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Low oil temperature on cold mornings


John Womer

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I am having an issue with my 2010 Jabiru J230-SP.

 

The weather early this morning was typical for this time of year in New England... sky clear, temperature 0.0°C , dewpoint -4.0°C, and a light wind. My guess is that it was about 7°C inside my hangar, and I leave a Tanis heater on all the time.

 

My oil temp when I started up was 29.4 °C . Ten minutes of idling at 1200 RMP got it up to 32.2°. Taxiing five minutes to the end of the runway got it up to 40°C. And 1800 RPM mag checks and idling at 1400 RPM during run up got it up to 45.6 °C.

 

My POH lists the minimum oil temperature for take-off and flight at 48.9°C. I usually get there by the time I am 1000 feet AGL, but when I throttled back at pattern altitude while doing touch and goes, and then on approach after practicing ground reference maneuvers away from the airport, the oil temp quickly dropped back between 44°C and 46°C.

 

I am not particularly concerned about being a few degrees low. I am using AeroShell 20W-50 and I have no doubt it is flowing. The problem is over the next four months there will be many times when I want to fly and the ambient temperature will be in the -17°C to -7°C.

 

The Diamond DA-40 that I took lessons in last winter had metal inserts that partially blocked the cowl ducts behind the prop... but the cowl ducts on my J230 are already half "blocked" from the factory.

 

Any thoughts and suggestions would be much appreciated.

 

Thanks!

 

 

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I have taped off about 1/3 of my oil cooler in my J160, this manages to keep the temp around the 80c mark in the winter, but we are no where as cold as your temps here in Bundaberg.

 

I would try taping at least 60%.

 

Another pilot has fitted a roller blind in front of his oil cooler the works well and can adjust it in the air as the temps requires.

 

Adrian

 

 

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Trial and error blocking off the oil cooler

 

50% blocked would be a good start

 

I use heavy cardboard, upgrading to rubber sheet once size is determined

 

I did see a nice one covering whole cooler but with large holes evenly spread

 

Using these did play with my CHT altering airflow into cowl

 

 

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I am having an issue with my 2010 Jabiru J230-SP.The weather early this morning was typical for this time of year in New England... sky clear, temperature 0.0°C , dewpoint -4.0°C, and a light wind. My guess is that it was about 7°C inside my hangar, and I leave a Tanis heater on all the time.

 

My oil temp when I started up was 29.4 °C . Ten minutes of idling at 1200 RMP got it up to 32.2°. Taxiing five minutes to the end of the runway got it up to 40°C. And 1800 RPM mag checks and idling at 1400 RPM during run up got it up to 45.6 °C.

 

My POH lists the minimum oil temperature for take-off and flight at 48.9°C. I usually get there by the time I am 1000 feet AGL, but when I throttled back at pattern altitude while doing touch and goes, and then on approach after practicing ground reference maneuvers away from the airport, the oil temp quickly dropped back between 44°C and 46°C.

 

I am not particularly concerned about being a few degrees low. I am using AeroShell 20W-50 and I have no doubt it is flowing. The problem is over the next four months there will be many times when I want to fly and the ambient temperature will be in the -17°C to -7°C.

 

The Diamond DA-40 that I took lessons in last winter had metal inserts that partially blocked the cowl ducts behind the prop... but the cowl ducts on my J230 are already half "blocked" from the factory.

 

Any thoughts and suggestions would be much appreciated.

 

Thanks!

The cowl ducts are not 'half blocked off' - the idea is to direct air to the upper side of the cylinders and around them from above. This wont have much affect on oil temperature. You will need to block the air flow to the oil cooler - usually situated on the font face of the sump with its own air duct.

 

 

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I am having an issue with my 2010 Jabiru J230-SP.The weather early this morning was typical for this time of year in New England... sky clear, temperature 0.0°C , dewpoint -4.0°C, and a light wind. My guess is that it was about 7°C inside my hangar, and I leave a Tanis heater on all the time.

 

My oil temp when I started up was 29.4 °C . Ten minutes of idling at 1200 RMP got it up to 32.2°. Taxiing five minutes to the end of the runway got it up to 40°C. And 1800 RPM mag checks and idling at 1400 RPM during run up got it up to 45.6 °C.

