THE INTERNATIONAL JAGUAR 'S'-TYPE REGISTER FORUM

Warning ~ Fuse values


Remember that Lucas fuse values of 35 & 50 amp etc are old British 1 second blow standard.

Fuses you buy today unless you order specially are American Carry Current rating.

In modern fuse values you should select a fuse of approx half the value of the Lucas rating shown in Jaguar Manuals.

e.g. Lucas Horn fuse = 50 Amps. In modern US rated glass fuses you should fit 25 to 30 amp.

Failure to do this could cause a fire in our car's wiring in case of a short.

My car 3.4 ltr chassis IB 4722 DN was passed off production 6th August 1965. It has full synchromesh gearbox and overdrive, with an inline fuse protecting the overdrive circuit.

The original in line harness fuse for the overdrive is located on the left side of the steering column, under the dash, just about above the clutch pedal. Often the continuity of the fuse arrangement is broken by the end contacts of the in line fuse holder and not just a burnt fuse. I use the term burnt fuse rather than blown fuse, as these fuses tend to burn out with heat.

Mine bought by my parents in Feb 1966 with 13K miles. Always a west coast car and garaged, Zero rust. Now with 170,000 miles. Never "restored" but did get a comprehensive engine and mechanical overhaul 2 years ago. Runs and looks like a new car. In the 1960s era cars in the USA could be year model updated if still in dealer inventory when model year changed around September'October of the year. That is why the VIN has a prefix of J-65.

Definitely won't have the inline fuse November 64. While I replaced all harnesses my car was built early 1966. SA did not start building them until early '66 at CDA East London. I call mine a '65 because somehow it was registered on our system Dec 65. Mine was No 4 off of the local production line here at CDA. It is something I have never been able to resolve. Maybe it was registered as a pre build Demo as the CKD kits were already in SA. It was delivered straight to the Johannesburg dealer & never saw the coast again until I brought it finished down to Cape Town. Was bought new by a Doctor from that inland dealer at 5800 ft above sea level. Why it was rust free. It was always garaged at altitude in very dry air.

The S Type Register confirms this.

It's a November 1964 build car but designated as a 1965 per the VIN J-65 P1B76415DN One hundred and five VINs, i believe, after the change over to the full syncho gearbox. So the inline OD fuse must have started later.

A pleasure. A '64 won't have a fuse fitted. The engagement current is 20 Amps. The holding current is 1 to 1.5 Amps

BTW the pin in the hole setting is not ideal either. One needs to play around a little to ensure no slip of the cone clutch.

Glyn, That makes sense. Many, many decades ago we burned out a replacement solenoid as the installer did not understand the importance of correct adjustment. Apparently, my November 1964 build car does not have the inline fuse. I only saw it on my large color wall poster of the wiring diagram which is apparently for later cars. Thanks for your reply.

It's an inline fuse usually in a red holder to protect the solenoid should it not come out of engagement current to holding current. Early cars did not have them so you burnt out the solenoids.

John I have an Auto box so can't help with specifics but from my knowledge of working with my own wiring loom apart from the radio I cannot recall any inline fuses. All my fuses were/are situated behind the dash panel and all the wiring is centred around these eight fuses. Having said that looking at the aluminium plaque in the front of the fuse box there is no mention of the O/D.

So does anyone know where the inline fuse for the overdrive is located?