SUCCESS!!!!!!!!

Thanks a heapload to Brendan for pointing me to a known trouble spot.

I did as you suggested and starting measuring some resistance around the car. The chassis to block was indeed not making a good connection so against my better judgement, I jacked the car up on that one side in my driveway after blocking the hell out of the remaining three wheels on the ground. Got the strap off and wire brushed the strap and also took my angle grinder with sander disc and cleaned off the body where the strap goes.

Before I did that I was seeing 2 mega-ohms of resistance!! After the cleanup, I was seeing almost no resistance whatsoever.

As a quick test for anyone suffering a similar issue, I did something really simple to ID this as the issue. I took my jumper cables and grabbed a spot on the brake booster and the other end on the alternator bracket. This provided a temporary ground so I could measure with my meter.

Voltages all came up normal on the starter relay socket and just for a final test, I jumped in the car and quickly hit the starter with the ignition and it worked. I would not advise starting the vehicle like this but for a simple test to see if it worked, it was fine.

Just drove the car around for awhile to get all the fluids moving and to clean up the brake discs etc. Almost got caught out when I looked at the temp gauge and it was nearly pinned! Glad I was only a short distance away from the house and whipped it back up the driveway.

Now the real work begins as I determine all the BS things that are not working. Obviously, the twin electric fans are not working.........lol. There is also a lot of noise from the suspension in the rear. Lots of clunky type noises so I am thinking we need some suspension work.

All in all, I am so very happy that I found this forum as it made the difference in getting this old girl up and running again. I checked most of her electrical systems and almost everything works.

Next on my list is:
Getting Fans Running
Finishing Door(s) Repair and Restoration

Once that's accomplished I have a host of cosmetic and amenity items to deal with but thank you to everyone who has helped on this project so far. Couldn't have done it without you!!

Bernie

 

Nice one Bernie and kudos to Brendan for pointing you in the right direction.

Please be sure to come back to this thread with anything else so we can all chime in and hopefully help to make this thing happen.....

 

Ummm,

I'm not going anywhere......lol

We still have lots to do with this car so I think I will stick around for a while if you don't mind?

Bernie

 

Lol......waiting

 

Ok,

Two things I want to tackle tomorrow.

The fans are not working

The heater is not working
Electrically, the system all works but when I set the car to heat, it does not. Any input on this weird one would be helpful

Bernie

 

Sorry, I hit Thanks for the above post instead of Reply, but thanks for all your posts anyway as I'm bookmarking this thread for all your electrical information!

My 2 cents: probably a plugged heater core. If the cooling system has been poorly maintained, corrosion will definitely plug the heater core. I had to have mine replaced, flushing didn't do much, but it's worth a try to really flush it well, both forwards and back-flush. I would do it in this sequence: get the fans working. Then, chemical flush the cooling system, do a really good rinse (probably multiple rinse-and-fill's), then flush the heater core. Replace the thermostat. Refill with coolant of choice. If still not enough heat, replace the heater core.

Which coolant to use? This car will do very well with regular green IAT coolant , but you need to replace every 2 years. Or you can use a HOAT coolant like Zerex G-05, which is what I used. This will last 4-5 years. In your climate I'd replace after 4 years. You can also use any "universal" coolant but I'm always a bit skeptical of these, as you can't tell if they have the corrosion inhibitor 2-EHA that caused all the issues with Dex-Cool OAT coolant. I'm really not a fan of Dex-Cool for that reason alone. But I digress.

My previous 97 XJ6 had a pretty anemic heater but I never flushed or replaced the heater core. My XJR with it's new heater core gives quick and plentiful heat.

 

Oh, it's such a pleasure to hear of progress, of problems solved once and for all, right here! Especially when they are solved at minimal cost. I admit I'm pretty excited that the car is running now!

So Bernie, let's make sure that engine is getting properly cooled! You may need a new thermostat (possibly stuck closed) and coolant, perhaps a test of the cooling fan switch (in the lower left radiator) and fan relays (again). The cooling fans should always be running with key on. These items go right along with a flush of the system and heater core. Minimal expense here for a DIY.

It is ironic that the engine has too much heat and the heater in the cabin doesn't have enough!

The heater core is fed by an electric pump with a separate valve. They are located below the brake booster, connected with all that plumbing you've seen down there.

Congratulations on your progress so far!

 

A water-flush was all that my heater core required to return to life, but see Motorcarman's post about filling only the core with flush solution and letting it sit overnight if you have greater clogging: Post # 2

https://www.jaguarforums.com/forum/x...winter-102192/

 

Thanks lads.

Seems to be one of those common Jag issues that heater core.

Today I am going to focus on finding out whats up with the fans and then move on from there.

Will update as soon as I have a direction.

Cheers
Bernie

 

I'd guess to check the electric heat pump first to make sure it's "whirring" and the "clunking" is more then likely the upper shock mounts, they seem to last about 60k or so before they deteriorate and need replacing.

 

well good luck with it....having had a few Chinese scooters myself i can tell you unequivocally that you got the better of the deal. i was going to rx...the interstate which i just got but looks like you bit the bullet . I think you made the right decision re the battery.

as for the loose key in cylinder/ignition, although mine was a 85 xj6....i rode mine for years with a similar looseness....and never had a problem starting the car. good luck again.

 

maybe a start for your fan troubleshooting:

https://www.jaguarforums.com/forum/x...-104419/page2/

 

So basically he was saying that the thermostat stuck closed which caused the car to overheat and the fans to not work? I guess that means the thermal trigger for the fans is located on the radiator someplace?

I noticed today that this car does not have the jumper for continuous run of the fans. I did the jumper myself and the fans run. I guess that it is the low-speed setting with the jumper correct?

