I have seen several recommendations to replace the plastic crossover outlet pipe (on the 4.0) because it is plastic. However, I have only been able to find the same plastic ones to replace it. In which case, what is the point? I can see replacing the plastic thermostat housing with a metal one. And replacing the water pump with the plastic impeller with one that has a metal impeller. But I don't see much point in replacing a plastic pipe with the same plastic pipe. So, please enlighten me.


Thanks

 

It hardens and goes brittle over time with repeated heating/cooling cycles.

Graham

 

. . . and then begins to leak. Mine did.

 

XKs Unlimited , $ 55. Alloy Thermostat Housing Kit. Plenum needs to be lifted to get to two bolts, as I've been told. Rich

 

Jaguar XJ8 XK8 uprated Aluminum Thermostat Housing Kit AJ82217 100 Feedback | eBay

From SNG Barratt $39.99 with free shipping

Jaguar XK8 XJ8 uprated Aluminum Thermostat Housing Kit AJ82217 w Thermostat | eBay

$60.69 with thermostat, also free shipping

Be sure to paint it black as a bright aluminum one sure stands out on an otherwise all black engine.

Jag Parts (Coventry West) had the best price on the cross over pipe.

I've replaced two without lifting the manifold. That can lead to other problems.

 

You should not need to move the plenum, as said already, that leads to more issues/costs.

 

If the plenum is like min 03, there is a metal plate on the front, 5 bolts holding it I think it is. Remove that then the back bolts are easy to get to and out, again assuming the set up onmy 03 is the same as yours which I think it is.

 

See if this link helps on how to do it. A metal thermostat housing is available but the crossover is not. This is assuming that your car is a 1997

Link JagRepair.com - Jaguar Repair Information Resource

The crossover can fail and on my car it did I have a picture of it in this link

Link JagRepair.com - Jaguar Repair Information Resource

 

What problems dose removing the plenum cause? I was thinking of doing that in order to replace the heater hoses.

 

No problem just means extra work and gaskets.

 

Thank you for the excellent photo directions on pump removal. About the best I've seen on DIY. Three questions: 1. I noticed on the new pump there were two new bolts. Did you break two bolts on installation? 2. What is the proper temperature rating for the thermostat? I've seen them offered from 170F to 183F. 3. What MY and how many miles did you have on your XK8 when you replaced the pump?

 

Would a crows foot spanner work on the back bolts?

 

The ones you show may not because of the wraparound open end.. The space above when removing the bolt will not allow you to remove the crows foot to reposition it that is why the open end wrench works.

 

https://www.jaguarforums.com/forum/x...ousing-119815/


Greenforest, Have a look at this thread and it will add a bit to the other great directions.

 

The good news is the original style Crossover pipes have come way down in price recently. now just $35.32 -Discount.

www.sngbarratt.com/ProductDetails.aspx?id=ca25e33b-5554-4255-bf62-8d8a0130b18e

 

SNG Barratt: Where were you 3 weeks ago when I needed you? Paid about $50 shipped.

I bent a 5/16" box end wrench, same size as the 8mm, so that it fits over the bolts.

On the assumption that I am never going to need it again I will send it postage paid to anyone with an upcoming thermostat tower replacement provided you promise to send it to the next person that needs it.

I made a ground down 1/4" 8mm socket a number of years ago for the same purpose and forwarded it to the first person that asked for it never to be heard from again.

We could create a thread with contact information as to last had it and where it was sent so others might find the information. Use the wrench and bump the thread to the top for others to see.

 

Back to the original question: As stated, these plastic parts get very brittle, or even soft with age. I just replaced one today that had 85k on it. It has seen a lot of use. The ends where the hoses attach were "brown" colored, and the plastic also had a split which leaked under pressure. These old plastic parts can also be easily broken with very little pressure, such as tightening a hose clamp, or even bumping a hose barb with your hand. Not any of these would be much fun on a fun weekend away! Replace your plastic part for another 85,000 miles of fun!

 

Ok, thanks for all the feedback. Now, since you've got the pipe and the housing out, any advantage to replacing the knock sensors and temp sensor? Easy to get to at this point. I was also going to replace the drive belt and tension pulley since they are not that expensive.

 

The temp sensor comes with the cross over pipe, or at least mine did.

 

For what its worth I have to say that If your changing the cross over then change the thermostat housing, knock sensors and the valley pipes. When I did the cross over pipe I had a look at all the hoses and realized they had never been changed. In my mind if its a "keeper" then do the right job and replace all these items to ensure one doesnt fail on you.