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THE MAESTRO'S FEBRUARY QUIZ
Hey- what can I say? Impossibly Rare Porsche problem keep coming to him, like little lost lambs, so the Maestro keeps writing Stories about 'em! Quizzes too.
Ringggggggg,.... Ringgggggg... goes the phone.
"Maestro here", comes the reply. "Hi there Maestro", says the VOP. "I've got a problem that maybe only you can solve."
"Bless you, my son. Now what appears to be the Problem?" "Well, I rebuilt my 356B engine because the oil cooler stand developed a crack and, of course, a major oil leak. So I took the engine apart and sent the Case to a machine shop near a Lake, where they weld-repaired the oil cooler stand area." "Yes," said the Maestro. And did that fix the leak at the oil cooler stand?" "Actually- yes," said the VOP. "The Oil Cooler Stand didn't leak- but oil just POURED out of the engine from the FLYWHEEL area!" "Oh, that's Interesting," said the Maestro. "You had a Flywheel Seal Leak, eh?"
"I'm not sure", said the VOP. "When I pulled the Flywheel back off, I found oil all over the side of the Flywheel that faces the Case." "Hummh," though the Maestro. "That's the Seal Side all right. Did you check the Clutch side of the Flywheel to see if there was any oil coming through the Flywheel Dowel Pin holes, out under the Flywheel Nut to form 8 radial streams of oil radiating out to the Clutch? (Oh, so THAT's why there are three holes drilled into the Flywheel on the inside edge, just before the Clutch Disk surface starts. The holes channel oil from leaking (or missing) Soft Iron Gaskets or other defect(s) that allow oil to come through the dowel pins under the Flywheel nut and out the back of the Flywheel so it won't get on the Clutch Disk. Boy, you done lern something every day!)
"Nope, said the VOP, breaking into the Maestro's loosely connected thoughts. "The clutch side of the Flywheel had NO oil on it at all- in fact the Clutch was as dry as a bone. The Big Oil Leak was on the "Flywheel Seal" side of the Flywheel. And boy- it was leaking like a sieve. But, what's weird is that for THIRTY YEARS this Engine NEVER had a leak like that. Have you ever have anything like that??" Well, have you? And what is it from? That's Part 1 of the Quiz.
"Oh, yessssss", said the Maestro. "There was an owner-built engine that had a "Seal Leak" that several separate seals failed to fix. (The attempted seal "fixes", of course, were necessarily accompanied by Removal & Replacement of the Engine and Flywheel each and ever more frustrating time.) Finally the guy got smart and brought the Flywheel in to the Maestro. Turned out the Flywheel had been machined on the Sealing Surface to clean up the "wear" line, but had been cut so much that no seal would seal. Another flywheel solved his problem.
But this VOP's Flywheel Seal Leak wasn't about to be fixed by something so simple as a Flywheel replacement, for the same flywheel HADN'T leaked before the engine was repaired.
The Maestro told the VOP to inspect the Sealing Surface of the Flywheel for defects. It was smooth. Measure it. It was the right size. Put a new seal over the Flywheel lip and be sure the Seal seals all around. It did.
The guy had done everything right, but by Murphy, there was this Big Bad Oil Leak coming from the Flywheel Seal Area.
The Maestro suggested that maybe it wasn't REALLY a Seal Leak or was it something else- a cracked Case, a leaking Cam Plug or ...?
The guy couldn't tell, since the Flywheel is soooooo close to the Case you can't see anything important by looking between the Flywheel and the Case with the Flywheel installed.
The guy got so desperate that he became Ingenious and undertook a Noble Experiment. He found another "junker" 356B Flywheel that was absolutely no good- and machined out the center section until he had a 4" diameter Hub where the Flywheel Nut mounts and the Seal seals.
Then he attached this chopped down flywheel "center section" to the Crank as he would a Real Flywheel. With Flywheel nut and all.
Then, if he turned the engine over fast enough and built up enough oil pressure, he could SEE where the damn oil leak was coming from!
