Howdy, next upgrade project about to begin. I have a 1985 Sovereign XJ6 and want an aftermarket Radiator and Alternator. My current Alternator is only putting out 13.2 volts at idle and I plan to put a nice audio system, but will need a better alternator first. My Radiator is the OEM stock and after almost 30 years it may need replacing.

 

Most guys needding more oooomph from the alternator use an AC Delco unit. Johns Cars in Dallas sells a converson kit/bracket kit. I think its the 'CS130' model Delco alternator that is most popular....but I'm a little foggy on that. Other use the Bosch 115amp from the XJS V12....but I think you're own your own for pulleys and brackets.

I've heard the aluminum radiator from a 2000-ish Mustang V8 is almost a perfect drop-in and works great. I'll try to find the details if nobody chimes in. Only about $200 as I recall.

The OEM radiaotors were really high grade.....costs quite a bit to recore them with a comparable quality core. Some of the aftermarket replacements for the Jag rads are good, others junk. 12-14 years ago a high grade non-Jaguar replacement was about $350.

Cheers
DD

 

I tried the Alternator Upgrade (GMalt) from John's Cars in my 1984 and I was not happy. I thought the original Lucas was not enough but the GMalt is worse, with similar sized pulleys and all. My XJ did not like it.

the original Lucas alternator was better, which might explain the reason Jaguar installed the Lucas and not a GM alternator in the Series 3 XJ-6, considering all the GM parts that Jaguar used in the XJ-6, from the Power Steering Pump to the Window Lift Motors.

the Bosch alternator from the XJ-12 is the better alternative. And don't throw away the original Lucas alternator. keep it as a spare. (OEM = Original Equipment).

if you need a different pulley, take the Bosch to an alternator shop and have them swap the pulley from the Lucas.

 

Jose:

Sorry that your Delco was less than expected. Lots of reasons other than quality that Jaguar selected a Lucas unit. A good Delco and a good Lucas are probably on par as to quality and performance. Trouble is a poorly rebuilt Delco is not a good answer.

My lump has a really big Delco that powers the GM stuff and the Jaguar stuff just fine.

Benefit: if a Delco goes duff in South Dakota, the local parts hluse can offer a replacement. A duff Lucas, only mebbe.

As to Jaguar radiators. I have a personal opinion that although of high quality, a bit short in hot climes. Great in the foggy, rainy and cool homeland.

But, a recore with a high quality modern core can fix that.

Aluminum vs brass? Lots of opinions here. All with strong points. I chose a four row modern cored brass radiator and it has performed flawlessly. Some say two or three rows are more efficient.

When my IHC Scour II brass radiator sprung a leak, a solder job fixed it. Now, the plastic tanks on alloy cores??? A fix. I suspect only one, a replacement. Throwaway vs fix. My voter is clear!!

So many radiator adventures over my decades of fussing with horseless carriages!!

Carl

 

Yup. 'Rebuilt' anything is an iffy proposition these days. I thinks odds are 50-50 at best when buying an off-the-shelf rebuilt alternator, starter, whatever. This reflects the quality of the rebuilding more then the quality of the original design.

The Lucas alternators were not sub-par in terms of quality. However, Jaguar often specified units that had just-barely-enough output to meet the demand. If you want more oooomph then you'll have to go to Bosch, GM, whatever.

Cheers
DD

 

Thanks guys for all the responses, I think you have me started with my shopping choices. I will come back and let you know what I purchased and how they are performing.

 

13.2 volts is a bit low buty where did you measure the voltage? It's best to measure it at the back of the alternator at the + lug while grounding to the alternator case. If you get a higher volatage there you may have restistance in the wiring which is typical for the age of the vehicle. Also check the engine ground too.

 

I thought anything higher than 12v is great if not "normal".

I agree about the Engine to Chassis Ground Strap, it should be "Maintained", as in Removed, Cleaned shiny, and the points where it contacts the chassis and engine/transmission should be very shiny too. This will allow electrons, neutrons, and protons to do their thing.

There are two other places to clean shiny, (and I am sure Doug and Carl will agree), there are two "Hot" Wiring Junction Posts located at the firewall/bulkhead, one on each side of the engine. All the Ring connectors and the Posts/Bolts themselves should be cleaned of any oxidation, and the Protective Rubber Boots should be in good condition.

there is a small Ground Strap mounted with a ˝" Bolt, located at the rear Top of the Cylinder Head (near the Battery) which should also be shiny-cleaned and checked after a few years.

the Radio itself has a giant Heavy Duty Ground Strap which you only see when removing the radio. One side of this giant strap is bolted to the transmission tunnel which you can't see unless the carpet is pulled.

 

Sure, with the engine off. :-)

You really want about 13.8 to 14.5 volts with the engine running.....that's sorta been the rule of thumb for some time.

Recently I replaced the alternator on my brother's Chevy and the instructions said to expect 13.8 to *15.1 volts*....which seems a bit high to me.

Agreed 100% on grounds and the firewall junction posts. All overlooked too often.

Cheers
DD