LS1 low oil pressure

**blue1964vette** · 07-07-2006, 09:29 PM

I have a 383 LS1 in my 64 vette built by a local engine builder. It has about 200 miles on it and has only about 25# oil Pres cold and very little at idle warm. The block was new and did not even have plugs in it when bought. I don't remember buying the "barbell Oil restrictor" and wonder if one was installed, would it still build pressure but drain off at idle? or could I have a suctionleak with my pickup tube? I used an SLP oil pump. I am open for any hints.
Thanks,
Steve

**cailey37** · 07-08-2006, 10:02 AM

You may want to check and make sure that your builder put the barbell restrictor on and not just a plug back there.....can't imagine that it would be a problem with the oil pump........I run a SLP on mine and I get around 60psi.....

**blue1964vette** · 07-08-2006, 08:15 PM

Thanks, I am afraid that may be whats wrong. I reeeally hate to pull the trans but oh well.

**blue1964vette** · 07-08-2006, 08:16 PM

Also what have you done to engine, sounds good!

**cailey37** · 07-09-2006, 06:24 AM

It sucks but it beats losing the motor.........good luck with it....

**fastrthanurs** · 04-19-2007, 08:49 AM

what do you mean by barbel restrictor? any info? i have one that is doing it when it warms up but is fine when it's cold i'm hoping it's not a bearing.

**RE98TA08** · 04-20-2007, 05:28 AM

pinched o ring

**fastrthanurs** · 04-20-2007, 10:26 PM

where was the o ring? mine is idling around 40 45 with the stock gauge and when it warms up the pressure drops to 20 then 10 then 0. and if you rev it the gauge wont move. i'm thinking it is the sending unit. gonna pull it and hook up a manual gauge.

**0rion** · 04-20-2007, 11:21 PM

Like was said above.
I've read where a pinched o-ring on the pickup tube will do this. The pressure will be ok for a little bit then drop dramatically when the o-ring fails. Either way I wouldn't risk the motor and find out what it is before running it anymore.

**fastrthanurs** · 04-21-2007, 05:54 AM

and if the o ring was on the pickup you had to pull the engine correct?

**fastrthanurs** · 04-21-2007, 03:46 PM

put the manual gauge on it today and idled fine until it warmed up and dropped to around 10 and then a little lower than that and stayed there. any opinions? i guess i'm going to pull the pump and see if the oring is damaged and sealing. any other hints or suggestions? can i get to the oring by just pulling the timing chain cover?

**0rion** · 04-21-2007, 11:02 PM

when it was cold what was the pressure? I would think a failed o-ring would be kinda low all the time unless the cold thicker oil is helping with pressure.
Yeah, front cover has to come off and you have to drop the oil pan. Not sure what kind of k-member clearance you have on that car though so it may be different.

**Rivi** · 04-22-2007, 06:10 AM

gm's bulletin on this says normal oil pressure cold and loud ticking lifters with low oil pressure hot is symtoms of the oring damage.The lifters tick because air gets introduced into the oil through the oring damage.

**fastrthanurs** · 04-23-2007, 03:18 PM

when its cold the pressure is 35 to 40. idling. then drops to 25 then 20 and so forth. stays between 5 and 10. i cut it off there didnt want to risk anything to see if it would drop lower. any ideas? i'm going to support the engine with a stand on the top of the engine and drop the kmember so i can get access to drop the pan and stuff. anything is appreciated as far as ideas.

**Rivi** · 04-23-2007, 04:13 PM

are the lifters ticking?

**fastrthanurs** · 04-24-2007, 03:22 AM

it has a little top end noise but the car has a jesel top end so it is solid.

**fastrthanurs** · 04-26-2007, 11:31 AM

anymore input or ideas?

**tblu92** · 04-29-2007, 12:14 AM

You don't need to drop the pan to get to the -o-ring on the pick-up tube--It is in front of the engine --visible with removal of the timing cover---

**fastrthanurs** · 04-30-2007, 03:41 AM

ok. i droped the kmember and pulled the pan and all the parts on the engine. had alot of gasket maker and the oil pan was a little drity but the puckup screen was ok as well as the oring. oil pump didnt look too new so i put a ls6 oil pump on it and cleaned everything up. hopeing that was my problem. needless to say it wasnt. idled around 50 psi then droped to about 7 when the engine reached 200. so i'm stuck i'm thiking cam bearing? any more ideas or anything.