So you think you know Porsches, eh? Then figure this out!

It was a Customer from the Southland- actually the East Southland, so far from LA that things were almost sane.

The Customer had a 1961 356B Coupe with a beefed-up 356C Engine that overheated when trying to pull the Steepest Grade in North America--from Sea Level to almost 7000 feet in only a handful of miles.
But the poor 356 would always overheat going up the hill, and the guy had to stop three times each time he tried the climb.

So, the Customer wisely brought the car up to the Maestro for a Million Mile Overhaul of both the Engine and the Transmission.

The Maestro fired it up. It started very quickly with 12 Volts on a 6 volt starter.

Then he eyeballed the oil pressure gauge--it was
idling at about 30 psi.

A tad low. He revved it up--the gauge went up nearly to 80 psi.

He let the engine idle again. Oil pressure went back down to 30 psi. That's interesting. With 80 psi at 3000 psi you'd expect 40-50 psi at idle. Not 30. Oh well.

The Maestro drove the 356 around the block to check it out. It was nothing terribly exciting. A little rough. Not a lot of Power. And a really sh*tty gas pedal "feel" that 90.356% of 356's have these days. The Cause?
Underneath the grime, rust and old candy and Trojan wrappers, inside the front Driver's wooden kickboards exists a "Bell crank" that takes your forward motion of the gas pedal, and transforms it over to the cable that operates the carburetors (eventually).

Anyhow, the owner dropped the ailing 365 off at the Maestro's Shop and left for Europe for a month on a business trip. Time for the Power Train Tiger Team to remove the Engine & Transmission for Transformation.

BAM! They were out.

The Maestro took the engine apart, and found not a bad overhaul actually--an increasingly rare event in this day and age.

The engine had an NPR Big bore Kit, with several thin (0.25mm) shims under the Cylinders to lower the compression, a wise move for Longevity.

It had a replacement wide lobe Ro 200.5 cam with several pits in the tops of the lobes. "AHA! That I can beat," thought the Maestro.

And when the Maestro removed the Fan Shroud and eyeballed the Oil Cooler, AHA! There it was--the outside of the cooler was almost completely blocked with dirt and crud--blocking a whole lot of he airflow
both through itself and to the #3 #4 cylinders. (As was shown by the deposits on the underside of the head of the Pistons- the hotter and longer the pistons run, the more crud forms from decomposing oil on the underside of the piston top.)

The 3/4 side had a good coat of brown deposits. The #1/#2 side had almost no deposits, brown or otherwise. Evidence of somewhat hotter conditions on the 3/4 side from the blocked cooler. Q.E.D.

Interesting Thing about oil coolers with a lot of Crud on the outside--they're really heavy, thanks to--Yep--all that crud on the outside, filling up and blocking the air flow passages between the blades.

All that extra weight makes for interesting Oil Cooler
vibration modes too.

But the next day when the Maestro went to clean the cooler in the Safety Kleen tank after letting it soak in the Glup overnight, he got a Big Surprise.

And he got Sprayed too.

No, that's sprayed, wise guy. Not Spayed.

The Safety Kleen tank has a pretty decent solvent pump and a tube to attach to the oil cooler inlet/outlet lines to flush the cooler of anything remaining inside.

When the Maestro stuck the tube to the oil cooler, the pump went to Max Pressure and sprayed solvent out all over. And all over the Maestro.

The Maestro tried again. And got sprayed again.

But nothing came out of the other oil cooler hole!

So he tried the other oil cooler hole. And got sprayed yet again!

He tried everything- but the solvent wouldn't go through the Oil Cooler!

And WHY was that???

Because the Oil Cooler was completely blocked somewhere up inside. And I mean BLOCKED!- Constipated! With no X-Lax.

So, I ask you Gentle Reader, if the Oil Cooler was completely blocked so that no oil could get through it, how long would an engine survive???

If the Maestro had to guess he'd say about 20,000 miles.

So, how did it survive that long with a completely blocked oil cooler through which no oil would flow???

Think about it. Look at the oiling diagram. If the Oil Cooler is blocked, the oil pressure builds up enough to push down the Oil Bypass plunger in the Third Piece of the Case, the first thing in line from the Oil Pump outlet.

This diverts oil directly to the Main Bearings, which feeds the Rods, and the Cam and the Cam Followers and then the Rockers so at least they get oil.

But the oil doesn't ever get to the oil cooler! So it doesn't get cooled. So, guess what- the engine overheats! Especially going up The Hill!

Amazingly, the engine made it the 500 miles from the South East Land to the Maestro's- but of course it was in February and cool, which helped immensely.

Somehow, going over the Mountains outside of LA on a hot day in July might not be such an easy trip.

The Maestro was Absolutely Amazed! For inside the Oil Cooler are several cooling "blades", each divide up into separate passageways. So, how do you block ALL THOSE PASSAGEWAYS!
 

The only thing the Maestro could think of was that some worker had soldered a blocking dam at the top of the Oil Cooler. That would completely block the flow from the "up" to the "down" side and completely block the flow.

The only way to find out what's happening was to either X-Ray or section the cooler.

Sectioning would much more exciting. Dissection of a Cooler's Coolerary Occlusion.

Stay tuned for Autopsy Pictures.

Tax Day, 1999...

...an appropriate time for Sectioning. Sectioning something other than you, That having been done that very day to your wallet by the Federal & State Government.

The Maestro took the Overweight & Constipated oil cooler over to Jay for an appointment with the Sectioning Saw.

Five Easy Pieces later, the drawn & quartered (+1) Cooler was laid out on the Autopsy table, before the Porsche gods and everybody, for them all to see. The Evidence before their very eyes.

An what did they see?

Place your Vote here:

The Choices are:

1. A. Pieces of Rod Bearings blocking passageways
    B. Pieces of Main Bearings blocking passageways

2. Entire body of or Bits of Bugs/Insects inside:
   
    A. Cocoons
    B. Mud Wasps
    C. Other- Specify:

3. A. Rat poo-poos.
    B. Other species poo-poos- Specify:

4. Something else: Specify _________________

Tax Day, 1999...

...the drawn & quartered Oil Cooler, sectioned into Five Easy Pieces was laid out on the Autopsy table, before the Porsche gods and everybody, for all to see.

And what did they all see?

Some things most interesting. The Oil Cooler "Blades" that take the oil through the cooler are internally baffled--in staggered rows to provide both mixing of the oil (to prevent stratification) and and even flow distribution throughout the "blade". Very clever design! Many Kudos from the Maestro.

The cross sections of the Cooler looked like a big block of Silver- or a Hamburg apartment building, with Sunshades and Balconies.

There was the "lattice work" the Accordion- shaped convoluted sheet metal between the blades for the air flow--the Sunshades.

Then there were the actual oil passageways--the "blades" with the
internal baffles that looked like "Balconies".

And the first three Sections of the Oil Cooler--from the Base up
were "clean"--with no defects and fully open passageways.

Ah, but the fourth section of the Cooler--up near the top where it would
be if installed on an engine--she weigh like-a- pig!

And when the Maestro eyeballed the oil passageways he saw solder entirely filling the "Top" few centimeters of the Fourth Section of Cooler.

And the Fifth Section- where the oil flow turns at the "Top" and goes out and down the other three blades-- the "Outlet Plenum" if you prefer--was completely filled with Solder!

Hence, COMPLETELY blocking off ALL oil flow through the Cooler!

And there ain't nooooooo way that even 135+ psi air pressure is a-gonna blast through a half-inch of Solid Solder!

The Fifth Section at least had a Use- it could still be used for Deep Sea Fishing- for it was nearly a solid lead weight! And great for ocean-fishing!

In fact, all this Lead Weight made this Oil Cooler weigh much more than a "Regular oil Cooler:

Oh, and How much do "Regular" Oil Coolers weigh, I hear you ask?

That's the next part of the Quiz.

Well, thanks to Brad Ripley of NLA and the Maestro's Triple Beam Balance Bathroom Scale, we have a Table of Oil Cooler Weights:

• The 356A BEHR Cooler made of light allow weighs barely 2 pounds.
• The Stock Late Model 8mm stud Cooler as well as the late 912 Oil Cooler both weigh some 1,450 grams, or about three pounds
• The "funky" Oil Cooler sold for a while in the early '90's by the Dealers weighed in at 962 grams or about 2 Pounds.
• The new all Aluminum Oil Cooler from NLA weighs some 789 Grams, or about a pound and a half.

Care to guess what THIS Oil Cooler weighed?

