THE MAESTRO'S SEPTEMBER QUIZ

The Maestro doesn't like doing "just" a "Top End Job" on an engine.

Ifin you DO "just" a "Top End", as surely as Night Follows Day, something will go wrong, go wrong, go wrong with the LOWER end. And when it does, clearly, it's YOUR fault the Bottom End Failed. Even when it isn't!

The Maestro would rather do the Whole Thing and be blamed for it. So, he doesn't like to do Top End Jobs...unless he starts to feel overconfident, and maybe it would fit in 'tween the other Complete Overhauls he has going on.

(Note that this is a Violation of one of the Maestro's Strongest Rules. And needless to say, when he violates his own Rules, the Maestro usually gets screwed.)

And so it was when a poor 1968 912 Owner (is there any other kind?) wondered into the Shop one day, in seek of a Cure for his steed's Terrible Disease.

Said steed was wheezing badly and blowing Bluish-White smoke rings out of the tail pipe. And when the Maestro took off the Screw On Cap of the Oil Breather Can, more White smoke a-plenty poured out from Inside! "What's the Problem, Maestro?"

And that, of course, is Part 1 of the September Quiz.

What's the Problem?

"Well, ifin I were a betting man (and I am), I'd bet that you have a Piston Problem. Most likely a broken ring or a Ring Eating Monster that's eaten through the piston. Either way, you're gonna have to take it apart."

The guy wasn't happy with that Diagnosis, but at least he was Prepared. He had bought one of the new Millennium Big Bore kits- the ones that were almost an exact copy of the old NPR sets.

"Can you just take it apart and put these in?" he wished hopefully.

And the Maestro gave him the Song & Dance with Four Part Harmony about how doing just a Top End Job wasn't a good idea...

But the guy wouldn't buy it. "Will you do a Top End Job or not?"

"Not" shouda been the answer.

But the Maestro, having worked off most all the Summer Rush in an Engine Building Orgy when Mrs. Maestro was out of town, figured he could fit a Quickie Top End Job in easily between the ongoing projects.

And so he agreed. Thilly boy.

The guy removed the engine himself to save a few bucks and brought it down to the Maestro's Shop.

The Maestro's first glance landed on the Lifting Lug area of the Case- between the First and Second Perimeter Bolt 'tween the Flywheel and the Fan Shroud.

And there it was! There WAS Lifting Lug between the First And Second Perimeter Bolts, on the Right Hand Case Half (the nut side). And what did this Mean?

That's Part 2.

The Lifting Lug was on the Wrong Side of the Case! It's always on the LEFT Hand Case Half, on Bolt HEAD Side! Since the Lifting Lug was put back IN THE WRONG PLACE, this is Proof that the Engine had been overhauled before, (90+% chance) and probably none too well as they put things back in the WRONG PLACE! Which is what the Maestro had expected.

The Maestro and Andrew tore the engine down, and found Heads with badly worn out Valves, Guides and Springs. And with 356C NON-Sodium filled exhaust valves where Sodium-Filled ones shoulda have been. Yep, the Cheap Fix was in on this one!

And sho' 'nough, the #3 Piston had an End-Stage "Ring Eating Monster" that had eaten through the side of the Piston.

Once the Pistons were removed, the Maestro noticed something Interesting- the #3 Connecting Rod HUNG in mid-air, horizontally, defying Gravity. Why was that? WHY did the 3 Rod hang horizontally? Yep. That's the Next Part. Why did 3 Rod Hang Horizontally? From the friction from all those Powdered Piston Pieces! The Powdered Piston Pieces from the HOLE in the Piston! Of course!

And yet Another good reason to overhaul the Engine Completely.

But when the Maestro mentioned the Horizontal Rod to the Owner, the Owner asked if the Rod could be removed and the Bearings replaced without splitting the Case.

Yes, admitted the Maestro, but we're starting to talk Mickey Mouse here. That crud isn't just on that one Rod Bearing- it's throughout the Engine! Which is why I recommend we split the Case and do it Right.

"No, NO, cried the 912 Owner. I just can't afford that right now."

"But said the Maestro I thought you were in a startup dot.com company?" "I am." said he. "But it's BEFORE the IPO, and it's draining me dry. That's why I have no money for the 912."

Sigh, thought the Maestro. Why do I ALWAYS get them BEFORE the IPO? Rather than afterwards when they're Flush with bucks?

