VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 01-05-2017, 05:37 PM
gen1313 gen1313 is offline
 
Join Date: Sep 2014
Location: Forbes, NSW, Australia
Posts: 35
Default Oil Temp

I finally have my RV-14 in the air. Aside from the excitement of the moment and the realisation of just how well it flew from the start I was paying close attention to temps. CHT's are great, nothing over 195C (385F) on climb and it is fairly hot here at the moment 35C (95F).
Oil temp on the other hand is higher than I would like. Regularly seeing 90C (195F) and up to 110C (230F). Anyone having similar experiences or any ideas?
__________________
Graham Haley
RV-14 #140181
Flying 5th January 2017
70+hours now
Reply With Quote
  #2  
Old 01-06-2017, 01:24 AM
salto salto is offline
 
Join Date: Apr 2015
Location: Wee Waa Australia
Posts: 229
Default

Let me be the first to congratulate you Graham.
Big effort and commitment to get it finished so quickly. 👍
__________________
Kit 140241
Tail Feathers done
Fuselage kit completed.
wings almost complete.
Flaps and ailerons done.
Canopy next. Phew!
Reply With Quote
  #3  
Old 01-06-2017, 05:29 PM
Aussieflyer Aussieflyer is offline
 
Join Date: Jan 2015
Location: Redcliffe, Queensland, Australia
Posts: 44
Default Australian Temps

My first 50 hours were conducted in outside temp of low to mid 80 degrees (Florida climate). My oil temps were consistently around 195 degrees. On sustained climbs I got high temps of 205 once or twice. I was hoping with the change out of run in oil to normal 100Wplus would see a slight decrease. Not the case.
I read an oil related article last week in Vans Airforce (forget exactly where), the author was technician. It was quoted the correct oil temp for Lycoming's was between 185 to 215. I don't think you have got a worry, as the engine frees up it should run a bit cooler.
My CHT's max out at 345 degrees and cruise at 310.
Hope this helps
Alan
Reply With Quote
  #4  
Old 01-06-2017, 06:35 PM
RV10inOz's Avatar
RV10inOz RV10inOz is offline
 
Join Date: May 2008
Location: Brisbane Qld. Aust.
Posts: 2,047
Default

Quote:
Originally Posted by gen1313 View Post
I finally have my RV-14 in the air. Aside from the excitement of the moment and the realisation of just how well it flew from the start I was paying close attention to temps. CHT's are great, nothing over 195C (385F) on climb and it is fairly hot here at the moment 35C (95F).
Oil temp on the other hand is higher than I would like. Regularly seeing 90C (195F) and up to 110C (230F). Anyone having similar experiences or any ideas?
Graham,

You actually WANT your oil temp up there, especially given it will be lower in winter nd when the engine settles down.

Climb at around 120 knots IAS.

All the best.
__________________
______________________________

David Brown


The two best investments you can make, by any financial test, an EMS and APS!
Reply With Quote
  #5  
Old 01-06-2017, 06:35 PM
czechsix's Avatar
czechsix czechsix is offline
 
Join Date: Mar 2006
Location: Spring Hill, KS
Posts: 254
Default

Quote:
Originally Posted by gen1313 View Post
Oil temp on the other hand is higher than I would like. Regularly seeing 90C (195F) and up to 110C (230F).
Quote:
Originally Posted by Aussieflyer View Post
It was quoted the correct oil temp for Lycoming's was between 185 to 215. I don't think you have got a worry, as the engine frees up it should run a bit cooler.
I guess I'd be a bit worried seeing 230F on the oil temp. I had a friend with a Mustang II (O-360, Hartzell) that had a prop rpm runaway due to high oil temps...the oil got so thin that the governor couldn't keep the rpm under control and it went from 2400 rpm to over 3000 in just a couple seconds. Fortunately it all stayed together, but made for an exciting test flight.

Then there's the question of how good the lubrication is at 230 F...again, the oil is getting thinner and its lubricating qualities are going to be compromised at excessive temperatures, and at some point you could be seeing accelerated wear. I don't know what that point is, just saying that it's legitimate to be concerned about high oil temps.
__________________
Mark Navratil
Spring Hill, KS
RV-8A N2D #80583 - built/flew/sold
RV-14A #140017 - wings complete, empacone in progress...

Last edited by czechsix : 01-08-2017 at 01:21 PM. Reason: edited incorrect information about Lycoming's oil temp limit
Reply With Quote
  #6  
Old 01-06-2017, 07:13 PM
Kyle Boatright Kyle Boatright is offline
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 2,933
Default

Quote:
Originally Posted by czechsix View Post
I guess I'd be a bit worried seeing 230F on the oil temp. I had a friend with a Mustang II (O-360, Hartzell) that had a prop rpm runaway due to high oil temps...the oil got so thin that the governor couldn't keep the rpm under control and it went from 2400 rpm to over 3000 in just a couple seconds. Fortunately it all stayed together, but made for an exciting test flight.

