Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Major Oil Leak.??

Thread Tools
 
Search this Thread
 
Old Jun 19, 2009 | 10:23 PM
  #1  
1stz06's Avatar
Thread Starter
TECH Regular
iTrader: (18)
 
Joined: Jun 2006
Posts: 452
Likes: 0
From: Houston, TX
Default Major Oil Leak.??

A friend of mine has had some major oil leak problem for the last few days. He asked me to come over and I was shocked to see so much oil coming out of a car.

He has a stock 99' Z (90K mi) and it appears to be leaking from the driver side rear of the engine. When the car is off it drips oil a little here and there but once it's running, it starts streaming oil almost immediately.

The only thing I can think of is a rear main seal but I can't imagine so much oil coming out. We checked plugs, valve covers, oil sending unit and a few other misc. things and still have no idea what or where it is coming from. This is his DD so we are trying to get him back on the road.

ANY HELP IS GREATLY APPRECIATED.!

Cheers.
J.R.
Reply
Old Jun 19, 2009 | 10:26 PM
  #2  
massls1guy's Avatar
TECH Fanatic
iTrader: (9)
 
Joined: Nov 2005
Posts: 1,311
Likes: 0
From: Mass
Default

I would check the oil pressure sending unit. It's located on the top rear of the engine just behind the intake manifold on the driver's side.

Here's a picture of it. It's the black round post thing sticking up in the back - has a white elec connector:


Last edited by massls1guy; Jun 19, 2009 at 10:33 PM.
Reply
Old Jun 20, 2009 | 09:38 AM
  #3  
1stz06's Avatar
Thread Starter
TECH Regular
iTrader: (18)
 
Joined: Jun 2006
Posts: 452
Likes: 0
From: Houston, TX
Default

We did check the sending unit since he recently changed his but it was bone dry.

Thanks for the suggestion.

J.R.

TTT
Reply
Old Jun 20, 2009 | 11:23 AM
  #4  
dlandsvZ28's Avatar
TECH Fanatic
20 Year Member
Photogenic
 
Joined: Jun 2003
Posts: 1,869
Likes: 99
Default

You said driver's side so unlikely it is the oil dipstick tube that has worked it way out of the block because the bolt fell out or the clamp is broken.

But without the dispstick tube inserted completely into the block it will make a mess of your engine bay in a hurry and also give you false oil readings on the dispstick.
Reply
Old Jun 20, 2009 | 11:58 AM
  #5  
1stz06's Avatar
Thread Starter
TECH Regular
iTrader: (18)
 
Joined: Jun 2006
Posts: 452
Likes: 0
From: Houston, TX
Default

Originally Posted by dlandsvZ28
You said driver's side so unlikely it is the oil dipstick tube that has worked it way out of the block because the bolt fell out or the clamp is broken.

But without the dispstick tube inserted completely into the block it will make a mess of your engine bay in a hurry and also give you false oil readings on the dispstick.
Ohh yeah, we checked his dipstick tube since his was loose but.....it wasn't the issue.

Oil is coming down from the mid to upper rear of the engine and coming down the bell housing. I have a hard time believing it is the rear main.
Reply
Old Jun 20, 2009 | 03:26 PM
  #6  
kdick91's Avatar
TECH Regular
15 Year Member
iTrader: (1)
 
Joined: Dec 2008
Posts: 417
Likes: 20
From: Houston, TX
Default

Torque the oil pressure sending unit!!! Get the right adapter and get that sucker on tight! I had that EXACT same problem. A TON of oil was coming out, so much that it was ejecting from the sender, leaving it bone dry. Like it baffled me until I went out bought the socket adapter and torqued it down. No more oil
Reply
Old Jun 20, 2009 | 03:28 PM
  #7  
1stz06's Avatar
Thread Starter
TECH Regular
iTrader: (18)
 
Joined: Jun 2006
Posts: 452
Likes: 0
From: Houston, TX
Default

Originally Posted by kdick91
Torque the oil pressure sending unit!!! Get the right adapter and get that sucker on tight! I had that EXACT same problem. A TON of oil was coming out, so much that it was ejecting from the sender, leaving it bone dry. Like it baffled me until I went out bought the socket adapter and torqued it down. No more oil
Well put brother.! I am going to give it a try. You stated with with enough conviction I would be foolish to pass on your advise.
Reply
Old Jun 25, 2009 | 11:39 AM
  #8  
1stz06's Avatar
Thread Starter
TECH Regular
iTrader: (18)
 
Joined: Jun 2006
Posts: 452
Likes: 0
From: Houston, TX
Default

Originally Posted by kdick91
Torque the oil pressure sending unit!!! Get the right adapter and get that sucker on tight! I had that EXACT same problem. A TON of oil was coming out, so much that it was ejecting from the sender, leaving it bone dry. Like it baffled me until I went out bought the socket adapter and torqued it down. No more oil
I had him go back and torque the sending unti down and VOILA.!!

Thanks for your help.

Cheers.!
J.R.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 02:05 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE