Mike Frye

Wayne,

You said you checked the flex plate and it was forward about a half of an inch. Did you adjust it (relieve it?) or no? I'm just wondering how the starter relay or just letting it sit would allow the car to start and run properly after all that.

I don't know anything about this, I'm just asking questions to learn more.

Shark Attack

After the engine cools i guess the metal is harder and not over sized becasue of the heat. Kinda like putting your swollen foot in a shoe. I have been here... I do hope its been caught in time. The sad thing is, just to find out if the motor is salvagable cost a pretty penny.... to really tell I think it has to be pulled... So you spend 1500-2000 in labor just to find out if you need a block.... TBF SUCKs BIG MONKY *****

Gretch

A half an inch float cannot be correct........... That is ENORMOUS for end play. How did you measure this "half an inch"?

Ok, sounds like your half an inch is not end play....... I am not sure what you have measured......... movement of the clamp off the tt spline?

Bill Ball

Hey, Gretch. He found half an inch of flexplate preload. He hasn't done the endplay yet. Anxiously waiting to hear.

tomcat

Hey Wayne,

Sorry to read about the possible scenarios. Give us the word and we'll be at your house to help you out. I can open beer bottles.

Seriously, let us know.

jpitman2

IIRC limp home mode tends to produce broken shafts, due to the cyclic shock loads of only one bank running. I cant see how the limping would suddenly push the shaft and increase the end loads?
jp 83 Euro S AT 50k

Jim bailey - 928 International

Running on 4 cylinders really should NOT be called "limp home mode" since the car should NOT be driven that way and the intent was the "my car lost 1/2 it's power and runs rough but I am too stupid to quit driving so to keep it from catching on fire the car shuts off 1/2 of the injection " But it is NOT limp home ...the limp mode is a default program in the LH injection that will run the car at low speed but poorly on all 8 cylinders like when the mass air sensor fails.

FlyingDog

Let's call it "makes your nice Porsche V8 sound like an old VW while lighting your bumper cover on fire mode". Sounds about right.

Bill Ball

4 cyl mode, tripped by the ignition monitoring system, has been reported by Porsche to snap the TT at just above idle. Not the problem here.

dr bob

The real failure on thrust bearing disasters is probably the cracks in the main bearing web, if I recall Greg Brown's descriptions correctly. If the web isn't cracked and the crank isn't damaged, you --MAY-- be lucky enough to just be replacing mains. Still a chore, but less than finding another block. The endplay measurement is the tell-all. You may also want to drop the pan for a peeky inside, even if the endplay isn't way out of spec.

Owners also need to remeber thta the driveshaft isn't stretching, it's shrinking under torsional distortion. It pulls itself out of the flex plate under severe loading. When it unwinds as the loading is reduced, it pushes on the flex plate.

Maybe what we need is a flex plate with more flex available before the collar slips. Or a drive plate that resembles a clutch disk, and allows the drivshaft end to move in and out as needed. A spot of grease, a pilot bearing, a stub shaft with a sleeve? Or maybe a bigger driveshaft, tubular for min rotating inertia, one that doesn't wind up so much.

SharkSkin

IIRC the point of no return for a block is the point where the crank is grinding into the web underneath the TB, having worn away the TB entirely.

Bill Ball

If the TB spins it can crack the bock, even if not worn through and with no counterweight contact with the web. We had a case reported here last year and Greg Brown said he sees it in TBF. There was still almost a mm of bearing wall left.
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Sharky

Hey Guys,

I haven't had the time to measure the end play as of yet , but the half inch movement was the flex plate release. I picked up the tools from autozone yesterday. The dial meter is now digital. Hopefully I'll be able to get to it this weekend. I'll post the results. When I checked the flex plate before SITM there was no movement on the flex plate. I think I didn't tighten the bolt enough.

BTW, at SITM I remember having a slow almost dead crank, but it started OK on the second go around. I remember my wife asking me what's that? I'm sorry to say that I blew her off and said nothing! She always knows best.

Gretch

ouch........... x 2

wg928

CHEVY MOTOR ,big cheap horses... keep the hood shut. oops ...who said that, who needs enemies with a friend like me. After our talk today I still hope it's not as bad as it may seem.