Then there's the question of how good the lubrication is at 230 F...again, the oil is getting thinner and its lubricating qualities are going to be compromised at excessive temperatures, and at some point you could be seeing accelerated wear. I don't know what that point is, just saying that it's legitimate to be concerned when the oil temp is that much higher than Lycoming's recommended 215 F limit.
Lycoming's redline is 245, IIRC.
__________________
Kyle Boatright
Atlanta, GA
2001 RV-6 N46KB
Reply With Quote
  #7  
Old 01-07-2017, 02:06 AM
salto salto is offline
 
Join Date: Apr 2015
Location: Wee Waa Australia
Posts: 229
Default

Sounds like increased airflow or larger oil cooler for high ambient air temperature ops. 40deg+ Celsius is a common temperature for outback Australia. There is a slide restrictor for cooler months(cockpit adjustable)
__________________
Kit 140241
Tail Feathers done
Fuselage kit completed.
wings almost complete.
Flaps and ailerons done.
Canopy next. Phew!
Reply With Quote
  #8  
Old 01-07-2017, 07:56 AM
olyolson's Avatar
olyolson olyolson is offline
 
Join Date: Dec 2009
Location: St Louis, MO
Posts: 644
Default Oil temp

Graham,

I recently had my IO-360 overhauled and had oil temps in the 195-230 range during the break in with mineral oil. After the engine break I changed the filter and switched the oil to Phillips XC 20W50 with Camgaurd and the temps are now stable at 185-195 in the summer.

As other guys have said, probably just a combination of a tight engine and using break in oil. Keep an eye on the temps and re-evaluate after engine break in. Then if it's still high look at the oil cooler location, airflow, exit area etc.

Oly
__________________
RV-4, IFR
AEIO-360, Hartzell C/S
RV grin every flight
"Sure is nice to have smart friends"

Last edited by olyolson : 01-07-2017 at 01:10 PM.
Reply With Quote
  #9  
Old 01-07-2017, 09:27 AM
DanH's Avatar
DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 7,226
Default

Quote:
Originally Posted by gen1313 View Post
CHT's are great, nothing over 195C (385F) on climb and it is fairly hot here at the moment 35C (95F).
Oil temp on the other hand is higher than I would like. Regularly seeing 90C (195F) and up to 110C (230F). Anyone having similar experiences or any ideas?
A few notes.

Lycoming's IO-390 operating manual is clear: Oil Temperature: The maximum permissible oil temperature is 235F. For maximum engine life, desired oil temperature is 180F.

Something over 200F during a slow climb is to be expected. Look at the oil cooler performance charts, and note how airflow affects cooling capacity. Pressure drives the flow. At 120 knots, available pressure is only half of that available at 170 knots.

It's often stated that an oil temperature of 212 or higher is desirable "to boil the water out of the oil". Actually, water evaporates just fine at room temperature; temperature increase just speeds the process. At 180F, the vapor pressure of water is about 30 times the pressure at 59F.

Boiling merely demonstrates that vapor pressure has exceeded local pressure at some location in the liquid. Local pressure drops with altitude, so boiling temperature at sea level isn't relevant anyway. At typical RV cruise altitudes (8500~11500) the boiling point of water is in the low 190's...not that it matters.

Higher overall CHT and oil temperature during break-in is to be expected. However, I suspect some seal and baffle work is in order. It seems to be part of the Phase 1 process for most builders. Here the forward governor doesn't help.

My oil temp sender indicates about 7F warmer than actual. If you look up the specs, the tolerance for those senders is really wide. Give yours a reality check.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
Reply With Quote
  #10  
Old 01-07-2017, 11:09 AM
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 7,058
Default

Quote:
Originally Posted by DanH View Post
A few notes.

Lycoming's IO-390 operating manual is clear: Oil Temperature: The maximum permissible oil temperature is 235F. For maximum engine life, desired oil temperature is 180F.

Something over 200F during a slow climb is to be expected. Look at the oil cooler performance charts, and note how airflow affects cooling capacity. Pressure drives the flow. At 120 knots, available pressure is only half of that available at 170 knots.

It's often stated that an oil temperature of 212 or higher is desirable "to boil the water out of the oil". Actually, water evaporates just fine at room temperature; temperature increase just speeds the process. At 180F, the vapor pressure of water is about 30 times the pressure at 59F.

Boiling merely demonstrates that vapor pressure has exceeded local pressure at some location in the liquid. Local pressure drops with altitude, so boiling temperature at sea level isn't relevant anyway. At typical RV cruise altitudes (8500~11500) the boiling point of water is in the low 190's...not that it matters.

Higher overall CHT and oil temperature during break-in is to be expected. However, I suspect some seal and baffle work is in order. It seems to be part of the Phase 1 process for most builders. Here the forward governor doesn't help.

My oil temp sender indicates about 7F warmer than actual. If you look up the specs, the tolerance for those senders is really wide. Give yours a reality check.
All good advice.

And I will add....

Being concerned about oil temp. (as long as it is not getting close to a critical value) on a brand new unbroken in engine is pointless.

Wait until the engine has at least 50 hrs on it and then re-evaluate.
__________________
Any opinions expressed in this message are my own and not necessarily those of my employer.

Scott McDaniels
Hubbard, Oregon
RV-6A (aka "Junkyard Special ")
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 10:14 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.