Rocker shaft thickness?

[Harris]

Dear Sir,

Restarting my RILEY after winter period, I discover some water mix with oil in the sump….So, I decide to make a deep enquire on that problem ( I have it before but not that much.) So, under complete recondition are : radiator, water pump, cylinder head, guides, valves, all gaskets, lap tappets and so on….

When I buy the car, I discover 2 different rocker shaft…Now I have same model on each side ( Sprite model I think, see picture I buy from Blue Diamond long time ago.)

Some of my rockers are damaged, have re shaped roughly and thickness different on most of them…..

Are you able to confirm what was original thickness of that rocker section ? ( mine are between 4.7 and 6 mm, measured in center , thicker section of the oval.)

Do I have still enough material to reshape them properly ?

Do you have any suggestion to solve my problem ?

I thank you per advance for your help.

Bst Rgds,

Jacques DUCRU
[e-mail]

[silverstreak]

You do not say which model, but the rockers suggest late 1930 onwards, and Sprite says Pre war. 12/4?
Water in the oil won't be due to radiator, valves, guides etc. Water pump is unlikely unless the carbon seal is leaking and the drain hole is blocked.
head gasket, cylinder head studs leaking round the thread in the block, a common problem caused by corrosion, the studs go into the water jacket. cylinder head possibly, check the plug thread, cracked block face, I've had water coming through the cylinder bore where pitted on a +60 bore. leaking center main bearing if you have a 6 cylinder. From that lot I would first suspect the head studs, visible water may be showing round the nuts in the rocker covers if you havn't run it recently. If you are lucky, new stud with thread sealant. or just pour in a leak sealant!
I wont comment on the amount of metal needed to reprofile the rockers.

[falconriley]

Those are post-war RMA rockers, as they have a lock nut on the adjusting screw and a strengthening rib across the back. The pre-war type have a pinch bolt and no rib. The postwar are much more bester, and yours look to need refacing. Not sure what the thickness should be but they can be hard faced and reground. I doubt yours have enough hardness depth left to just reface them.
Matthew

[alanv]

Bonjour Jacques,
If you haven`t found the part that you require please contact me Alan [e-mail] as I have a Merlin and loads of spares.
Regards Alan

[silverstreak]

Jacques and Alan, If Jacques is still interested in bits after a year make sure you are both talking about the same engine size. Merlins came as 12/4 and 9.
I think that the pinch bolt rocker was superseded in the late 30's. Certainly all 16 of mine are the later design. I doubt that it matters operationally and the thickness, within reason, can be taken up by the adjuster as long as the thread doesn't start to foul on the push rod. Pinch bolt are easier to adjust!