winter ops

yesterday was probably the coldest day for my 1998 RV4, which was buildt in California. OAT was -15°C (5F) in FL85, and the oil temperature never exceeded 63°C (145F). Usually I am keeping that around 90°C (194F). during descent, even though I kept the revs up, cyl 2 cooled down to 85°C CHT (185F).

question: for the next flight, my idea is I just use some duct tape, maybe strenghtened with a small sheet of aluminium, for example on the lower half of both inlets, to reduce the amount of cool air coming in?

what do you guys think, how is your experience in winter flying, what do you do?

Blocking the Inlets Might Not be a Good Idea

I think most owners that fly in the Northern States or cold weather block off only the oil cooler. In my case, I mount a restrictor plate behind the cooler and cover about 2/3 of the front (this is all that I'm able to reach) with aluminum tape. My oil temperatures seldom get above 170F, even with this. If you block the inlets, you risk uneven cooling of only the cylinder heads, rather than the sump. The issue is the oil temperature, not the heads. At the same time, I must admit that I am no expert on engines.

Terry, CFI
RV9A N323TP

Standard procedure is just to block off flow to the oil cooler (to some extent - maybe not completely). As Terry said, don’t block off cooling flow to the engine itself. Popular certified airplanes have cold weather kits that just block flow to the oil cooler - and they use the same engines as we do.

I had the same problem for my first 25 or so hours this winter in the northeast. I couldn't get my oil temp above 150? (New IO-360M1B). I installed the Anti-splat oil cooler shutter with a simple push/pull cable to the cockpit. Works like a charm, small adjustments keep the temp right where I like it. Great mod/easy install.

Jpm757 said:

I had the same problem for my first 25 or so hours this winter in the northeast. I couldn't get my oil temp above 150? (New IO-360M1B). I installed the Anti-splat oil cooler shutter with a simple push/pull cable to the cockpit. Works like a charm, small adjustments keep the temp right where I like it. Great mod/easy install.

Click to expand...

Did you install the shutter on the front or rear of the oil cooler?

well I have a flap with cable as well in my aircraft, that flap is behind the oil cooler and I had it fully closed. Maybe I have to look if I can change something there....

I installed the Anti-splatt shutter between the rear #4 baffle and the oil cooler. Just loosened the long an3 bolts, slipped the shutter in between, match drilled holes in flange and bolted to existing nut plates (existing bolts had plenty of available grip). Minor trimming to flange required. Ran a 3/16" Vans Bowden cable through L/H firewall pass thru and attached to cockpit sidewall with angle bracket. Took about 2 hours, oil temp can be adjusted quite precisely. I am using Vans baffling and oil cooler as supplied in FWF kit. YIO-360-M1B.

that anti splat oil cooler shutter seems to be a quite easy mod, I just checked their website. I have to do my annual soon anyway, when I remove the cowling again I will check dimensions etc to place an order. thanks for all your replies!

Shutter and more

It's cold in Alaska...in order to get my oil heat to an acceptable range I have installed the shutter system on the front of the oil cooler and a aluminum plate on the back.