Jaguar

Questions and Answers from "All Experts"

Name: Eddie

Subject: 1987 xj6

Question: My car has been siting for about a year now. I went to start it it fired right up I decided to change wires, cap and button on it.After doing so it has not started since. I changed from bosch platinum to platinum+2. Thats the only thing different done to it. Now with the +2 i get no spark from the distributor to the plug. With the old plug i get a weak spark. Spark from the ignition coil and distributor has a good blue spark. BTW i also put a new ignition coil on also. What can be the reason for it not to fire up. Ive been told it could be the fuel pump. In which im not hearing that fuel pump humming noise at all. And someone also mentioned something about it may have jumped timing.

Answer: Hi Eddie,
The most likely problem with the fire up would be to recheck the firing order and position of the new wires as it is very easy to get them mixed up when installing in the cap.
Even though it should run on platinum plugs, I am not a fan of platinum plugs.
Since you lost spark you need to not leave any stone unturned meaning go back and test all of the new parts. A good test of a rotor button is to pull the coil wire out of the cap and with the cap off have someone spin the engine while you hold the coil wire about 1/8 th. of an inch from the center of the rotor. If a spark jumps, the rotor is bad. (yes, new rotors can be bad) Look at the "tooth" inside the rotor and confirm it is in the same position as the old one. Look at the carbon brush inside the dist. cap to see that it is in-tack and spring loaded. Put one of your new plugs on the end of the coil wire and spin the engine to see that you have a good blue spark.
 
As for the fuel pump, do this.
Undo the three wire clips on the front of the air filter and slide the nose cone forward out of the way and remove the airfilter canister. Turn the ignition key to the "ON" position and reach in the front of the airflow meter and open the flap door. As soon as you do this, you should hear the pump running and hear the fuel circulating through the rail and lines going back to the tank. That is a preliminary test of the fuel pump circuit.
Let me know what you get in these tests.
Howard

Name: ROBBIE SALMAN

Subject: 87 xjs12

Question: i have a 1987 jag v12 and the fan belt is very loose  causing the car to over heat how do i tighten the belt thanks Robbie

Answer: Hi Robbie,
The adjuster is easily accessible on top of the power steering pump on the drivers side. It should be obvious as it is a threaded adjusting rod (like the other belt adjusters) with a 9/16 wrench on the two nuts on either side of the block attached to the top of the power steering pump. Loosen the outside nut and run the inside nut so as to move the pump. Don't over tighten the belt or you can cause damage to the bearings in the power steering pump as well as the water pump bearings. The other belts are adjusted in the same manner. good luck.
Howard

Name: Bill

Subject: fuel tank switching valve

Question: I recently replaced the fuel tank switching valve with a new one, but I cannot seem to get it to switch tanks.  The switch is working because the return valves are opening, so I may either have it hooked up incorrectly or it is a bad valve.  Could you please remind me which way the hoses reconnect to the switch?  I think I have them correct, but I thought I wold make sure.  Any trouble shooting ideas?  Please let me know.  Thanks.

Answer: Hi Bill,
As for connecting it up wrong. The only thing you could do is turn it around since the two lines from the tanks are very stiff and will only go on the two ports that are in line with each other. If you were to hold it up as a "T" the fuel lines go on the two top arms of the "T" and the fuel pump goes on the bottom of the "T". That only leaves the possibility of turning it around. When the power if OFF of the valve, it should have a clear open connection between the pump and the LEFT tank. A preliminary test of the switching valve is to turn on the ignition and set the switch to the RIGHT tank and unplug the POWER wire to the valve. This only tells you the solenoid is working but will not tell you if you turned it around. Make temporary contact several times with the POWER wire and you should hear the valve click each time.
The system is designed so that no matter what item fails in the switching system of the three valves it will always run on the left tank. It takes power to all three valves to make it run on the right tank and not transfer fuel to the wrong tank. No matter which valve fails you can operate off of the LEFT tank.
Let me know,
Howard

Name: Bill

Subject: front door locks on XJ6

Question: I have a 1987 XJ6 on which the front door locks do not work - not even manually.  They do not work manually or by turning the key in the driver side door.  I can't figure out how to access them or what may be wrong.  The rear locks will work manually.  Any thoughts?

