Hi so using the archives I found threads referring to a slow leakage caused by heater hose connections and sure enough I took a peek under the filler tank and posted a couple of pics. I am assuming this is the heater valve so my question is can anyone see what’s wrong from the pics? To me it looks like I may be missing some hose clamps? And what is that little connection where one hose has a stripe? Any help would be appreciated as I don’t have a workspace to remove the tank to get a proper view. I am thinking the issue might also be the hoses to the tank but I can’t see up there, is there a way to tighten those hose clamps?

 

First I can't stress enough. If you have a leak, get a pressure test conducted. It is the best way to locate a leak.
Now, the area beneath the expansion tank contains a lot of hose for the Evap emission system. The heater inlet and outlet are on the passenger side (right side). They are connected to the thermostat tower (front of engine) and run under the intake manifold to the firewall. If you look at the area of the back manifold runner you can see the hoses exit from under the manifold. Also, in that area is the octopus hose, auxiliary water pump, pumps associated hoses.
Follow this link for a look at the hose collection: https://www.jaguarforums.com/forum/x...-hoses-238707/
Follow this link for a look at the heater hoses under the manifold: https://www.jaguarforums.com/forum/x...access-238411/

 

+1 on the pressure test. It will make life so much easier on you and your wallet. However, in spite of that, if your car is still running the original hoses, I'd just replace all of them.


I wish checking for oil leaks were as fast and efficient as coolant leaks with a pressure tester kit.

 

I'm into this now, I just took all this apart yesterday.
From the picture I believe you're under the coolant tank.
I agree with the pressure test because it's possible that the tank itself is leaking but if it's a hose, no matter which hose is leaking I believe your course of action will be the same due to the age of the car.
You're not going to open all that up to replace one hose on a 19 year old car.
I didn't have a leak but I'm changing all of the hoses because of age.
If the leak is from the hose on the bottom of the coolant tank or either hose on the right side of the water valve (on the firewall under the coolant tank), that's the octopus hose. Note that the right side of the car is on your left when you're standing in front of the car looking backwards at it.
If it's not that, there are three hoses that go between the heater connection (two hoses next to each other high on the firewall), the left side of the water valve (two connections), and the coolant pump (two connections) under the water valve. Rock Auto has these hoses. I ordered them yesterday.
Rock Auto also has the valley hoses if you need them but they do not have the octopus hose. That is available from other sources.
My advice is that if you have a leak at one of the three hoses, just replace them all as you need to take everything apart anyway and with the age of your car, you might do what I'm doing....replacing all of them. I got all of them for about $200.00 and I'm doing this only once.
If it's those three hoses or the octopus hose, you're probably removing the throttle body which isn't bad, just label whatever you disconnect.
I have a thread going about my project and if you have any questions, just ask.

 

I'm also chasing a slow coolant leak and will be pressure testing mine tomorrow.

The HF pressure tester I picked up has paid for itself many times over.
I've even used it to power bleed brakes and manual clutch cylinders.

https://www.harborfreight.com/radiat...kit-63862.html

 

Easy as pie. See: https://www.jaguarforums.com/forum/x...3/#post2304896

 

I'm going to buy one of those kits from Harbor Freight.
I had a 30% off coupon that expired yesterday so today I'm kicking myself, but not too hard though because I get Harbor Freight coupons all the time.