Elusive Oil Leak

[jonegar]

My wife's 2001 Lesabre is going through about a quart of oil between oil changes. I was confused about this as there is no smoke, or oil dripping from the bottom of the car. I discovered the oil is pooling on top of the engine just to the front of the intake manifold and literally boiling off as the car is driven. (there are some small recesses in front of the intake manifold - the engine cover must be removed to see them) Has anyone seen this before? The intake seal appears to be intact. There are some small threaded fittings that protrude from the top side of the engine ( I have no idea what they do or why they are there) near the valleys that the oil is pooling in. Could they be the culprit?

[pcmos]

Are you talking about the area where the injectors sit? It always helps to see a photograph if you could link to one it would be a lot easier to understand. By process of elimination though if the oil is in that area around the fuel rail / injectors, it almost has to be leaking from the intake or valve covers. I'm not really sure I understand your description of the threaded object. A photo would really help identify everything. I would suspect either valve cover gaskets or lower intake seals.

[HotZ28]

Originally Posted by jonegar

My wife's 2001 Lesabre is going through about a quart of oil between oil changes. I was confused about this as there is no smoke, or oil dripping from the bottom of the car. I discovered the oil is pooling on top of the engine just to the front of the intake manifold and literally boiling off as the car is driven. (there are some small recesses in front of the intake manifold - the engine cover must be removed to see them) Has anyone seen this before? The intake seal appears to be intact. There are some small threaded fittings that protrude from the top side of the engine ( I have no idea what they do or why they are there) near the valleys that the oil is pooling in. Could they be the culprit?

Typical signs of oil traveling through the bolt threads. You need to remove & clean each bolt (one at a time) clean and put thread sealant on the threads to stop the leak. This is nothing new, it has been happening for 60-yrs!

[C man]

I have the same issue with the oil travling up the bolts. Been like that since I got the car 49k miles ago and it had 108k on it then. Has not gotten worse or better. It was burning 1qt/1200miles when I first got it. Since then I have changed the PCV valve, oil pan gasket, valve cover gaskets and valve stem seals. The valve stem seals were bad and the oil pan gasket leaked but not bad at all the rest was fine. I didn't see any improvements in oil consumption until I replaced both sides of the engine valve seals. Now it seems that the oil counsumption has dropped to about 1qt/2.2k miles. Big improvement for me but a lot higher than what most people experience or are comfortable with for this engine.

My biggest concern is the intake manifold. It was replaced in 2003 and I got the car in 2006 and now its 2009 and it hasn't went bad with 49k of my own miles. It could be part of the high oil consumption problem but who knows? It has also consumed a small amount of coolant since I bought it. In either case neither has gotten worser or better(well the oil has). Just waiting for it to fail, not really, or wondering when it will since it seems past due.

[Jrs3800]

The other oil leak that can present as a rear main is the rear cover plate... At times the bolts can loosen over time and leak to a certain degree.. When you remove the trans for any reason we make sure those bolts are tight to ensure no leaks..

[jonegar]

Originally Posted by HotZ28

Typical signs of oil traveling through the bolt threads. You need to remove & clean each bolt (one at a time) clean and put thread sealant on the threads to stop the leak. This is nothing new, it has been happening for 60-yrs!

Last Thursday I had time to do my own oil change and spend a little quality time with it. I removed the oil pooling in the valleys I mentioned and gave the engine a good wash-down at the carwash so I could have a better look-see. (*pcmos - yes, they are close to the injectors). My mechanic mentioned the bolts as being the culprit but he passed away before I could have him look at it. I will try the remove,clean, reinstall with sealant, fix. Is black RTV ok for this? And what are these bolts for anyway?

[HotZ28]

Use Loctite Teflon thread sealant, or Loctite http://www.loctiteproducts.com/produ...id=48&plid=153

[jonegar]

Thanks for the tip!