another oil leak question
 

Hi anyone reading this,

I have a 1997 xj6 lwb 3.2 I think I got it for a great price and have had fun tweeking the odd thing here and there.

I have just replaced the valve cover gasket and plug o rings and stopped a leak coming from the cover all sealed good and no leak from there but there is an oil leak from somewhere I cannot see top of engine by firewall drips down onto the exhaust no and then there is a brown stain on top of bell housing
would appreciate some advice as to the possible cause
maybe around starter motor? or what? just annoying me that the jaguar is bleeding oil

btw great price was $100 nz dollars .... 140k immaculate interior just the hood lining needs replacing which I have done before in a series 3 I owned
fully road worthy I couldnt resist the give away and use it every day never let me down...so far

Did I read this correctly, you paid $100 for it????

You are NEW, so welcome aboard.

Good pick up there in any opinion.

When the camcover gasket was renewed did you apply some Hi-Temp RTV to the "D" seals thet are built into that gasket????. That is the area they will leak forever, and it will drop exactly where you say it is.

Since the bolts that hold that cover in place is a set parameter due to them being "shanked" bolts. BUT, the seals on the top of the cover that those bolts pass thru, SHRINK, so that "crush" is lost and oil leaks out. ALWAYS renew those seals which will retain the crush pressure on the other gaskt/s.

I used a fibre washer under the head of each of those bolts on mine a long time ago, as a temporary fix until new bolt seals arrived, and it worked a treat. It just gave that 1mm more crush on the whole thing.

thanks for answer
I applied rtv to those areas i read the forums here and they are i think well sealed

still have the oil thought it may have been from another area? but I cant think where

yep the princely sum of 100 nz dollars....nothing really

the guy thought he had major engine problem....i replaced one ignition coil and noted oil in the plug so replaced the seals as well...runs beautifully.
just a few little niggles to sort the oil leak being the annoying one ...the radio knob comes off easily when turning volume...I think for the price i am happy as the cd stacker and radio work really well...

Wow! That's the once in a lifetime deal we all hope to find, great pick up! As for the leak, given where the oil is showing I'd say it's still from the cam cover region, they're a menace. I used permatex ultra black on the rear half moon seals and it still isn't perfectly dry but I live with it.

Welcome to the forum. Check post#3 by motorcarman in the thread below for another possible leak source.

https://www.jaguarforums.com/forum/x...6-4-0l-132893/

I think you gave me a "aaaa haaa" moment i will give that try as you are quite right those washers were ancient and very hard
where did you get your new ones from if you recall i will look on ebay but if there is anywhere that stocks or if they are a standard size for other vehicles may be easier for me to find
Thanks very much

I luv those aha moments.

It usually requires copious amounts of JD to sort out.

I got them from JagDaim in Melbourne from memory HAHA, but I am probably correct, as I get most my bits from there as needed, when push comes to shove and Genuine is the only way out.

Part # NBC2575CA, and you need 13 of them.

sigh....
Thanks for the idea of the washers and that extra crush I think that was the problem but now a new development....
when tightening the bolts ever so carefully so as to not over tighten and cause stripping of the aluminum head one of the bolts snapped! just old and fatigued wonder if any one has had this happen to them or am i the luckiest person ever...sigh another job drilling out a broken bolt...carefully...never done that before any tips anyone?

Hi choco43,

Your broken screw is not unheard of. Hopefully if you remove the cam cover you'll find that it isn't difficult to get the broken end to thread out of the head by using a small screwdriver to push rotationally on a rough edge on the end of the screw. Worse case, you'll learn how to use an "Easy Out" or other screw extractor tool, just take great care not to scratch any part of the cylinder head, especially the gasket surface or a camshaft lobe.

Off the top of my head, I think the screws are M6 size. You can replace them all with stainless steel equivalents for not much money. McMaster-Carr is one source (mcmaster.com).

To help reduce the incidence of oil leaking from around the screw heads, I replaced all our washers with stainless-steel/neoprene sealing washers from McMaster-Carr. I think I used the No. 12 size washers shown at the link below:

McMaster-Carr


Note that the factory torque specification for the cam cover screws is not tight at all. I seem to recall that it is in the inch-pound range, so as you've learned the hard way, it doesn't pay to over-tighten them.

Cheers,

Don

As Don said, though, since you are dealing with a bolt that is probably NOT corroded or cross threaded, then it should back out with minimal effort.

When you decide you need to drill, use a center punch on the remaining bit to get the bit aligned. Be VERY careful whilst drilling since the bit is small and you will probably be in a tight, adverse position and breaking the bit in there is a much bigger PITA!

And, to answer your question, yes, most of us have broken 6mm bolts in an engine, but it is not because the bolt were "just old and fatigued", but rather that WE were young and had not yet learned the pain of extracting one! As Don said, they don't take much torque. I don't know if you think in inch pounds, but the specified 60 inch pounds (maximum) is like a force of 10 pounds at the end of the common 6 inch wrench. About what two fingers can transmit without a strain

Thanks for your help much appreciated

I have looked at the link you supplied and located the stainless steel bolts i think they are a great solution...will have to remove one and measure the shoulder length for ordering the correct size.
Thanks again

I don't know if you will find shoulder screws of the correct length, but personally I don't think it matters if the entire length of the screw is threaded if you use those sealing washers. They've worked fine on our car for the past several years.

Be aware that at McMaster-Carr you will find that these fasteners are called screws rather than bolts, because McMaster uses the definitions of the American Society of Mechanical Engineers: A screw is a threaded fastener tightened by its head into a threaded receptacle. A bolt is a threaded fastener onto which a nut is tightened. Some but not all screws can be used as bolts, and some but not all bolts can be used as screws. The terms don't define the fasteners; they describe how the fasteners are used:

The difference between a screw and a bolt by The Engineer


And this concludes our lesson for the day. :icon_special:

Cheers,

Don