Hot oil temps

[John H]

Hi All,

I also have the Odyssey in my RV-9 and initally the oil temps were way out of line. I have built some 12 Vans aircraft and never saw high oil temps. Upon further investigations I discovered that the oil temp probe was defective giving me temps some 40 Deg F higher than normal. The use of a IR Temperature device aimed at the cooler after a flight comfirmed my suspicions. A quick check is to remove the probe from the engine insert it in a container of boiling water and see what the Odyssey reads. Also be sure you have the proper setup information in the Oil temperature setup menu.

Good luck,

John Higgins
RV-9 N194JH

[Bryan Wood]

Mine were hot on the maiden flight and it turned out to be the ramps that go on the upper cowl were on an upper shelf in my garage. When installed the temps were normal.

[lbgjb]

My rv10---standard IO540 with standard cowling but put in oil cooler from (http://www.aviationtechproducts.com/...ne__parts.html)
and also have side louvers. Fly in Florida--in summer climbed to 17,000 feet, max oil temp of 200. during warm weather fly 75% power with temps of 180-185. During winter have installed a butterfly valve on scat tube (http://www.nonstopaviation.com/rv10-...r-p-14566.html) and maintain temps of 180's. oil cooler has greater cooling than vans and fits in same place. obviates need for 2nd cooler with weight, expense etc. works great. lbb

[ZU-RVZ]

65 deg F, 5000ft amsl.

[lbgjb]

don't remember what altitude temps were, but ground temp was 90's with high humidity. I can climb at any speed, low or cruise climb, and have no high oil temps. My only 'problem' was too cool in winter, and fixed that with the adjustable butterfly--which is cheap and easy to install.(rare in aviation to have good product that works well, is made well, and is cheap to boot!!) i suspect with "larger" single oil cooler you will solve problem, but if you add side louvers, you will not have temp problem even in desert (is it one or 2 ss's??) lbb

[Mike S]

Originally Posted by lbgjb

but if you add side louvers, you will not have temp problem lbb

Details, photos??

[Deems Davis]

I've got 4.5 hours on an 290 HP IO 540, w/ James Cowl and Plenum, 1st and 2nd flight showed oil temps peaking @ 232. OAT 75F 4500 ft, 24.5 sq. I already have the airflow 2006X installed. I removed the left side heat muff and scat tubes, cut the bottom of the lower cowl forward 1" yeilding aprox 4.5 sq in increase in lower cowl exit area, and cleaned up some other obstructions in the lower cowl. 3rd & 4th flight showed oil temps peaking @ 215, OAT 70F 3500 ft 25 sq. The oil temp issue has been reported by several -10 builders, I know of 2 that have plumbed a 2nd oil cooler and it seems to have done the trick. I know of one builder that took extensive differential manometer (pressure) readings at various points in the lower cowl. they all consistently indicated that the lower cowl pressures were too high thus impeeding the flow of air through the oil cooler (complicated by Van's obtuse mounting of the O/C). I have spoken with several who have installed louvers, and it appears to me that this has consistently shown good results. I have concluded (?) that for the james cowl/plenum there is not enough exit area in the lower cowl and that is impeeding exit air and increasing the pressure. Several builders in this situation are also reporting CHT issues.
Today I finished installing louvers to the bottom of my cowl.



I'll fly again on Monday and report any changes.

[ScottSchmidt]

This has been discussed many times in the past. I posted the exact same thread after a few flights. I would be careful jumping to two oil coolers right away.

My first thought is that 435 is pretty warm on your CHT's but may be normal when breaking in the engine. I rarely see over 405 now after doing some very detailed baffle sealing. You would think that a 1/4" hole would not do much harm but it does. Tim did a great write-up on this. Read his thoughts on this too (link below). I did not believe it would make a difference but I was shocked. I still have the stock Van's cooler and have never had an issue. My alarm is set to 215 and I will hit that once in a while on hot (95+ deg days) but my CHT will still be at 405. When I do hit 215 I just level out for a few minutes and then continue my climb.
I have heard great results with improved oil coolers as well.

Here are a few more threads on the same issue.

http://www.myrv10.com/N104CD/mainten...022/index.html

http://www.vansairforce.com/communit...light=oil+temp

http://www.vansairforce.com/communit...light=oil+temp

http://www.vansairforce.com/communit...light=oil+temp

http://www.vansairforce.com/communit...light=oil+temp

[Deems Davis]

Originally Posted by Deems Davis

I've got 4.5 hours on an 290 HP IO 540, w/ James Cowl and Plenum, 1st and 2nd flight showed oil temps peaking @ 232. OAT 75F 4500 ft, 24.5 sq. I already have the airflow 2006X installed. I removed the left side heat muff and scat tubes, cut the bottom of the lower cowl forward 1" yeilding aprox 4.5 sq in increase in lower cowl exit area, and cleaned up some other obstructions in the lower cowl. 3rd & 4th flight showed oil temps peaking @ 215, OAT 70F 3500 ft 25 sq. The oil temp issue has been reported by several -10 builders, I know of 2 that have plumbed a 2nd oil cooler and it seems to have done the trick. I know of one builder that took extensive differential manometer (pressure) readings at various points in the lower cowl. they all consistently indicated that the lower cowl pressures were too high thus impeeding the flow of air through the oil cooler (complicated by Van's obtuse mounting of the O/C). I have spoken with several who have installed louvers, and it appears to me that this has consistently shown good results. I have concluded (?) that for the james cowl/plenum there is not enough exit area in the lower cowl and that is impeeding exit air and increasing the pressure. Several builders in this situation are also reporting CHT issues.
Today I finished installing louvers to the bottom of my cowl.



I'll fly again on Monday and report any changes.

Well, thought I'd report on the results of installing the louvers. I flew again today for 1 1/2 hours MP 28-25 ", RPM 2500. Alt 3500-6500. and oil temps were pretty much the same 215-220,as were the CYL temps. It was about 5-6 deg C warmer at lower levels today. I haven't given up completely on the louvers, and am considering adding a partial set (8 louvers) per side just outboard of the two full sets. My theory is that the existing louvers are all in the 'tunnel' portion of the cowl, and may not be having much effect on the remainder (e.g. like where the oil cooler is located). I did install a baffle inside of the oil cooler wedge mount. I got it from Bill G @ Airflow, he says that their testing shows the most of the air entering the Van's oil cooler exits through the bottom portion of the cooler. This baffle splits the intake air and directs 1/2 of it to the upper 1/3 of the oil cooler. (sorry no pics today). I also did some major work sealing leaks in the plenum/baffles.

[lbgjb]

put the louvers on the side of the cowl--probably solve problem. lbb