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Discussion Starter #1 (Edited)
If you saw my thread, I've swapped cam, oil pump (Melling 10355), had heads worked (WCCH) and new clutch. I went over the oil pump set up about 10 times to ensure I had all the clearances correct and torqued it per the Melling/LS requirements and when I started the car everything was perfect 50+psi on cold start up and operating temp at idle its been 26psi+ . I've been driving the car to get the break in miles needed for the clutch and working on the tune, nothing overly aggressive. So I'm finally over 300+miles and have done the 1000+ shifts McLeod wanted for break in, and have the tune where I need to log some WOT pulls. Fuck Yeah! Been waiting on this. Last night I go out and bang out 2-3 WOT pulls up through 4th gear (and its a spin fest in 2&3 even with NT05r) but none the less car is strong.! I get to a gas station and top off (more weight needed) and pull 4 blocks of ice in my UH tank (planned on trying this to see IAT2s). Anyway go back out and do 3-4 more hard pulls on the way home and everything is happy. Cooling it down the last 3-4 miles home and give it just one blip of the throttle to 3500 let off and hit a stop light, and I notice as soon as I come to a stop my oil pressure is @13-14psi? and then drops to 10... I'm like WTF? I touch the gas and it comes up only to 20ish but idles back down and I'm seeing 9-10.? I'm only a mile or so from my house so I gently get it home and park. Once in the garage I can hear the engine cooling and realize it was HOT.. (Not overheating just HOT). I leave it till this morning and start it back up cold, and the oil pressure is normal for cold 46ish, and I let it idle to warm all the way up and pressure starts dropping, and with it almost at normal operating temp the pressure has dropped to 19-20psi. I did the break in oil change after I put all the new stuff on it (ran it for 10-15 min then drain) and added the oil I've been using for the last yr, RedLine full syn 5-40. There is NO knocking (that is at least audible), not missing, runs fine just the oil psi. Am I running the wrong oil? Stock bottom end and all the rest as stated above. This is a FL car so it gets hot down here. What next? I have read many of the oil threads but have not seen this issue or missed it.

Heres my build thread http://www.ctsvowners.com/forum/5-transmission/133721-gettn-old.html

Edit; Shifting @6k, Miles 88k, Blower puley set up, 8.6/2.45 @15-15.5psi
 

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Not enough information - but based on oil pressure alone with a Redline 5w40, I believe you're fucked. DON'T DRIVE THE CAR - just in case you did spin a bearing. With that said - I'm a cynic so don't freak out yet: you know the drill....

Pull the oil filter and check for the infamous gold glitter.
The oil pickup tube / o-ring is also on the differential list since I believe you had to tinker with that on the cam install.
 

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Man - hate to hear this. Followed your build thread and I hope you figure this out. Hopefully the low oil pressure is some kind of leak. Isn't there a pressure limiting mechanism in the oil pump? One that releases excess pressure? I wonder if the relief valve could be malfunctioning somehow?

And go ahead and park the car and cut open the filter and inspect carefully. You could get an oil sample and send it out to see what's in it. If the filter looks ok the oil sample might provide some clues without tearing down the engine. But it won't help you fix whatever is wrong.

Keep us posted...
 

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Damn sorry to hear about this.

I have the same pump on my current build.
 

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Discussion Starter #5
Not enough information - but based on oil pressure alone with a Redline 5w40, I believe you're fucked. DON'T DRIVE THE CAR - just in case you did spin a bearing. With that said - I'm a cynic so don't freak out yet: you know the drill....

Pull the oil filter and check for the infamous gold glitter.
The oil pickup tube / o-ring is also on the differential list since I believe you had to tinker with that on the cam install.
Yeah, the filter was going to be my next step. I've spun rod bearings before on other car (my GN) and there was a knocking for sure. So I'm think you mean mains? Yes I installed the o-ring like 5 times (only because i had to remove the pump 3 extra times) an I'm positive it didn't get rolled or pinched because I was aware that would be a self-inflicted wound and didn't want that.
What other info do I need to add? Pulley set up, shift points..?
 
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Discussion Starter #6
Man - hate to hear this. Followed your build thread and I hope you figure this out. Hopefully the low oil pressure is some kind of leak. Isn't there a pressure limiting mechanism in the oil pump? One that releases excess pressure? I wonder if the relief valve could be malfunctioning somehow?

