conom06d Posted July 9, 2010 Report Posted July 9, 2010 I have a 1961 M20B with a motor which has 2077 hours on it. I am currently in Prescott, AZ which is at 5000 feet elevation and is normally 90-95 degrees, which probably puts DA around 6500' on average. My issue is... last 4-5 hours, plane has been running rough slightly and feels more like it is straining to takeoff and climb. I know this is probably due to the DA mentioned above and the heat. My concern is that my oil temp gauge has been reading high in the green arc close to the red line on the old style gauge. I think this is probably cuz of the heat lately. My other concern is that the oil pressure is usually in the high green arc to mid yellow arc depending on planes weight and OAT. Should I be worried at all about these indications in these such old gauges? I have a feeling I am being just a bit paranoid but would prefer some others inputs on their experience with the O-360 at high altitude and high OAT's. Once i get the plane leveled off it generally becomes more smooth but even at 9500' here its been around 20-30*C. Thanks in advance Jason
140pilot Posted July 17, 2010 Report Posted July 17, 2010 I cant speak for high altitudes but my 78 M20C had 2200 SMOH and I would usually see temps running 100 over OAT and in climb about 110 above OAT. So on a 95 degree days I was seeing around 200 and maybe 210 on climb. As for oil press I was seeing 45 psi on start and at oil temps around 200 I would see around 35 psi. When I was running rough it was usually a lead fouled plug.
M016576 Posted July 18, 2010 Report Posted July 18, 2010 I'm with 140pilot... In ridgecrest, summer on a 95-100 degree day, I see about 200 in the climb, 190 once I'm levelled off. Oil pressure is normally 65psi in flight, but idle on deck I normally see about 50psi. The only time I've ever felt her rough is on a single mag with a fouled plug (too rich when taxiing at a high DA).... it's easy to pick that up if you've got a JPI: the EGT will normally be about 75 degrees higher than the others on the fouled cylinder. -Job
conom06d Posted July 18, 2010 Author Report Posted July 18, 2010 ok thanks guys. Ill keep an eye out on those temps and press readings. I dont think i have any fouled plugs as that was the first thing i had them clean. I think i was just a worry wart as it was my first time with the plane at a high DA location. All seems well now though but i will get used to noticing my needle movements
rdv Posted July 19, 2010 Report Posted July 19, 2010 It was about 85 here yesterday when I went flying. I had about 200-205 in climb. Levelled of at 5000', maybe 65 OAT and it only cooled to about 190-185 ish. I think I have a temp issue. When I got the plane I was told the baffles were dried and stiff, and probably were not doing there job very well. When I had the cowls off the other day, they did feel a little stiff. The engine in this 67 F has about 1750 hrs. Will new baffles make a big difference? When it gets warm, should I leave cowl flaps partially or even fully open in cruise below 150mph IAS? What is the highest cylinder head temp I should see in cruise? I think I had about 370 on #3 (22, 2400). Ryan
scottfromiowa Posted July 19, 2010 Report Posted July 19, 2010 You should NOT have to leave cowl flaps open in cruise below 150. If you do baffles or other issues are likely present.
rdv Posted July 19, 2010 Report Posted July 19, 2010 Alright, what is excessive oil temp in cruise this time of year?
tablor Posted July 19, 2010 Report Posted July 19, 2010 I'd recommend watching these videos from Lycoming. It's not solid great info from beginning to end, but there's certainly some good stuff and a discussion of oil temps with some guidance and suggestions. http://www.lycoming.textron.com/support/training/videos.html I think good advice for any issue is knowing your airplane. All of our engines are going to behave slightly differently. I use the notes section in my logbook to record engine stuff from time to time in order to see that it hasn't changed. Don't know exactly which baffle you'd have as I don't see your year/model, but the older airplanes with the 'dog house' don't rely much on the rubber baffle material. If it were in bad shape I don't think it would make a harmful difference (perhaps not even appreciable). On the newer designs where the rubber material provides the seal between upper and lower cowling, look on the inside of the cowling to see where the rubber is rubbing and where it's not, that might give you some idea where you are and aren't getting a good seal.
scottfromiowa Posted July 19, 2010 Report Posted July 19, 2010 Anything in the green is acceptable...
conom06d Posted July 20, 2010 Author Report Posted July 20, 2010 Quote: scottfromiowa Anything in the green is acceptable...
scottfromiowa Posted July 20, 2010 Report Posted July 20, 2010 What would concern me is if this is a new trend...always was centered in middle of green, but now has moved to top of green arc...change in "normal" is my que that something, whether gauge, probe, wires, cowl flaps, oil cooler, oil lines, angle of climb, outside temps is significantly different and maybe NOT functioning properly. I have issues right now with my stock cylinder head temp probe as it is now reading in the 200 range when my GEM is 300-325 for all cylinders... My oil pressure and temps have remained consistent on my gauges (steady in th green) during climb and cruise since I purchased...my mechanic fought high oil temps with another E he works on. His had the oil cooler re-location and a spin on oil filter, but was otherwise stock with baffles in good condition. I can't recall if he had a cowl closure (lower guppy) installed. Anytime you are near peak on a gauge I would attempt to identify what is causing the issue. Please update when you sort it out...Good luck, Scott
conom06d Posted July 20, 2010 Author Report Posted July 20, 2010 Quote: scottfromiowa What would concern me is if this is a new trend...always was centered in middle of green, but now has moved to top of green arc...change in "normal" is my que that something, whether gauge, probe, wires, cowl flaps, oil cooler, oil lines, angle of climb, outside temps is significantly different and maybe NOT functioning properly. I have issues right now with my stock cylinder head temp probe as it is now reading in the 200 range when my GEM is 300-325 for all cylinders... My oil pressure and temps have remained consistent on my gauges (steady in th green) during climb and cruise since I purchased...my mechanic fought high oil temps with another E he works on. His had the oil cooler re-location and a spin on oil filter, but was otherwise stock with baffles in good condition. I can't recall if he had a cowl closure (lower guppy) installed. Anytime you are near peak on a gauge I would attempt to identify what is causing the issue. Please update when you sort it out...Good luck, Scott
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