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What killed this LT1?

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Old Dec 1, 2004 | 03:25 PM
  #1  
Gripenfelter's Avatar
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What killed this LT1?

My friend's stroker LT1 just went south on him. It had maybe 10,000 miles on the new motor.

When we tore open the motor we found:

8 forged pistons with scorched skirts on the side facing the cam.

1 spun rod bearing. King bearings used.

He has a Melling High volume oil pump and a stock size pan.

Why did the bearing spin? Why did the pistons scorch?

He did a burnout and raced and saw a drop in oil pressure immediately afterwards.

Last edited by Gripenfelter; Dec 1, 2004 at 03:29 PM.
Old Dec 1, 2004 | 03:54 PM
  #2  
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Re: What killed this LT1?

Oilpump sucking air. What viscosity oil was he running?
Old Dec 1, 2004 | 05:54 PM
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Re: What killed this LT1?

10w40?
Old Dec 1, 2004 | 06:44 PM
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Re: What killed this LT1?

what rpm did the motor see during the run/burnout? i would guess lack of oil somewhere, but i need more info on rpm. did the pick up come off?
Old Dec 1, 2004 | 06:50 PM
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Re: What killed this LT1?

i know this sounds really stupid, but did you install the oil pump pickup deep enough into the pan?
Old Dec 1, 2004 | 07:57 PM
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Re: What killed this LT1?

[QUOTE] QUOTE]


Was there any overheating , or hight engine temps. With the bearing spun and scorched skirts, it sounds like something burned maybe because of oil starvation, or over heating.


What color are the bad bearing/s .... How do they look?

Last edited by Rpm280; Dec 1, 2004 at 08:04 PM.
Old Dec 1, 2004 | 11:12 PM
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Re: What killed this LT1?

Was there any sort of windage tray on the studs or in the pan?

What did the other rod bearing on that crank throw look like?

Bret
Old Dec 2, 2004 | 01:04 AM
  #8  
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Re: What killed this LT1?

durring a burn out?

may sound REALLY stupid but... was it running REALLY rich? was there an exhuast leak?
Old Dec 2, 2004 | 07:41 AM
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Re: What killed this LT1?

Strange that it burned all the pistons on the cam side. Did you happen to notice where the ring gaps were aligned on the pistons?
I would send the oil out for analysis.
Old Dec 2, 2004 | 09:24 AM
  #10  
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Re: What killed this LT1?

There was no problem with the pickup.
Stock oil pan.
No oil scraper.
Rod showed burns as well where the bearing spun.

He says the car has never been overheated. He was revving to 6500rpm during his run. 6000rpm for the burnout.

My guess is the same as yours that he starved the engine of oil. I just wanted someone else to reach the same conclusion as me.

Would a thinner oil or synthetic have saved his motor seeing as how he was running 10W40 dino oil?
Old Dec 2, 2004 | 10:35 AM
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Re: What killed this LT1?

I've always thought it was recommended that you not run a stock pan with a high volume oil pump, for exactly this reason, oil starvation. Which bearing spun?
Old Dec 2, 2004 | 11:05 AM
  #12  
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Re: What killed this LT1?

Originally Posted by Gripenfelter
There was no problem with the pickup.
Stock oil pan.
No oil scraper.
Rod showed burns as well where the bearing spun.
You didn't have that stock plate/windage tray in there even?

I'm betting that's the problem, longer stroke with that and all that dam windage and no way to keep the oil in the bottom of the pan picked all the oil up away from the pickup during the burnout and boom there goes the bearing.

Get a Milodon Tray or a Canton Pan, something anything to keep that puppy from picking up all the oil in the pan and starving the pump.

Bret

Last edited by SStrokerAce; Dec 2, 2004 at 11:07 PM.
Old Dec 2, 2004 | 01:02 PM
  #13  
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Re: What killed this LT1?

Originally Posted by Z28SORR
I've always thought it was recommended that you not run a stock pan with a high volume oil pump, for exactly this reason, oil starvation. Which bearing spun?
Rod bearing #6.

Thanx guys I'll pass on the info. He's ordering a Canton pan as we speak.
Old Dec 2, 2004 | 01:14 PM
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Re: What killed this LT1?

hes prolly gunna need alot more than that lol

i also heard that u dont run a high volume oil pump with a stock pan...
Old Dec 2, 2004 | 03:19 PM
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Re: What killed this LT1?

Originally Posted by Seal
i also heard that u dont run a high volume oil pump with a stock pan...

Hmmmmm....I did not know this. I have been running a Melling HV/HP pump with a stock pan for three years now, spinning the motor to 6500 and haven't had a problem.



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