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Engine Cylinder Overheating
Any suggestions would be appreciated.
Thanks
David Begin
- David Begin
- Posts: 10
- Joined: Wed Jul 04, 2012 8:16 pm
Re: Engine Cylinder Overheating
I would start with baffles.
Andrew
61250
- Andrew Foster
- ICS member
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Re: Engine Cylinder Overheating
I don't know if the singles have an issue common to Twins. When the Twin's cowling has been removed and replaced, the forward baffles frequently are pushed so that air gets by them on the outside instead of getting pushed over the cylinders. It has happened so often in the past, our shop now tells us that they have checked and the baffles are positioned correctly.
Hopefully it could be something that simple. I'll be interested to hear if baffles are the answer.
Patricia Jayne (Pat) Keefer ICS 08899
PA-39 #10 Texas
N3322G- ICS member
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- Location: Fort Worth, Texas area
Re: Engine Cylinder Overheating
- David Begin
- Posts: 10
- Joined: Wed Jul 04, 2012 8:16 pm
Re: Engine Cylinder Overheating
Dirty air filter also crossed my mind - with the drought air filters can get dirtier faster.
Patricia Jayne (Pat) Keefer ICS 08899
PA-39 #10 Texas
N3322G- ICS member
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- Location: Fort Worth, Texas area
Re: Engine Cylinder Overheating
On my 250 the #5 cylinder is always the hottest; sometimes in the summer time it will reach 400 when climbing. What airspeed are you climbing? Being at 6500 MSL, definitely harder to climb than at sea level, but it does seem too high.
Mark
Mark Anderson- ICS member
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- Location: Huntsville , AL
Re: Engine Cylinder Overheating
Maybe a quick timing check my be a good idea as well
Andrew
- Andrew Foster
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Re: Engine Cylinder Overheating
Zach Grant L1011jock- Technical Advisor
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- Location: Indianapolis KEYE
Re: Engine Cylinder Overheating
Well guess what, during re-installing the cowling last spring, I had not gotten the nose pieces back on and had a piece of baffle in-op.
Can't stress that enough... when I had a single 260 #5 was always the hottest until I got the baffle frenzy and tightened them up.
Jim
- MULEFLY
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Re: Engine Cylinder Overheating
climb out,
25rpm/25map
115-120 mph/knots
From sea level - to cool my CHTs i can only climb at 500 fpm or so and I have to reduce power.
Thoughts?
PA-250
IO-540 A15A
Kris
- Kristofer Duckett
- ICS member
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Re: Engine Cylinder Overheating
Read my response above. Baffles baffles baffles!!!!! First, your red line is set wrong on your JPI if you are using it as a primary. You should be a 500 degree CHT redline. Next, if you have a carbureted engine DONT PULL THE THROTTLE BACK IN CLIMB. If your baffles are good, but OATs are high, you can see the numbers you posted in the pic, and what you have left is fuel to cool. Pulling the throttle back in climb actually leans the engine. There is absolutely nothing wrong with climbing at wide open throttle. Why pull the throttle back to 25" only to have to push it back in as you climb. Over square is an old wives tail. One has nothing to do with the other. You could just as easily read power in degrees per second and feet of water for example if that was what was used at the time (and then the numbers wouldn't even be close). You want to climb out of the heat as quickly as possible. Just a 10 degree difference in OAT makes a huge difference in cooling efficiency.
Zach
Zach Grant L1011jock- Technical Advisor
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Re: Engine Cylinder Overheating
Randy Johnson- Posts: 176
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- Location: Boston Area (BEV)
Re: Engine Cylinder Overheating
Baffles appear to be in very good shape.
I do appear to have a cowling that was designed for two exhausts but I only have one exhaust installed. Not sure if that has anything to do with #2 running hot.
On a descent I have the opposite problem, #2 cools much quicker and I get the shock cooling alert.
Mechanic bore scoped the cylinder and everything looked good.
Richard Lanning- Posts: 65
- Joined: Tue Apr 15, 2014 11:08 pm
- Location: South Florida
Re: Engine Cylinder Overheating
I will check baffles.
Vince
- Vince Hoffart
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