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Discussion Starter · #1 ·
The engine builder and mechanic informed me that he has to tear down the new engine because he has witnessed copper shavings in the oil filter after initial break in. He pulled the engine out and removed the oil pan and one of the bearings is beat up.

The engine ran beautifully for the initial 20 min break-in and during the second 20 min break-in. He opened up the oil filter to check for shavings and there they were. He's pretty sure that a bearing is toast (thrust bearing ?) There is too much end play now in the crank (normal .006 now .025).

He suggests two reasons - one, defective bearing or two, too much push force on the crank from the tranny (t5). I have a Mcleod scattershield installed so no indexing was needed . I hope that isn't the problem. Any thoughts? Have you heard of this happening before?

Specs 331- late model 5.0 block, Comp cams roller cam, scat crank and rods, probe pistons. Distributor gear is steel and correct..

The trans bolted easily to the bellhousing and engine with no problems - no extra forcing or pushing.

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<font size=-1>[ This Message was edited by: DrStang on 5/28/06 6:45am ]</font>
 

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Did you even use the clutch? While you were breaking it in?
thrust bearing it the center bearing.
Did the builder give you a build sheet?
What was the as built end play for the crank?
You did have the rotating assembly balanced?
 

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Discussion Starter · #3 ·
On 2006-05-27 17:28, forthman wrote:
Did you even use the clutch? While you were breaking it in?
thrust bearing it the center bearing.
Did the builder give you a build sheet?
What was the as built end play for the crank?
You did have the rotating assembly balanced?
Here my best answers: As I wasn't at the break in - only the engine builder was there

1. Clutch wasn't used
2. Not sure (thrust bearing is the center bearing?)
3. No build sheet
4. I believe .006 - now its .025
5. Yes it was professionally balanced
 

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Question for you, did he show you the bearing? was it both sides or only one and which side? Makes a difference.
 

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Discussion Starter · #5 ·
On 2006-05-28 10:06, dacofa wrote:
Question for you, did he show you the bearing? was it both sides or only one and which side? Makes a difference.
Don't know yet. I can post when I find out. Why?
 

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If it is one side of the bearing, like the rear part, something is pushing the crank forward. Usually torque convertor is installed wrong, if it is automatic.

On a stick either a problem in the clutch or the front shaft of the transmission is too long, pushing on the rear of the crankshaft through the pilot bearing.

Just changing the bearing isn't a fix. It will do it again, till you fix what caused it. I doubt it is an engine problem. I'd look at clutch, trans, etc.
 

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One thing to consider. If your engine builder broke in the for 20 minutes, not once but twice, you might want to reconsider his credentials. Roller cam engines don't require the 20 minute break-in that flat tappet cams require. He may not be as good as he led you to believe.
 

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Discussion Starter · #8 ·
Update, took a look at the bearing in question, It's only the backside that is affected. Tranny output shaft is okay, proper length. But I agree something must be pushing the crank but what?

BTW it's a T5 transmission.
 

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I would still lean toward the trans. input shaft.

You need to measure, very accuratly, the length of the shaft to the beginning of the pilot bearing and with the depth of the pilot.

Does the engine have end play without the trans. installed?? Then check it with the trans. bolted up. I think you'll find that it is a tad too long and pushing the crank forward.

Further, I agree with "geronimo" about why the 20 minute break in??? And not once, but twice?? Sure it didn't cause a problem, but it shows knowledge/experience.

Good Luck, keep us informed.


<font size=-1>[ This Message was edited by: Gearhead99 on 5/30/06 4:13am ]</font>
 

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On 2006-05-29 09:15, geronimo wrote:
One thing to consider. If your engine builder broke in the for 20 minutes, not once but twice, you might want to reconsider his credentials. Roller cam engines don't require the 20 minute break-in that flat tappet cams require. He may not be as good as he led you to believe.
True but the valve springs should be run in for at least 10min.
They have a need for proper break in as well, plus it's good for the rings to see some rpm and very good for the roller lifters to see rpm.
You should never build any engine and not break it in some.
Brian
 

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I think gearhead nailed it, it is your tranny, triple check stuff like he said.
is thranny shaft or flywheel not deep enough.
 

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Discussion Starter · #13 ·
Well, we checked a few more things. The tranny shaft is within specs and doesn't bottom out inside the crank. Pilot bearing looks normal. How else could the tranny push the crank? - I'm stumped.

Aside - I'm using the new Ron Morris motor mounts and they have the motor sit higher. This also creates a significant downward rear slant to the engine - don't know if that affects anything.
 

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Id check the end play on the crank WITH the trans/clutch pressure plate assy installed. See if it still in spec.

Is it possible that the center main is dry or not with enough pressure to keep the thrust oiled??? Just a stab in the dark.

I dont know, just seems like something is shoving that thing hard up against the thrust. Is it possible someone milled the flange of the scattershield thus causing the trans assy to go deeper spec will allow? Or maybe its just out of spec for the model T5 you have????

Just some basic thoughts, although im no expert.
Good luck
Robert

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<font size=-1>[ This Message was edited by: 71hotrodpinto on 5/31/06 1:26pm ]</font>

<font size=-1>[ This Message was edited by: 71hotrodpinto on 5/31/06 1:27pm ]</font>
 

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question again, are you using a block plate and what type of bellhousing is it? If the trans is right, might be at the bellhousing.
 

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Discussion Starter · #17 ·
On 2006-06-02 00:19, dacofa wrote:
question again, are you using a block plate and what type of bellhousing is it? If the trans is right, might be at the bellhousing.
I'm using a Mcleod scattershield (bellhousing) and the accompanying block plate. This is a mass produced item, I'd hope it wouldn't be the problem.

As of right now, the machinist hasn't picked up the block for examination. Until then I'm stuck - car show season is here and I can't show the Mustang.

I'll will post as soon as details are available.
 

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Sorry to hear about the problem... that really sucks.
It does sounds like the tranny is pushing forward.
Do you have a pic of those mounts? That angle could be an issue...

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<font size=-1>[ This Message was edited by: Thordane65 on 6/2/06 10:58pm ]</font>
 

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Why are you looking at the motor mounts??? The transmission is bolted securly to the bellhousing, which is pinned and bolted to the rear of the engine.

What do the motor mounts have to do with the crankshaft forward enough to burn up the rear part of the thrust bearing??
 
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