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Broken baffle mount oil cooler on RV8

ERJDriver

Well Known Member
Doing the first conditional since I bought the ole girl. De cooler it to find the baffling broken on the corner where the oil cooler mouns. 360 angle valve with the oil cooler mounted to the baffling.

It looks like its been strengthened with some angle. Seem to be cracked where it is secured to the number 4 cylinder baffling.

Whats everyone doing to help support it?
 
Here is what I did. Corner, reinforced to the head screw, then a cooler brace to the center of the mount.

Be sure to torque the screws into the head. I had a couple come loose from the feels-right method. The star washers flatten the turn-torque curve well before reaching the book value. I'll look that up and edit. - 96 in-lb - see chart below.

oil cooler reinforcement edited.jpg

Brace to head.jpg

lycoming-torques_zpsd981c236.jpg
 
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Hey, Nice valve covers, Mickey!

I added a doubler to the outside baffel and the bracket on the inside over the #4 cylinder. I honestly think the 45-degree bracket on the inside is the most important. Just install a long bolt on the valve cover that provides the stud to mount the bracket on. I made a little cardboard template and used a piece of 3/8 Chromoly tubing I bought on eBay and then painted it black. If you do a search, you will find several ways to fix this design problem. It seems to happen to nearly everyone.
 

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On my two RV-8s the the oil cooler mount baffle cracked at around 350 to 400 hours. My current RV-8 has a brace from the engine to the aft baffle, and that did not prevent the cracking from occurring. On both RV-8s we replaced the cracked parts and added a skookum angle there (a technical term!). The cracks have not reappeared on either RV-8, and my first RV-8 now has about 2300 hours on it and my current RV-8 has 1165 hours.

Cracks:

i-g7bmgBz-XL.jpg


Fix:

i-3Gx5HZR-XL.jpg



I'm surprised that Van's has failed to address this well known issue that many have suffered from.
 
Thanks Brian - those are some nice valve cover screws you have there - did Ross send you those? I got the Allen heads, which are nice, but not as nice as yours!

Yes, Ross made the covers (they are magnificent, and no more leaking valve covers!). Tim Hess who owns Unlimited Aero Engines built my engine and he used 12-point hardware on everything. The valve cover screws are stainless 12-point 1/4-20 from Specialty-Fasteners. Tim purchased them, but I think they are all 1/2in. except I had to buy a longer one for the angle bracket. The hardware looks beautiful on the entire engine. Of course no one sees it but me! :)

https://www.specialty-fasteners.com/...m?1=1&CartID=0
 
Great ideas, thanks for the pics guys. As I look at them I can telll what I need to add, it’s been braced with angle like all of your but the angle isn’t screwed to the valve cover. So all the load is being place on the top rivet line where the silicone is attached
 
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