MB65E Posted August 14, 2016 Report Posted August 14, 2016 So this weekend I dove into my oil pan gasket replacment on my 94 318i German road oiler. I'm glad I make a living at working on airplanes and not cars... I have always run M1 0w-40 synthetic oil in it. With 175k I wanted to switch to a 20w50 synthetic due to some possible valve guide ware. The search basically ended up with nothing except royal purple at $10 per qt. No thanks. So lots of guys run Shell T6 rotella synthetic with the pre y2k ZDDP zinc content. All of the old oils had much more additives in them than they do now. Prior to 2000 regulation has cut the ZDDP in half. This got me thinking... Does anyone know the ZDDP content in our aircraft engine oils? I'm wondering if this is the simple reason our tappets are turning engines into scrap metal. Probably should have used the search function. -Matt 1 Quote
N201MKTurbo Posted August 14, 2016 Report Posted August 14, 2016 ZDDP is an ash forming extremely pressure additive. It is not found in ashless despersant aviation oil. Things like Cam gaurd and Lycoming oil additive may contain ZDDP and TCP. 1 Quote
MB65E Posted August 14, 2016 Author Report Posted August 14, 2016 Thanks, makes sense. After all the running around today, I was about ready to use the aeroshell 100+ I had in the trunk for the Mooney. -Matt Quote
nels Posted August 14, 2016 Report Posted August 14, 2016 ZDDP is available in a small, about 4 oz bottle, for use as a cam and flat tappet additive. I think it is a zink enhanced treatment.Is there a problem with adding it to an aircraft engine? I agree, the new oils are formulated differently now and that is the reason for new engines in autos and aircraft going to roller cam shaft sets. In the early 1950s the auto industry had a severe problem with cam failures and the petroleum industry added zink to cure the problem. Quote
geoffb Posted August 15, 2016 Report Posted August 15, 2016 Valvoline Racing 20-50 is what all of us old BWM drivers with M30s seem to like. Air cooled guys too. Word is it has the highest ZDDP available. Leaks out of my 653CSi, just fine. 2 Quote
mike_elliott Posted August 15, 2016 Report Posted August 15, 2016 On 8/14/2016 at 8:40 AM, nels said: In the early 1950s the auto industry had a severe problem with cam failures and the petroleum industry added zink to cure the problem. And this 1950's engineering science haunts aircraft cams to this day, unfortunately. Oh wait, Lycoming fixed it with a roller cam....well sort of... 1 Quote
Bob_Belville Posted August 15, 2016 Report Posted August 15, 2016 On 8/14/2016 at 0:58 AM, N201MKTurbo said: ZDDP is an ash forming extremely pressure additive. It is not found in ashless despersant aviation oil. Things like Cam gaurd and Lycoming oil additive may contain ZDDP and TCP. I run IO360 with AS W100 (AD) and Camguard. Zinc in Blackstone oil analysis is only 3 ppm. (Camguard does increase analysis for calcium and phosphorus.) 1 Quote
N201MKTurbo Posted August 15, 2016 Report Posted August 15, 2016 (edited) 11 minutes ago, Bob_Belville said: I run IO360 with AS W100 (AD) and Camguard. Zinc in Blackstone oil analysis is only 3 ppm. (Camguard does increase analysis for calcium and phosphorus.) I don't know what Cam Guard uses. I would suspect that if you are seeing a rise in Phosphorus then they are using TCP. https://en.wikipedia.org/wiki/Tricresyl_phosphate https://en.wikipedia.org/wiki/Antiwear_additive TCP is another extreme pressure additive. Edited August 15, 2016 by N201MKTurbo Quote
Bob_Belville Posted August 15, 2016 Report Posted August 15, 2016 7 minutes ago, N201MKTurbo said: I don't know what Cam Guard uses. I would suspect that if you are seeing a rise in Phosphorus then they are using TCP. https://en.wikipedia.org/wiki/Tricresyl_phosphate https://en.wikipedia.org/wiki/Antiwear_additive TCP is another extreme pressure additive. I asked Blackstone whether the higher than average readings for those elements were due to Cam Guard and they confirmed that that is their experience. I suppose skunk oil peddlers do not publish their recipe. Kinda like grandma's red velvet cake. 2 Quote
MB65E Posted August 15, 2016 Author Report Posted August 15, 2016 Well the oil pan quit leaking. Oil filter housing profile gasket is next. Thanks for the discussion guys! -Matt 1 Quote
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