engine and drivetrain Leaking Oil Pan

[Stevenc22]

I might have set a record. I have officially changed the oil pan gasket 6 times in 6 months. I simply cannot get a good oil free seal. I have tried black RTV, Grey RTV and cork gasket along with combinations of both and have had no luck.

 

I always clean the mating surfaces properly, have sanded the oil pan mating surface and i still get tons of oil leaks.

 

I'm considering buying a new oil pan but mine does not appear to be warped.

 

Any thoughts on the matter?

[Emyers]

Here is a thought....if the pan bolts have been overtorqued in the past, the bolt holes will deform and the gasket will likely never seal.  Next time you have the pan off look at the holes along the perimeter of the pan. The sheetmetal should be flat on both sides of the bolt hole.  If the sides of the hole appear "pooched out" (for lack of a better term) on the gasket side, they need to be re-flattened.  Lay the sump on something hard and flat.  Take a socket that will fit between the side of the pan and the raised edge and with a gentle tap or two of a hammer on the socket, flatten the sealing surface of the pan.  Do not overtorque the bolts on reinstallation.

Earl

74 02Lux

02 M Roadster

72 Volvo 1800ES

[pilotnbr1]

Is to possible to have a warped pan? Maybe lay a straight edge on the mating surface and check if they are true....

[cj]

Don't use the cork gasket. Get an oil pan gasket from an '84/'85 318i.

[TobyB]

....it's not your oil pan gasket....

 

muhahahhahhaha!

 

t

[OriginalOwner]

 Because the question needs to be asked for perspective:  are you certain it is actually the pan gasket which is leaking, that is, can you actually see the leak path(s) around the gasket ??  

 

That interface is not necessarily a pressure interface, but I see it as a high vibration interface:  considering the weight of the pan and the physics of holding it in place during operation, one needs a very tight "grip" at the interface so nothing moves and thus creates leak path(s).  Hence the large number of bolts holding it in place.  If the pan is wiggling/sliding around during operation, I'm thinking the RTV will eventually break free and the leaks will begin.

 

So as has already been mentioned above, I'll guess the pan is warped.  This could be the whole thing twisted side-to-side, or you've got a couple of places that are not "flat" in relation to everything else.  And the warpage or "unflatness" could be such that the bolt(s) doesn't pull that area into flatness and proper seal.  Or the bolt(s) vibrate loose creating a leak path.

 

Washers:  I suggest using big washers under each bolt head to spread out the hold-down force and help prevent wiggling/sliding.

 

RTV.  I've never used it.  I was raised using Aviation Form-A-Gasket and had good luck with it.  Maybe you will too ??

 

OH, it just occurred to me after reading TobyB above:  maybe you've got a crack in the pan itself ..... or multiple cracks ??

 

Cheers,

 

Carl

Edited January 9, 2014 by OriginalOwner

[jgerock]

+1 if you are referring to a paper type gasket.

 

Hmm.  Quoting did not work this time (using CJ's response).

Edited January 9, 2014 by jgerock

[Stevenc22]

Im ordered the green paper type gasket and im going to make sure all surfaces are straight, all bolt holes are flat and use big washers!

 

I go through valvoline racing oil every couple weeks, jees!

[jimk]

Here is a thought....if the pan bolts have been overtorqued in the past, the bolt holes will deform and the gasket will likely never seal.  Next time you have the pan off look at the holes along the perimeter of the pan. The sheetmetal should be flat on both sides of the bolt hole.  If the sides of the hole appear "pooched out" (for lack of a better term) on the gasket side, they need to be re-flattened.  Lay the sump on something hard and flat.  Take a socket that will fit between the side of the pan and the raised edge and with a gentle tap or two of a hammer on the socket, flatten the sealing surface of the pan.  Do not overtorque the bolts on reinstallation.

Earl

74 02Lux

02 M Roadster

72 Volvo 1800ES

Earl has it right.  It takes more than a gentle tap, my ears were ringing, so I used a small socket and a vise grips to draw the holes back.  Once flat, no leaks.

[mike472]

You are limited in the size of washer you can use and still fit in the channel.  OEM Oil pan bolts can come with a captive washer but early cars don't come with them.  Most likely as everyone else has mentioned the holes are dimpled and you just have to get everything flat.  A nice piece of steel bar stock the right width that fits in the channel is a great thing to back up one side while you hammer the other.