I have two questions...

One simple (but not steering related) - Can you advise best spark plug to put in my 1968 Jag 240? Currently has Champion N5C but I'm not sure if that's the best, and not easy to find. Searching for it brings up many others, but I figured I'd accelerate the learning curve and not risk a mistake buy reaching out for your thoughts first.

Second one... when driving it recently, the steering wheel has become loose... like it can move it around within a small circle at the wheel (up, down, and around)... it almost seems like something like a collar or spacer dropped out near the steering wheel itself, because all the slop is at the wheel end... but I didn't see anything drop out or where it would go. Perplexing.

 

I'm going to leave spark plug options to others. Many have opinions other than original.

Is the steering wheel in/out adjustment collar with the knurled **** on it behind the wheel on the column done up tight?

 

Back in day when I was running my Mk2 (more than three decades ago), spark plugs were a big topic for me, partly because my car seemed to eat them and partly because I'd spent several years studying spark ignition. The standard Champion Plugs did their job and lasted the recommended service intervals. The Bosch plugs of those days were terrible. I'd start to hear an unsteadiness in the idle of the engine after a few hundred miles. That might be why Bosch have done such a huge amount of work developing modern high tech plugs. I had a set of Golden Lodge. They were brilliant, needling little cleaning and no adjustment. Although Lodge was an old British make, the easiest source were Alfa Romeo dealers.
My reply has been limited to technology of the day. Members with running cars may have a lot to add on using modern plug deigns.

 

Yep ~ I only ran Golden Lodge plugs in the six Alfas I owned over time. Enjoyed them. But they were the days of lead erosion of electrodes. Plug life with modern materials & unleaded gas is huge as long as they spend enough time running in the self cleaning range you never have to touch them.

What heat range plugs did you run in the Mk2 in Champion or NGK nomenclature?

 

The Champion were whatever the Jaguar Mk2 handbook indicated for 8:1 c.r. The Bosch would have been as recommended by Bosch or as claimed by them to be equivalent to the Champions. For the Golden Lodge, I don't remember. I think they were the same as I used in my Alfetta 2000 GTV. I never experimented with heat ranges as the peformance of the both Champion and Golden Lodge seemed to be insensitive between north of England commuting and high speed on the German autobahn and Italian autostrada.

It's strange looking back, but Bosch spark plugs had an almost laughable reputation when they were trying to establish themselves. I met some of their engineers, they were nice people and very persistent in their efforts.

 

Ref. Steering, there are 2 felt bushes holding the inner (rotating) column central inside the outer (static) column (top & bottom). These bushes get pressed down & wear, resulting in the inner column floating. May also find as the inner column floats & contacts the outer column, the horn goes off!!!
Fix is to buy 2 nylon bushes, remove the steering column & grease / fit the new bushes.
To remove the column, release the inner column at the articulated joint on the other side of the bulkhead (under bonnet - I had to remove the carbs to get to it!!!), release the jubilee clip at the bottom of the footwell, then remove the 2 bolts under the dash bolting the upper section of the outer column to the frame. All then slides out as a single unit, & strip it down on a bench. (Also need to disconnect the purple horn wire from the column before removal). Had to do same last month (see post "Beep ...Beep" - sounds arduous job, but is actually quite easy.

 

Similar problem with the steering which I had. As Simon has said it was the felt bushes in mine which had deteriorated to a point that when I took the column apart the dust which was all that was left of the bushes fell out the bottom. New Nylon bushes and the column is tight again. My only problem since is that every now and then the nylon bushes get dry and start to squeak when you turn the wheel to a liberal coating of grease is required or the occasional squirt of silicone grease down the shaft.

 

For my steering bushing I used a strip of felt pad- the kind you might stick to the bottom of a chair or table leg. It was very close to the right thickness so I used a razor blade to just shave it a bit, then a few drops of oil and slipped it in.
For what its worth, I used to buy the more expensive plugs but never really felt I got anything for it. Lately Ive gone back to the basic Champion copper or whatever was the original and now feel like there is a difference- a better idle etc.

 

I am using NGK BPR5ES in a 3.8 and they seem to work well. I am also running a Ford EDIS distributorless ignition with coilpacks, so considerably more energy than an original points system could produce.

 

If it's bushes ~ these replaced felt:




Old felt. Barratts can supply the two different thicknesses of felt but you have to cut your own.