Oil Cooler

[R Strahm]

I have a BC12D-4-85 that has oil temps of 210+ when I fly in 110F weather. Has anyone installed the Continental factory oil cooler or a remote oil cooler with good results?

[3Dreaming]

Re: Oil Cooler

As a rule of thumb I've always heard 100 deg. over ambient temperature for the little Continentals. I think I would try a F&M oil filter adapter, with a blast tube on it. You might also be able to get a field approval for a cool can wrap for the filter. This way you can help cool your oil while filtering it at the same time. Tom

[barnstmr]

Re: Oil Cooler

Start with the basics... Check the condition of your rubber baffle seals to make sure they seal up against the cowling. And then check to make sure your lower baffle faring (below the crankcase) is properly installed. Check the cowling exit to be sure it is clear and properly shaped. Verify no exhaust leaks. Cylinders have good compression? Oil quantity full on each flight? Ignition timing correct? Maybe you've already considered these... they can make a big difference, expecially if more than one of these items is not right.

[NY86]

Re: Oil Cooler

The oil filter kit is good for about 10 degrees. The filter cooler arguably doesn't require a field approval as it's not permanently attached...

The Continental oil cooler kit is very rare, and there are no other certified alternatives I am aware of.

You can add a 1" blast tube blowing on the oil screen housing for another 10 degrees or so.

That said, the engine is certified for a max temp of 240 degrees. This means that you can operate all day long at 240 without doing any damage. (Not that you'd want to...) Of course, the oil life is reduced by extended operations at elevated temps.

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[VictorBravo]

Re: Oil Cooler

Get a roll of aluminum foil and crumple up pieces of it as if you were wadding up newspaper. Work, shove, poke, and push these pieces into all the little gaps between your baffles and your engine/cylinders. Plug up all the gaps, top and bottom, on the sides of the crankcase and especially where there are gaps between the bafflign and the cylinder fins.

Now before someone gets all bent out of shape, this is a test flight.

Bend the ends of the aluminum foil plugs so they CANNOT wiggle out of position and get fouled up in something !!!

Go test fly the airpalne and see if that made any significant difference. If it does, then you have to remove all the alum. foil and tighten up your baffling, at least knowing what you will get for your troubles.

I found out the hard way that the aluminum baffle under the crankcase, which gets sandwiched between the intake spider and the case, is VERY important. You want all the air you can get flowing through that chamber. THAT air is what cools your oil as it flows back down the crankcase to the oil pan.

A little STP in the oil will make the oil do better in the heat, however STP is thicker so it will run a touch hotter. IMHO it is worth the trade.

A big deal on many old airplanes is that the baffle rubber seals do not seal against the cowling, as mentioned by someone else. This is the first palce you should look, and you will need inspection mirrors, flashlights, etc. to do it right.

Bill

[Joel Severinghaus]

Re: Oil Cooler

My Continental 65 is also running at 200-210 degrees these days. My nosebowl, however, is missing the angled scoop riveted in the rectangular opening below the propellor (see attached photo of someone else's plane), so I'm sure I'm missing some cooling air around the lower half of my engine that way. Baffles probably aren't the best, either.

I'm thinking of doing a compulsive factory-original restoration, using the original stapled wool felt gasket material around the baffles. Would that seal any better or worse that the modern neoprene gaskets?

[Winston L.]

Re: Oil Cooler

I have to agree with barstormer. I have seen a lot of baffeling that is worn badly in old airplanes. I have improved cooling by repairing, replacing or just sealing the baffles with a good high temp sealant. Winston

[Acroeric]

Re: Oil Cooler

Most any C-85 powered BC12-D will run considerably warmer than the A65. My clipwing with the 0-200 ran at 220 on 90 degree days and both my BC12-D-85's run at 210+ on 90 degree days. The one I currently own has very tight baffles and has all the inter cylinder baffles in place. It also has the scoop that directs air below the engine and to the oil tank and it still runs at 210. The other day I was climbing to 4k and I was very heavy. I had to stop at 3k to let her cool off before going up. The density altitude where I took off was 3k (350 MSL).

In my shade tree engineer opinion I think the Tcraft needs a less restrictive air exit. I opened up the lower cowling a bit on my clipwing and it dropped considerably. (20 degrees)

[Dusty]

Re: Oil Cooler

I seem to remember reading somewhere that STP is bad ju-ju for aircraft engines - something about zinc in the STP eating bearings or somesuch. Can anyone confirm?

Great idea with the aluminum foil.

Probably not relevant here, but a former mechanic mussed up the valve clearance on my Lyc O-235, making it run way hot.

[fearofpavement]

Re: Oil Cooler

Operating in the temperatures you mentioned (100 plus) I don't think you have any issues with oil temperature. Those kind of indications would sound pretty normal to me. If it isn't going over red line I wouldn't worry about it.

A better worry may be to figure out how to afford oil at the next oil change. I just picked up three cases of W100 at our local distributor at it is definitely going in the same direction as gas prices...