turboplanner Posted July 6 Posted July 6 7 hours ago, T510 said: How does an oil become "not suitable anymore" when it was suitable from 1989 when the 912 series was released. Refer to the small print. You as a user might think all those engines were identical. I was doing some research on the V6 Holden a while back and the one model has had multiple changes, some supplier, some material, some different machining etc. Mostly to improve the engine. It wouldn't surprise me at all if the latest iteration of the 912 has the same charts. In this process not every change gets the results that initial testing indicated. So the manufacturer issues Advice notice from a break point. 7 hours ago, T510 said: Obviously different 912 models and derivatives may require different oil grades but if you have been using brand "x" oil for 20 years with no issues it begs the question how it becomes no longer suitable and why is a change required. The oil company may have issued an update in the formula which affects the older engine. I would normally phone the service department if I wanted to contravene the Manufacturer Advice. 7 hours ago, T510 said: A change in the SportPlus4 formula (if there was one, I don't know) doesn't make previously suitable oils no longer perform at the level required. You wouldn't think so when it was supplying so many 912s, however we're talking about one phone call here; not the end of the earth. Just a matter of interest; if the manufacturer has your details linked to tghe engine, you would normally get information relating to your engine direct based on the oil manufacturer discussions with the engine manufacturer.They usually get their heads together first on the degree of the problem, and what the owner needs to do, then decide who is going to communicate.
Blueadventures Posted July 6 Posted July 6 4 hours ago, FlyBoy1960 said: perhaps they have a different standard in Japan because they don't have the sport plus oil available in that market ? On 8th April 2015 the second generation blend of the Sport Plus 4 oil was advised; likely due to market requirements and / or engine needs to better reaching the TBO in good order. 2
skippydiesel Posted July 6 Author Posted July 6 21 minutes ago, Blueadventures said: On 8th April 2015 the second generation blend of the Sport Plus 4 oil was advised; likely due to market requirements and / or engine needs to better reaching the TBO in good order. Where do you get this from; Read & Understand FlyBoy 1960 excellent history of Rotax Oil & AeroShell Sport Plus 4.(ASSP4) If an oil meets or exceeds the manufactures specification, it does not matter who makes it, what its called or the colour if the container it comes in. Sure we all have our favorite (trusted) brands - thats fine as long as the above is met. Rotax were happy to advise the specifications their engine owners should go for. As there was no alternative (AeroShell or similar product back then) thats what owners did and it all worked out just fine, as long as the owner/operator was burning ULP or not more than (if memory serves) 30% AvGas. Those wishing to use 100% AvGas or in excess of the 30% presented a problem, as the motorcycle oils, that met the Rotax specification, were not formulated to deal with the high lead contamination delivered by AvGas. The main, not only problem, with AvGas & Rotax 9's is the build up of lead in the gearbox - hense the 600 hr inspection of the same (1000 hrs for ULP). ASSP4 first became available, in large part to address the needs of owners wishing to us AvGas (I suspect mostly N American) It may be a coincidences but I feel it was about the time that that Rotax started to suggest that not using their OM products may lead to engine failure/shortened service life (scare tactics). The published oil specs. no longer appeared, replaced by ASSP4 For the most part, owners who were happy with the motorcycle oil kept using it to good effect (cant remeber but likly cheaper than ASSP4) and some with particularly long lived engines are still doing so. Much of this went on when a Rotax engine TBO was 600 hrs, with incremental increases over 20 years to 2000 hrs - an unlikly progression if the wrong oil was being used by the fleet. Rotax engines routinely exceed TBO, without costly life extending interventions, in part because owners adhered to the earlier (motorcycle) oil specification advise and have continued to do so, with the advent of ASSP4 (and the no longer published oil specifications). I do not recomend using other than ASSP4, however I do believe that someone who is able to find the earlier Rotax oil spec and match it to a current motorcycle oil, could do so, as long as AvGas is not a significant part of the fuel used. 😈
skippydiesel Posted July 7 Author Posted July 7 Addition to above post; Most of comment is only relevant to experimental/homebuilt Rotax powered aircraft. Factory or certified aircraft/engines, will have to stick to manufactures instructions/requirements.😈
