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25psi Bliss
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Discussion Starter #1 (Edited)
Ok,
Imagine that bearing "A" is from a motor with about 60k miles with normal wear and from a different motor. What could be the cause of the substantial wear on "B", "C", "D", and "E"? What could be the possible reasons for this catastrophe in about 4000 miles. These were on a different motor?
I'm stumped ....
 

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BlackDevilSupra said:
Ok,
Imagine that bearing "A" is from a motor with about 60k miles with normal wear and from a different motor. What could be the cause of the substantial wear on "B", "C", "D", and "E"? What could be the possible reasons for this catastrophe in about 4000 miles. These were on a different motor?
I'm stumped ....
My guess would be lack of oil...
 

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BlackDevilSupra said:
Ok,
Imagine that bearing "A" is from a motor with about 60k miles with normal wear and from a different motor. What could be the cause of the substantial wear on "B", "C", "D", and "E"? What could be the possible reasons for this catastrophe in about 4000 miles. These were on a different motor?
I'm stumped ....
I can not understand what you are saying.
 

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25psi Bliss
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Discussion Starter #5
"A" was from motor #1 with about 60k miles
"BCDE" were from motor #2 with about 4000 miles.
Two different motors, two different rod bearing characteristics.


Howard.
 

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Gotcha!

I'd have to blame the problems of BCDE on:
1) Improper preparation of crank and rods at rebuild time
2) Improper oiling
 

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25psi Bliss
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Discussion Starter #7
Oh,
I almost forgot to note that the bearings were sped'ed out properly during installation via the TSRM spec's. Right smack doodle in middle of the TSRM tolerance range.

Thermactor said:
Gotcha!

I'd have to blame the problems of BCDE on:
1) Improper preparation of crank and rods at rebuild time
2) Improper oiling
 

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BlackDevilSupra said:
Oh,
I almost forgot to note that the bearings were sped'ed out properly during installation via the TSRM spec's. Right smack doodle in middle of the TSRM tolerance range.
Well.. did you have the crank and rods polished? Did you use the proper assembly lube? Did you break in the motor properly? How soon did you change the oil after first startup?
 

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hmmm...not knowing everything in the engine or the circumstances...oil starvation would be a first guess, as would have been preparation. Perhaps some of the oil galleys were plugged?
 

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bgrieger said:
hmmm...not knowing everything in the engine or the circumstances...oil starvation would be a first guess, as would have been preparation. Perhaps some of the oil galleys were plugged?
Given the low miles, I'd say that the damage was done within minutes of the time that the motor started running in the first place. I'd put the majority of the blame squarely on everything that goes under the heading of preparation.
 

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As mentioned, could be that the crank was not turned. Also, as mentioned, could've been because of poor prep. Not lubricating them during assembly. Long shot here, but faulty oil pump. Maybe?
 

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I vote for poor rebuild. Looks like some small shit tore up those bearings. Did you use assembly lube when you put it together? did you change the oil within 5 minutes of initial start-up? did you change the oil again within 100miles? If not, the break-in process will often have small metalic particles in the oil
 

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here are the details...

block was cleaned and honed. Pistons were checked by machine shop for tollerance and then checked upon assembly and new rings assembled. Rods had ARP bolts installed with the large and small ends redone. Crank was turned with oversize Clevite bearings installed. Crank was checked for thrust tollerance and bearing tollerances twice and both times came in middle of spec. Same goes for rod bearings. Head had standard 3-angle valve job and shimmed within spec. Greddy 2mm head gasket installed with ARP bolts torqued to 90 ft lbs. New Toyota oil pump was installed. LIBERAL amounts of assembly lube used!

ALL TOLLERANCES WERE IN SPEC!

Motor was started with water spewing from TB from bad seals which leaked water into intake, but motor was "supposedly" turned off immediately. Water was pooled in lower intake. Oil was supposedly changed 3 times by 3k miles. Motor was making noise around 2-4k miles.

Now go back and look at the pics B,C,D,E and make not of the wear on "E". What do you make of this now?
 

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Well, I know that alex (kingsoup) had a problem with this.. He's blown say... 4 bottom ends. What his problem was is the oil cooler was clogged and blocking flow. This was starving the engine for oil even though the oil pressure looked good.

As someone said maybe a oil clot in the system? Also what thickness of oil are you running I'm wondering if you're running a thin oil on high boost? I'd bet thats spells trouble since all the heat being created isn't being expelled.
 

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Do you know the answer and you're testing us, or are you trying to find out what went wrong? :p

My guess, water gets into the intake which causes a partial hydro-lock on the middle three cylinders, enough to shock the rod hard enough that it displaces the oil film and touches the crank metal-to-metal while they're spinning.
 

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Shocking the rods is a theory I hadn't even considered, but it could make sense as well. The bottom line is some guy (who's name I won't disclose) is trying to hold me responsible for a motor I built, but I told him "do not start it without me there!" He didn't listen and , viola, the motor is toast. When I went back to fix all the things wrong with the install, there were loose clamps EVERYWHERE and the motor was spewing all sorts of fluid from various places. (Install tip #1... tighten clamps right when you put the hoses on them and don't think you'll do it later, cause you won't!) But when I removed the upper intake, the runners were filled with water which I sopped up with paper towels. (This came from a sloppy TB shaft and old seals) The motor ran fine after the water was removed and a new TB installed. This guy's arguement is "had the motor hydrolocked it never would have ran 4k miles." But my arguement is the damage was already done and it just took 4k miles to finally wear down. Figure after 2-3k it was making noise. I have a major problem with the fact that this guy didn't listen to me in the first place and now I am being held responsible for his mistake. On top of this, all this work was done for FREE! I don't want to give my ideas or theories as I do not want to sway opinion, but the question of if oil was added before startup is unknown. He claims "yes I did" but I can't get confirmation other than his word. Could it be something else based on the info you have.

So the purpose of this thread is two fold 1)Come up with ideas of why there was failure and 2)Eliminate myself as a cause to the problem.

Let's hear your ideas...

JP
 

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Go All Electric
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steve_mk3 said:
I am not sure I follow what it is I am supposed to see on bearing "e"
help please

steve
Bearing E is much less worn than bearings B,C,D.
 
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