Hi everyone,

This is my first post to Jaguar Forums. I have a XJ6 Series 1.
I'm having problems with the car getting quite hot in the cabin after about 20mins of driving.

I've changed the heater tap/valve on my car, as I still had the original and it was leaking a little when closed.

I was hoping that replacing the heater valve would have fixed the problem.

I just wanted to put a call out to anyone who has similar problems or any ideas on troubleshooting/fixing the problem?

Thanks in advance
Cheers
Michael

 

Hello
I had a similar problem with a ford inline 6 engine years ago it turned out to be a vacuum hose which was faulty. I'm sure someone will have more jag related info on here but just my two cents. Cheers and good luck

 

Behind the radio are the hoses that connect to the heater controls. The rubber goes bad = leaks. They are "odd" sized compared to most parts store hoses so make sure they are correct = not too big or they will not seal. Since vacuum opens and closes the heater controls to let water flow through the heater matrix, there must be a good seal and proper working control switch.

Be very careful with the plastic nipples on the controls - no new parts are available. We have to fix the broken nipples by inserting small brass tubing from a model shop into the old holes and seal up with epoxy.

Or, just get rid of the old Jag vacuum controlled heater stuff and convert to a modern electronic heater servo from Vintage Air. I have photos and information if you are interested. Have them on both S1 cars now for years. It retains the stock heater knob and looks stock from inside the car.

 

A couple of thoughts:

1. All vacum operated heater valves are not the same. In some the default, no vacum applied means closed to water flow. In others, it is the exact opposite.

2. I altered my S3's system a bit. One heater hose has a generic valve. works just fine. I installed another under the bonnett manual valve in the other hose. So, with both in "off" there is no hot water in the heater matrix. I can run the fans and get power ventilation in summer when AC isn't quite needed. Oh, my AC is all hooked up, but not evacuated nort charged. Some day??

 

Thank you for the replies guys.

I'm led to believe the heater valve I installed in my opens when vacuum is applied. So as far as I know now water should be going to the heater core to heat.

But there is certainly air still coming through the vents in the car. They don't come through instantly but after about 10 - 20 mins of driving.

I'm wondering if the fresh air intake is open? I can't find a switch for it (it's supposed to be above the radio?)

Upon further inspection of my car, it looks I have no vacuum working within the heating system. What can I do to confirm this?

Thanks again everyone for your help

Cheers
Michael

 

Note all the vacuum lines going to the heater controls and the air controls. You will have to pull the radio to be able to see behind it and check the
lines and the control nipples. You can apply vacuum with your mouth to the controls to check if they are holding/opening.

If you find something broken, let me know as I have fixed/replaced or converted all heating and AC stuff several times!

Note the Clippard valve is a replacement for the vent control that you cannot find? It is brass and has hose fittings...the only (2) two vacuum lines I have in my
S1 now behind the radio.

 

Thanks for that Roger.

Looking at the heater controls behind the radio unit. The fresh air control has been disconnected. The two plastic nipples have broken and the vacuum have lines have nails in the ends to block them off. The heater control looks to be in good condition and so do the vacuum lines connecting them.

I’ve tested the vacuum line for the fresh air intake, I can hear the flap closing when applying vacuum. So it seems I need to find a replacement fresh air controller somehow?

 

I may have a good repaired spare one for you.... just want to make sure we are talking about the same part.
Sounds like the part that I/we replace with the brass Clippard valve. The brass valve and two nipples cost
less than $20.00 USD and you only have to make a simple bracket. It uses your old lever...

 

Hello All,

Firstly, Happy Australia Day to all my Aussie friends!

I've done a bit a search and have read a lot, but not seen any pics of the Heater Control Valve repair using some brass tube. If anyone has a pic or maybe a sketch to illustrate the method of repair, that would be great.

It sounds pretty simple but I don't want to completely destroy a valve in the process.

Advice appreciated.

P.s. I like the alternate valve option above!

 

And to you Woz.

 

You can insert model train brass tubing into the existing plastic nipple holes. Use epoxy and wait 24 hours for it to totally dry.. then adapt your rubber hose to the new smaller tubing. This assumes that your valve holds vacuum now when it is applied and the lever moved back and forth to test? These parts are only available used now.. I have a working unit that has not been repaired since there are better solutions made out of brass.

Or, get rid of all the plastic and use a brass Clippard valve. I got mine from Howell Company Inc, 818 526 4510, 1912 West Olive Avenue, Burbank, CA 91506...in 2007 it was $19.23 including tax and shipping to my house. Part numbers were TV-3S (my receipt shows TV-2S but I wrote the other number next to it for some forgotten reason? I believe that #s valve got rid of the vacuum better for closing the outer center vent??) Clippard 2-way toggle valve and (2) 11752-3 Clippard 10-32 hose bards that screw into the valve and have rubber O-ring seals. They do not have a website (at least in 2007, old fashioned company with good phone person and delivery - products first class).

You then make a bracket like the picture, cut off the handle on the lever to fit and use small screws, washers and lock nuts to hold on the handle.

Let me know if you need more information...

 

Happy Australia Day, my first as an Australian. Got my citizenship certificate yesterday.