Low oil pressure. Engine builders please. NOT o ring oil pump or barbell plug
11-20-2013, 04:26 PM
#1
12 Second Club
Thread Starter
iTrader: (5)
Join Date: Mar 2007
Location: Shelton, CT
Posts: 79
Likes: 0
Received 0 Likes
on
0 Posts
Low oil pressure. Engine builders please. NOT o ring oil pump or barbell plug Before i start my question might come across as dumb to some people but i have been an ase master tech for over a decade as well as an L1 certified advanced engine specialist and know what im doing.
I bought a 02 z28 in 07 with 20k on the clock all stock. drove it for a while with a 150 shot on it till i snapped a rod bolt at around 55k. I quickly build a motor on a budget immediately. Stock lq4 with wiseco pistons crower rods and a tsp torquer 3 cam. It ran pretty great for around 15k miles made 419 at the wheel. then i started to see a slight drop in oil pressure. slowly got lower till one day bam 0 psi at idle and maybe 20 at MOST while driving. Ive checked barbell plugs and pick up orings and changed the oil pump. This motor makes NO noise while running even at 0 psi. Ive enen danced with the devil and driven it lightly to and from work for prob 1k miles. (i know its dumb but i have the mentality if she really blows than screw it i build it again. I need to get to work) It has a factory gauge and an aftermarket gauge in the oil filter housing. Both read the same. So today i was just messing around quick because it has always leaked a lot of oil from i thought was the rear main seal. oil pan on left side was always covered in oil. i replaced the clutch and flywheel this weekend along with the rear main seal which was leaking. today i found LOTS of oil leaking down over the oil filter and and all down the left side of the pan especially at the rear of the pan. i checked the bolts and almost all of them were almost only finger tight. tightened em and changed the filter. started it and now im getting about 35-40 at about 2k. still very low at idle but this is substantial improvement from just tightening the pan and changing filter.
SO my question is does anybody think the oil pan gasket could be bad and bleeding pressure off badly back into the pan and a little outside the pan causing not a lot of oil to flow up the the galleries? i know the oil comes into the filter housing from the block than back up through the pan gasket into the block again after the filter. i just find it so hard to believe that something right there isnt wrong because the pressure changed so damn much.
BTW i didnt change or add any oil after tightening the pan and change filter. . I also have changed the oil and filter many times with no difference in pressure at all. From what i remember i might have reused the stock pan when i built the motor like an idiot.
Heres a picture of a pan. Its leaking a lot of oil right where those two ports for the filter housing are. when i tightened those i saw way different oil psi readings.
I bought a 02 z28 in 07 with 20k on the clock all stock. drove it for a while with a 150 shot on it till i snapped a rod bolt at around 55k. I quickly build a motor on a budget immediately. Stock lq4 with wiseco pistons crower rods and a tsp torquer 3 cam. It ran pretty great for around 15k miles made 419 at the wheel. then i started to see a slight drop in oil pressure. slowly got lower till one day bam 0 psi at idle and maybe 20 at MOST while driving. Ive checked barbell plugs and pick up orings and changed the oil pump. This motor makes NO noise while running even at 0 psi. Ive enen danced with the devil and driven it lightly to and from work for prob 1k miles. (i know its dumb but i have the mentality if she really blows than screw it i build it again. I need to get to work) It has a factory gauge and an aftermarket gauge in the oil filter housing. Both read the same. So today i was just messing around quick because it has always leaked a lot of oil from i thought was the rear main seal. oil pan on left side was always covered in oil. i replaced the clutch and flywheel this weekend along with the rear main seal which was leaking. today i found LOTS of oil leaking down over the oil filter and and all down the left side of the pan especially at the rear of the pan. i checked the bolts and almost all of them were almost only finger tight. tightened em and changed the filter. started it and now im getting about 35-40 at about 2k. still very low at idle but this is substantial improvement from just tightening the pan and changing filter.
