84 XJ6 S3 Spring Check-Up
 

1984 XJ6 S3 Spring Check-Up (174K miles) 3-28-2019

1. Vacuum at Idle: 16 In-Hg steady @ 800 RPM; 18 in-Hg @ 1000-1200 RPM; rechecked after timing adjustment, no change

2. Fuel Pressure at cold start position on fuel rail: 30 PSI @ 800 RPM; 28-29 PSI @ 1200 RPM. With Vacuum line off regulator, went to 37-38 PSI.
(regulator is few years old; a Bosch ~ 2.5 BAR on data plate (36 PSI)

3. Oil temperature cold: 55+ PSI @ 850 RPM, 60+ PSI @ 1200 RPM. Oil temperature hot: 34 PSI at 750 RPM, 55 PSI @ 1200 RPM

4. Exhaust Back pressure test (removed O2 sensor). 0-1/2 PSI @ idle, 1 to 1-1/2 PSI @ 2000 RPM

5. Installed new O2 sensor (3 years old and probably ok, just too complicated to confirm)

6. Installed new Fuel filter (4 years old), old filter looked clean when emptied

7. Test ride at 72 degrees OAT, A/C on: Temp gauge; 89-90 degrees on freeway, 91-92 degrees in town

8. Trip computer: went from 16 to 95 MPG, when closing throttle from 60 MPH (A/C off)

9. Trip computer: 19 MPG at 2550 RPM and 68 MPH steady cruise (C/C on)(A/C off)

10. Found Spare tire down to 10 PSI, back up to 36 PSI

11. Annoying squeak turned out to be edge of bonnet resting on bolts attaching fender stabilizers. Added self-sticking buffers to bonnet above bolt heads.

12. New rear springs and shocks, original shock leaking, fluid puddle on garage floor

13. Battery = 12.4 Volts before starting; 820 RPM idle = 14.1 Volts main buss

14. Ignition timing (vacuum capped off at distributor ) @ 820 RPM = 14* BTDC , adjusted to 17* degrees; reset idle RPM

I was sensing a loss of acceleration between 2000 and 3000 rpm. It could be from too many trips in my Wife’s 5 speed-series-3 BMW (another classic straight six) or, I am reading too many {hard starting-poor running posts} on the few remaining “non-GM engine” XJ6s????

At this rate, an XJ6s with an XK engine, may be a collector car yet !!! Can you see a bevy of XJ6s being trailer-ed to the car shows behind Land Rovers, or even Teslas, with Jay Leno announcing best in show XJ6, or a new season of Top Gear being dedicated to XJ6s??? No...No…No… sorry - what was I thinking!!! - just way too many mushrooms on the pizza last night. Drive them until your wife says!!! It’s you or the Jaguar, one of you, or both must go.

God Bless Jaguar Owners

I love how you meticulously check everything. That's how you properly work with a 35 year old car.

Husband wouldn't Dare make that kind of threat! He knows what I would choose!! LOLOL

I have my own Spring Tune-up going here. New starter is only the beginning, but I'll do a better job posting later.
(';')

That's how you properly work with a 35 year old car. Thanks, can you imagine the Bill if this was done by the Jag dealer??? Older Jaguars and retirement work well together. Rgds David