What is this cheesy material in my oil cooler?

CharlieTango said:
I bought it new and it stayed cool for almost 2 years.

It has Aeroshell Sport in it now but mostly used Mobile 1 Full syn.
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Both of those are very well accepted oils for the 912 series, and I have never heard of either oil causing any issues.

Will be very interested in what happens with this.
 
bullwinkle said:
Both of those are very well accepted oils for the 912 series, and I have never heard of either oil causing any issues.

Will be very interested in what happens with this.
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Until I hot-flushed the oil-cooler I didn't have a clue that this contaminant was prevalent in my oil-cooler.

I have never heard of anyone esle hot-flushing their Rotax oil-cooler, maybe this material isn't rare. There are a lot of 912s with my oil cooling problem.
 
CharlieTango said:
I bought it new and it stayed cool for almost 2 years.

It has Aeroshell Sport in it now but mostly used Mobile 1 Full syn.
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Lose the junk synthetic oils, especially if you are running 100LL. Mobil ended up withdrawing Mobil 1 from the aircraft engine market, and buying a lot of Continental engines, because of the deposits it was leaving in engines.

If you are burning 100LL, Phillips 20/50 and Cam Guard.
 
Henning said:
Lose the junk synthetic oils, especially if you are running 100LL. Mobil ended up withdrawing Mobil 1 from the aircraft engine market, and buying a lot of Continental engines, because of the deposits it was leaving in engines.

If you are burning 100LL, Phillips 20/50 and Cam Guard.
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I don't burn any 100LL. What you say about Mobil 1 is interesting apparrently it applies to AV1 where I was using 4T motorcycle racing oil.

Thanks
 
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CharlieTango said:
I don't burn any 100LL. What you say about Mobil 1 is interesting apparrently it applies to AV1 where I was using 4T motorcycle racing oil.

Thanks
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Rotax recommends not using the full synthetic if you are burning the leaded stuff. Or, if you have to, more frequent oil changes. Apparently, the synthetic doesn't do as well at keeping the lead sludge in suspension.

The AeroShell Sport 4 seems to be one of the better choices out there at the moment.
 
CharlieTango said:
I don't burn any 100LL. What you say about Mobil 1 is interesting apparrently it applies to AV1 where I was using 4T motorcycle racing oil.

Thanks
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What are the differences? The base stock to every synthetic oil on the market is identical.
 
Henning said:
What are the differences? The base stock to every synthetic oil on the market is identical.
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I would guess more motorcycle type additives in the 4T and the contaminent that I'm seeing is bright yellow. The AV1 complaints talk about black sludge.

If this contamination is from the oil and if it is from the base stock vs additives is another question.
 
CharlieTango said:
I would guess more motorcycle type additives in the 4T and the contaminent that I'm seeing is bright yellow. The AV1 complaints talk about black sludge.

If this contamination is from the oil and if it is from the base stock vs additives is another question.
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How many hours are on your ride? (Or, at about how many hours did you notice the temperature climbing?)
 
CharlieTango said:
Oil started getting hot after 300+hours
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Hmmm. Not in a CT, but I am pushing 500 hours and still have aluminium tape on the radiator to keep water / oil temperatures up (oil cooler was relocated behind the radiator to keep it warmer). I used the Mobile 1 motor cycle stuff until last summer when I switched to Aeroshell sport 4, but I don't know what kind of oil the previous owners used.
 
1600vw said:
From the looks of it, something has bought the farm. Keep us posted as to what you find. But I think something has gone bad and these are pieces of that part. It could be an oil pressure relief valve of some sort. With it being a 912 it could be any number of things.
Water in the oil it is not. Antifreeze in the oil it is not. Antifreeze in your oil will make the oil look like milk from the water. Water in fuel will not cause this either.
Your engine ate itself somewhere. I would lay 5 bucks on it.

Tony
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Tony,

What other things, given its a 912 could it be? I have the contaminants now and they seem like pieces of plastic.
 
In my experience, the only things on a Rotax 912 that are made out of plastic that color yellow are the protective shipping caps and covers.

-Rich
 
The engine is making plastic from oil and combustion by products, the question is what else? Coolant? Personally I would send the stuff to Blackstone and ask for an analysis.
 
Henning said:
The engine is making plastic from oil and combustion by products, the question is what else? Coolant? Personally I would send the stuff to Blackstone and ask for an analysis.
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When I had some stuff in my filter Blackstone recommended that I send it to this guy for analysis:

Howard Fenton
7820 S. 70th East Avenue
Tulsa, OK 74133
nine 1 eight dash four 9 two dash five 8 four 4

I believe he charges $25.

Jim
 
CharlieTango said:
We are doing a hot flush on my oil cooler. My Rotax 912 ULS now gets hot oil temps when climbing.

This yellow material is a mystery, does anyone know what it is?
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It looks EXACTLY like the stuff I flushed from the cooling system of my car yesterday. Exactly.

Now, why it would show up in my cooling system and your oil system :dunno:

On the bright side, my heater actually puts out heat now - unlike last winter.
 
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