Hi

I'm planning to fit my shiny new Miltex exhaust this weekend and I'm sure one of my Cats rattles. I know it would be easier to change the Cats when I fit the exhaust but I don't want to/have the money to buy the Cats now.

So I was wondering how is easy are they to remove as I would like to take them off and give them a good shake. But if they are really fiddly I might what until I can buy the replacements.

Can I just unplug the sensors and drop them off, or do I have take the sensors out in order to take them off?? My experience of working on this engine is everything is very tight!!

 

Well, once you have set the expectation that exhaust work is generally among the least fun jobs, it is mostly going to be about the status of the fasteners (rust). You have to remove 4 nuts off of the exhaust manifold. Nothing terrible, oil spray is your friend. Then you have 2 more substantial nuts at the bottom. More torque, again, depends on rust. The are are 2 more screws for a bracket, and 2 more to get the bracket off of the bell housing. Last, and here is the trick, make sure you disconnect the pipes off of the cats on BOTH sides. The studs on the cats are quite long and you cannot get enough play to disconnect a cat by itself. Once it is all loose, you have to follow the leads of both O2 sensors, and disconnect them. They should be resting on posts right behind the throttle body. Keep mental notes of which plug goes where because right side and left side sensors are the same, with the same plug, but need to be plugged properly in the harness. I suppose you would have to go out of your way for this, but you could possibly plug a right side sensor on the left side harness and cause a lot of confusion for the engine management.

Also, depending on rust, be ready for some form of Plan B. You could snap a stud off, discover a leaky gasket, etc.

Best of luck. Keep us posted.

PS: Find a way to update your signature with your car's details. Mush easier for folks to help you going forward.

 

Thanks sounds no worse then I thought, I have got WD40, a selection of imperial sockets to hammer on once the metric ones round off, and (hopefully not required) a good chisel.

 

laguillotine,
If you don't plan to replace your Cats, why mess with them? Hook-up you Millek's! That's enough for the week-end.....When you get the money to do the Cat's, take the Cat's and the Manifolds off and throw them away......They are just a bunch of Junk! Get some XJR Manifolds, they are more streamlined and flow at an angle out the back instead of making those 90 degree turns like the XKR.....then get a couple of short 200 Cell Cats from Magnaflow and have someone that can TIG weld build you a new set of down-pipes to match-up with your Milltek system...The Cats will cost around $125.00 each but they will release a lot more power than the Jag system.....It's like having a stopped-up nose and....when you get all that crap out of there, you can breath again....There is a lot of Horsepower stopped up in the XKR system......You can do all this for less than the cost of one Jag Cat....They cost around $1,200. to $1,500. each.....Good Luck to You!

Billy Clyde in Houston

 

Well that is the plan long term when I have the funds, Hi flow cats are not so cheap in the UK, for now I want to put the exhaust on and remove the annoying rattle/prove my engine is not the the annoying rattle.

 

The right-Hand Cat is usually the one that rattles.....It's the core..as it has broken-lose from the canister...These Cats have a 400 cell core, whereas the After-market ones have 200 cell cores...In other words, the Bee-Hive holes are twice as big as the stock holes....Hence, more flow! Also, the Cat is much shorter than the Jag's!

Also, if you change to the XJR's manifolds, in the USA you will need to extend the EGR tube by increasing it's length so that it will fit....

Billy Clyde in Houston

 

I listened to each cat with using a bar against my ear with pointed to the left cat, just took it off and internals are loose.

Apart from being tight everting has come apart quite easy. Some of the exhaust clamp bolts sheared off but that is not an issue, and I have used lots of WD40 both on the bolts and joints. The centre box took quite a bit hammering to get off as being twin pipes you cant rotate it.

Next problem is getting the over axle sections out, they are off but I cannot get them out! I think the car needs jacking up higher.

 

Darn, I was hoping this thread would enlighten me as to how to keep someone's cat from occasionally sleeping on my convertible top at night. I know because I see his dirty paw prints.

 

Apparently male human urine is an excellent cat deterrent! I might just try in the veg garden one day...