Low Oil Pressure, Possible Causes??
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From: Las Cruces, NM
Re: Low Oil Pressure, Possible Causes?? Harlan the turbos should only be using like 1.1 gpm at around 40 psi (WOT). Also the seals on the turbo will only take about 45 psi before you will push through and leak out the exhuast. What do you have your dry sump pump setup for gpm and pressure wise?
Also on some of the early CHRAs Incon added a inline oil orifice. On later CHRA's garrett added the orifice to the CHRA itself, no need for an inline orifice. Dought that has anything to do with your problem, since it was not there before engine work.
Gary
Also on some of the early CHRAs Incon added a inline oil orifice. On later CHRA's garrett added the orifice to the CHRA itself, no need for an inline orifice. Dought that has anything to do with your problem, since it was not there before engine work.
Gary
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From: Olmsted Falls, OH
Re: Low Oil Pressure, Possible Causes?? well
the diagnosis is.....
2 turned mains, 1 cooked and ready to spin, atleast 2 maybe 3 trashed steel caps, one trashed block and one trashed crank.
DOH!! <img border="0" alt="[barf]" title="" src="graemlins/gr_barf.gif" />
the diagnosis is.....
2 turned mains, 1 cooked and ready to spin, atleast 2 maybe 3 trashed steel caps, one trashed block and one trashed crank.
DOH!! <img border="0" alt="[barf]" title="" src="graemlins/gr_barf.gif" />
Re: Low Oil Pressure, Possible Causes?? man that sucks. You should have just left the stock block in there. You had alot of better luck with it. maybe you should go easier on your stuff. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
hope you get it runing again soon.
hope you get it runing again soon.
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From: Olmsted Falls, OH
Re: Low Oil Pressure, Possible Causes?? It was the stock block and crank. Had Katech put in the steel mains.
What gets me is that all the rod bearings were fine, but the mains were trashed. Unless i picked up some trash in the one bearing and it spun. Then the low oil pressure took out the other 2.
I'm already rounding up the new parts. It'll be back on the road soon enough.
What gets me is that all the rod bearings were fine, but the mains were trashed. Unless i picked up some trash in the one bearing and it spun. Then the low oil pressure took out the other 2.
I'm already rounding up the new parts. It'll be back on the road soon enough.
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From: the moon
Re: Low Oil Pressure, Possible Causes?? Sorry to hear that. I thought it was bearings from your desciption of the problem.
But the question is why?
Is it possible those aftermarket caps were somehow at fault?
Steve
But the question is why?
Is it possible those aftermarket caps were somehow at fault?
Steve
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From: LS1.chat
Re: Low Oil Pressure, Possible Causes?? Sorry to hear that.
Did you have Katech align bore the mains with the studs and new caps and did you check the runout on the crank? Do you remember what the runout ended up being?
Hope you get it back together soon. Best of luck.
Did you have Katech align bore the mains with the studs and new caps and did you check the runout on the crank? Do you remember what the runout ended up being?
Hope you get it back together soon. Best of luck.
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From: LS1.chat
Re: Low Oil Pressure, Possible Causes?? Harlan I was speaking of crank straightness runout and not thrust end play. Just wanting to make sure we are on the same page. So, basically, you dropped in the 1 & 5 block bearings, lubed them, droped the crank on them and checked the runout on 3 main, right? I'll have to check what LS1 calls for but an SBC high-speed engine called for no more than 0.0008".
Just asking because main bearing clearance measurements won't mean much if crank runout is off.
Maybe and LS1 engine builder will jump in and elaborate on this for us.
Just asking because main bearing clearance measurements won't mean much if crank runout is off.
Maybe and LS1 engine builder will jump in and elaborate on this for us.
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From: Olmsted Falls, OH
Re: Low Oil Pressure, Possible Causes?? Oh
nope, if it was bent I didn't know. But, it was the same crank and block from my last motor and never had any bearing issues in that motor.
dunno
nope, if it was bent I didn't know. But, it was the same crank and block from my last motor and never had any bearing issues in that motor.
dunno
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Re: Low Oil Pressure, Possible Causes?? I recall you talking about how hard the motor was to hand crank before you had the heads on. I remember thinking sounds bad, should not be that hard to spin over. Good luck!
Re: Low Oil Pressure, Possible Causes?? That really bites Matt. Guess we will miss you on Tuesday <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
How do the plugs look? When that happened to my motor, it was running lean. Melted 3 plugs real bad and trashed 3 cylinders.
Any ideas why I gave up on FI? Too dmaned expensive when something goes wrong. Best of luck getting her back together bradah. We will miss you at Norwalk.
How do the plugs look? When that happened to my motor, it was running lean. Melted 3 plugs real bad and trashed 3 cylinders.
Any ideas why I gave up on FI? Too dmaned expensive when something goes wrong. Best of luck getting her back together bradah. We will miss you at Norwalk.
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From: Olmsted Falls, OH
Re: Low Oil Pressure, Possible Causes?? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cantdrv65:
<strong>I recall you talking about how hard the motor was to hand crank before you had the heads on. I remember thinking sounds bad, should not be that hard to spin over. Good luck!</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">We figured that out. The bores were improperly honed, piston to bore clearance was way off. Should have been the sign of a cursed motor <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Yep Todd, no norwalk for me. Even had the new 3.73's installed friday and got my tires mounted getting ready to hook on a good track.
Car was running great, trapping in the 130's at the track. Just the oil pressure got worse and worse and I didn't crack into the motor soon enough i guess.
But, i got a line on a new block and crank already.
<strong>I recall you talking about how hard the motor was to hand crank before you had the heads on. I remember thinking sounds bad, should not be that hard to spin over. Good luck!</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">We figured that out. The bores were improperly honed, piston to bore clearance was way off. Should have been the sign of a cursed motor <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Yep Todd, no norwalk for me. Even had the new 3.73's installed friday and got my tires mounted getting ready to hook on a good track.
Car was running great, trapping in the 130's at the track. Just the oil pressure got worse and worse and I didn't crack into the motor soon enough i guess.
But, i got a line on a new block and crank already.
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From: Olmsted Falls, OH
Re: Low Oil Pressure, Possible Causes?? Not sure why really, that's the problem
The caps were line honed and doweled in the block. I did check crank endplay/runout, I have the actual number in my build book but don't remember off hand. I do know it was in spec, as were all the clearances in the motor.
For piece of mind, I may just stick w/ the PM mains that come w/ the donor block i get.
The caps were line honed and doweled in the block. I did check crank endplay/runout, I have the actual number in my build book but don't remember off hand. I do know it was in spec, as were all the clearances in the motor.
For piece of mind, I may just stick w/ the PM mains that come w/ the donor block i get.
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From: LS1.chat
Re: Low Oil Pressure, Possible Causes?? Matt - Was it a 1 or 5 main bearing failure and are you running a Rollmaster chain? Can you email me some pics of the bearings or post them?
You used ARP main studs right? You did them to 60ft/lbs?
I did a straightness runout on mine and it was less then .001" on a the stock rebalanced LS1 crank.
Curious & strange that you ate a main bearing so early.
You used ARP main studs right? You did them to 60ft/lbs?
I did a straightness runout on mine and it was less then .001" on a the stock rebalanced LS1 crank.
Curious & strange that you ate a main bearing so early.
