i bought my 00 disco knowing it had an exhuast leak, i just wasnt sure where from, the sound is hard to locate. well i dropped some intake cleaner in to see if any white smoke could be seen seaping out, and sure enough, its the collector gaskets and not the manifold gaskets.

now, according to rave there are 3 bolts, 3 nuts and a gasket for each side. i bought them all, but i was surprised by the bolts. they are threaded at each end, with a smooth buldge about 1/4 the way in (so one threaded side is about twice the length of the other)





ive never encountered these before, but i assume one side screws up into the headers, the gasket sits in that smooth spot, and the nut screws on the other side... question is, how does one torque it (or even screw it in) in te first place since it has no place for a socket to grab onto?

and being that these are part of the exhuast system, how the hell do you get the old ones out on the one side... normal bolts usually require lots of penetrating oil, leverage and sometimes even a torch to get out, so im a bit perplexed... this job might require more work then i though. i figured it be a matter of crawling under, unscrewing a nut, putting a bolt out, sliding new gaskets in, and tightening her back up... but ive never come across a double threaded do-dad like this.

can someone walk me through what needs to be done? if it required removing the manifold i might pass for now! alldata doesnt even list the gasket surprise surprise.

heres what i assumed the setup is like, and what i now think it might be... can someone fix it to what its actually like? i dont see how one could torque something properly if u cant use a tool on it

top black being header end, bottom black being ypipe end, yellow gasket, red bolts, grey nuts

 

Those are called studs.
Since the heads are aluminum they should come out with vise grips or pliers.
Spray the threads that are in the head with pen-lube and then remove the bolt, you might find that the bolt is rusted to the stud enough that it will just unscrew with the bolt still attached.
Make sure you take note of which threads go into the head, short or long.
As for how tight, screw them in until they wont turn anymore by hand, then when you tighten the nut it will turn the whole stud until it all bottoms out and tightens up.

 

ahh i didnt even see that the nuts crimp down towards the back... another wierd overly complicated failed design for land rover

so the diagram on the right is correct after all?

penlube... never heard of it. will antiseize be sufficient, or perhaps graphite or pb blaster?

can this be done without removing the manifolds and ypipe like i hope?

 

Pen-lube... penetrant/lubricant, like Liquid Wrench, PB Blaster, etc.

Studs are used on many things not just Rovers.
No you should not need to remove the y-pipe and the like, but I have never done this job so I cant say for sure.

 

PB Blaster should work. If you have trouble getting the studs out of the manifold, you could either double-nut them (find 2 nuts that fit the studs, screw both nuts onto a stud, tighten them together with two wrenches, then put the wrench on the upper nut and begin turning it counterclockwise. Since the nut top nut is locked against the bottom nut, it cannot unscrew from the stud, and the whole stud will begine unscrewing from the manifold.)

OR

Use some channel-locks or vise-grips to remove the studs from the manifold. It won't matter if you bugger the threads since you are replacing them, anyway.

If you have trouble putting the new studs into the manifold because the manifold threads are less than perfect, use the same double nut idea, and tighten the stud into the manifold using the bottom nut.

 

very good gentlemen.

curious though, is there a factory torque spec for these? yes, im that **** hahaha

 

Nice and tight for the torque spec and the other.

 

im **** enough to the point where that statement will drive me insane

 

Download the RAVE service manual, it has all the torque specs.

 

i did, cant find those... exhuast is page 99 (06-8) but im not sure which one they could be or what they are called.