Not exactly cars, as this relates to a 1969 Nuffield 4/25 tractor fitted with 1.5L BMC diesel, but I hope this isn't too far OT. Gave the old girl a thorough service last weekend which included changing the glow (heater) plugs as 1 was not working.
3 came out fine. The 4th, which was the one not working, has broken and left 1/2 inch of the stem in the cylinder head. I left the remains of the plug out and ran the engine for 30 minutes, with the radiator muffled, in the hope that compression might just spit it out. No such luck. The broken bit of the glow plug is about 1/8th inch dia. and is buried about 2 inches within the head.Am I stuck with having to remove the head? Don't really want to do this if I can avoid it, but little tractor is a bad starter with only 3 working glowplugs. For now I have squirted penetrating oil into the orifice and replaced the remains of the broken plug. This only finger tight in the hope that the broken stem may yet be spat out under compression. Any thoughts or advice please?
Many thanks
Nick.