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Oil Cooler Mounting

skyking902001

skyking902001

Well Known Member
Need some advice from the wizards! I have cut the rear baffle for the oil cooler and drilled the 705A for nutplates, etc. The lower inboard nutplate is in contact with a cooling fin. If I insert a bolt and get 1 thread showing, it contacts the cooling fin enough to slightly push the baffle to the rear. My question--is it ok to grind a small relief in the cooling fin? If not, looks like I will need to re-order parts and start again in this area. If I raise the oil cooler enough to clear the fin, I am getting real close to contacting the cowl. Thanks in advance. Baffles--blah!

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I don't recall having this problem. Perhaps my cooler was mounted higher?

You say that the oil cooler would be real close to the cowling if you raised it. Well, that is where you want it for best cooling.

I say raise it.

My two...

:) CJ
 
Can not answer your question right now but will be pulling cowl for condition inspection soon and will check it out for you if no one else does before then.
 
Your fine.

skyking902001 said:
Need some advice from the wizards! I have cut the rear baffle for the oil cooler and drilled the 705A for nutplates, etc. The lower inboard nutplate is in contact with a cooling fin. If I insert a bolt and get 1 thread showing, it contacts the cooling fin enough to slightly push the baffle to the rear. My question--is it ok to grind a small relief in the cooling fin? If not, looks like I will need to re-order parts and start again in this area. If I raise the oil cooler enough to clear the fin, I am getting real close to contacting the cowl. Thanks in advance. Baffles--blah!

jfgjsj.jpg
[/IMG]
Click to expand...

Most of us move that inside lower hole not on the baffle so much as on the flange of the cooler. I made a new lower hole up about 3/4 to one inch higher on that side so when it was driller to the baffle it would just clear the jugs fins. There is a spec. in most of the engine makers books to loose a few fins from breakage. Most builders don't like trimming a little off a fin, but if it is done well there is little effect to cooling if it is a small repair sight. On the subject of moving the cooler up a bit, yes we found that if you locate it up as high and out as you can, you can get a 9 row cooler to fit where the Van's 7 row is dawn-up to go by the plans. We have an ECI IOX-360 that the factory spec called out at 191 Bhp., but we worked on it a little and have it up about 2% from there. The 9 row cooler handles the extra heat load very well, even with all 8 oil spray nozzles installed. We found that 3/8" gap between the upper cowl and the top left corner of the cooler was all that was needed. I would do it anyway you like at this point, your on the right track with this one.
Hope this helps, Yours as always, R.E.A. III #80888
 
Your fine.

skyking902001 said:
Need some advice from the wizards! I have cut the rear baffle for the oil cooler and drilled the 705A for nutplates, etc. The lower inboard nutplate is in contact with a cooling fin. If I insert a bolt and get 1 thread showing, it contacts the cooling fin enough to slightly push the baffle to the rear. My question--is it ok to grind a small relief in the cooling fin? If not, looks like I will need to re-order parts and start again in this area. If I raise the oil cooler enough to clear the fin, I am getting real close to contacting the cowl. Thanks in advance. Baffles--blah!

jfgjsj.jpg
[/IMG]
Click to expand...

Most of us move that inside lower hole not on the baffle so much as on the flange of the cooler. I made a new lower hole up about 3/4 to one inch higher on that side so when it was driller to the baffle it would just clear the jugs fins. There is a spec. in most of the engine makers books to loose a few fins from breakage. Most builders don't like trimming a little off a fin, but if it is done well there is little effect to cooling if it is a small repair sight. On the subject of moving the cooler up a bit, yes we found that if you locate it up as high and out as you can, you can get a 9 row cooler to fit where the Van's 7 row is dawn-up to go by the plans. We have an ECI IOX-360 that the factory spec called out at 191 Bhp., but we worked on it a little and have it up about 2% from there. The 9 row cooler handles the extra heat load very well, even with all 8 oil spray nozzles installed. We found that 3/8" gap between the upper cowl and the top left corner of the cooler was all that was needed. I would do it anyway you like at this point, your on the right track with this one.
Hope this helps, Yours as always, R.E.A. III #80888
 
Robert, thanks so much for the reply. Never thought about just raising the nutplate--duh! For the lower nutplate, I plan to use the existing upper rivet hole as the lower rivet hole for a miniature nutplate. This should result in raising the bolt hole by .6", this should be adequate to clear the fin. Thanks again!

Steve
 
Not long ago I installed a 9row cooler on my RV-8. I was only able to bolt the cooler with just one bolt on the inner (right) flange of the cooler. I made a brace to the lower part of the flange from this bolt to regain some rigidity. Didn?t have the idea to relocate the holes on the flange - good idea!
 
There's an easy solution for that problem. If you haven't found a good answer yet, give me a call one evening and I can explain to you how I've delt with the same issue on quite a few RV's.

Rex
530-396-2239
 
R. Daniels said:
There's an easy solution for that problem. If you haven't found a good answer yet, give me a call one evening and I can explain to you how I've delt with the same issue on quite a few RV's.

Rex
530-396-2239
Click to expand...

Share it with the rest of us?
 
I made a standoff bracket using aluminium U channel, rivet the U channel around the perimeter of the cut in the baffling and bolt the oil cooler to the U channel. I also included the oil shutter as my unit was running to cool...
 
Not sure if this will help, but I cut my oil cooler opening a little too high and the oil cooler was interfering with the upper cowl. So, I used 1/8" U channel to construct a little "duct" that moved the oil cooler down and aft a little. As you can see below, it's a very stout setup. Not shown also is a 4130 steel cross brace reinforcing the inner side of the cooler with one of the cylinder heads. I'll take a photo tonight and post it.

IMG_0271.JPG
 
Thanks for that photo Mark! I'm right at this point too. I spent last weekend trimming the baffles to fit the upper cowl and this aft corner is very tight and, I haven't gotten to the 3/8"-1/2" clearance yet; I was worried I might have to move things around to get it all to fit. Looking at your picture it looks like I still have a ways to go...
 
BonitaRV8 said:
Thanks for that photo Mark! I'm right at this point too. I spent last weekend trimming the baffles to fit the upper cowl and this aft corner is very tight and, I haven't gotten to the 3/8"-1/2" clearance yet; I was worried I might have to move things around to get it all to fit. Looking at your picture it looks like I still have a ways to go...
Click to expand...

You just don't have a lot of room in that corner as you want to keep the cooler as high as possible so you don't hide it behind the cylinder, but even at the highest mounting, a lot of the cooler is blocked by the cylinder. By moving it back and down a little, you allow a lot more air to flow and give yourself clearance from the cowl at the same time. Of course, you also need to strengthen that corner and the 1/8" U channel, combined with the 1/8" angle on the forward side of the corner makes it very strong.
 
Offset the cooler

5 days too late for me unless I start drilling out rivets. But the offset idea to get more flow is a great idea.
Not an original idea but effective;
 
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