Yeah, fixing the heat issue is foremost. If not fixed, any other issues
will be irrelevant.


1. Rodding out a core is old tech and tough. The tanks re removed. Imagine a skinny hack saw blade. That is the rod. it is jammed into
each tube and pushed and pulled, cutting out old deposits. The tubes
may not survive intact. Solder to fix the leaks, mebbe. More on the way, almost certain.


2. If the clogging is moderate or less, a boil out might extend the core life a bit.


3. But, face facts, just how old is that brass core. How many times
has it heat cycled? It's life is finite....


Carl

 

OK.

At the risk of crossing any line in the sand, here goes.

Removing that radiator is NOT that hard, especially with the bonnet off. Time consuming,YES, frustrating, YES, blood letting, HELL YES.

With that bonnet off, I would estimate 4 hours TOPS to get that radiator out, and that would be for a first timer with a decent dose of common sense.

My first one took all damn day, now I get them out inside the hour and the bonnet stays ON.

My concern also extends to the "shop" involved. Unless they know/understand these V12 Beasts, they may make a mess of it, basically coz "time = money", and that money is yours. Then the issue of the "will be required" hoses and belts whilst ALL that room is available. Can/will they do it, and do it properly?.

Orangeblossom ON HERE, had a HUGE thread on that task a short while back, and it may be worth reading that before committing to strangers messing with your Pride and Joy.

We are not permitted to drive a car with the bonnet off, maybe your "powers that be" are different.

 

Howdy all! I figure I'd better give you all an update.

My father and I did indeed pull the radiator ourselves. It was actually not as hard a job as I thought it would be. However, when we did finally get that sucker out, I was shocked by what I saw! I think we may have found part of our problem...



Anyway, I took it to the radiator shop, and I should have it back by Thursday.

 

WELL DONE, and I mean that.

That is 60% of your issues, now the internals of that radiator will be the other 40%.

My sugestion:

Whilst that sucker is out, and the room is huge, I would be replacing the hoses, and belts, and wash down the front of that engine.

 

Alrighty... Got the new one in, and took it for a drive.

Some interesting bugs came up...

First off, either the engine is running REALLY cold, or the something's wrong with the sensor. The needle never moved. Always on C.

I turned on the heat, and it is blowing hot air. Is the temp of the air a good gauge to judge how hot the engine is? And the heatsoak issue is still there, but a little lesser so.

Also, during the day, my horn stopped working, as did the lights that come on when the headlights come on. Any fuses I should look for?

Thanks in advance.

 

Under the hood, on the drivers side of the car, there is a small fuse block on the inner fender. I believe the first fuse in the block towards the front has the horn circuit running thru it. These also are for the lights. Also the relays for the headlights and horn relay is mounted just forward of this, could you have possibly bothered the connections while working on the radiator?

 

If the heater is getting hot, the engine is warmed up. Also, try touching the top hoses from the engine to the rad. Most likely your sensor wire is broken or detached. It goes to a small sensor on the US passenger side on the rear end of the thermostat casting (where the RHS top hose comes from). taking te temperature of the top hose is a good way to get an engine temp.


You could try as a test, ignition on, just touching he connector to earth quickly, while someone watches the gauge.
Greg

 

I checked the fuses, all were good. I forgot to specify, that when I turn on the headlights, they come on, but the dash cluster lights do not.

Could a faulty ground cause these issues?

 

Do not have my manuals in front of me right now, but there is another fuse block under the drivers side dash that should have a diagram on it showing which fuse operates the dash lights. Check there. Also if you car has Lucas fuses, be aware that their amp ratings are different.
Faulty grounds can cause this and a lot of other bugs in your car.
I just spent close to a week (when I had time) going over my 87 checking and cleaning all the earth wires.

Johnny

 

The lighting switch feeds Main fuse panel #7. This feeds the rheostat which feeds the instrument panel illumination, center switches ill, and fiber optic ill.

First try exercising the rheostat and see if it wakes up. If you still are dark then jump the rheostat out and see if it's gone bad.

The horn is fed through the horn relay by fuse #1 in the headlight fuse panel. Suspiciously, this wire is spliced to feed the cooling fan.

The wiring diagram for the XJS begins at page 57.
http://www.mediafire.com/view/?n8w2quhzgbv66uu

 

Uh, where is the rheostat?

 

Just about by your knee when you are in the driver's seat. A round flat knob on the lower black dash trim.
Greg

 

Hmm, it's not that. It "seems" to work.

