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Re: Thermostat/Oil Cooler (story too long... but useful...)

Hey Leon- 

> > I just read an article on this question in the Gene Berg catalog. He 
>  > states that there is an decrease in engine life between 13 to 19% by 
> > removing the cooling flaps. 
> Knowing the type of "testing" Gene Berg typically used, I can just 
> about guarantee that those numbers hold no significance. They were 
> probably just pulled out of someone's.......... 
> ***************************************************** 
> ***************************************************** 
> I know Berg is right for rings and cylinders. Cold causes friction 
> numbers to rise and heat makes it float ; like a hot drill bit 
> or hot brakes =  less friction to stop or cut. 

I was referring mainly to Berg's numbers of "13% to 19%" because I can just 
about bet my life he didn't do the kind of testing the automotive studies you 
read did :-) 

In the next paragraph or so, it was listed what Berg said that cold engines do, 
and of those I said that this exact problem - ring and cylinder wear - is the 
only one that both exists and is helped by the thermostat.  The other one that 
exists is bearing wear due to cold/non-existant oil, but my point was that the 
thermostat didn't help this - the pressure relief valve did.  Even the VW 
repair manuals tout the pressure relief valves as being designed specifically 
to both regulate oil pressure and temperature (take a look, for example, in the 
BIG Bentley for 1963-67 buses). 

> This did not mention bearing , valves, 
> heads, metal alloys, expansion coeficients thirdimensional nutrino 
> phase shifts etc..... It only mentioned ringsand cylinders. 

But did it mention the top quark interaction with the discombobulating 
sublimation of the anti-magnetic field?  That's important, too... :-) 

One thing on thermal expansion: it is important in regard to cylinders and 
rings.  The less of a clearance you can have between the pistons and cylinders 
(to a degree, of course), the less wear the cylinders and rings have on them.  
When cold, there is more clearance until the piston warms up and expands... 

And, there's one other piece to the equation: how long does it really take the 
aircooled cylinders to warm up?  Air is far less conductive than water.  A rule 
of thumb to show it is that it takes approx. 26 times longer to get hypothermia 
from wind as it does from water.  Cold water surrounding a cylinder will keep 
it cold MUCH more efficiently than cold air will, perhaps by a factor similar 
to 26 to 1 (obviously not the same... but the general idea is there).  On a 50F 
day, you might putt around in a watercooled car for a long time (perhaps even 
the whole day) before the thermostat opens fully, and that's with a stock-sized 
radiator.  However, I've done this with a T1 VW and watched the thermostat 
expand fully well within one minute with the car just sitting in the driveway - 
I didn't even drive it and it was fully warmed up just idling for less than one 

All other things equal, is the stock thermostatic control system on the VW 
useful?  Sure.  By how much?  That's the debatable part.  And, are all other 
things equal?  To many, sure.  But, to some, perhaps not.  For example, if I 
have a stock engine with a stock cooling system, then there really isn't much 
of a reason to bolt a couple more bolts and put the system in (unless, of 
course, you have had bad luck with the bellows going bad and ruining a pushrod 
tube on a brand new longblock... but I digress :-).  But, if you're building 
some other kind of engine with some other kind of cooling system that won't be 
driven in arctic temperatures, then it gets into the gray area again... 

> This was caused by friction coefficient 
> values are higher when cold just like drilling steel on a drill press or 
> putting brakes on when cold. When brakes and the drill bit scenario 
> get hot , the drill bit will not cut and the brake will not brake any 
> longer ; they float on a cushion of heat energy. 

Yes and no... part of the equation is different coefficients of friction.  Part 
of it is also lubrication (for the piston on the cylinder, obviously not really 
for the top two rings).  And, yet another part is the clearance bit I spoke of 
earlier.  And, on the coefficient of friction, it's not as easy as cold=lots 
and hot=less - it depends on the materials.  For example, with traditional 
asbestos brake pads, they grab when "cold" and fade when "hot."  But, with 
semi-metallic or metallic brake pads (common in racing applications), they do 
NOT grab when cold.  In fact, you must heat them up to grab.  And, once you do, 
they grab like crazy and do not fade.  Tires on asphalt works the same way...  
But for iron-based rings on cast iron cylinders (i.e. stock T1 or T4), the 
drill bit on steel scenario does make quite a bit of sense... 

> After 50,000 miles, my engine has NO detectable cylinder ridges, 
> crosshatch still shows al the way up and rings are nice , piston 
> machining virtually unscratched. 

I recently took apart a T1 engine for my brother.  After probably 30k or so, 
there still was cross-hatching on the cylinder walls as well.  In fact, the 
only problem with the pistons and cylinders was the deep gouges made by the 
remains of a disintegrated #1 rod bearing (a.k.a. the reason it came apart in 
the first place :-).  FWIW, the engine didn't have a thermostat or flaps on it 
when I took it apart, but by the time I pushed it back in the '66 bus it did 

> I will reuse my rings and put in a gapless second ring on each 
> cylinder. 

Did you remove the pistons from the cylinders, or just take the wrist pin out 
with the piston at BTDC and leave the piston/ring/cylinder assemblies together? 
 If not, you may consider getting a new set - they're cheap. 

I've never had any personal experience with Total Seal rings, but a couple 
engine builders with which I've spoken have had bad luck with trying to get 
them to seat very well.  I don't have any more details than that, so take it 
only for what it's worth. 

> If it were not for the stripped cam gear , the engine would still 
> be zooming along. 

If not for my younger brother neglecting to pull the dipstick out once and 
awhile, his engine would have been fine, too. <sigh>  I think he learned his 
lesson... :-) 

Take care, 

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