I suspect I may be typical of many purchasers of used S-Types - while I could afford to buy the car, if I waited until I could really afford to own the car, I never would. So I accepted the reality that, if at all possible, I will be doing repairs and maintenance. I also live a long way from the nearest Jaguar dealer, so it isn't a matter of simply dropping in to the pick up spare parts.

When I bought my S-Type six months ago the heater didn't work but the A/C did. Summer was coming on so I thought I would get to it later on.....

Suddenly winter arrived and I hadn't done anything about it except do a lot of reading and gazing down into the engine bay with a sense of trepidation. It was obvious that, apart from having no heat, the auxiliary water pump was leaking, so I had to get in there. So I took a punt that the problem would be the DCCV, bought one in and started burrowing my way downwards into the engine bay.

The first thing that was apparent was that the leaking water pump had been masking leaks in the DCCV. The second thing was that one side of the DCCV was blocked and the other side was jammed shut. And the third thing was that the resistance of one DCCV solenoid was 0.6 ohms and the other was 3 ohms. This is a lot less than the 15 ohm nominal resistance of the coils. I have noted there have been many comments that the over-current protection of later model A/C control modules isn't very good, but my unit seems to have survived the abuse. At the same time I was replacing the DCCV, I thought I would see if I could do anything about the auxiliary water pump. It was surprisingly easy to pull apart and a 43mm ID by 2 mm CS O-ring set it right.

The first attachment is an image of the old DCCV.

So the car was back together and I was very happy....for one day. Then I got out my torch, thinking I was just going through the motions of checking for leaks and discovered a puddle in the bottom of the engine bay. One of the heater pipes which runs past the exhaust manifold had a leak. This was a pinhole underneath the forward-most mounting bracket. A temporary patch got me going again but over the next few days both of the other pipes developed leaks.

At this point it simply wasn't an option for me to source a replacement pipeset so I had to seek an alternative.

So I pulled the car apart again and ran 5/8 inch (16 mm) heater hose directly to each of the two outlets of the DCCV. The challenge was to run the hoses via a route where the heat from the exhaust manifold wouldn't destroy the rubber. I ran it up close to the top of the strut mounting and then back to the firewall. I carefully cut the hoses off the pipes at the firewall end and used 5/8 inch barbed brass hose connectors to join the new heater hose to them. The return line is 3/4 inch (19 mm). I used brass hose connectors at both ends to insert a length of 3/4 heater hose, also routed as high up as I could manage. The second image shows the arrangement of hoses, with engine covers removed to aid visualisation.

I am sure the purists will be horrified, but I have heat and cold as required, I have no leaks and I can still just about afford to eat this week - so I am a happy man.

 

Glad to hear that you managed to resolve your issues. I must admit that's the roughest-looking DCCV I've ever seen!

 

Being able to eat matters more than being purist, is my take. I hope what you've done can take the pressure, for it is designed as a pressurised system.

There are other Australians on here & the UK forum in case any happens to be close(ish) to you.

 

The rating of the heater hose is 10 Bar, which is 145 PSI. Given that the specified radiator cap pressure is 16 psi, I would be very worried if the pressure of the cooling system exceeds 145 psi! I used very high quality brass hose connectors and good quality stainless steel hose clamps, so all should be well on that front.

 

Excellent. Just wanted you to at least have thought it through - didn't mean to say you hadn't.

 

I was very confident I had covered all bases, but I will admit for the first few hundred kilometres I kept a very, very careful eye out for a 'Low coolant level' warning message and I watched the temperature guage like a hawk! I also had a lot of spare coolant in containers and a mobile workshop in the boot, just in case.

 

Where do you guys buy your DCCV valves from? Is it a dealer part only?

 

The later DCCVs of the three-outlet type are BOSCH part number XR8 40091.


I bought mine from a private Jaguar/Daimler parts specialist here in Australia, which probably wasn't the cheapest way to go about it, but they had them in stock.


They are always on offer on E-Bay - prices on new ones generally seem to range between about US$110 and $160.