The only problem was- ifin you machine the Flywheel down to a 4" center section, how you gonna turn the engine over, Bo'? There ain't no Ring Gear Teeth there no mo', so a Starter ain't gonna work.
So, how DID he turn the Engine over anyway? That's Part 2 of the Feb 1999 Quiz! ****************************************************
Originally the Owner thought he could use his Heavy-Duty half-inch Drill with a 30mm socket attached on the Pulley, and crank it over that way.
No way, Jose- the Heavy Duty Drill couldn't budge the Porsche engine.
So he resorted to Older, but more proven means- a two-and-a-half foot Breaker bar rotated by hand. (It helps to have a "neckers' knob" from on steering wheels from the '50's and '60's to speed the process.)
Anyhow, by cranking the breaker bar around Sufficiently Fast, it is left as a Proof for the Student that the oil pump can be made to pump a significant amount of leak-checking oil, made ever the more so leak-checking by the addition of a little Fluorescent Dye from the NAPA parts store. (Hey, I told you this guy was SMART!) His assistant stood by at the front of the engine with an UltraViolet "Black" light. (Doctor: "You ever been X-rayed?" Southern Girl: "No, but Ah've been Ultraviolated.")
And sho' 'nough after about 30 seconds of Vigorous Cranking Exercise, the Assistant at the front of the engine yelled- STOP! I don't need no steekin' UV Light- there's Molasses-like stuff oozing out from... OK, so where was the Oil Oozing out from???? ****************************************************************** The Molasses-like stuff, oil, was oozing out from BETWEEN THE CASE HALVES- just above the Flywheel Main Bearing bore! "And," said the VOP. "I could stick a 0.004" feeler gauge, between the Case Halves, just above the Flywheel Main Bearing Bore.
The oil was pouring out from ABOVE the Flywheel Seal, dripping down onto the Seal- thereby cleverly incriminating it- and then onto the Flywheel for Distribution all over the place.
It wasn't a Flywheel Seal Leak at all- it was a Big Gap in the Case!
Now, WHY did the Case have such as Big Gap there? ***********************************************************************
The Maestro asked the obvious question- "So, did the welding of the Oil Cooler Stand area warp the Case?" "No, said the guy. It was my own damn fault I think."
"How so?" asked the Maestro "Because when I went to assemble the engine, I wanted to be sure that the Flywheel Main Bearing was tight in the Case, and I had read on a package of Red Loctite that it can be used for Bearing Retention. So, I put Loctite on the back of the Flywheel Main Bearing, torqued the case together lightly, let the Loctite sit and then did the final Torquing.
The Loctite apparently got pushed out from where it was on the Bearing and got between the Case Halves. Then, like any good anaerobic polymer, it polymerized there- BETWEEN the Case Halves- to rock-like consistency. A Loctite Rock. The Rock Loctite.
The Great, Red Loctite Rock.
So, when I tried to torque the case together, the solid Loctite prevented the Case Halves from coming fully together.
I measured chunks of Loctite almost .010" thick. THAT was holding the Case halves apart enough to cause the Massive Oil Leak!"
The Maestro was IM-pressed- because here was something he had SEEN before, but never done himself- for that is the Wrong Solution.
The Maestro is a Believer that ifin the Case is the Right Size and the Bearings and Crank are the right size, then the Bearings are held into the Case tightly by CRUSH! And they don't need no steenkin' Loctite!
(Yes, the Rod Nuts benefit from drop of Red Loctite, as does the Flywheel Nut, and several other things, but NOT the backs of the Bearings.)
The Maestro's SEEN Loctite used on Bearings in a few of the "Core" or exchange engines he's gotten in, but that's a Turkey "repair" that doesn't address the real problem that the CASE BORE IS TOO BIG!
So, gentle reader, the next time you're tempted to cheap out and use Loctite to hold in an otherwise too-loose Main Bearing, think again, remember this Story, and DON'T.
Keep the 356 Faith
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