Answer: Hi Bill,
If they don't work manually then you need to correct that first before looking at the electric motors etc. You have to remove the inner door panels to access any part of them.
Can you lock them by pushing the lock lever forward while sitting in the car with the door closed?
Let me know,
Howard

Name: tonie

Subject: series 3 rear quarter light removal

Question: Howard- I got it out! If you have any tips for installation great, otherwise I'm OK,
thanks again, T.

Answer: Hi Tonie,
Are you talking about the bulb or the whole assembly? If you are talking about the bulb just spray a little WD-40 in the socket to make it push in and rotate easier.
Howard

Name: Tonie

Subject: series 3 rear quarter light removal

Question: I have done everything that the factory manual says and up to this point the
glass is slightly loose (or more accurately the framing around it is slightly loose)
but I still am not able to remove it. Perhaps I am being a bit too gentle? Any
ideas, tricks , tips greatly appreciated! Thank you for sharing your vast
knowledge with us!

Answer: First Tonie, what are you calling a "quarter Light"?
If you are talking about a "Side Marker" light it only has one small screw holding the lens on and it is not glass it is plastic. If you are talking about the chrome piece that the lens attaches to, it is held in place by two small nuts accessible by removing the tail light assembly. If this is not how your side marker light is held on then you don't have a series III Jag. The only other option is that someone has replaced the side marker lights with some other brand car's lights. Let me know,
Howard

Name: Bill

Subject: heater in 1987 XJ6

Question: The heater works in this car but seems kind of weak.  The windows steam up all of the time with quite a bit of moisture.  I live in an area with lots of rain and high humidity, but can something be done to increase the airflow of the heater fan?   Or is there perhaps something putting moisture into the heater air?  Please let me know your thoughts.  Thanks.

Answer: Hi Bill,
Yes, there can be moisture in the heating system. If it is coming from a leak in the heater core it will usually put moisture on the windshield and you can usually smell it. Other possibles are stopped up AC drain since the AC system runs when the heater is on. Also it is possible that the blend doors are not operating correctly and in the rain you are getting rain in from the fresh air intake into the car. As with any automatic AC/heat system they are complex and have several vacuum operated doors controlled by a rotating drum that opens and closes several vacuum valves depending on what is asked for. Another item is that there are two fans.
This system is difficult for a DIY to diagnose and repair and even difficult for an experienced mechanic with the manual to do.
My advice is first look for an experienced Jag AC/heater mechanic and if that is not possible, bite the bullet and purchase the factory series III service manual.
Howard

Name: Rick

Subject: 86 xj6 power door locks

Question: Hello, power door locks in-operable....checked the switch/solenoid in drivers door & it checked ok.
Haynes manual says there is ciruit breaker and a relay for the power locks & removed the drivers side & the passengers side under-dash panels, but cannot find either one [wire colors in Haynes do not match wires on under-dash relays].
Any Ideas? Where are the circuit breaker and relay for the power looks?
Thanks.

Answer: Hi Rick,
The ser. III XJ-6 had either solenoids or motors. The earlier cars had solenoids and the later had motors. The easy way to tell which you had was the sound. Each time you would lock the drivers door you would hear a loud "Clunk" from the trunk solenoid. If you had motors type(which I think you have) you would have heard nothing. (when they were working) Only the solenoid type had a "Lock Relay" and a "Unlock Relay" and a "Thermal Braker". The "Motor" type had no relay nor thermal braker. They did have an in-line fuse in the Aux fuse panel area up to vin # 470739 and a 15a fuse in the #17 fuse position from vin #470740 on. Each motor had only two wires which would lock in one polarity and unlock in the reverse polarity. (including the trunk lock) where as the earlier solenoid type could not unlock the trunk electrically.
The two systems were easy to ID by their appearence too. The solenoids were round and the motors were flat trapazoid shaped boxes. I hope this helped.
Howard