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No real engine carnage this time (thank god because I don't want to spend 10K on a 388 LSX, even though I really want one). Just finally got to figure out m low oil pressure issue. My oil pressure has been gradually dropping as the weather has warmed up. At idle, it has gotten as low as 6 PSI, at which point I only drove the car to the shop to pull the oil pan. This is what I found. Be careful who you have install your parts. (I don't know who installed this cam as it was installed when I bought the car, but obviously they were in a bit over their head.) No bearings, cranks, or rods were hurt in the production of this post.
 

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That motor has a melling pump in it?
 

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That motor has a melling pump in it?
I'm not sure as I only pulled the oil pan to check, so I couldn't see what kind of oil pump it has. I'll find out when I do my cam in a couple of weeks.
 

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Glue it back together and toss it up for sale on Facebook?
Never! Oil pressure is actually 100% fine now, a miracle considering it's been ~10-15 PSI @ hot idle for a year. Currently at 28-30 PSI hot after driving for about 45 minutes.
 
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I'm not sure as I only pulled the oil pan to check, so I couldn't see what kind of oil pump it has. I'll find out when I do my cam in a couple of weeks.
If it's a black o ring it's probably a melling. The blue oring is GM from what I understand.
 
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If it's a black o ring it's probably a melling. The blue oring is GM from what I understand.
From what I understand the o-ring isn't dictated by the pump, it's dictated by the style of pickup. I think all pump orifices (he he) are the same diameter to ensure cross compatibility between models. The Melling I have came with all 3 color o-rings. black, red/orange, and blue. I heard the aftermarket blue ones were a little stiffer than the OEM ones, so I just stuck with OEM.
 

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So have you cut the filter just to ensure there wasn't any trash in it? I'm guessing the pan was clean? Mine never showed up at idle but one time, and by then it was too late for me. But looking back at my data that I logged, the psi was not keeping up in the upper RPMs (4000 and up I only had 38-40psi). Yes I pinched the o-ring during my cam install, and I'll say that doing the cam without pulling the pan, (which most do not) is a PITA because most cams are 3 bolt and you need to swap the timing chain and gear, which means the oil pump is coming off and access sucs to the bolt and being able to see that the o-ring isn't pinched.
I'm very happy you found it before it caused any damage... thank your lucky stars.! lol It only took 3-4 hard pulls up through 4th gear for me to trash mine. Although the bottom end has cleaned up and going back together with new rings, bearings, ARP bolts, new-new Precision Melling oil pump, another set of new-new Johnson 2110 lifters and what not (and added more clearance for oil .002+) it is still going to hurt some with the $$$$.
Good Luck, Jeff
 
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So have you cut the filter just to ensure there wasn't any trash in it? I'm guessing the pan was clean? Mine never showed up at idle but one time, and by then it was too late for me. But looking back at my data that I logged, the psi was not keeping up in the upper RPMs (4000 and up I only had 38-40psi). Yes I pinched the o-ring during my cam install, and I'll say that doing the cam without pulling the pan, (which most do not) is a PITA because most cams are 3 bolt and you need to swap the timing chain and gear, which means the oil pump is coming off and access sucs to the bolt and being able to see that the o-ring isn't pinched.
I'm very happy you found it before it caused any damage... thank your lucky stars.! lol It only took 3-4 hard pulls up through 4th gear for me to trash mine. Although the bottom end has cleaned up and going back together with new rings, bearings, ARP bolts, new-new Precision Melling oil pump, another set of new-new Johnson 2110 lifters and what not (and added more clearance for oil .002+) it is still going to hurt some with the $$$$.
Good Luck, Jeff
I cut the filter about 6 times since the low oil pressure manifested itself. The only material was some brass from when I installed the CHE trunion bushing kit. The running oil pressure got up to about 40-45PSI MAX when driving. At about 2000 rpm it was ~38-40 PSI. The bottom of the pan was clean (besides the remaining dirty oil and a piece of the O-ring). I'm sure there is some metal in it somewhere because I had 2 rockers fail (probably due to oil starvation/lack of lubrication) about 2 months ago and I developed a lifter tick. I'm going to pull the cam and swap in my BTR PD III Torque cam, lifters for my Lunati 72437 Link bars, Rollermaster timing set, IWIS timing chain, ARP head bolts, and Melling oil pump in a few weeks.

I was kinda looking forward to the LSX 388 though...:( . That was going to be paired with a Huron TT kit probably...maybe...It would have been cancer causing Ramen for the next 3 months, but my car is fast :)
 
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From what I understand the o-ring isn't dictated by the pump, it's dictated by the style of pickup. I think all pump orifices (he he) are the same diameter to ensure cross compatibility between models. The Melling I have came with all 3 color o-rings. black, red/orange, and blue. I heard the aftermarket blue ones were a little stiffer than the OEM ones, so I just stuck with OEM.
The black o-ring that comes with the Melling pump that I have yet to install is a lot stiffer than the OEM blue o-ring that I have.
 
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The black o-ring that comes with the Melling pump that I have yet to install is a lot stiffer than the OEM blue o-ring that I have.
I just went and checked, and you are correct. The Melling 10355 comes with a black and a green o-ring. Now I wonder what oil pump is in my car.
 
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