 

Congrats on mending it, Roger. You probably did this already, likely as part of your DCCV R&R, but I'd run several courses of distilled water up to temp in that system then refill with appropriate coolant. Maybe even try a flush solution depending the looks of the water after several drains. That crap plugging your old DCCV is likely randomly distributed throughout your cooling system.

 

^ Yes I concur with what aholbro1 said! ^

 

Would this be the same part number for a 2007 STR?

 

I think I effectively did a flush, although not necessarily quite in the way you describe. In my description above I left out a couple of steps in what I did. In reality I pulled the system down four times (first time because I thought I was just fixing the leaking aux pump and testing the resistance of the DCCV, second time to change the DCCV - at which time I flushed the heater core, third time to bypass the pipe that was leaking, fourth time to bypass the other two pipes which revealed leaks two days later). The first time I released the coolant and replaced it with new. While on the next several times I husbanded as much coolant as possible by syphoning it out of the header tank and the radiator, inevitably I lost a couple of litres each time. So one way or another I think I have done a fair clean-out of the system.


You make a very good suggestion, though, so I will add a full flush to my 'to do' list.


Thanks!

 

Yeah, you may want to take another crack at it when the weather is nice and there's some beer in the fridge. If memory serves me correctly, I believe I went through 12 gal of distilled water, about 2 at a time when I flushed our 03 3liter. Drain, top up with distilled, run to optemp and drain again. I think I could only get about 2 gal in after draining...I just kept going til I was getting clear water with no hint of pink out. Then use straight coolant, not the 50/50 mix because you'll already have nearly half a system full of distilled water in there.
It's probably actual goodness- running with fresh coolant a short time before you flush it, maybe some of that sludge will dissolve back into solution and come out the drain. Not sure what that stuff is clogging your old valve, maybe someone mixed a non-compatible coolant with the Jag-pink? Seem to recall reading that it forms a jelly-like substance when you do that.

 

Here's one of many sources. I believe the proprietor may be a member of this forum.
Buy a Brand-new Factory OEM DCCV from us! - JaguarClimateControl.com

 

You may well be right, Aholbro1 regarding the coolant being a questionable blend. While my car seems to have been quite well maintained, it came with no service records at all (I am trying to be kind to any future owner by keeping a ridiculously detailed log of all maintenance I do). So I have no idea what the real status of the coolant is. It could even be 9 years old, or a right-royal mix. Another reason for me to do a proper flush next summer, I think.

 

Regarding Wuzupez's question regarding the part number for the 2007 STR DCCV - I believe it is the same as for the non-supercharged 4.2.

 

A little update in case someone is tempted to follow this procedure:

I have done 3600 km now since doing the repair, including a 2000 km round trip over a long weekend. I have had no problems whatsoever. I even managed to re-install the engine covers with no drama or fouling from the new hoses.

A close look at the attached photo reveals a bit of staining from coolant at the front of the motor, which is not from my heater repair - the water pump has a slight weep. The next job!

 

So, I reckon after doing over 20000 km I can safely assume using hoses to bypass the heater pipes is a viable proceedure. There has been no leakage from any of my joints and the hoses are showing no signs of being heat-affected.

Having said that, I am not implying this was the end of my 'water woes'.

Since I have owned the car I have also replaced the heater solenoids (described above), replaced the 'o' ring in the auxiliary water pump, replaced the water pump, and replaced the water rail (otherwise known as the thermostat housing). Finally, finally, finally my engine bay is free of that horrible pink staining and the sickly smell. The thing which I found hard to believe was that, while just about everything was weaping, the car wasn't really going through much water (yet!).

 

I find Amazon and EBay are about the cheapest for DCCV's.

Remember there are only 5 outlet and 3 outlet DCCV's. These two variations cover ALL the V-8 and 6 cylinder Lincoln LS and Jaguar S Types. It appears the XF has also carried this on but I am not 100% sure.
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G'day JagV8,

I was trolling around and found this post, which was my very first one upon joining the forum.

Just thought I would let you know we have now passed the five-year point since I did this job, so I think I can safely assume it can handle the pressure!