UK S2000 Viscosity discrepancies !

[Olas]

Originally Posted By: Shannow
Originally Posted By: Olas
Redline 5w30 is 3.8HTHTS and it won't shear with heat or fuel.


seriously, fuel won't change it's viscosity ?

How does that work ?


It can dilute but that's not the same thing. I read on here that raw fuel can attack/destroy VIIs, and redline doesn't have any.

 

[Olas]

Originally Posted By: bobbydavro
Originally Posted By: Olas
Redline 5w30 is 3.8HTHTS and it won't shear with heat or fuel.


The fact it is a high HTHS suggests to me that it will shear as its being propped up with a decent amount of VM to get that sort of number. Fuel doesnt shear, it dilutes.



The base gives it the characteristic, no VIIs needed

 

[kschachn]

Originally Posted By: Olas
It can dilute but that's not the same thing. I read on here that raw fuel can attack/destroy VIIs, and redline doesn't have any.


In the context of a Blackstone type analysis it most certainly is. You're saying that mixing a low-viscosity fluid with the oil will not lower its overall viscosity if you are testing Redline oil?

I'd like to read anything you can link that states VI polymers can be degraded by gasoline.

 

[Shannow]

Was a theme on BITOG at one stage that fuel broke polymers.

Seemed it was RLI, Redline, and IIRC Terry.

But Bruce 381 did some testing here
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/965379

And found same thinning effect from fuel whether it was straight, or VIIed...plain old dilution.

As an aside, if Olas' point WAS correct, what would it mean ?

The oil would still be thinned, not like you are going to put it on the stove, boil the fuel out and tip it back in.

 

[weasley]

Originally Posted By: Shannow
The oil would still be thinned, not like you are going to put it on the stove, boil the fuel out and tip it back in.


No need for that - the engine can boil away the fuel in use.... if given the opportunity. If the rate of dilution > rate of evaporation then you get an accumulation. Bobbydavro suggests that these engines can accumulate fuel if used in a certain way. Cold starts with short journeys will also do this, as will anything that messes with the fuelling.

 

[Olas]

Originally Posted By: kschachn
Originally Posted By: Olas
It can dilute but that's not the same thing. I read on here that raw fuel can attack/destroy VIIs, and redline doesn't have any.


In the context of a Blackstone type analysis it most certainly is. You're saying that mixing a low-viscosity fluid with the oil will not lower its overall viscosity if you are testing Redline oil?

I'd like to read anything you can link that states VI polymers can be degraded by gasoline.


What I'm saying is that the fuel won't shear the oil, so once the fuel has evaporated the Redline will return to its original, pre dilution viscosity. Other oils can have the fuel evaporate out of them but they do not return to the original state because the VIIs have been mechanically damaged y the presence of the fuel

 

[Olas]

Originally Posted By: Shannow
Was a theme on BITOG at one stage that fuel broke polymers.

Seemed it was RLI, Redline, and IIRC Terry.

But Bruce 381 did some testing here
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/965379

And found same thinning effect from fuel whether it was straight, or VIIed...plain old dilution.

As an aside, if Olas' point WAS correct, what would it mean ?

The oil would still be thinned, not like you are going to put it on the stove, boil the fuel out and tip it back in.


That was the thread I was thinking of but couldn't find! Thanks, Shannow

As an aside, if my point was correct, it would mean redline is 'better' in that it is not 'damaged' by fuel being present and then being removed.

 

[kschachn]

Originally Posted By: Olas
What I'm saying is that the fuel won't shear the oil, so once the fuel has evaporated the Redline will return to its original, pre dilution viscosity. Other oils can have the fuel evaporate out of them but they do not return to the original state because the VIIs have been mechanically damaged y the presence of the fuel


Where do you see that, or did I just miss it? Doesn't he say:

Quote:
Same or similar loss than the 10/30 which suggests to me that vis loss at least in a new oil due to fuel is due to just the lower vis of the fuel and is not due to fuel "solubilizing or hurting" the VII since the GPII had none.


Unless you are doing some sort of average molecular weight analysis on the polymer (HPLC??) I don't know how you would know. I've never see that suggested anywhere else, have you?

 

[Shannow]

Originally Posted By: Olas
Originally Posted By: Shannow
Originally Posted By: Olas
Redline 5w30 is 3.8HTHTS and it won't shear with heat or fuel.


seriously, fuel won't change it's viscosity ?

How does that work ?


It can dilute but that's not the same thing. I read on here that raw fuel can attack/destroy VIIs, and redline doesn't have any.


This is the thread that I was looking for, and just found

Originally Posted By: Terry
The key and newer idea you might be missing is the effect of aromatic damage to a certain molecules, and finding those chemistries that resist that damage better than the conventional formulating is currently aware of. I'm no formulator. I just test for them. Please get your boss to consider using our services so we can explain more.

Terry


http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/893267/7