Haven't gotten to pulling the relay yet to test it but I did put 12V to each fan and they both work and the jumper runs them on the continuous cycle so that's a small step forward.

Now about the heater:

I found the heater switch in the engine bay and tested it by putting 12V directly to it and it does work. I then tested its electrical socket and an old friend showed up. With car running and heater turned off, I am getting 12V to one side of the pin and nothing on the other. With the heater turned on to full, that pin produces only 6V. Sounds like maybe a ground issue but when I test the negative side of the electrical connector to body ground, I am not seeing any resistance.

Also, I have not found or heard an electric pump running for the coolant. Honestly, I need to take a better look for that.

Could this lead to a grounding issue with the HVAC controller in the car or to the AC module? Does anyone know where those items are specifically grounded to? I am researching through the electrical manual but maybe someone can point it out quickly for me.

Here is a picture of the electrical bridge I did for the fans and also the coolant switch I was testing.





One more curious little pic for you to see:
I guess the rubber bushings for the top of the radiator are missing? The radiator moves back and forth and the condensor for the AC is also not feeling secure. I am assuming the Jags are supposed to have rubber bushings in place to prevent the radiators from slopping around?



Cheers
Bernie

 

Yes don't drive it much until you get those installed. Rockauto.com has them. X300's have a thing about shedding the lower condenser bushes - I have a condenser with a hole rubbed in it that can testify. Little bit tricky to get the upper cond. Bushes in place when replacing the upper rads, but take your time and double- check before you put the grill back on. Order 4 of each, you'll want new lowers even if they are still there.


Didn't really follow that fan link I posted; just remembered it had popped up recently & thought it may help. These thermostats usually stick open & the V8's closed, but I guess not EVERY one follows the "rules"


That is a solenoid H-Valve you've been fiddling with. My understanding is that the electric pump should come on when the valve is opened, don't think you'll hear it, I've had mine off and run it on the bench; a quiet lil bugger. There's pics and how-to's on changing the brushes, do a search if you dig into it. I can probably find it again if you have trouble searching it out. Pump is mounted on fender very near or maybe under the valve.

 

I went out and did a quick check for the pump and found it under the area where the solenoid was.

First thing I did was take my trusty little 12V bike battery and put juice directly to it. Its either the quietest pump ever or its dead......lol. The answer is its dead. Doesn't even make a little sparky on the battery when I touch the lead on. The good news is that I am measuring 12V at the power supply to it so that's just a matter of repairing or replacing the pump. Still have no idea why the solenoid power supply is only sending 6V though? The electrical manual says the grounds for both of these is against the firewall inside the engine bay. I have already popped and cleaned both gangs so the grounds directly to the devices is good. Maybe its the AC module? Going to poke around at that tomorrow.

So this is just the pump for the heater core correct?

Found a supplier for those radiator bushings on ebay and they sell a pack of four. I guess the lowers and uppers are the same part. Haven't seen what the condenser needs yet though, ran out of good light and time.

First thing I need to do is replace the battery now as the car wouldn't start tonight until I gave it a boost. It was odd because it never even tried to start? It just did nothing like what it was originally doing before cleaning up the ground. As soon as I put the booster to the battery, the trunk lights got brighter and then it started no problem. Does this car have a system whereby if the amperage is too low it bypasses the starter? Just wondering.

Cheers and thanks for all the info!

Bernie

 

Hey Richard,

Thank you for the kudos.
SO I think the thermostat is ok. My car did not have the low speed mod so I made it myself (see pic below). The air blowing back from the fans is warm so I think that's ok for the moment. I have discovered that the heater pump is indeed dead so that's coming off which gives me the excuse to drain, flush the system, put in new thermostat and get all the other cooling related bits sorted out of which there appears to be a few

In due time I will get all the niggly little items sorted but its making it so much easier to be able to access the wealth of knowledge of these cars from this awesome forum. I hope all my repairs as I bring this old girl back to life will serve as an aid to others as they attempt to do the same thing. A collected knowledge base right here on this forum !

 

Ive had clicks and slow cranks in the past.


Btw, your sig line says 1986; you're mending a '96 now, though aren't you?


Pump is finicky about polarity -I thought it should run backwards if reversed but it thought otherwise. Pretty pricey lil units, but a brush change looks easy enough.

 

Oops,

Yes my mistake.

Thanks.

 

Bernie, this thread addresses your heat pump problem, an alternative pump and detailed instructions on brush replacement on stock pump.

https://www.jaguarforums.com/forum/x...ot-heat-84596/

 

I found the heater switch in the engine bay and tested it by putting 12V directly to it and it does work. I then tested its electrical socket and an old friend showed up. With car running and heater turned off, I am getting 12V to one side of the pin and nothing on the other. With the heater turned on to full, that pin produces only 6V. Sounds like maybe a ground issue but when I test the negative side of the electrical connector to body ground, I am not seeing any resistance.

Could this lead to a grounding issue with the HVAC controller in the car or to the AC module? Does anyone know where those items are specifically grounded to? I am researching through the electrical manual but maybe someone can point it out quickly for me.


Hi Bernie

The ground for the pump and solenoid valve are on the LH bulkhead beside the ABS module. The one in the second picture in my previous post.

The ground for the HVAC control unit is in the cabin on the gearbox tunnel. See attached. It could be either or both of those ground studs.

One other thing to consider with that 6V reading is that it could be a PWM (Pulse Width Modulated) signal. I doubt it given the age of the car, but it is common for that type of signal on a solenoid in later cars. If your Multimeter has a Duty Cycle option have a look at what reading that gives.

Also, I noticed from your picture that you have the white connector unplugged. Ideally your should keep this plugged in and take readings by 'back probing' (stop sniggering!) the connector.