2200 oil temps

[zodiac3813]

Hi everyone,

 

does anyone know the "acceptable" max oil temp for a 2200 engine? Mine, on a 26 deg OAT day, is reaching just under 100 deg (no matter what airspeed in climb), dropping back quickly on descent. The following relevant details:

 

• narrow (7 cm), deep (5 cm) heavy duty oil cooler mounted under the sump which allows 45 degree angle, direct air flow, fed by a (sealed) opening under the prop,
   
   
  
• 4 cm "lip" added to bottom edge of cowl
   
   
  
• there are no substantial gaps around the cooler where air can escape
   
   
  
• I recently added 2 x backward-facing vents directly under the cooler to try to "draw" more air through.... didn't work! (now I have 2 x holes to repair!)
   
   
  

 

The whole point is, I guess, how hot is "too hot"? I previously had a Zodiac 601 with 1800 Subaru engine that routinely reached 110 deg, but I guess the Subie is made of sterner stuff....

 

Lastly, this LSA 55 has a "skinny", hard-to-describe-the-shape-of cowl that I have only seen once before on an SK model Jab.

 

I did try changing the cooler for the original (?) K&H cooler, but that was no better, as I suspect the air was hitting the webbing at almost a 90 degree angle.

 

Any ideas????

 

Cheers, Jim

 

 

[Guest Qwerty]

We haven't seen much of you at G'town lately.

 

Cheers, Qwerty

 

 

[Captain]

Jim,

 

100 C is high. See JRMobile's recent posts on his oil temp.

 

Suggest that you also go to the Jabiru website and download the 2200 engine manual for the oil temps and limits.

 

Hope this helps.

 

Regards Geoff

 

 

[zodiac3813]

I think you must be thinking Degrees F ? This is centigrade degrees, hence my concerns. If it was in faranheight (is that how it's spell it?) yes it would be low!

 

Cheers, Jim

 

 

[blueline]

From memory 100 is max' continuous temp (even though on the J160 and J230 the redline only starts at 115). Check that the oil level is not above about half full and that the oil catch bottle is empty. Both these seem to raise oil temp.

 

 

[zodiac3813]

Thanks for the responses, guys: today I removed the backward- facing air scoops from the cowl under the cooler (hadn't helped at all) and taped up the holes where they were. I also sealed off any remaining (tiny) gaps in the ducting through the cooler where air could go. Then climbed at around 80 kts to 3000 ft. CHT was perfect all the way, 140 - 150 deg C, but the oil temp SLOWLY climbed to (again) just a fraction under 100 deg. The odd thing is that it doesn't drop when I level out and cruise at 2800 rpm / 95 kts.... only drops when descending / throttled back. I did check the sender in boiling water 50 hrs ago and it was ok, Has anyone had a dud sender? Does it give odd readings, or stay on 0?

 

I'm starting to think I may need to (somehow?) get the bigger / roomier cowl and mount the cooler square-on in the airflow to get it to work!! What a pai.

 

Cheers, Jim

 

 

[sseeker]

Hi Zodiac3818,

 

Just taking a stab in the dark here (not 100% sure whether it applies to your aircraft) but according to my Jabiru aircraft service manual for the J160C the Oil Temperature Gauge is an electronic instrument. They list a few methods for troubleshooting; check 10amp instrument fuse and replace if necessary, check 15amp main circuit breaker and reset if necessary, remove instrument panel and check cable terminals for security, check wiring at sender for security, replace sender or replace gauge.

 

Now I'm not 100% sure whether that applies to you as it's a different aircraft you own.

 

I hope this helped.

 

Andrew.

 

EDIT:

 

I also retrieved this info for you off the J160 pilot operating handbook for the 2200 (may differ because of engine cowl formats)

 

Red line minimum limit: 15C

 

Green arc normal operating: 80-100C

 

Red arc maximum limit: 118C

 

Yellow arc precautionary limit: 100C-118C

 

& Sorry for bringing up an old thread.

 

 

[ianboag]

If you go to SuperCheap and buy an oil cooler (their smallest transmission one) and mount it anywhere that you can inside the cowl - in series with the one you have - it will fix the problem. Adding more cooler AREA is a simple solution to your problem.

 

 

[dazza 38]

If you go to SuperCheap and buy an oil cooler (their smallest transmission one) and mount it anywhere that you can inside the cowl - in series with the one you have - it will fix the problem. Adding more cooler AREA is a simple solution to your problem.

