Oil Leak - likely culprits?

[Dillzio]

Hi all,

My eight year old LS1 is leaking oil, NOT HAPPY! It's done 162,000 Kms

I drove it 700km recently (in one day) and it lost 1 and a half litres of oil over the trip.

When i got to my destination, i got my roccer cover gaskets done for the pretty penny of $200. On the way back another 700km later it didn't seem to loose much oil at all, but it still seems to loose a drop here and there. I've also washed the undercarridge of the car and it still seems to be leaking.

I'm thinking that it might be the rear main seal (tragically!). Does anyone have any experience with what the "problem gaskets" often are on these engines?

-cheers

[German Statesman]

Any 8yr old engine is going to be prone to oil leaks, BMW, Rolls Royce, Holden or otherwise. Gaskets are made out of organic materials like every other bit on the car, and these break down with time.

Try the sump gasket, try the oil pressure switch and the rear main seal you mentioned

[vxssgurl]

Check that the sump plug isn't cross-threaded. Apparently it happens a lot. In a hurry to get it done, don't pay attention, keep threading, bastard gets tight, use a little mechanical assistance, and bingo! empty sump in less than a week... less in warm weather.

If it is your sump plug, your sump alone is going to be dirty - most of it around the plug.

Rear main will be bleedingly obvious once you get her on the hoist - there will be oil EVERYWHERE... even in the sill channels and on the front of the your pipes from wind carriage... but I doubt it would be your rear main - otherwise 1-1/2 litres over 700 k's would have resulted in a pressure sensor alert on the dash... had any of those?

[Dillzio]

No, no engine error codes either.

I though that the engine oil pressure won't be effected until the oil gets well below the 'ADD' range?

[jezza85]

I did a rear main seal in the calais at about 160,000kms, it wasn't to bad just a few drops in the drive way every now and then I left it for about 20,000kms before I got it fixed.
Did some shopping around and the price difference between mechanics was huge the most was $2200 but I managed to get it done at a holden dealership for $1300 with a two year warranty on parts and a six month warranty on workmanship.
Rear main seals are petty common on chevy engine's

[Micks]

Rear main leaks are common on anything...

Cheers
VYT

[mosoto]

Last service I had the Pwr Steering pump rebuilt & the Oil sender replaced FOC due to leaks at these points. The last leak left is the rear main. I was quoted $1400 by Holden which I thought was kinda steep, apparently not :shock:

[Dillzio]

Yeah, i've noticed that LS1 parts really are unnecessarily expensive. Back when i rebuilt my VH 308 a gasket kit for the whole engine was about $50. On the LS1 it costs $45 for each rocca-cover gasket, god knows how much it is for a complete set!

I guess the labor involved in taking the motor apart to get to the rear main seal would be where 90% of the cost would be anyway :-(

I think that since the holden dealers are set up so well to do the work on their cars they can do a job like this more easily than most mechanics, so they can charge less.

I'm thinking that getting mine done at a dealership would be the way to go.

Does anyone know what the sump gaskets are like on these engines? If i'm gonna get the rear main done, i might get them to do the sump gasket too.

-cheers

[mosoto]

I believe the high cost encompasses the fact the gearbox has to be removed.
If you're replacing the rear main seal you might as well get them to do the sump gasket, removing the sump and cleanining out the "deposits" would be a good idea too.

[jasonmi]

I got a 5.7 and at 170 000 it got to the point where it was leaving more than a 50 cent piece size spill on my floor every morning. Took it to holdens they said it was the rear main and the sump. And wanted 1800 to fix it, however got an exholden worker who has his own workshop to do it for $900 which pretty much stopped the leak however now at 190 000k's a 5cent piece appears on my driveway everynow and again. All gen3's are prone to leak especially from rear main, thinking of taking it back and questioning the quality of work they have performed??
all the best

[greg1959@bigpon]

hello i have a gen 3 in a vx with 270000 on the clock
my first oil leak was the rear seal at 180000
then the rocker covers at 200000
and finally the sump and front timing cover at 260000
besides the oil leaks has been a very relible car

[mosoto]

Last service I had the Pwr Steering pump rebuilt & the Oil sender replaced FOC due to leaks at these points. The last leak left is the rear main. I was quoted $1400 by Holden which I thought was kinda steep, apparently not :shock:

Ha, apparently Holden got it wrong, suprise suprise........Rocker cover seal leaking down the side of the block and they told me it was a rear main.......... and I bet had I booked it in they'd still charge me for a rear main and fix the rocker cover :flipoff:

[vz300]

Oil leaks under the joint between the sump & bell housing are either rear seal or the rear oil seal housing gasket. The latter is the main problem.The rubber tends to come away from the alloy gasket carrier around the rear camshaft opening under the cover.The sump gasket is made of the same material.This,I guarantee is the reason for your leaks as I have just replaced both gaskets & guess what.....no more leaks.The rear main seal is very rarely the cause of your leaking problem.

Cross threaded sump bolt??????Who are these gorrila's?Never heard of it-in fact in all my 58 years,I have never heard of a cross threaded sump bolt let alone a reason for oil leaks.It simply does not happen.
Gaskets & correct bolt tightening sequence is designed to keep oil inside the engine,simple as that.The only reason oil leaks OUTSIDE is because these items wear out through old age & heat.
If you need to replace the rear main seal on a GEN3,buy the rear housing -Part number GM 12615666.It comes complete with a new housing,12 bolts,a new housing gasketl & a new rear main seal already installed.The sump gasket number is GM 12558760 & should also be replaced at the same time.Install the housing after you have done the sump,as you need to draw the rear housing down on the gasket surface of the rear sump by tightening up the (2) long bolts.Make sure the lip of the new rear seal has a coating of clean engine oil so as to make it slip easily over the the crank journal.It will be centered on the crank once the lower bolts are tightened before you tighten the (12) housing bolts.Job done!!!!

[Dillzio]

Oil leaks under the joint between the sump & bell housing are either rear seal or the rear oil seal housing gasket. The latter is the main problem.The rubber tends to come away from the alloy gasket carrier around the rear camshaft opening under the cover.The sump gasket is made of the same material.This,I guarantee is the reason for your leaks as I have just replaced both gaskets & guess what.....no more leaks.The rear main seal is very rarely the cause of your leaking problem.


You called it VZ300!
:kneel:

As Brad from Enhanced found, it was indeed the "rubber coming away from the alloy gasket carrier around the rear camshaft opening under the cover"

Maybe we should make VZ300 the quiz-master?

[r8ls1]

Yeah, i've noticed that LS1 parts really are unnecessarily expensive. Back when i rebuilt my VH 308 a gasket kit for the whole engine was about $50. On the LS1 it costs $45 for each rocca-cover gasket, god knows how much it is for a complete set!

-cheers

Holden make big profit on many ls1 parts & gaskets. but that price for the rocca covers is not bad actually. US price is $28 pair + freight so they will run you $65 - $75 to get them yourself. other items is not the same story, the head gaskets for instance holden overcharge a lot, or used to when i was buying them. maybe recently they dropped their prices seeing as their on the verge of closing their doors.