hot stuff in at the top and as it cools it naturally flows to the bottom ala Ford model T radiator with no water pump. With 75 psi pushing the oil and about a 8 degree difference from in to out I doubt it makes a difference. I just plumbed the top cooler outlet to the top engine connection and bottom to bottom because it was easier. Turns out the hot oil is going in at the top and cooled oil out at the bottom- I think!

[dcflyer84]

Gilbert,
Any chance you could send a link to the Piper drawing of the air cooler leather baffling? You may have posted that in another forum but I couldn't find it again. Thanks!

[Gilbert Pierce]

I could never find the baffle in the SWPC drawings. I came across it in the Piper Pace PA-20 Parts Catalog from Univair.
In my catalog it is on page 146, Power Plant Installation item #5 part-number 11950-04 and is applicable to all models of PA20 and PA22.

I purchased mine from Univair probably 10 or 11 years ago. They do not now list it online which doesn't mean anything. The part I purchased from them was leather as called out in the parts catalog.

With age it got old and stiff and did not seal. I have since made one from silicone baffle material. I cut it out of a square piece of material. The inner square hole is the same size as the airbox inlet. The outer dimension overlaps the airbox opening by about an inch on all 4 sides to provide the air dam.

This same seal is used on the Continental Powered Super Cubs. I assume that would be the PA-18-90
Attached is a picture that only shows the edge of the leather seal clamped between the air-filter and the carb inlet box.

[dcflyer84]

Many thanks, Gilbert! I found it in my Univair parts catalog as you indexed for me. I'll see about ordering one from them. at least I'll have a pattern to use if the one they send me wears out over time. Looks like a pretty simple install/fabrication. Might just make my own with the silcone baffle material like you have done. Peter Lubig showed me a photo of yours when we was down looking at my Pacer last week. Had good things to say about it, and it's a cheap improvement--I like it!

[chrisg]

At some point I came across a diagram for mounting the oil cooler on the baffle, but I didn't save it. Does anyone happen to have a drawing of this installation and/or can you tell me how big the hole in the baffle is supposed to be?

Thanks!

[Steve Pierce]

Depends on the cooler used. Stewart brother of Stewart System fabric sysyatem have an STC. The hole is as big as the opening in the cooler for air flow.

[pa20]

Since this is in the experimental section, I will also suggest that you install the oil cooler shutter that Van's Aircraft sell for the RV series.

[Vagabondblues]

I have always wondered, since our aircraft with the rear oil cooler seem to run cool, why not drill a bunch of 1/2 inch holes in the area of the cooler inlet instead of regular opening? You could start out with drilling a symetrical pattern for the holes and leave a few undrilled. As you flew the aircraft and found the operating temperture of the oil, i.e., too warm you could add another hole to the pattern until you regulated the cooling air over the cooler.

Todd

[pa20]

Here is the quicker, and more definitive fix!
http://www.vansaircraft.com/cgi-bin/store.cgi?ident=1410293157-134-405&browse=engines&product=oil_shutter

[mmoyle]

Here is the quicker, and more definitive fix!
http://www.vansaircraft.com/cgi-bin/store.cgi?ident=1410293157-134-405&browse=engines&product=oil_shutter

What can be used to regulate the oil temperature on a certified aircraft when the oil cooler has been moved to the rear baffle using the Stewart's stc? Is there a vernatherm valve that can be added to the oil filter adapter? Or is this Vans part a good legal option?
Mark M.


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[PACERGUY]

Mark
I just use a thin pice of aluminum slid between the front side of cooler and baffle. Bend a lip on top so you can slide it up and down to adjust temp. Narrower pice for spring only covers half of cooler. You may have to use thin washers between baffling and cooler to make space. I have a vernatherm (pulled, checked, replaced,) It did not do much.
DENNY

[mmoyle]

Denny, I purchased the Van's oil cooler plate...thingie... Had it on the front side of the oil cooler...blocked air flow. Mounted it in the back side with a spacer...motor mount goes there... Thinking about making a 1/4" thick aluminum spacer plate and mount it to the front side of the baffle...then that plate....will be cockpit adjustable....for now I'm going to continue to sniff fumes....then hang the engine and address that oil cooler temperature control issue...


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[PACERGUY]

Mark
Will that thing block of the air flow completely? It looked like a nice rig. My problem is when it is hot and I am pushing hard I need all of the cooler exposed, but when it gets to zero and below I need to block it off all the way. My wife says I need some cheese to go with my whining.
DENNY