<VV> Amsoil Products (was: Get your Oil)

[Dale Dewald]

Hello Folks,

There are several Amsoil products specifically recommended by them for use 
in flat-tappet engines:

1) Type AMO 10W-40 Premium Protection

2) Type ARO 20W-50 Premium Protection

3) Type HDD 5W-30 HD Diesel

All of the above contain 1267ppm P and 1378ppm Zn and would need no 
supplemental additives.  The Amsoil people recommended type HDD 5W-30 for 
the Corvair, but in my own Corvairs, I use another Amsoil product; Type ACD 
10W-30/SAE30 Diesel, which is actually a straight 30 weight synthetic oil, 
but meets the API 10W-30 specifications for viscosity. It also has 1267ppm 
P and 1378ppm Zn. We do not drive our Corvairs in winter (salt!!), and so 
do not really need the low temperature properties of a 5W-30 oil.

I would be cautious about adding ZDDP to any motor oil on a regular 
basis.  There are a lot of other additives (detergents, antioxidants, acid 
neutralizers, etc) that are formulated for a specific oil as a 
package.  While adding ZDDP may improve the wear resistance of an oil, it 
may also bind up the other additives and lead to damage in the form of 
sludge or deposit formation, corrosion by combustion by products, or rapid 
viscosity changes.  There was a study done on this a while back, but I 
cannot find a reference to it right now.

Those of you who would like to buy oil off the shelf at the local discount 
store should check on the remaining stock of Mobil 1 High Mileage, which 
has been discontinued.  My local Wal-Mart has this on clearance:

http://www.mobil.com/USA-English/Lubes/PDS/NAXXENPVLMOMobil_1_High_Mileage_Oil.aspx

I took note that it is rated API SL/CF without the ILSAC-GF4 "energy 
saving" specification.  I would suspect that it has a reasonable amount of 
ZDDP, but I could not find specific data on this at the ExxonMobil web site.

At 03:11 2/23/2011 -0500, Mark Durham wrote:
>Everyone; The 10 W 40 might be a better bet. If you have paid any
>attention to Richard Widman's oil articles, the Corvair Engine was
>designed to flow 30 WT oil.
>
>Richard says: (copied from his article) As an example, the 1960
>Corvair Service Manual recommends SAE 10W-30 or SAE 30 for most
>operating conditions anticipated. There were no 5W-30 or 0W-30 oils to
>recommend in those days, but Chevrolet apparently designed this engine
>to run on oil that is between 9.3 cSt and 12.5 cSt in the bearings.
>This means that as long as our oil is in that viscosity range at the
>100 degree C test, we are minimizing the wear in the engine. When the
>oil viscosity is above or below that range the engine will have
>additional wear.
>
>Also, you have to think about the ability to flow oil to remove heat.
>You put a thicker oil thru the oil cooler it passes less heat due to
>less oil flow. You push thicker oil out the push rods to the rockers,
>you get less flow, and less lubrication on the drip system out there,
>and less cooling so the engine runs hotter all the time. Less oil will
>flow through the bearings and splash all over in the case, so it takes
>away less heat.

 >>snip<<

Dale Dewald
Hancock, MI