I tested the ability of these two engine flushes to dissolve very baked on motor oil varnish. The BG EPR was purchased this month and the Amsoil Engine Flush is around 10 years old.
First, I needed two blobs of varnish so I created them. I put two drops of same size made of Mobil 1 20W-50 Motorcycle oil on a thick steel plate. Then I heated it from below as rapidly as my blow torch could do. I heated it as evenly as I could. The oils did not catch on fire despite getting them well above flash point. After 7 to 8 minutes of heating the plate and ensuring that no liquid oil remained, I let the plate cool down.
Side note: I’ve never tested this oil before or one that viscous. I was amazed at how black the varnish it formed was. The oil has a very low volatility and so more of it stuck around on the plate, allowing more of the molecules to turn into varnish rather than evaporate and leave the scene. This behavior contrasts with that of M1 0W-20 EP.
BG EPR was put on one varnish spot and Amsoil Engine Flush on the other. No mixing was allowed. Two q-tips were assigned to a spot which I used to wipe the spots, with as equal as possible force, distance, and speed. I only used one surface of the q-tip end to wipe the varnish to make it much easier to compare the darkness each would get from dissolving the dark varnish.
Results:
In the first 30 seconds or so of wiping, neither cleaner cleaned enough to show any varnish on the q-tips. Then Amsoil flush’s q-tip started to get a little bit of color on it while BG EPR’s did not. It was looking like there was going to be a clear winner but the test was still far too short. I wiped for several minutes, then covered the spots with aluminum foil to let the solvents soak and not evaporate. At the end of the first day’s wiping, BG was starting to catch up to Amsoil based on the darkness of the q-tips. A day later I wiped some more. Then the two q-tips ended up with approximately the same darkness. I put fresh solvent on each spot, covered them with foil, and then wiped again the next day. The q-tips got slightly darker and remained so similar that I couldn’t tell which one was darker. It became obvious that:
1. The solvents performed approximately equally well in the end but Amsoil dissolved the varnish at a faster rate initially. This is probably a benefit when used for a 10 minute flush prior to an oil change.
2. This varnish was extremely hardened and likely nothing short of caustic solvents has a chance of dissolving them completely. I wanted the varnish to be hardened enough that it would not be so easy for the solvents to dissolve that both oils easily completely dissolved it. It would probably be good for me to test on varnish that is less hardened than it was in this test. I did test BG EPR on a much less hardened varnish from M1 0W-20 EP and it dissolved it completely in a few seconds of wiping.
The ingredients of these solvents are quite different, as are their odors. BG has a more strong and foul odor.
Pictures :
Before solvents added:
Pictures from after the test:
In the next two, you can see that their is a visible thickness to the varnish spots.
First, I needed two blobs of varnish so I created them. I put two drops of same size made of Mobil 1 20W-50 Motorcycle oil on a thick steel plate. Then I heated it from below as rapidly as my blow torch could do. I heated it as evenly as I could. The oils did not catch on fire despite getting them well above flash point. After 7 to 8 minutes of heating the plate and ensuring that no liquid oil remained, I let the plate cool down.
Side note: I’ve never tested this oil before or one that viscous. I was amazed at how black the varnish it formed was. The oil has a very low volatility and so more of it stuck around on the plate, allowing more of the molecules to turn into varnish rather than evaporate and leave the scene. This behavior contrasts with that of M1 0W-20 EP.
BG EPR was put on one varnish spot and Amsoil Engine Flush on the other. No mixing was allowed. Two q-tips were assigned to a spot which I used to wipe the spots, with as equal as possible force, distance, and speed. I only used one surface of the q-tip end to wipe the varnish to make it much easier to compare the darkness each would get from dissolving the dark varnish.
Results:
In the first 30 seconds or so of wiping, neither cleaner cleaned enough to show any varnish on the q-tips. Then Amsoil flush’s q-tip started to get a little bit of color on it while BG EPR’s did not. It was looking like there was going to be a clear winner but the test was still far too short. I wiped for several minutes, then covered the spots with aluminum foil to let the solvents soak and not evaporate. At the end of the first day’s wiping, BG was starting to catch up to Amsoil based on the darkness of the q-tips. A day later I wiped some more. Then the two q-tips ended up with approximately the same darkness. I put fresh solvent on each spot, covered them with foil, and then wiped again the next day. The q-tips got slightly darker and remained so similar that I couldn’t tell which one was darker. It became obvious that:
1. The solvents performed approximately equally well in the end but Amsoil dissolved the varnish at a faster rate initially. This is probably a benefit when used for a 10 minute flush prior to an oil change.
2. This varnish was extremely hardened and likely nothing short of caustic solvents has a chance of dissolving them completely. I wanted the varnish to be hardened enough that it would not be so easy for the solvents to dissolve that both oils easily completely dissolved it. It would probably be good for me to test on varnish that is less hardened than it was in this test. I did test BG EPR on a much less hardened varnish from M1 0W-20 EP and it dissolved it completely in a few seconds of wiping.
The ingredients of these solvents are quite different, as are their odors. BG has a more strong and foul odor.
Pictures :
Before solvents added:
Pictures from after the test:
In the next two, you can see that their is a visible thickness to the varnish spots.