 

My POH lists the minimum oil temperature for take-off and flight at 48.9°C. I usually get there by the time I am 1000 feet AGL, but when I throttled back at pattern altitude while doing touch and goes, and then on approach after practicing ground reference maneuvers away from the airport, the oil temp quickly dropped back between 44°C and 46°C.

 

I am not particularly concerned about being a few degrees low. I am using AeroShell 20W-50 and I have no doubt it is flowing. The problem is over the next four months there will be many times when I want to fly and the ambient temperature will be in the -17°C to -7°C.

 

The Diamond DA-40 that I took lessons in last winter had metal inserts that partially blocked the cowl ducts behind the prop... but the cowl ducts on my J230 are already half "blocked" from the factory.

 

Any thoughts and suggestions would be much appreciated.

 

Thanks!

I am having an issue with my 2010 Jabiru J230-SP.The weather early this morning was typical for this time of year in New England... sky clear, temperature 0.0°C , dewpoint -4.0°C, and a light wind. My guess is that it was about 7°C inside my hangar, and I leave a Tanis heater on all the time.

 

My oil temp when I started up was 29.4 °C . Ten minutes of idling at 1200 RMP got it up to 32.2°. Taxiing five minutes to the end of the runway got it up to 40°C. And 1800 RPM mag checks and idling at 1400 RPM during run up got it up to 45.6 °C.

 

My POH lists the minimum oil temperature for take-off and flight at 48.9°C. I usually get there by the time I am 1000 feet AGL, but when I throttled back at pattern altitude while doing touch and goes, and then on approach after practicing ground reference maneuvers away from the airport, the oil temp quickly dropped back between 44°C and 46°C.

 

I am not particularly concerned about being a few degrees low. I am using AeroShell 20W-50 and I have no doubt it is flowing. The problem is over the next four months there will be many times when I want to fly and the ambient temperature will be in the -17°C to -7°C.

 

The Diamond DA-40 that I took lessons in last winter had metal inserts that partially blocked the cowl ducts behind the prop... but the cowl ducts on my J230 are already half "blocked" from the factory.

 

Any thoughts and suggestions would be much appreciated.

 

Thanks!

Maybe keep the oil level barely on the stick. Less oil will help. What about ditching the oil cooler for the winter months and simply replace it with a length of hose inside fire sleeve for insulation. OR.... Plumb in an oil cooler bypass valve.

 

 

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Guest Andys@coffs
Why use Avaition. Oil oil is oil do a bit of research fined what ya need that could be suitable , that what I do

Hmm think if I was to make that statement (and I dont for one moment believe I would) then I might put a few disclaimers:-

 

1) be prepared to pay for any maintenance needed rather than expecting warranty to cover this, after all you consciously just chose to become a test pilot!

 

2) If you are prepared to throw away the manufacturers recommendation and look for alternate oil please make sure its for air cooled engines, I recall a poster here in the lubrication industry who said that normal car engine oil ( being for normal pressurised fluid cooled engines) will be next to useless in an air cooled engine. You may well have meant that anyway, with some luck who ever reads it and thinks "what a great idea" will also know it....

 

3) before actually doing anything consider ringing and discussing with the manufacturer. As others have said they are Bundaberg based where zero celcius is probably only possible inside a fridge... but having sold their products around the world there is a fair chance that your problems arent the first time they will have come across them.

 

I personally still only uses the oil that Jabiru tell me to...but I'm just a sook who would like to be able to call on my insurance if something occurs rather than explain why I chose to do my own thing in direct contravention of Jabiru's directions which arent exactly written in a way that suggests a bit of a play around the edges is expected and allowed...

 

Andy

 

 

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Thanks for your feedback, guys. I really appreciate it.

 

I think I'll start by covering part of the oil cooler with a small sheet of aluminum. Coincidentally, I ran into the guy who rents the hangar next to mine yesterday morning. He's got an RV-12 with a Rotax engine and, in the winter, he covers about 40% of his oil cooler with a piece of sheet metal secured by two of the bolts that hold his oil cooler in place.

 

I definitely need to get on this... It was cold again yesterday and even when climbing from 5,000 ft. to 10,000 ft. at a steady 300 ft. per minute, my oil temp didn't get over 61 °C.

 

What is an ideal oil temp with a Jabiru 3300?

