Camshaft endfloat adjustment

[David Morris]

Hi there,

Just thought I would mention that I had an annoying intermittent squeal from our Javelin engine, that I had convinced myself was due to fan belt mis-alignment. I had assumed this was because the water pump and its pulley wheel is difficult to keep properly aligned, due to the very, shall we say, 'flexible' mountings. [ I am being kind to Jowett's here...perhaps not one of their best design moments? ]

However, after taking off the fan belt to prove this, the squeal remained, so this was more serious! Investigation into the adjustment of the camshaft endfloat adjuster on the late-type front timing cover showed that the locking nut had worked itself loose or at least it was not particularily tight, and the adjusting peg had enough clockwise movement to 'pick up' on the end of the camshaft and was probably trying to screw itself into even tighter contact with the end of the camshaft! Hence the squeal!

I have now reset the adjuster as per the book and thankfully the squeal has gone. However, I reckon I was close to having the camshaft locking-up on the adjuster, with what would have been serious consequences!

It might be worth making sure your locking nut here is tight, to avoid any problems! I have now added this to my growing list of nuts and bolts on the Javelin that need frequent checking for tightness, to avoid future trouble! They are, for me at least, all the steering box mountings, all the front suspension mountings around the outer ends of the torsion bars, the long cross bolt that carries the brake and clutch pedal bearings and the rear axle outer half shaft nuts. I am sure others will have their favourites as well, but all these have given me trouble in the past and have left their personal scars! They all get a 'tweak' when I am under the car doing routine maintenance! I would be grateful for any other personal favourites, to avoid future problems!!

All the best,

David

[David Morris]

Hi there,

Just a closing note about that squeal! Yes, the camshaft adjustment nut kept loosening and a drop of Loctite solved that!

Why the squeal was intermittant will remain a mystery?

However, in the end the squeal turned out to be a leaking exhaust valve! This was proved on the run home from Wakefield, as DCB246 got slower and slower!. We finally made it home, probably more on two cylinders than 4! We changed the off-side head for a refurbished one and not only did we lose the squeal but she is running better than ever!

So, if you hear a squeal don't assume it is metal to metal, but it might be the beginning of a leaking valve!

All the best,

David