Hot Running Engine

[reileyr]

Pokette, S/N 00028 ran very hot from the day I picked it up at Yakima. On my first test flight, oil temp increased past the old 220F red line after thirty minutes in the air (100F OAT). I reduced power and landed thinking there was a problem. None found. Flew the plane to Texas and continued to see 220 -230F on hot days or at altitude. Checked temperature prob for accuracy OK. Checked engine timing OK. About a year ago I added the larger air inlet plenum and 4-in-None exhaust and did not see any detectable difference in the oil temperature. I installed a temperature prob at the oil cooler air inlet and one at the center of the outlet. Air temp in 85F; air temp out 165F proving oil was flowing through the cooler. Oil temp gage stabilized at 215F during this test. I continue to live with 210-230F oil temps except during the winter months and pink cylinders at the exhaust ports. Much of my experience is documented with a string of emails back and forth to CC.

The ultimate solution may be to move back to Alaska where my Cub will find peace and harmony with the environment. The plane is really perfect for cold weather as I get 180F oil temps when there is snow on the ground. Richard

[Pokette]

Richard, thanks for your post. I knew I wasn't the only one.
Today we tried "duck" taping an extension on the lip and saw an oil temp drop of close to 20 degrees. I think we will be working on this instead of a new oil cooler. Need to draw air over the cooler for it to be effective. So delta p was not great enough for that. Still temp was up to 200 pretty quick, but not 220, Hopefully CharlieVictor will be breating easier soon.

[rkortge]

My plane runs hotter than I would like also. I would be interested in any feedback on cooling me down. Seems like it runs a little cool in the winter and a little hot in the summer. Something adjustable would be awesome.

Rich Kortge # 82

[Pokette]

Rich, I uploaded some pictures of the lip extension we tested. It gave a temp drop of 15 degrees. We are going to make a bolt on lip with a greater extension and better formed. The oil cooler is not effective without air going over it. Increasing delta p by increasing the lip extension draws more air through the cowling making the cooling more effective.

I have a simple plate that is attached at the skat entrance on the back baffeling that I attach in the winter.

I hope you can view the pictures, not sure how to include them here...

[couleeone]

Rich, I uploaded some pictures of the lip extension we tested. It gave a temp drop of 15 degrees. We are going to make a bolt on lip with a greater extension and better formed. The oil cooler is not effective without air going over it. Increasing delta p by increasing the lip extension draws more air through the cowling making the cooling more effective.

I have a simple plate that is attached at the skat entrance on the back baffeling that I attach in the winter.

I hope you can view the pictures, not sure how to include them here...

Sounds very interesting and simple, I like it, but the pictures didn't show up. How about a link to where else you may have them posted?

Geo

[couleeone]

For additional info, when I am running at manuevering speed or less training students the temp stays at 200 or less.

Geo

[foxstardoc]

I am one of the fortunate folks who have a cool running engine. On the previous forum, several people had high oil temps like you are describing. Mine was always lower so we calibrated the gauge and replaced it as well. I run no higher than 200 degrees even flying around here with OAT's in the mid 90's. I have SN 00049 which was the second S2 with 4 in none. There must be a difference in baffling causing so much difference in temps. I also continue to have good compressions at 180 hours, so the high oil temps may be related to the cylinder problems. So far I have been fortunate..
Ken

[Pokette]

Here is a link to the pictures:
http://www.supercub.org/photopost/sh...86&ppuser=5184

I received four new cylinders from TCM and did an immediate valve job on them, they have been running great for over 40 hours now!

Diana

[Pilawt]

There must be a difference in baffling causing so much difference in temps. I also continue to have good compressions at 180 hours, so the high oil temps may be related to the cylinder problems. So far I have been fortunate..

#62 (S2, 4-into-none) usually stayed around 180-200 in warm conditions, yet still needed all four cylinders reworked at 150 hours TT (all four leaking through the exhaust valves, #4 down to 40/80). Installation of the new, larger oil cooler plenum immediately reduced oil temp another ten degrees.

[couleeone]

I have great compression and my cyclinders are good. I am about to turn 600 hrs on the tach so I am out front in time