And go ahead and park the car and cut open the filter and inspect carefully. You could get an oil sample and send it out to see what's in it. If the filter looks ok the oil sample might provide some clues without tearing down the engine. But it won't help you fix whatever is wrong.

Keep us posted...
Thanks Tri. Of course the words one of my old school (pre LS life) buddies said while I had it tore down to a short block was... just pull it the rest of the way and freshin the bottom end.. fuck, fuck, fuck... I sure hope to prove him wrong. hope..
 

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Yeah, the filter was going to be my next step. I've spun rod bearings before on other car (my GN) and there was a knocking for sure. So I'm think you mean mains? Yes I installed the o-ring like 5 times (only because i had to remove the pump 3 extra times) an I'm positive it didn't get rolled or pinched because I was aware that would be a self-inflicted wound and didn't want that.
What other info do I need to add? Pulley set up, shift points..?
I was referring to pulling the filter as the obvious next step - so we're really just waiting on that aren't we?

Smart ass! :D


Hurry up already and rip off the proverbial band aid... the suspense is killing me.

ETA what were your shift points?


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Discussion Starter #8
I was referring to pulling the filter as the obvious next step - so we're really just waiting on that aren't we?

Smart ass! :D


Hurry up already and rip off the proverbial band aid... the suspense is killing me.

ETA what were your shift points?


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It's going to sit today.. wifey stuff. 6k for shifts..

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Man, what a kick in the nuts. I'm getting ready to do first start after my timing chain tensioner fiasco. Hoping at least one of us can break the mod curse, haha.
 

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Discussion Starter #11
Man, what a kick in the nuts. I'm getting ready to do first start after my timing chain tensioner fiasco. Hoping at least one of us can break the mod curse, haha.
No shit.. wish you the best.. This totally knocked the wind out of me last night at 11pm.. talk about no sleep.. I've went over everything I did to be sure I didn't miss something.. The only good thing is the wife knows this means a lot to me and whatever I have to do to fix its cool. What really sucks right know.. I'm fixing to drop about $20k in to my pool and patio from Irma damage. Orig estimate was 10k of which FL insurance laws allow the deductible to go to 2% of insured value with a named storm. So my deductible was $6200. and of course we added stuff because it needed updating. AWW FUCK! Might start looking for a short block that has been freshened up..
 

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Discussion Starter #12
Doesn’t sound good. A lot a variables though.

In for the oil filter inspection.
Yup on the variables.. filter pull tomorrow..

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Discussion Starter #14
Hey if you end up checking the pickup o-ring, might want to look into the Improved Racing brace, which helps a lot to seat the o-ring evenly. I have it on my car! LS Engine Oil Pump Pickup Tube Brace / Clamp EGM-500
I'll keep it in mind if/when I go back in.. I was only bleeding money before I finished this project.. I feel like there is fixin to be more blood shed...

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Well I'm rootin' for ya! My first test drive went well, so time will tell if I have your same fate, haha.
 
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Well I'm rootin' for ya! My first test drive went well, so time will tell if I have your same fate, haha.
Me too! Hoping to find time in the next 2 to 3 weeks to do my cam install along with a new pump.
 

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Discussion Starter #17
Me too! Hoping to find time in the next 2 to 3 weeks to do my cam install along with a new pump.
Yeah thanks.. I'm going to hook up my mechanical gauge and start it an see before I pull the filter an cut it open. Have to get a pipe cutter to for the filter.. If the outcome is still low psi an nothing noticeable in the filter.. timing cover will be 1st move.

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Good idea on the mechanical gauge..;)

Grab a magnifying glass,
then cut the filter open and drain your oil.

If you paid as much attention to the oil pump as you stated above,
it's most likely the O'Ring.

Then pay attention to post #13.

Good Luck..:eek:

Cheers
 

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Discussion Starter #20
Good idea on the mechanical gauge..;)

Grab a magnifying glass,
then cut the filter open and drain your oil.

If you paid as much attention to the oil pump as you stated above,
it's most likely the O'Ring.

Then pay attention to post #13.

Good Luck..:eek:

Cheers
At this point I'd love nothing more than to say I f-d up the o-ring and the bottom end is ok.. Right now it makes no noise, as i'd expect to hear something to indicate something went wrong in the short block...
 
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