SO my question is does anybody think the oil pan gasket could be bad and bleeding pressure off badly back into the pan and a little outside the pan causing not a lot of oil to flow up the the galleries? i know the oil comes into the filter housing from the block than back up through the pan gasket into the block again after the filter. i just find it so hard to believe that something right there isnt wrong because the pressure changed so damn much.
BTW i didnt change or add any oil after tightening the pan and change filter. . I also have changed the oil and filter many times with no difference in pressure at all. From what i remember i might have reused the stock pan when i built the motor like an idiot.
Heres a picture of a pan. Its leaking a lot of oil right where those two ports for the filter housing are. when i tightened those i saw way different oil psi readings.
11-21-2013, 08:01 AM
#3
if it has been leaking for a long time it very well could have cut a grove in the gasket sealing the pan to the block ports.
In my opinion you have something else bleeding off pressure maybe cam bearing, oil pump check valve.
did you cut the filter apart?
In my opinion you have something else bleeding off pressure maybe cam bearing, oil pump check valve.
did you cut the filter apart?
11-21-2013, 08:10 AM
#4
12 Second Club
Thread Starter
iTrader: (5)
Join Date: Mar 2007
Location: Shelton, CT
Posts: 79
Likes: 0
Received 0 Likes
on
0 Posts
Ya my first hunch was a cam bearing. I have cut 2 filters apart and have no metal in them. Also i have already replaced my ported ls6 pump with my stock one. Made no difference whatsoever
11-21-2013, 11:54 AM
#5
TECH Enthusiast
Join Date: Feb 2007
Location: Raleigh, NC
Posts: 625
Likes: 0
Received 0 Likes
on
0 Posts
Tightening the pan and the oil pressure coming up has root caused the problem. Your oil pan was loose. (duh)
However, whether or not any other damage was created by running it while the oil pressure was low will only be known if you pull it apart and look at it.
I doubt that the oil cut a groove in the aluminum pan, it's possible, but it's very unlikely. Oil pressure and flow is not high enough to erode aluminum, not even a soft aluminum which is what the oil pan gasket is made from. Most likely the oil just wept out slowly though a long thin gap. To erode the aluminum, the oil would have to be coming out so fast and at such high velocity that the entire contents of your oil pan would be covering the entire drivers side engine bay in a very short period of time. If you were running hydraulic system pressures (5000 psi) and flows (30GPM - 100GPM) typically found in construction type machinery, then sure, cutting a groove would be no problem at all. Cutting a groove 45 psi and a few GPM? Not likely in my opinion.
If its got enough oil pressure now and is not making noise, I'd just keep driving it. Granted, if there is something wrong, doing so will only make it worse. If you want to feel more comfortable you can always shim the oil pump bypass valve for more system pressure.
However, whether or not any other damage was created by running it while the oil pressure was low will only be known if you pull it apart and look at it.
I doubt that the oil cut a groove in the aluminum pan, it's possible, but it's very unlikely. Oil pressure and flow is not high enough to erode aluminum, not even a soft aluminum which is what the oil pan gasket is made from. Most likely the oil just wept out slowly though a long thin gap. To erode the aluminum, the oil would have to be coming out so fast and at such high velocity that the entire contents of your oil pan would be covering the entire drivers side engine bay in a very short period of time. If you were running hydraulic system pressures (5000 psi) and flows (30GPM - 100GPM) typically found in construction type machinery, then sure, cutting a groove would be no problem at all. Cutting a groove 45 psi and a few GPM? Not likely in my opinion.
If its got enough oil pressure now and is not making noise, I'd just keep driving it. Granted, if there is something wrong, doing so will only make it worse. If you want to feel more comfortable you can always shim the oil pump bypass valve for more system pressure.
11-21-2013, 06:29 PM
#6
Did you properly line up the front and rear covers with the block and oil pan? If the rear covers hang down below the block too much, you won't get a good seal around the oil ports between the pan and block.
If that's the case, you have only partially solved your problem.
If that's the case, you have only partially solved your problem.
