J

Joe

Well Known Member
Can someone point me at a photo of a firewall-mounted oil cooler installation?

Thanks,
Joe
 
Here's one I helped a friend make for his RV-7A.

You can secure the cooler to the firewall with two pieces of aluminum angle with plate nuts on the inside. Then simply slide the cooler in place and secure with AN3 bolts.

We used Styrofoam and clay to form the mold and then laid the fiberglass up on it. The next day we bolted it in place and went flying. It was really easy to form the diffuser so it would avoid the engine mount.
 
Here's how I did mine

100_1802a.jpg


Note that it is patterned after Van's RV-10 cooler mount, but the angle is different. The face is set to be parallel with the engine mount of the RV-8
 
Last edited:
scsmith said:
100_1802a.jpg
Click to expand...
Now that's what I was looking for, Steve -- thanks. (Excuse me but the '8 is different from the side-by-sides and Google search turns up mostly noise and little signal.)

So you came off the baffle behind #3 -- good, more room. Is the plenum needed for airflow or could the flange Vans sells be used instead? Is that 3- or 4-inch SCAT tube? Any provision for closing it off in cold OATs? And how well does it work/anything you would change? Did you ever see so many questions from someone who only wanted a picture? :) Thanks again.

--
Joe
 
things I would do differently, and would do the same

Hi Joe,

The scat is 3.5" -- I figured I would split the difference. There is a butterfly valve (like a throttle plate) mounted in the flange on the back of the #3 baffle -- you can just see the pivot nut, and the control cable going up to the far side in the picture.

How does it work? First, I have the IO-360-A1A angle-valve engine with piston squirters, so there is more heat load put into the oil.
The temp control works great. In the winter, cruising, I have it about 2/3 closed. In the summer, it is wide open all the time. On a warm day, it will cruise with oil temp about 175F--180F.
On hot days, like 95F on the ground, If I take off and climb straight to 10.5K at 115 kts, the oil will get to about 220F. This summer I made a fuel stop in Wells, NV in the mid afternoon. It was almost 100F on the ground, field elevation 5700. The oil was already hot from cruising for 3 hrs. I climbed at 125 kt straight to 12.5K and the oil reached 230F. That's the hottest I've ever seen it. 15 minutes of cruising and it was back to 195F.

To do over again, I think I would use 4" scat. The 3.5" has only a little more flow area than the cooler, so I am getting some pressure loss. Some people think the angled plenum is bad, but the flow is slow in there, and there is very little pressure loss -- the wedge shape helps force uniform flow through the cooler (it can't just all pile up at the end).
I also notice that the way the Niagra cooler is made, there is some leakage out the sides, so some flow escapes without going through the cooler. I want to seal that up.

All and all, I am very happy with it and would do it again. If there was a place that it could be located where the engine mount tubes would not interfere, it would be cool to put a fiberglass diffuser on the exit to slow the flow down, this would increase the flow velocity through the cooler. But my firewall was already full of other things, so this is where it needed to go.

Oh, and say hi to Bruce Patton for me - a new neighbor of yours :)
 
Last edited:
More good info, Steve. Thanks. I like it and will do the same for my IO360-M1B.

Alas, I haven't met Bruce Patton yet but will mention you when I do.
 
Air control valve for oil cooler

Joe and others,
If you use 4" Scat, there is an available butterfly valve for controlling the flow into the oil cooler. It saves you having to make your own.

Look here:
http://www.nonstopaviation.com/rv10-controller-cooler-p-14566.html

On the other hand, I made mine integral with the flange attachment on the rear baffle, which was really handy. I simply turned a couple of steel bushings on a lathe, pressed them into the duct tube, made a 1/4 stainless steel shaft with a flat on it for the butterfly valve, and put a lever on one end.
 
air supply for cooler?

Vince,

Do you have a separate air scoop on the top of the cowl that supplies air to the cooler? If so, that is a very nice, tidy solution.
And I assume you have a plenum because I don't see any baffle seal material on the baffles.

vfrazier said:
This set up works quite well on my Rocket. Not shown is the butterfly valve that was installed in the opening, or the cover which was removed for the photo.

center mounted oil cooler

finished%20oil%20cooler.jpg
Click to expand...
 
Steve,

No, there is no external inlet. The air comes off the back of the plenum. The opening is about 2"x8" (estimated from memory) and has a butterfly valve in the throat to control airflow.

The oil cooler has a simple aluminum cover over the top and flexible baffle material between the solidly mounted oil cooler and the engine plenum.

Typically, I have trouble keeping the oil warm enough. That's why I added the butterfly valve. Only on 95F days while doing touch and goes will the oil temps ever go over 210F.

N540VF plenum

IMGP4761.JPG
 
Last edited:
Which cooler do you have?

Vince,
that is a very nice arrangement. What cooler do you have. It looks BIG.
 
I can't recall which oil cooler I went with. Probably whatever Mark Frederick was recommending back in 2002. It's not unusually large, but might look that way since it's buried under the plenum goodies.

Oil filter changes are no different. It is easily accessed by reaching under the oil cooler. I might even argue that this set up makes access to the back of the engine easier. I can readily adjust the mags, oil filter, etc.

It does block the tach drive, IIRC, but you don't need that with the GRT stuff anyway.

The main reason I did it this way was that the oil coolers that hang off of the baffles seem to have lots of cracking problems with the mounts and baffles. I even had an oil cooler itself crack on one of my planes, years ago.
 
You must log in or register to reply here.