John001
28th Apr 2006, 14:11
Hello,
Could anyone someone can shed some light on this oil analysis? I’m somewhat concerned about the levels of metal (particularly lead) concentration in the oil:
Firstly Engine type is a 1972 Limbach (VW engine converted to single magneto) 1700cc.
Aircraft type is a 1972 Scheibe ‘Falke’ motorglider.
The oil was analysed for, among many other metals, Iron, copper, lead and magnesium content.
The company who ran the analysis (BHP here in Limerick, Ireland) also provided the following data in relation to these metals and their concentration levels:
Iron: “Generally results from ring, bore, cam tappet or crank wear. Permissible maximum is about 100ppm (parts per million)”.
Copper:”Originates from copper/lead bearings or syncromeshes in gearboxes. Working maximum is 50ppm”.
Lead: “Usually derived fro lead/tin bearings or copper/lead main bearings. Also used as octane boosting additive in petrol. A level over 50ppm indicates a problem however petrol engines running on leaded fuel can show levels of several thousand ppm”.
Three oil tests were done over the past year:
Test 1 10-05-05(NB- This test was run several hours after a piston & barrel change)
Iron 61ppm
Copper 11ppm
Lead 1859 ppm
Magnesium 300ppm
*NOTE- Engine block is Magnesium.
Test 2 22-03-06 ( The plane had done about 60 hours since test 1)
Iron 156ppm
Copper 21ppm
Lead 839ppm
Magnesium 35ppm
Test_3 23-03-06 ( The engine had been run for about 1hour since test 2 and the OIL HAD BEEN CHANGED AFTER TEST 2)
Iron 91ppm
Copper 6ppm
Lead 264ppm
Magnesium 17ppm
The above would suggest seriously high levels of lead if using unleaded fuel which we are (Mogas).”Maximum 100ppm” according to the analysts. However we are also adding the following to the fuel :
-Wynns octane booster
-Castrol valvemaster
However neither the Wynns nor the Valvemaster have any lead in them (as far as I can ascertain!?).
As you can see, the lead levels are falling significantly with each test but are still way above the 100ppm recommended maximum. So, what I’d really like to know is:
1) If the lead is originating from bearing wear, why aren’t there other wear metals present??
2) Do Wynns or Castrol really have absolutely no lead in them?
3) Do lead levels over 100ppm necessarily indicate a problem?
I have the full report on the oil analysis here if anyone needs more information (there are 16 metals altogether). Hopefully someone can shed some light on this. The aircraft is fully compliant and the sun is shining and… you know the rest!! :)
regards,
John
Could anyone someone can shed some light on this oil analysis? I’m somewhat concerned about the levels of metal (particularly lead) concentration in the oil:
Firstly Engine type is a 1972 Limbach (VW engine converted to single magneto) 1700cc.
Aircraft type is a 1972 Scheibe ‘Falke’ motorglider.
The oil was analysed for, among many other metals, Iron, copper, lead and magnesium content.
The company who ran the analysis (BHP here in Limerick, Ireland) also provided the following data in relation to these metals and their concentration levels:
Iron: “Generally results from ring, bore, cam tappet or crank wear. Permissible maximum is about 100ppm (parts per million)”.
Copper:”Originates from copper/lead bearings or syncromeshes in gearboxes. Working maximum is 50ppm”.
Lead: “Usually derived fro lead/tin bearings or copper/lead main bearings. Also used as octane boosting additive in petrol. A level over 50ppm indicates a problem however petrol engines running on leaded fuel can show levels of several thousand ppm”.
Three oil tests were done over the past year:
Test 1 10-05-05(NB- This test was run several hours after a piston & barrel change)
Iron 61ppm
Copper 11ppm
Lead 1859 ppm
Magnesium 300ppm
*NOTE- Engine block is Magnesium.
Test 2 22-03-06 ( The plane had done about 60 hours since test 1)
Iron 156ppm
Copper 21ppm
Lead 839ppm
Magnesium 35ppm
Test_3 23-03-06 ( The engine had been run for about 1hour since test 2 and the OIL HAD BEEN CHANGED AFTER TEST 2)
Iron 91ppm
Copper 6ppm
Lead 264ppm
Magnesium 17ppm
The above would suggest seriously high levels of lead if using unleaded fuel which we are (Mogas).”Maximum 100ppm” according to the analysts. However we are also adding the following to the fuel :
-Wynns octane booster
-Castrol valvemaster
However neither the Wynns nor the Valvemaster have any lead in them (as far as I can ascertain!?).
As you can see, the lead levels are falling significantly with each test but are still way above the 100ppm recommended maximum. So, what I’d really like to know is:
1) If the lead is originating from bearing wear, why aren’t there other wear metals present??
2) Do Wynns or Castrol really have absolutely no lead in them?
3) Do lead levels over 100ppm necessarily indicate a problem?
I have the full report on the oil analysis here if anyone needs more information (there are 16 metals altogether). Hopefully someone can shed some light on this. The aircraft is fully compliant and the sun is shining and… you know the rest!! :)
regards,
John