That's a Question the Porsche gods could easily answer- "Because we Love you so, we must CHASTISE you so too. And so they do.

The guy wanted a Clutch Job too, and the Maestro was about to remove the Flywheel.

Before he did, as he always does, he checked the End Play Adjustment.

Twelve Thousandth of an inch, (0.012").

Not too good an End Play, since 0.004-0.006 is what's recommended. (And the Maestro likes .0055".)

And when the Maestro pulled the Flywheel off, he found a pretty thick End Play Shim already installed, about 0.038".

So, to adjust the End Play back into the Ball Park, the Maestro would have to use his THICKEST shim- 0.045". And except for Super-90's and they're different- Porsche don't make 'em any thicker.

The Maestro got out the Thickest shim he had, installed it and Torqued the Flywheel back down (with the soft iron gasket in place, of course).

He attached the Dial Indicator and Viola, the End Pay was:

Twelve Thousandths of an inch, (0.012").

The End Play hadn't changed- even with a 0.007" thicker shin!

How Can This Be? I hear you Cry.

It be because the Flywheel Main Bearing be a-movin' in the Case!

A Flywheel Main Bearing has an Outside Diameter about 0.002" BIGGER than the Case Bore. This is so the 0.002" crush of the Case on the Bearing will hold the Bearing tightly in its grasp.

But when a Case gets more than .002" too "Big" from the stresses of 6500 rpm shifts, the Flywheel Main loses its "Crush" in the Case, and is free to move. Every time you put the clutch "down", the Flywheel whacks into the Flywheel Main Bearing and beats both the Bearing and the Case.

Eventually the 2mm thick Thrust Surface of the Flywheel Main Bearing gets worn down to razor thinness and/or breaks off. That silly millimeter or two increase in End Play causes Spark Timing Variations you won't believe! And oil leaks that bring smiles to the CEO's of ChevronExxon.

Now the Maestro knew this engine had been overhauled before- the missing Lifting Lug was clear proof of that.

What probably happened was that the Case was too big (thanks to the Previous Owner revving the BeJesus out of it before he sold it to the current owner with the "holed" piston). The PO, like the current owner, was Cheap and did a Cheap Fix. In fact the Case shoulda been Align Bored Last Time!

But the Cost of an Align Bore and the much more expensive Align Bore Bearings broke the PO's Budget.

Now, the NEXT owner down the line was suffering the fierce financial effects. For now it MUST be Align Bored, and maybe a "Thrust Cut" Repair too.

The Maestro figured- "Well now, looks like the Top End Job has turned into a Complete Overhaul, which is what I wanted to do anyway."

Thank you again Porsche gods. God, you're good to me.

The Maestro, happy as a clam, waltzed over to the phone to give the guy the Good News- that now there was NO Choice- the Engine would have to undergo a Full MaestroMassage.

He confidently dialed the Number.

The guy answered.

And the Maestro told him the Story of how he went to adjust the end play from the .012" it had been down to Something Reasonable and how when he stuck in the Thickest Possible Factory Shim, the End play was STILL at .012"!

And how he had then eyeballed the edge of the Flywheel Main Bearing by looking down through the #1/#3 Cylinder hole, as he pried the Flywheel and front Pulley back and forth.

And how he could then easily see the Flywheel Main Bearing MOVING in the Case! And how it AIN'T SUPPOSED TO MOVE!

And how he had already calculate the cost of a MaestroMassage, and when the Maestro read the Most Modest Number, the guy said:

"Oh, My God! I can't possibly Afford THAT!"

With such emphasis that the Maestro almost believed him. "But it's only a little more than the Top End Job we were gonna do." "Oh, but there's NO WAY I can afford that."

"So, what are my Options?"

"Options? thought the Maestro. "You don't have NO Steenkin' Options! You gotta take it apart and FIX it."

But instead he said, jokingly-

"Well, you COULD just Mickey-Mouse it back together and SELL IT," said the Maestro, thinking, watch out Jay Leno- that was a Hilarious joke.

"That's what I might have to do," said the guy.

"Uh, I was joking." said the Maestro. "You really gotta take it apart and fix it Right. Or you'll be doing it OVER again pretty soon. Unless you sell the car."

"I might do just that!" said the guy.

"Well, why don't you think about it," suggested the Maestro.

So what do YOU think will happen. Will the Maestro be bamboozled into doing a half-fast "quickie" fix, in Violation off all that he thinks is Right?

