moly basics

Does oil alone clean and condition seals???

I decided to try an experiment on what motor oils and additives will do to your engine seals and here's some of the results I found.

I bought 6 brand new standard O ring seals from AutoZone and measured each out. All of them measured 3mm exactly on this gauge.

I then put 5 in different various oils. Maxlife, Pennzoil HM, Amsoil (full synth) , Mobil (supersyn

full synth) Schaeffers(blend), and the last was in the Schaeffers Fuel/Oil treatment 131 Neutra.

After 2 weeks soaking in these fluids at ambient temps, not being disturbed, I then pulled each out

and re-measured. I found all of the seals in the motor oils had not changed in measurement at all.

I did find the 131 Neutra had caused the seal to swell about 3.25 mm to slightly under a

3.5 (close as a measurement I could obtain with this tool). Either way, it does show an increase

but not to a point of damage due to oversize. I rechecked the size of these seals again 2wks

later and found them to be maintaining the same size and condition.

Here is a picture of this seal.

So at this point, my personal conclusion for this test is that motor oils, full or standard dino oil

does not condition seals. This would also stand behind the reasons as to why the Schaeffers

131 Neutra helps stop valve stem leaks (puffing smoke in the morning) whereas motor oils alone

don't.

Now for the 2nd part of this,

I took used valve stem seals from a machine shop that had build up on them and

put them in some fresh oils from each bottle mentioned before.

Now of course you scientific guys will catch this as I know I can't fool you, the two

on the right end are not the same as I didn't have access to all the same. But for

this test, I figured they were pretty close to being grimy enough to provide evidence

as to how well oils clean.

The Test

I placed each one of these seals in a motor oil. Again,

Maxlife, Pennzoil HM, Amsoil (full synth) , Mobil (supersyn

full synth) Schaeffers(blend), and the last was in the Schaeffers Fuel/Oil treatment 131 Neutra.

Again, 2wks at room temp, undisturbed, I then pulled out each one, examined the seals and

examined the oil.

Here is what I saw left in each oil.

Maxlife Pennzoil HM

Amsoil Mobil1supersyn

Schaeffers Neutra 131 Schaeffers

The interesting thing I saw was that any oil that had any kind of Synth, (ester/pao)

seemed to do well in cleaning. Amsoil Showed the best in cleaning

whereas Mobil's supersyn and Schaeffers seemed close to the same.

As for the High Mileage oils by Pennzoil and Maxlife, both seemed not to fair as well

which I somewhat expected from maxlife but didn't know about Pennzoil.

As for Neutra, it seemed to do a good job as well. The interesting thing was it

had dispersed out from the seal and had it suspended throughout the fluid as

well having conditioned it with a slight increase of size of not more than .25mm.

One of the important things that is happening here is that when you clean a seal, remember that

the seal has endured extreme levels of temps and has coked up therefore the elasticity of

the seal will tend to be harden. None of the oils themselves soften the seals therefore

would have created a leaking situation had they cleaned the seal without conditioning.

This in my opinion is why so many people tend to find leaks with synth's because

it cleans the seals, but without conditioning it now has a clean harden seal

where it can pass by, as before the grime and such that was covering the seal was acting like

a seal in itself.

Now keep in mind that because of the different seals, each not exactly the same,

Some of these conclusions would vary a little, but I believe it does demonstrate to

some degree how the different base oils/additives show different degrees of cleaning action.

After all said and done, I now agitated the 3 synth/blend oils and the 131 neutra in a circular motion

for 1 minute then poured into a coffee filter to see how they compared after poured out.

Here's what they looked like.

Amsoil

Mobil 1

Schaeffers Blend

Neutra 131

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