svsgt1

Hey guys, I have a questions. I just built a fresh LS1, stock block and crank but aftermarket pistons, rods, heads, cam, etc etc. I have a ported LS6 oil pump. I started the motor and heat cycled it a few times. EVery time I started it I had great oil pressure, about 55psi at idle. I took it to get tuned and after 2 hours noticed the oil pressure got pretty low. After the session was over I was only running about 13psi at idle at operating temp. The car never ran on a dyno or had load on it. We were just getting it to start and rev in neutral. So I went home and figured I would change the oil. I did and then started it up again and had even lower oil pressure, like 5psi. (Have an Autometer Guage) I shut it off within a few seconds to avoid any more damage.

My guess is that I have some sort of bearing failure or wear due to an improperly put together motor (I built it) and that is causing the bearing gaps to open and loose oil pressure. I have a magnetic oil drain plug and noticed a good amount of metal shavings on it. But I have no clue as to know what is a normal amount for a fresh build. Should there be virtually no shavings? I have the old oil, is there a way to use that to diagnos the problem. Should I strain it and see what I find or is that a waste of time. I'm obviously going to pull the motor out to get to the pan and oil pump.

My next line of questions are, what shoudl I check? I was told to check the rod side clearance first before I take anything apart. After that what else should I do? Any advice would be helpful.

Thanks,
Adam

Viper

iTrader: (6)

I had metal shavings my first oil change too, but more a silver sludge than actual shavings. 2 things you can do. 1 is cut open the filter and see what's inside and 2 is send the oil to blackstone labs for analysis.

vetteboyc5

iTrader: (9)

I had the same thing viper described on my first oil change. A silverish tinted oil.. it wasnt like a enormous change, but when i emptied the bottom of the drain pan I saw the silverish fluid and made a similar post.

Im at 10k on this motor with good pressure- So should be good to go.

Are these actual tangable shavings? like you can FEEL them in your hand or just like this metalic sludge like buildup? If your feeling shavings it could be left over from the oil pump porting? I had allot of shavings from my porting on my oil pump.

Its normal to have some metal in the oil at first, thats why your suppose to change it within the first 500-1000 miles breakin. Different people do it different ways I chose 1000 beacause I forsure wanted the rings to seat. I changed the oil and filter at that time.

Keeping in mind- Oil pressure is greatly affected by the temperature On the corvettes we have oil temperature sensors... ive seen my oil get up to 230 F before. Pressure goes down significantly.. at cruising speeds its arround 180F to 205F anything over I see about a 10psi loss. You said it was tuned and ran on the dyno? the oil could have been hot from this session.

The gm manual says 10psi per 1000 rpm is acceptable but if you can hit arround 50 at wide open throttle you should be ok too.

Just giving you food for thought here.

LS1Formulation

iTrader: (13)

Also, when I did my heads/cam, I accidentally put the WRONG o-ring on my oil pump and had horrible oil pressure at idle. I had to tear back into the engine and put the larger size o-ring on it to fix it. Maybe this could account for your poor oil pressure?

chevy2808

what are the shape of the metal shavings? you can usually tell by the shape of the shavings whats going wrong...

svsgt1

Well the car never drove on the dyno. We only got it running and revving correctly. When I changed the oil and started her, it was the next day so it was definietly cooled down by then and the oil pressure was even worse.

The metal shavings were all on the magnetic drain plug and I did NOT notice a metalic tint to the oil. The shavings were super fine and when on the tip of the magnetic drain plug, it looked like spikey hair, of course very short and fine. I just grabbed the metal with my hand and brushed it off.

So I definietly have a pressure problem as it seemed to get worse and worse. So either the o-ring or some gasket worked and then came loose or I have some major bearing wear which caused the pressure to drop. I guess either way I have to pull the motor and take a look. Its a mid-engined flat bottom car so I can't just take the pan off.

I think I'm going to check the rod bearing side clearance and the o-ring first. And then start taking things apart.