HI all, shouldnt jabiru, put in another oil cooler if needed?:big_grin:

 

 

[sseeker]

I don't think they will if it's a kit built Jab.

 

 

[Bruce Robbins]

Zodiac3813,

 

Cooling (Cylinder Heads and Oil) can be problematic with any air cooled engines. There is voluminous info available on the subject if you search online, but I suggest you speak to knowledgeable L2s or LAMEs before doing too much changing. You will often find that fixing one thing will unfix another. It can be a frustrating business.

 

Having said that, in my opinion 100 degrees C is too hot for continous operation with a jab motor. We like to keep our school aircraft down below 80-90. You'll also find the temp going over 100 once you get a bit warmer than the 26C OAT you've quoted.

 

We have found that sealing the gaps around the oil cooler is sometimes counter-productive, and you may get better results by directing some cool air flow over the sump as well.

 

You should not need to add extra oil coolers.

 

Cheers,

 

Bruce

 

 

[ianboag]

It's like this ... the rate of heat flow out of a cooler is

 

(thermal conductance) x (oil temp - air temp) x (cooler area)

 

(just like Ohm's Law in electricity)

 

Thermal conductance depends on the cooler geometry and the air velocity flowing through it. You can influence it by blowing more air through the cooler, but not by a lot if there is already a "reasonable" flow present ie doubling the air flow does not double the thermal conductance.

 

The oil temperature adjusts itself so that the appropriate amount of heat is transferred. If the oil temp is too high increasing the cooler area is a relatively simple way to sort it.

 

Jabiru have actually been round and round a bit on this one over time. The 2200 originally came out with the small SuperCheap transmission cooler. When I got my early J200 with a 3300 engine it had the same small cooler and it didn't really work. Relative to the 2200 engine there was 50% more engine power and therefore about 50% more heat to get rid of - thermal conductance was the same, area was the same so (oil temp - air temp) had to be 50% greater. And it was ..

 

Jabiru now supply 3300's with Aero Classics coolers that have HEAPs more area then the one I originally had. In fact the Aero Classics one that I finally fitted is over-spec'd for the job and I have half of it taped off.

 

So if you have an oil temp problem adding area is a relatively easy fix. Fitting a new and bigger cooler is a drag (how do I know that?) but adding a small one in series is not all that hard. In fact if you think about it, that's what you're doing when you aim air at the sump .....

 

 

[zodiac3813]

Thanks people for all your advice and info. I'd add an extra cooler tomorrow if there was room under the cowl.... unfortunately it's a strange kind of fluted design (I'll try to post a pic) with VERY LITTLE room around the engine. Guess I could modify it or see whether Jabiru sell the other, fuller-shaped ones still (they may have one kicking around)

 

Cheers Jim

 

 

 

[ianboag]

For what it's worth - my guess would be that the second cooler wouldn't need a lot of airflow through it. You could hang it just about anywhere.

 

 

[facthunter]

High temps. OIL.

 

That is fair enough too. The oil should reach 85 though, as cooler than that and you are likely to get some moisture in the oil, which will show as cloudiness. If your temps rise increase your airspeed (if climbing). or reduce power (revs) if cruising. If you occasionally hit 100, I wouldn't panic, but I wouldn't want to see it sitting above 100 constantly. Nev

 

 

[ianboag]

I got all hot and bothered about the oil temp thing when my J200 had the original small cooler. Sustained effort on a hot day would get the temp up to 110 deg C (just below the redline). This seemed a bit disturbing as it felt a bit on the hot side (although not over the redline). I asked around about what was a "reasonable" value for the oil temp and got a confusing range of opinions. There didn't seem to be a lot of science or hard data behind most of it. 80-85 was widely deemed to be "good".

 

My first fix was to get a second cooler and sandwich it on the front of the one that was already there. It worked fine until the older cooler sprung a leak. I think the leak was related to it having been on and off too many times. Anyway I got all carried away after that and fitted (at no small expense) an Aero Classics cooler. Jabiru now use this and the Positech equivalent as the standard fit on 3300's.

 

Pioneer 300's with the Jab 3300 have the tiny oil cooler. I asked the NZ Pioneer dealer what he thought - he told me about flying round all over the place in Oz with the cruise oil temp between 100-110. Nothing broke.

 

I guess anything below the redline is OK or Jabiru would have put the redline lower. It's a reasonable guess that the redline is probably conservative enough that a few minutes at 10 degrees over won't break anything ...

 

Here's something else I found on a site dealing with Lycomings ...

