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CHT problem

Blache

I'm New Here
Currently having a strange CHT problem with my from cylinder number 2 on a. O-360 180 HP RV7A on take off all cylinders will climb but my hot cylinder will get well above 400F and in cruise will stay in the 190s I've recently been just burning more fuel instead of burning my cylinder, but was wondering if anyone had an idea on what we could do to maybe fix this issue. back cylinders will sit in the 380s at around 11 to 12 GPH. I have just ordered a Louver kit from vans to hopefully help with the issue. we have recently redone the baffling which helped a little bit for takeoff runs but we are thinking to do a plenum instead to help.
 
Blache

We need some info before being able to help.

-Engine time in this aircraft? Is this something new? Is the engine being broken in?
-CHT on all other cylinders?
-Power settings, airspeed, fuel burn, OAT, altitude, flight attitude? Need numbers.
-Carb or fuel injection? (Assuming Carb)
-Constant speed or fixed pitch?
-Mags or electronic ignition? Ignition timing?

Do not cut louvers yet. There is something else going on.
If you are burning 11-12 GPH on full throttle climbout you are too lean.

GM
 
If it's a recent issue I would recommend troubleshooting the following for a quick easy answer, assuming you have an EMS and free Savvy account:

Induction System Leaks
Via Savvy, check if the ground idle MAP has increased dramatically relative to earlier flights.
Via Savvy, check if the #2 EGT remains roughly the same during leaning

Faulty CHT Probe
Probes can fail hot. Try switching the probe connectors between #2 and #4 and see if the problem follows or remains put. (Just remember #2 on the screen is now #4 and visa versa)

Hope this helps.
 
So, you are saying that in cruise #2 is 390 and all others are 380? If so, that is a normal spread. Suggest cutting down the blocking plate in front of #2 a bit. 380 is higher than normal for cruise, so suggest you do some work on your baffling. Likely eliminating leak points will bring those numbers down.

Larry
 
Blache

We need some info before being able to help.

-Engine time in this aircraft? Is this something new? Is the engine being broken in?
-CHT on all other cylinders?
-Power settings, airspeed, fuel burn, OAT, altitude, flight attitude? Need numbers.
-Carb or fuel injection? (Assuming Carb)
-Constant speed or fixed pitch?
-Mags or electronic ignition? Ignition timing?

Do not cut louvers yet. There is something else going on.
If you are burning 11-12 GPH on full throttle climbout you are too lean.

GM
Aircraft and Engine has a little under 800hours it is a O-360 with 1 P mag one regular both are properly timed. CS prop that I bring back on takeoff. Takeoff GPH is a normal 18 I like to keep the nose down and climb out at around 120s 130 to keep the temps down. Baffling is new and helped a little but thinking about installing a plenum.
 
Baffling

I have red silicone sealer with the standard baffling kit and while I can push it to get CHTs over 400, it's really easy to keep them under.

If you are not using the Savvy system, I also recommend it. It's very easy to see things you might otherwise miss. The presentation format is very helpful. If you upgrade to the paid service, they will analyze your data and give you some hints.
 
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