The oil cooler clogged with Solder tipped the scales as a Heavyweight--weighing in at 2149 grams or almost Five Pounds!

Almost two pounds of Solid Solder plugging up the Werks, if you know what I mean.

Guess they musta been hanging the cooler by its studs down into a Solder Bath to solder the blades to the "top" plenum when something went wrong, went wrong, went wrong... and the solder sucked itself inside, filled up the lower plenum, and guaranteed that no oil shall pass therethrough, henceforth. Forevermore. Till Time Infinity.

So, I hear you cry, just where was the "Quality Control" at the "LR" Oil Cooler Factory that day in October, 1986? Did they just get back from a Strike? Or were about to go on one? Did Herr Numnutz do this on
purpose? Or was it entirely accidental?

Sure, they probably pressure-tested the Coolers to see if they leaked. Maybe. And this one sure wouldn't leak!
But did they flow test them?

"Flow Test"--like, you know--FLOW something through it--like cleaning fluid, say, to be sure you

A. got most all the crud/debris out and

B. Had Fluid FLOWING through the Cooler!

For sure, you'd think they'd flow test it!

Guess you'd be WRONG!!! For sure.

Q.E.D.

So, add yet another Rule, nay, a Truism to 356/912 Life in the next Millennium, since Murphy will Rule there like he does here:
 

Even if it be new it could still be plugged! An no one, not even the Factory, would know for sure!

But you sure would, if it applied to you Personally. On your Engine! Which it did to the Maestro's Customer!

And beware those Oil Coolers that Weigh-a like-a PIG! Or a 5-pound sack of Sugar. Not only are Overweight Oil Coolers a big, mean Vibration Machine to your engine, they can be a Constipated Turkey too!

So too, Gentle 356'ers, note the other lesson here- ifin you're in good with the Porsche gods, you don't even need an Oil Cooler on your 356!!!

Most of the time.

You can even drive Half the Length of California, in one day, at Freeway Speeds with no oil cooler--and make it without Overheating.*
By actual Demonstration.

(*= On a cool day in February.)

But you still gotta stop several times to let the engine cool down when going up the Steepest Grade in the Continental USA.

That's why you need that oil cooler- for The Extreme Conditions--like Cruising down the Autobahn (or I-5) at 100+ mph on an 100+F degree day.

Ifin you Produce more Horsepower- such as occurs when going up the USA's Steepest Grade- you gotta produce more "Waste Heat" too. Heat that must be
rejected to the Environment somewhere, somehow. (Look, I don't make The Rules--that's just the way Thermodynamics works. I know it's not Fair, but
Thermo doesn't care. You just gotta live with it.)

That somewhere where a lot of Waste Heat is Rejected is, naturally, the oil Cooler. That's when you need it- when the Going gets Tough.

And if you don't have that Cooler when you need it, you either ignore the Temperature Gauge when it starts to go into the Red Zone, and end up stopped permanently by the side of the road. Or you stop Temporarily by
the side of the road to let the engine cool down. Which would you choose?

High Speed. Hot day. Blocked Oil Cooler. Go-um up steep hill. Engine Overheat Heap Bad. Go BOOM!

So, I ask you--how did this guy go some 20,000 miles with no oil cooler?

By the Grace of the Porsche gods--that's how--the Owner was Blessed. He also took care of his car too- and drove it. (Stopped it too, when necessary--before it got too hot. The Porsche gods like that a lot. It shows
Concern, Prudence, and Caring.)

Now, how far do you think you'd get with a Blocked Oil Cooler?

A Hundred Thousand miles? (Right--Good Luck, dreamer!) Ten Thousand Miles? Hey, he did! A Thousand miles? A hundred miles? Ten miles?

The Maestro knows how far he'd get - just about outa the driveway!

No--even worse--stuck in Death Valley with an overheated, dead, blown engine, and nor any drop of radiator water to drink!

That would be the Maestro's luck!

Them the gods love, they Chastise.

Keep the 356 Faith
Maestro

P.S. As a good PhD Thesis warmup, describe the effects on Oil Flow & Pressure in a 356/912 Porsche engine when the Oil Cooler passageway is, say,
completely plugged. Predict Hot Idle and Hot 3000 rpm Oil Pressure Values, and expected Life.

Keep the 356 Faith