[Vwdiesel] Risks of straight weight

[slatersfb@aol.com]

-----Original Message-----
From: Val Christian <val at mongobird.com>
To: slatersfb at aol.com; vwdiesel at vwfans.com
Sent: Wed, 5 Oct 2005 09:03:29 -0400 (EDT)
Subject: Re: [Vwdiesel] Risks of straight weight


> 
>  They took a quart of oil, used in 
>     corporate fleet equipment, and stirred in a pound of "fines"
>     which is another way of saying dirt and soil and sand.
>     At 70F, the oil held the pound of "stuff" and visibly flowed 
>     OK, and I was told would wear test acceptably.
> 
>     The oil was chilled to 0F, and it was like tar.  I was told 
>     that the same oil, at 0F would only hold about two table
>     spoons of dirt.  Something like a 30:1 different going from
>     70F to 0F.
>  
> *********************************
>  
> Val,
>  
> What does it mean that the oil wouldn't hold the fines at 0F? Where did the 
excess go & how do the fines or absence thereof effect wear test?

    My take is that you don't want dirty oil when it's cold.

    If I'm going up north in Jan or Feb, I change the oil first.

    Mostly, I just found the demonstration very impressive.  I didn't
    know that a qt of oil would hold so much stuff.  And I didn't 
    realize how quickly it precipated out as the temps dropped.

>  
> Two years ago I was using 15w40 all year. (91 Jetta 1.6 N/A) I do all highway 
driving and changed oil & filter every 3,000 miles. At the 3,000 mile point that 
oil was beat. I could hear it in the engine. Lots of internal clattering and 
occasional intermittent lifter collapse at idle speed. 
> WalMart sells Mobil1 for $21 US for a 5 quart bottle. After 2 years and using 
only my back yard perceptions, I think it is better oil than any dino oil I have 
ever used. Starts in cold (-20F) are instant. Cranking speed is the same as it 
is in summer. After 4,000 miles internal engine noises are about  the same as 
when I first dumped it in.  
> I suppose I won't know about sludge and swarf internally til it's time for 
rebuild, but synthetic oil has a good reputation in that regard. We'll see. So 
far, I'm impressed.

    Why wait?  How about popping the valve cover?  Or putting a small 
    inspection mirror in there, to see what the cyl head top is collecting?

    What interval do you use with the Mobil 1?  Any oil condition
    testing (poor man's blotter, even)?

    If I had an engine with allot of blow-by, and perhaps marginal 
    compression, I'd be less inclined to use synthetics.

    Mobil 1 is a well regarded product, and I'm sure it will do 
    well for you.  Any more data to share with us on your experience?

    Val

  *******************
I've had the V/C off a couple of times and all I see is black oil. No sludge or any of 
that milk shake stuff at all.
Engine is fresh - about 60k miles. Never took actual compression test with an instrument, 
but I can hear the load on starter as each cylinder comes up on compression. They are all even any ways.
Blow by is minimal - no oil on air filter. I've never had to add oil between changes. 
I change Mobil1 at 4,000 miles with Mann filter. Oil still seems to be performing like new, but
I'm afraid of carbon build up in filter and subsequent bypass.
My other vehicle - 81 pickup - 1.6 N/A - had broken and stuck rings when I bought it in 1986. 
This I attributed to the P/O's use of oil not diesel rated. New head, rings & bearings in '88. 
I use Mobil1 in this also, and plan to put 
serious mileage on it this winter, save the Jetta from the salt as much as possible.
I had no idea that oil lost it suspension abilities as temp dropped. Curiouser & curiouser.
I never heard of blotter test till I came to this forum, and I don't know what is involved. 
Care to enlighten me?
 
Bob in the Entire State