For my 0-360 Mama temp. (lycoming manual) sez...
CHT
400 deg. or below .
500 deg. max .
150-400 for max service life at cont. operation .
RB
| Thorp Air Command - T18.net http://t18.net/thorpforum/ |
|
| Engine Too Cold http://t18.net/thorpforum/viewtopic.php?f=29&t=8232 |
Page 1 of 1 |
| Author: | Jim Mantyla [ Fri May 25, 2018 10:30 am ] |
| Post subject: | Engine Too Cold |
Guys, I am wondering if my engine is running too cold. Let me explain. When i bought the plane the CHT was about 360F at cruise with the outside temperature about 75F. I did some changes to the baffling and the CHT came down to about 320-325F with outside temps about 75F. This winter I sealed all the holes I could find and changed the baffle tape material to really seal everything up so all the incoming air has to go through the cooling fins. When I did my first flight this year with the outside temp about 40F the CHT was 260-265F. Last night I was out and the outside temp was 77 F and the CHT got as high as 302F in cruise and 320F on climb out. I believe my CHT is working because it indicates the correct ambient temp before I start up. Your thoughts on this would be appreciated. Maybe I need to poke some holes in the baffles so that they are not as efficient, or maybe cut down the air inlet area? I have a Ratray cowl. Regards, Jim |
|
| Author: | jrevens [ Fri May 25, 2018 12:27 pm ] |
| Post subject: | Re: Engine Too Cold |
I think your CHTs are great, Jim. IMHO, cooler is always better - within reason of course. It’s not directly like oil temperature, where you want to reach a temperature sufficient to remove water. |
|
| Author: | Rich Brazell [ Fri May 25, 2018 1:36 pm ] |
| Post subject: | Re: Engine Too Cold |
For my 0-360 Mama temp. (lycoming manual) sez... CHT 400 deg. or below . 500 deg. max . 150-400 for max service life at cont. operation . RB
|
|
| Author: | Jim Mantyla [ Fri May 25, 2018 1:39 pm ] |
| Post subject: | Re: Engine Too Cold |
I should have mentioned I have an IO-320 in my plane. Jim |
|
| Author: | jrevens [ Fri May 25, 2018 6:07 pm ] |
| Post subject: | Re: Engine Too Cold |
Jim Mantyla wrote: I should have mentioned I have an IO-320 in my plane. Jim Shouldn’t matter. |
|
| Author: | TonyNZ [ Fri May 25, 2018 6:18 pm ] |
| Post subject: | Re: Engine Too Cold |
Like John says, if cyl temps are mid range no problems. Just make sure oil temp is 80 C plus to keep moisture out. Tony S ZK-VMS |
|
| Author: | Unclerap [ Fri May 25, 2018 9:08 pm ] |
| Post subject: | Re: Engine Too Cold |
Single probe or 4? Peak EGT at cruise? Most 4 cyl lycs run best lean and in the 300-350 CHT range as previously stated. |
|
| Author: | Jeff J [ Sat May 26, 2018 8:21 am ] |
| Post subject: | Re: Engine Too Cold |
Your temps sound okay but there is quite a spread between 77 degrees and 325 degrees. It is posiible the probe could be good at low end and way off high. If you are serious about checking it then I suggest the probe be suspended in boiling water (212 degrees) or some other medium where you can measure the temp to check it. I ran into an oil temp probe on a PT6A a while back that was good at ambient but 20 degrees off at 212. If the error scale was constant then it could have been off by 40 at 325. |
|
| Author: | Doug S [ Sat May 26, 2018 9:09 am ] |
| Post subject: | Re: Engine Too Cold |
If the temps. are correct, you can add more performance (speed or economy) start shrinking outlets of cowl. I would think you could bring CHTs up into the 325 range with little worry & a few more knots (or MPG) |
|
| Page 1 of 1 | All times are UTC - 6 hours [ DST ] |
| Powered by phpBB® Forum Software © phpBB Group https://www.phpbb.com/ |
|