So yesterday was nice and mild, and good oil change weather. so i drained the FM 50:50 dino 5w30/ synth 5w30, with 3500 miles, per Subaru Canadian schedule. the FM is fortified with 200ml. MoS2.
I'm using purolator pure one 14610, so i thought i could keep it in place for another cycle. New fill of FM dino QS 5w20/ synth ST 5w30, again with 200 ml MoS2. Engine ran nice after the oil change. So...
This morning the temp is at the freezing point, and i'm anxious to see how nice the FM works slightly cold. I start the engine, and immediately there is a loud banging, BANG, BANG, BANG, BANG, BANG, after 10 -15 seconds it quiets down and starts purring.
It is not like piston slap, which goes like BOK BOK BOK BOK BOK, but a BANG BANG BANG BANG BANG, and then quickly gets quiet after 10-15 seconds, again NOT like piston slap.
I think what happened is the MoS2 (Promoly) is forming clumps, and I am using a filter with very fine holes, and the filter is getting clogged, so the engine is starved for oil, and the pistons are banging against something, until oil gets in via the bypass valve.
So at lunch, I drove home, mixed 50:50 Formula Shell full synthetic purchased at Canadian Tire, 5w20/5w30, to create a 5w25, got out a new Pure One filter, and drove out to Wally Mart, and had them drain the oil, replace the filter, and refill with
Shell synth 5w25. I don't regard this as a Frankenmix, because the oil is of the same type and same manufacturer. After work it was getting colder and colder, and the car was good and cold. This time when I started it, the engine was purring, and sounded real nice and quiet.
Lesson: when the research guys at BITOG say that MoS2 will clump, that means do not use it. When board members of BITOG say run pure synth in winter for best cold protection, then run pure synth in winter for best cold protection. I had the Wall Mart people return my filter, so I can cut it open, examine the filter medium, and see whether it appears to be clogged with MoS2, because I'm absolutely sure that is what happened.
I'm using purolator pure one 14610, so i thought i could keep it in place for another cycle. New fill of FM dino QS 5w20/ synth ST 5w30, again with 200 ml MoS2. Engine ran nice after the oil change. So...
This morning the temp is at the freezing point, and i'm anxious to see how nice the FM works slightly cold. I start the engine, and immediately there is a loud banging, BANG, BANG, BANG, BANG, BANG, after 10 -15 seconds it quiets down and starts purring.
It is not like piston slap, which goes like BOK BOK BOK BOK BOK, but a BANG BANG BANG BANG BANG, and then quickly gets quiet after 10-15 seconds, again NOT like piston slap.
I think what happened is the MoS2 (Promoly) is forming clumps, and I am using a filter with very fine holes, and the filter is getting clogged, so the engine is starved for oil, and the pistons are banging against something, until oil gets in via the bypass valve.
So at lunch, I drove home, mixed 50:50 Formula Shell full synthetic purchased at Canadian Tire, 5w20/5w30, to create a 5w25, got out a new Pure One filter, and drove out to Wally Mart, and had them drain the oil, replace the filter, and refill with
Shell synth 5w25. I don't regard this as a Frankenmix, because the oil is of the same type and same manufacturer. After work it was getting colder and colder, and the car was good and cold. This time when I started it, the engine was purring, and sounded real nice and quiet.
Lesson: when the research guys at BITOG say that MoS2 will clump, that means do not use it. When board members of BITOG say run pure synth in winter for best cold protection, then run pure synth in winter for best cold protection. I had the Wall Mart people return my filter, so I can cut it open, examine the filter medium, and see whether it appears to be clogged with MoS2, because I'm absolutely sure that is what happened.
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