Or will he offer to rebuild it fully, and have the guy pay in Founder Shares?

Now, that's a Plan! Keep the 356 Faith Maestro P.S.

It was a Momentous Saturday. The Magnificent Creation, the Blue Beast was outside the Maestro's Shop, along with the Near Virgin in Off White.

Next to it, almost the same color, was a Pristine 1964 356C, a REAL Original Owner California Car. So Original it belongs in the Smithsonian.

Soon to come was a Buyer from San Fran who had searched fruitlessly throughout the Internet for a REAL, Original California Car 356.

Soon the two were to meet and make a deal.

Already arrived was a man and his son from LA who came to pick up the MaestroMassaged Power Train for their 1959 Convertible "D".

The Maestro was glowing happily from the check in his pocket. The gods were smiling upon him. And when they do, you'd better bask in the glow. It doesn't last long.

The Maestro decided that this might be a good time to call, one more time, the 1968 912 Owner about the loose Flywheel Main Bearing.

Amazingly, the guy answered the phone (a Rare Event in the Silicon Valley- usually the guy's always out!)

The Maestro said:

"Y'know if you're gonna be rich in a couple of months, how about we just put the engine on the Shelf until then." "If you stick it together the way it is, you'll be taking it apart again soon. And then the Very Nice Rebuilt Heads and New Pistons won't be new anymore and may not seal the Second Time Around with redoing them again."

The was a pause on the line.

The Maestro had about given up Hope, when the guy cam back on.

"Y'know. That's sounds like a better idea! I could live without the car for a couple of months, and then have a GOOD car!" "THAT'S right, agreed the Maestro. And the desire to get your car back On The Road will give you INCENTIVE to do well with the IPO. I'll strip it down today and tell you what I found."

"Go to it," said the Owner.

About that same time, the Buyer and Seller outside were striking up a Deal.

What a Great Saturday!

After the Deal was done, and the California Car got to stay in California, the Maestro went out to the 1968 912 and completed the Disassembly.

And there were more Signs of Incompetence. The Third Piece of a 912 take Seven 8mm nuts that are 12mm ATF (Across The Flats). This one had 13mm ATF nuts on the Third Piece, and the 12mm ones scattered throughout random Case Perimeter Bolts. With one 12mm and one 13mm ATF nut on each of the two Cam Plug Studs. Geez.

And the Acorn Nut Washers! 356's after 1960 and all 912's have special, Beveled HARD Case Washers that fit under the 6 Case Acorn Nuts. (The Bevel compresses an "O" ring around the Case Stud and prevents oil leaks.)

They apparently got lost somewhere along the line, and various types of random washers used instead.

Gobble, Gobble.

The Maestro got dropped the Drain Plate to find a buncha "hair" on the Magnet and more than a little "Debris" around the screen.

Ever the More Reason to take it apart!

The Maestro took off the Third Piece and split the Main Case Halves.

And out popped the still-Standard 912 Crank. With nice, never reconditioned Rods, a decent cam and good Cam Followers.

But when he popped the Crank outa the Case he fond something else Interesting.

There was a lot of Red Stuff in the Bearing Saddles.

So, what was this Red Stuff and why was it there?

Yep, it was RED LOKTITE! Used by the previous rebuilder in a vain attempt to hold in too-loose Bearings.

Which didn't work- the FWM was a-moving' in the Case!

And the Thrust Surface was worn to almost razor thinness! It wouldn't have lasted much longer!

The Maestro eyeballed the backs of the Middle Mains.

"OD, +.010" said the Back of the Bearings.

Great, thought the Maestro. The Case already IS First Over! Either the clowns didn't bore it right or it suffered tremendous abuse, 'cause now it'll probably have to go to SECOND oversize!

And Second Oversize Align Bore 912 Main Bearings are like Hen's Teeth!

Geez.

But to check the Case, the Maestro first had to clean it.

And it'll take 'till Tuesday to do that.

Meanwhile, What's your guess for the Case Bore. Case Bore. The Choices: A. Within 0.001" of Standard B. Within 0.001" of First Over C. First Over and from +0.001 to +0.005" too big. D. First Over and from +0.005 to +0.009" too big. E. Within 0.001 of Second Over F. More that +0.001" beyond Second Over

Hey, the Maestro doesn't know which one it'll be. You have as much a chance as anyone else!

Let's see if the Delphi Technique works.

Keep the 356 Faith

Maestro
 

 

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