Okay, I was tired when I posted last night. Here's a list of the issues.

Horn doesn't work.

Dash lighting may work, not sure.

Headlights work, but when I flip them to high beams the High Beam indicator light on the dash does not light up.

Coolant Temp Sensor doesn't really seem to be working, even though I just replaced it. It was working before I put the radiator in, but it's not now.

Hopefully this clears some things up. I have checked all the fuses, and they seem to be in order.

Thanks,
Peter

 

Hi Ardsley

As Grant mentioned, I recently had to have a New Re-Cored Radiator, as the one I took out was damaged by a flying stone.

So I filled it up with a mixture of 50/50 Antifreeze and De-Ionised Water, as I live in a Hard Water Area.

After fitting new Brake Pipes and doing other Stuff, I decided to 'Bleed the Radiator' as I wanted things perfect in case we got a Frost.

As Grant already mentioned, there are lots of different ways to do this but this is the way I did mine.

Over the Top of the Radiator, is the Closing Panel with the Pipes on Top of it, which lead to a Banjo Bolt, which on my 1990 is 16mm.



Banjo Bolt and Washers going into the Rad


You have to be really Careful, while you are doing this, so you don't dislodge or else lose one of those Copper Washers as you might not have a Spare one to replace it with.





This is the Banjo Bolt with the Holes that Grant was talking about that tends to get Blocked up with Rust and Crud.

My Secret Weapon is a Syringe that the GF uses for Icing Cup Cakes.

The reason it is Secret, is because if the GF finds out what I've been using it for, She is probably going to Kill me!



Icing Syringe for Cup Cakes

At great personal risk to myself, I 'borrowed it' to Fill with Antifreeze.



Having taken the Brave Pills, I filled it with Antifreeze.


After Filling with Antifreeze, I used it to fill up the part of the Rad that usually gets some sort of Air Lock.





It took about 12 Syringe Fulls to Top the Rad right up, although it 'appeared' to be full when I first put the Antifreeze in.



Putting the Last drop in!


Full to the Brim and time to put the 'Banjo Bolt' back in.

 

If your Engine is Still Overheating, the reason could be the Fan Clutch, which seem to be a lot cheaper in the USA than we have to pay in the UK.

This is a Viscous Fan Clutch, which initially doesn't Spin the Fan very Fast but as the Fan Clutch gets warmer, it gets a grip on the Fan.

At which point it Spins it really Fast and while the Car isn't moving, should be kicking up a Storm under the Car, as in more than enough to flatten grass!

Also when the Car is Hot and you switch the Engine off, then the Fan should come to a dead Stop but if it keeps Spinning, then you've got a problem and the Fan Clutch will need replacing, which is good practice anyway if you fit a New or Re-cored Rad.

Also Check the Fan for 'Stress Cracks' Any sign of Cracking, Change the Fan as a Cracked Fan can disintegrate and not only take out your Rad but also knock a great big dent in your Bonnet/Hood.

When the Engine is Hot and you Switch it off, the Auxiliary Electric Fan Should cut in and keep on running until the Thermostat gets to the right Temp and cuts it out.

Does all of this happen on your Car.

 

OB, was there a particular reason you bled at the banjo rather than the bleed screw?

 

Not really, except the Banjo Bolt on my Car is a known 16mm so no quirky size to try and find a Spanner for and I can also Check the Banjo Bolt, to make sure those holes are still clear and not getting Blocked up.

 

Whew???


Glycol is very poisonous to mammals. Glycol tinged icing on the
cup cakes??? I'd arrange for that thing to vanish and be quietly replaced. Another meaning for double jepordy (sp).


Carl

 

Hi Carl

Cup Cakes or Rad?

Needs must when the Devil Rides out, so a bit of a 'no brainer'

 

Welp, just thought I'd finish what I started.

Turns out, I believe the issue with the horns, lights and the gauges was infact, my battery was low.

I have a junky old Pull-A-Part battery, and it has been going bad, so I pulled it out charged it and hey presto!, everything works! And the best part? The temp gauge seems to be happily parked in the middle of the N once warmed up.

Alas, I am ready to move on, so I have decided to sell the car.

I really do love this car, but I'm not one that likes to get attached... The longer I have them, the hard it is to let them go. (I'm dead serious )

So anyway, thank you all for your help in fixing this car!

P.S. Here's the ad: 1989 Jaguar XJS V12 LOW MILES!!!

Finally, Merry Christmas!!!