 

 

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Thanks for your feedback, guys. I really appreciate it.I think I'll start by covering part of the oil cooler with a small sheet of aluminum. Coincidentally, I ran into the guy who rents the hangar next to mine yesterday morning. He's got an RV-12 with a Rotax engine and, in the winter, he covers about 40% of his oil cooler with a piece of sheet metal secured by two of the bolts that hold his oil cooler in place.

 

I definitely need to get on this... It was cold again yesterday and even when climbing from 5,000 ft. to 10,000 ft. at a steady 300 ft. per minute, my oil temp didn't get over 61 °C.

 

What is an ideal oil temp with a Jabiru 3300?

I would calibrate the gauge first!

 

 

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Desired oil temp is around 85 degrees Centigrade/celcius. IFyou run below these temps the oil will look milky because of moisture in suspension. very bad for your engine as more sludge and corrosion, quite quickly in some situations. Nev

 

 

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In the UK there is an approved thermostatic oil cooler adapter for Jabirus. Works very well and improved oil flow and pressure to the galleries. Made by Steve Rance. Details can be found by Googling SM13017 LAA Oil. That should take you straight to the LAA modification document for the device. With this installed there is no need for any duct tape etc.

 

Peter

 

 

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There is a bit of history about using non-aviation oil in Jabirus. In the early years, they actually specified an ordinary oil ( SG grade or better I think it was ). Then they withdrew this and specified an oil specifically for air-cooled aircraft engines. I think that maybe they learned something the hard way.

 

The temperatures in air-cooled engines are more variable and in particular the maximum temperature would be higher than for a water-cooled car engine.

 

With regard to the oil temperature, I have had about 80% of the inlet air to the oil cooler blocked off for years now and it has worked ok but these thermostat add-ons look like a good idea. But one advantage of restricting the airflow into the cooler is that the lower-cowl pressure will be reduced and therefore the airflow in the head-cooling ducts will be increased. There is no reason why you couldn't do both the restriction and the thermostat.

 

..... Bruce

 

 

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I was informed resently that my name was mentioned regarding oil temps. Yes I do manufacture the Thermostatic oil control adaptor (TOCA). I suffered the same cold oil problems with my Jabiru during the cold season and removing and replacing the cooler every season was a pain.

 

The problems are compounded if you have a cooler fitted with the original Jabiru doughnut. When the air is cold then blasting colder air over the cooler and sump will chill the oil almost as fast as it heats. The commerially available TOCAs or thermo sandwich plates as they are known work as well but are much bulkier due to being cast and usually come with 1/2" BSP thread. I designed my original one to fit my 2200 cnc machined from solid without the need to use a shorter oil filter, during the development phase it was determined that using AN8 hoses the oil would flow without any persevable pressure loss due to reduced drag, also my TOCA has bigger galleries, when the oil is less than 80C the the cooler is bypassed anyway.

 

It has been proved that on start up on a cold day, when the original Jabiru adaptor that has the brass fittings with 1/8"NPT ports the oil is sluggish to flow through the cooler as it has no choice, there is a significant oil pressure drop that can only be measured if the pressure sender if fitted to the Gallery (lower) port. There is the possibility that with cold oil and restrictions in the cooler circuit the pressure could rise enough to open the bypass valve sending some of the oil directly back to the sump, when my TOCA is fitted this is no longer an issue as the cooler is bypassed until the oil has warmed to 80C+.

 

A significant amount of cooling is done by the sump casting, even with the TOCA fitted in cold weather the oil can still remain cool unless the sump is partrially screened, this will have to be determined by experimantation. I have 2 settings on my sump inlet that I have to adjust according to seasonable OAT. My theory is that you could almost screen of the sump completely and with a large enough oil cooler let the TOCA do all the work.

 

There is more info in the link below or if you need more detail then use my email address

 

http://www.lightaircraftassociation.co.uk/engineering/Standard%20Mods/jabiru_engine.html

 

Steve

 

[email protected]

 

 

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  • 2 months later...

Sorry for the delay in replying. Many thanks for your suggestions. At present, fully blocking off the face of my oil cooler gets my oil temp up to 67c with an OAT of -18c, and on approach it staying just above the 49c minimum -- so no more flashing red lights. Not ideal, but certainly better.