 

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

For maximum service life, maintain the following recommended limits for continuous cruise operation:

 

(a) Engine Power Setting - 65% of rated or less.

 

(b) Cylinder head temperatures - 400°F. or below.

 

© Oil temperature - 165°F. - 220°F.

 

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

165 F is about 75 C, 220 F is just under 105 C.

 

Go figure.

 

IB

 

 

[Vev]

Completely agree with Nev’s assertions re oil temp .. if too low (< 80 deg c) you run the risk of not flashing off free water and causing corrosion problems.. alternatively temp spikes up to 100 deg c in the sump is not going to harm things either.

 

 

Base oils normally won’t begin to thermally crack until temps > 160 – 180 deg c, however consistent elevated temps or short excursions into extreme temps will produce a greater likelihood of oxidation and eventual break down in the base oil and additive system. Once oxidation starts it’s like a cancer that will generate a molecular auto decomposition of the hydrocarbon chain … in simple terms the oil is cooked and engine damage is assured to follow!

 

 

Outside of thermal breakdown, maintaining lubes within the right temp range also assists in the lubricant performance in terms of viscosity and hydrodynamic lubrication as well as the additive system to support anti-wear and dispersants.

 

 

The moral of the story … it’s a bit like the Three Bears … not too hot, not too cold but just right.

 

 

Cheers

 

Jack

 

 

[Modest Pilot]

First check the sender in boiling water. (100C) The engine people at Jabiru try for 80-90C in cruise. Remember the temp at the sender could be cooler than the oil temp in the centre of the engine. My J230 was on the hot side, so I bent up an aluminum shield to cover the sloping front fins and kicked it around the sump bottom 30mm. The sixes and early fours have cooling fins with four 1/4" treaded holes on the outside fins that can be use to attach but high temp sealant might work on the new sumps? I used a 32mm heater flange from Jab riveted on the shield with half a CV joint cover tied on to press up on a 32mm hole in the cowl. So far four other J230 at Gympie use this setup, drops the temp about 10C. Coming back home yesterday 36C oil temp at 92C OAT. I use duct tape over the hole when I go South in winter.

 

 

[wizzard1964]

Hi everyone,

does anyone know the "acceptable" max oil temp for a 2200 engine? Mine, on a 26 deg OAT day, is reaching just under 100 deg (no matter what airspeed in climb), dropping back quickly on descent. <CUT>

 

Cheers, Jim

Hey Jim,

 

I have an SK2200, I have just put later model heads on the 2200 motor, made new air ducts, opened up the top cowl by over 50% ...

 

A good friend of mine has a 6 cyl Jab, basically did the same thing, it runs much cooler.

 

One of our other club members is in the process of a 6cyl Jab motor rebuild, most likley due to running hotter than neccessary for years, hes opened up his cowl now..

 

Had a problem with one head during testing/run in, (it picked up a valve seat) but the guys at Jabiru could not get the bits to me quick enough (no charge)

 

Here are some links to photos of my progress on twitter, if interested

 

 

http://twitpic.com/yr2gw/full

 

 

http://twitpic.com/yr2nc/full

 

 

http://twitpic.com/yrhgk/full

 

 

http://twitpic.com/yw3ef/full

 

 

http://twitpic.com/ywdfo/full

 

 

http://twitpic.com/zthbk/full

 

 

Warick . . .

 

 

[zodiac3813]

Hi Warick,

 

thanks for that info and photos, unfortunately I can't do any major modifications as my Jab is 55- registered, factory built. Having said that, there's not much value in that if the engine cooks! I'm curious as to the location of your oil cooler? At the end of the red hoses obviously, but where do they go? Have you a photo of your oil cooler setup?

 

Cheers, Jim

 

 

[BigPete]

I've just re-read all posts and it occurs to me that no-one has asked what weight oil you are using. I'm pretty sure Jabiru are recommending 15W/50 for all year now. This may or may not make a difference. Check the website.

 

regards

 

 

[zodiac3813]

Using Aeroshell 15W50 all the time Pete. I spoke to Don at Jabiru yesterday and he said a temp range of 70 - 90 deg is fine, and not below 60 in winter. It can nudge 100 in the climb, or go over 100 for short periods; when I told him it had never gone over 100, he more or less said I was fretting unnecessarily.

 

One point he made was that on his Jab, he sealed a 5mm gap around the air intake shrouding and got a 10 deg drop in oil temp! Moral: ALL available air must go through the cooler................

 

Cheers, Jim.