turboplanner Posted July 7 Posted July 7 On 06/07/2026 at 9:04 PM, skippydiesel said: Where do you get this from; Read & Understand FlyBoy 1960 excellent history of Rotax Oil & AeroShell Sport Plus 4.(ASSP4) If an oil meets or exceeds the manufactures specification, it does not matter who makes it, what its called or the colour if the container it comes in. Sure we all have our favorite (trusted) brands - thats fine as long as the above is met. Rotax were happy to advise the specifications their engine owners should go for. As there was no alternative (AeroShell or similar product back then) thats what owners did and it all worked out just fine, as long as the owner/operator was burning ULP or not more than (if memory serves) 30% AvGas. Those wishing to use 100% AvGas or in excess of the 30% presented a problem, as the motorcycle oils, that met the Rotax specification, were not formulated to deal with the high lead contamination delivered by AvGas. The main, not only problem, with AvGas & Rotax 9's is the build up of lead in the gearbox - hense the 600 hr inspection of the same (1000 hrs for ULP). ASSP4 first became available, in large part to address the needs of owners wishing to us AvGas (I suspect mostly N American) It may be a coincidences but I feel it was about the time that that Rotax started to suggest that not using their OM products may lead to engine failure/shortened service life (scare tactics). The published oil specs. no longer appeared, replaced by ASSP4 For the most part, owners who were happy with the motorcycle oil kept using it to good effect (cant remeber but likly cheaper than ASSP4) and some with particularly long lived engines are still doing so. Much of this went on when a Rotax engine TBO was 600 hrs, with incremental increases over 20 years to 2000 hrs - an unlikly progression if the wrong oil was being used by the fleet. Rotax engines routinely exceed TBO, without costly life extending interventions, in part because owners adhered to the earlier (motorcycle) oil specification advise and have continued to do so, with the advent of ASSP4 (and the no longer published oil specifications). I do not recomend using other than ASSP4, however I do believe that someone who is able to find the earlier Rotax oil spec and match it to a current motorcycle oil, could do so, as long as AvGas is not a significant part of the fuel used. 😈 The most spectacular version of this I've even heard of came from a Bull Dozer owner who was cutting a dam for me. I was showing him my International BTD3 and he noticed I had a single grease can with gun. He pointed to his Cat D7 which towered over the old BTD and said "I used to think Caterpillar were over the top with their one specification here, another there, another somewhere else so I just used the one can. It wrecked the bull gear; cost me $45,000.00. Now I just send a message with the latitude and longitude and "grease the dozer" and a Cat truck comes out aand does it - a lot cheaper.
skippydiesel Posted July 7 Author Posted July 7 2 minutes ago, turboplanner said: The most spectacular version of this I've even heard of came from a Bull Dozer owner who was cutting a dam for me. I was showing him my International BTD3 and he noticed I had a single grease can with gun. He pointed to his Cat D7 which towered over the old BTD and said "I used to think Caterpillar were over the top with their one specification here, another there, another somewhere else so I just used the one can. It wrecked the bull gear; cost me $45,000.00. Now I just send a message with the latitude and longitude and "grease the dozer" and a Cat truck comes out aand does it - a lot cheaper. Other than telling some tangential story about heavy equipment - What is your point?😈
skippydiesel Posted July 7 Author Posted July 7 Just now, turboplanner said: I thought you might understand the parallel. There is no parallel - The failure of the dozer operator to meet the manufactures standards (assuming your obscure reference to a grease can, somehow caused the damage mentioned) is entirely the fault of the operator. 😈
facthunter Posted July 8 Posted July 8 I think you are oblivious to the Point that Turbs as Making about the situation where Oils are made for different conditions and when those conditions vary a lot, it's difficult to get ONE formulation to cover all Purposes. A Limslip Differential is a case in Point where a Hypoid drive requires a GL5 spec oil and Most Limslips require a GL4. Combined Engine Gearbox and clutch requires a Compromise oil. where if the Parts were Separated as to the OIL used, they could be better lubed with a more specific oil., Most Cars have separated Engine, Trans and differential oil types,. In the Mid 70s engine oils had to be able to cope with Cat. Converters and had to have some friction Modifiers removed. They THEN became unsuitable for gear boxes. Not everyone Knows this and still follows the original Makers recommendations in cars Motorbikes & tractors etc and thereby risks severe damage to gearboxes. and diffs. Nev
FlyBoy1960 Posted July 8 Posted July 8 as someone famous once said.. "Oils ain't oils - Sol" unless it's Valvoline 1 1
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