 

 

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Holy thread necromancy Batman. I was going to search out this thread this week.

 

Yesterday I finished fitting one of Steve Rance's TOCA units and taking it for a fly (after some ground runs obviously, and finally getting rego renewal) after finding out about it from this thread. This unit rocks and Steve is great to deal with.

 

As advertised, the oil now gets to 80c and stays there. In all but hot summer days, I couldn't reach 70 before.

 

More tests to do, but this is a professional unit worthy of your consideration. It's 5mm wider than the standard donut, so I had the choice of cutting off a fin or two, or using a smaller filter. I went with a smaller filter (Z443) coz it seemed more elegant and I change every 25 hours anyway.

 

Very professional, BMAA approved unit.

 

Thanks for the thread.

 

For you northern neighbours (sorry neighbors), I often startup in -5 to -7C (23 to 19F), so comparable?

 

See - this site can be useful.

 

 

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This oil cooler thread has been very interesting. Many issues with cooling appear to be according to setup and how the aircraft performs in weather temp extremes.

 

Yes I agree that masking over the cooler does work if you have a standard setup but remember that the oil has no choice but to flow through the cooler when fitted with the Jabiru OCA (doughnut). In cold weather the oil flow may be partially restricted due to the viscosity and will struggle to get to the ideal temp range of 85C-95C, If oil pressure is high due to slower flow then it is very possible the relief valve can open dumping oil back to the sump and bypassing the bearings. Oil viscosity is clearly demonstrated in my engine by the dropping oil pressure as it approaches 90C+. Oil pressure is only genereated by the resistance of the oil as it flows to the parts in the engine, bit like putting your thumb over a hose pipe, thumb off = no pressure but full flow, thumb on = high pressure but lower flow, a lot of concern is raised about low pressures but as long as the flow is there then perhaps it is not as bad as thought, the down side with low pressure is it may not flow to the furthest away parts in the engine.

 

With a TOCA fitted the cooler is bypassed until the oil gets to a working temp, this results in a faster warm up time. In cold weather unless the oil reaches at least 85C+ then the TOCA sensor valve will remain closed and no oil will be diverted to the cooler.

 

The actual true oil pressure going to the important parts of the engine can only be measured when the pressure sensor is fitted to the 'gallery port'.

 

With the sensor fitted to the standard port a possible worse case senario is to have a completely blocked cooler circuit (kinked oil hose), a normal pressure reading on the gauge will be seen and no pressure in the 'gallery' leading to dire results. This is why I advise if doing work on the oil system to consider moving the sensor to the gallery or adding a second gauge for comparison. I did this during the testing phase and was surprised at the difference between the two ports, another reason I recommend AN8 hoses.

 

I am having another batch of TOCAs made and should be ready in a few weeks, I plan to be at Sun & Fun in April if all goes well and intend bring a few TOCAs with me just in case anybody going want to see/purchase with price saving.

 

For more info email [email protected]

 

Steve

 

 

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  • 5 years later...

I note someone said the TOCA is BMAA approved, can someone let me know the approval number as I have fitted one of Steves units (via Kev Hyam) and I need to submit a minor mod for the installation.

 

Ian Gardner

 

 

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Trial and error blocking off the oil cooler50% blocked would be a good startI use heavy cardboard, upgrading to rubber sheet once size is determined

 

I did see a nice one covering whole cooler but with large holes evenly spread

 

Using these did play with my CHT altering airflow into cowl

The best thing to use for blocking part of your oil cooler is the Teflon sheet you can buy in the hardware store as a cooking sheet for barbeques. This sheet is rated to 260 Deg C. If your oil ever gets to that temperature, you'll have more problems than a scorched sheet. Also, I have tested this stuff with a direct flame. While the blowtorch was on the sheet it would burn, but if you take the flame away from the sheet, the burning stops. I'm not sure how the sheet would go if it was set on fire and subjected to high speed air flow though.
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I have wondered about a flap-door for the oil cooler. It would be in the lower cowl entry, and rotate about a center shaft, driven by a push-pull wire in a snake, or by a model plane servo.

 

The model plane servo would make it easier to remove the lower cowl, while the snake is simpler.

 

At this time, it doesn't seem that the problem is so bad it needs all this work so that is why nothing has been done.

 

 

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