Have a C-180 with right exhaust.

Right Cyl's temp's about 20 deg. hotter than left, all well within limits.

Wondering if the better cooling effect of the Maple Leaf exhaust fairing will impact more on the side it is put on to help even them out a bit.

I have installed the maple leaf fairing on a couple of airplanes, it helps but I wouldn’t call it a magic fix. Some time spent working the baffling/checking for induction leak/etc will probably help more. That said it looks sweet and for certain does not hurt. Easy install.

Thanks,

Any before and aft pics of the engine monitor?

Perfecting your baffling (or as close as you can get) is the best thing you can do for your engine. Get in there in a dark room with a partner and a flashlight, and look for "leaks". Then fix them. There are so many little things that can happen during maintenance and normal ops.....

MTV

Have done the light test but will do it again.

---

Right side cylinders have,

- Oil cooler in front of them.
- Are some 2" further back from those on the left.
- Have their shorter cooling side fins facing Fwd, Left ones their longer ones if I remember correctly.
- Eng. exhaust on that side.

Am I missing some more?

Fuel mixture distribution may also play a roll in the interesting equation.

You got it, larger fins are on the exhaust side…the intake valve doesn’t produce a whole lot of heat. Fuel distribution in the 470, or almost all carb’d engines (and some injected ones too) is not very good. The tube and riser design of the continentals has lots of connections that (in my experience) can start leaking. If you pop your balance tube off and look down inside each side and notice a different color one side vs the other, you’ve got a leak. If it’s drawing air upstream of #1 then all cylinders on that side will be lean.

That said, fluids do funny things. Could be baffles, intake leak, etc, etc. You’ll find it with patience. I bet you have, but checking the thermocouples are in the cylinders you think they are (heat #1 and verify #1 on your instrument increases). I’ve seen more than one with a wire or two crossed. It happens.

Good luck.

Oh almost forgot, the inter-cylinder baffles need to be tight and true. A small gap will make a huge difference.

Thanks S.pat,

Good points. We did take the balance tube out, color inside the intake manifold looked very similar. Did notice that the balance tube "cups" that fit to the manifold ends looked both black but the texture was very even on one side and to some extend granular on the other.

Risers at the intake manifold do not align very well looking front to back inside of it. . Wonder if the edges that protrude maybe 3-4 mm could cause the flow to be somehow disturbed.and have a negative effect on fuel air mixture feeding, but then, I did not see noticeable difference between both manifolds.
Do they have some play were they attach to the cylinder before tightening to try and align them better??
Remember reading that Steve Knop suggested to check on that if memory serves well. Any feedback on this?

We have done 3 intake manifold leak tests taking off the carburetor, adapting a flange to connect air pressure. No leaks were found.
Inflight leak test did give clues of having one but I don't know how accurate that is.

"Gami Spread" inflight test, about 2 gls which is not unusual for an O-470. Lean range, worst Cyl. 175 deg.

Going back to the title Q. I called Maple Leaf, they said that their exhaust fairing did indeed lower a little more Cyl temps on the side it is installed. May consider putting one on after doing again the baffle light test and then stop nit picking...

I posted reference the Maple Leaf fairing on or around April 6, 2021. Lowered my temps 10-15 degrees. My 2-4-6 cylinders ran hotter and the temps on those dropped. So not uniform on all Cylinders. Acorn Exhaust. O470U. Updated Image. -Bruce

Thx for the good pic Limerick. What a nice aircraft and pickup.

You mentioned that your 2-4-6 Cyl's Temp went down. Do you recall if 1-3-5 went down pretty much the same amount or if there was a different Temp drop depending on which side?

My 2-4-6/left ones are fine.. 1-3-5/right ones are about 25 hotter but still within conservative limits so I would consider putting the exhaust fairing only if it would help lowering these last ones more.

The fairing looks very nice.

I really can not remember much about the right side as it ran cool, it was a long time ago and my notes are long gone. If you found my 2021 post, I mentioned I did not want to install the shark fins and after much research I ended up with the fairing. My left side was/is always hotter (18 years now same engine 2350 Hours). It's the metal cylinder baffles that are worn and leaking to some degree. I just needed the left to run cooler without hitting 400 so often( Southern CA and Arizona temps) and at that time did not really understand how important the baffling is.

My hottest Cylinder #4 runs 370-380. My coldest Cylinder #5 behind the oil cooler runs around 300 and is original with 78/80 last compression test, bore scope shows scoring, dry plugs but have not pulled it yet. Unbelievable for sure! I really don't care what the temp spread between the cylinders is. Not sure this helps.

Thx for the good Info.

Cyl 5 deserves a trophy.being original and having those hours and compressions.

What engine are you running?

My temps are between 310 on Cyl.6 and 360 on Cyl..1 but usually with only 30 spread. O-470,,,