Upon tear down and inspection of my first performance engine:

MentallyChallenged

MentallyChallenged

Banned
Well I'd like to get some input to confirm my assumptions.

I tore my engine down because of a bent crank snout causing an oil leak. Upon inspection with a dial indicator the crankshaft snout was .004 out of round. The 2-4 main bearings have copper showing at opposite sides of each bearing. The #1 and 5 main bearings look great and barley have the coating worn off. It seems to me like I got a bad re-ground crankshaft.

After taking my oil pan and pump off I found pieces of a spring in the pan and even larger pieces of a small spring between the oil pump housing and the rear main bearing cap. The oil pump teeth are all torn up from said spring passing through it, but this said spring is to large to get sucked through the oil pump pickup screen. :dontknow:
 
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The large springs on the left are the ones between the oil pump and rear main cap and the pieces on the right were in the pan. Both are magnetic.
 

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fastredgmc said:
about how much power was this engine?
what was it reved to?
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A rough guesstimate 400-430ish hp, and I accidentally revved it to 6700ish a couple times in the burnout box. Didnt make power past 6000r's. I wouldnt want to spin it any higher anyway with the cast pistons and un-balanced (stock) rotating assembly.

It put down 300hp to the rear tires through a 4L60 and 2000 stall. So 430 at the crank I think is a good guesstimate.
 
Just what i thought. That 4th main appears to be shifting back and forth causing those wear marks (Cap walk). The two main bolts arn't just holding it enough at that power level. Is the any metal transfer where the cap meets the block or any strange marks?

350hp @ 6000 rpm is about the safe limit for your setup there to last a good amount of time.

but if it put down 300 thats only 350-370 fwhp.

hmmmm.....
It could also be caused by in correct torque.

if you have a dial bore gauge check to see of its out of round at all.

I just get a 4 bolt block to have some better priece of mind and so it might be able to handle any upgrade later on
 
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fastredgmc said:
Just what i thought. That 4th main appears to be shifting back and forth causing those wear marks (Cap walk). The two main bolts arn't just holding it enough at that power level. Is the any metal transfer where the cap meets the block or any strange marks?

350hp @ 6000 rpm is about the safe limit for your setup there to last a good amount of time.

but if it put down 300 thats only 350-370 fwhp.

hmmmm.....
It could also be caused by in correct torque.

if you have a dial bore gauge check to see of its out of round at all.

I just get a 4 bolt block to have some better priece of mind and so it might be able to handle any upgrade later on
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The hp was on sean@CARS dyno, its known to be very stringent. It put down 400ft. lbs. though too.

The main walk sounds logical enough. Although I know for sure this machinist has fucked up cranks.

I do not have a dial bore guage. I'll look for any odd marks on the mains. I may just let this thing sit untill I can afford to build it properly.
 
fastredgmc said:
damn 400ft lbs at the wheels is getting up there. This is just a 350 right?

what cam & heads if you dont mind sharing
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Stock vortec's modified for more lift, This cam: http://www.compcams.com/Technical/Search/CamDetails.asp?PartNumber=12-432-8

with solid lifters. I'm switching to hydrulics if I put this motor back together. About 8.5/9-1 compression. Ran well on 89, never tried 87. Only had 165 or so cranking compression.
 
Any ideas with the srping? Its boggling my mind where it would have come from. And it is a spring too, it's just been mutilated. I was thinking possibly from the oil pump itself, but I dont know.
 
Looks fimilar I have pretty much the same setup but am using the hyd flat tappet extreme enery 224/230 cam.

Mine runs just fine on 87 my cranking comprision is high 160's-low 170's

The few times i took it to the track i was doing 14.30's just under 100mph on regular radials. My truck probally wieghs around 4300
 
HemiChallenger said:
Any ideas with the srping? Its boggling my mind where it would have come from. And it is a spring too, it's just been mutilated. I was thinking possibly from the oil pump itself, but I dont know.
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in the pics those look like metal shavings to me. probally left over form machine work and the lack of a good wash
 
fastredgmc said:
in the pics those look like metal shavings to me. probally left over form machine work and the lack of a good wash
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No doubts its a spring, It looks just like a spring out of a spring loaded pen. I guess maybe something crazy happened and it got into my engine some how.
 
when stuff is machined it will make little "springs" chips or shaving


I build/machine engines for a living and thats exacly what like it looks like. Its to small to be anything to be used in a engine. IT could be some foriegn debris that somehow got in there.

inside the engine you have valve springs, a pressure relief spring in the oil pump and a little spring inside the lifters on the hyd ones but you have solid.
 
HemiChallenger said:
Any ideas with the srping? Its boggling my mind where it would have come from. And it is a spring too, it's just been mutilated. I was thinking possibly from the oil pump itself, but I dont know.
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Looks liek a stretched out seal spring from one of your many balancer seals. all that damage look cosistent with a betn cranksshaft IMO.
 
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