Oil Cooler Mounting Question - RV-9

[JVolkober]

I am at the point of mounting the oil cooler. Baffels are fitted and cut down to size. I drilled the CB-705B oil cooler brace to the baffel placing it such that I can get the oil cooler mounted as high as possible. Now I find that I need to cut the rear most flange of the oil cooler to clear the engine mount right where the center mounting hole is located, one of two available to attach the cooler to the baffel. This would negate the use of the long bolt and spacer at this point. It appears that the solution is to use a shorter bolt that would secure only the inside flange (the flange sits against the baffel) to the baffel. Is this an acceptable solution. Is it ok to just use the inside flange only to attach the cooler at this point.

[Vlad]

Jonh,
I think it's common mistake and builders will post their solutions here.
I made the same miscalculation last year while installing the cooler. I asked several experienced guys about that at Oshkosh and they said it's acceptable to use short bolt on inner flange. I decided to use longer bolt for now, just removed the spacer and have the clearance about 1/4 from the head to engine mount. I will see after engine start if vibrating oscillations are large enough for bolt head to touch the mount. If it touches I put short bolt then. Also I was thinking of making a modified bracket from aluminum angle to attach to outer flange. The idea was to use the same flange and 25% shorter bolt to bypass the mount. Decided against it will see how it vibrates.



Spacer is already removed and clearance about 1/4.

[Brantel]

I used a short bolt on the top inside flange and the long one with the spacer on the bottom one.

I suggest putting in the diagonal brace that lots of people put in from the start.

I also suggest putting a piece of rigid angle in the outside corner of the baffles from the get go.....

I have already developed a vertical crack (@25hrs) in the outside corner of the new style baffles. There are just too many close spaced holes in this corner and the cooler must move around alot!!! Do yourself a favor and go ahead and install the angle and brace or you will be doing it later! ( I know someone will get on here and say they have ???? # of hrs and have no cracks and never beefed anything up, great for them )

[robertahegy]

Vlad, That looks very good, but I would recommend placing washers between the spacer tubes and the cooler flanges to prevent chaffing. Builders should be wary that the corners of the baffles are contoured to the cowl to prevent damage from engine rock during startup and shutdown. The cooler can get beat up if the clearance is too tight.

Roberta