Hitchcocks Forum

Been for another ride and what seems a leak - on the l/h side of cylinder head - with some oil on the fins at the level of the spark plug, so above the cylinder head joint. Noticeable on the side opposite to the pushrods.

There seems to be oil on the alu cylinder head on the fins at the level of the spark plug/decompresser/stud at the side. No oil seems to be coming from the oil pipes (and they are on the other side) - the head joint looks 'shiny' but oil isn't seemingly coming from there...and if it was seems odd it would go upwards and make it damp there.

The rocker cover caps aren't leaking either (or damp).

I can't see a 'crack' in the head anywhere....could it come from the stud near the spark plug - is that a normal source of a leak? If so - any suggestions if it is the stud?

M

Fairly normal source of a leak, not quite sure why seems to happen even with composite gasket

Hi guys-------- I had a Bullet 65 a few years back that developed a slow, persistent leak from the same spot---------- turned out to be an off-set, internal casting at that point --just by the valve area---and a very small amount of porosity allowing oil through..

my enfield leaks round the head area if its not serious ie oil on your cloths id leave well alone stops the engine going rusty

I had a similar problem with my Sixty-5. It turned out to be a porous cylinder head casting, which weeped oil, ever so slightly, between two of the fins. It took a while to pinpoint and the precise location was around one of the cylinder head stud tunnels. Someone on the American Enfield site had experienced the same thing, and offered two suggestions for a cure. The first was to apply heat-resistant exhaust paint to the area, which I found only worked for a short while. The second - and successful - suggestion was a tiny splodge of "JB Weld" (a magic compound in a tube, widely available on Ebay) which I applied with a cotton bud after thoroughly cleaning the area with acetone (nail varnish remover). It is a very discreet repair, not noticable deep in the fins and it is has been totally dry now for over a year (2500km).

Barry, JB Weld magic in a tube

Hi guys------ BARRY N, yes--that was it !!Just down that blasted tunnel and inaccessible as well... Come on guys, there's nothing "magic" about a two-pack, epoxy resin glue....We call it ARALDITE in the UK and it does exactly the same job !!... BARRY N has "Cottoned-On" to the real secret----sorry about that poor pun there, BARRY--------- and that is ABSOLUTE CLEANLINESS before applying...I was able to Peen the area closed with a long, thin chisel, then used the epoxy resin to form a secondary seal over that....As per BARRY though it was "Job done"....PS}---- If you happen to have the head off, and access to a machine shop, you can open out the tunnel and have an interference-fit aluminium tube made and fitted in along with some LOCTITE sealant (like a mini-liner)....I'm doing a similar thing to a "Cheapie" Aluminium cylinder from our hosts that has a porosity inclusion down one of the push-rod tunnels....