oil at the base of each plug

[mahogany101]

try and follow me here as i am not up on the correct terms under the bonnet. my mk1 runs as smooth as butter, starts good to. but on a long or short run oil collects around the base of each plug. obviously the longer i leave it the more oil collects. ive developed a way to soak it up, because i have been told to leave it if its running ok as it would be an expensive job. one more thing it is definatley not running down as i have changed all gaskets, it is coming up past the plugs from the inside of the engine. any advice guys.
howard.

[SegaSceptre]

Sparks or Core?

[Gary Knight]

Hi, My Sceptre also has oil at the base of each plug. Shortly after I had the car I had to have the engine rebuilt. I did know the engine was worn when I bought the car as the oil pressure was very low, sure sign of a worn engine. The normal pressure on a new engine hot is 55lbs. sq. in. [3.8kg.cm sq.] at 50mph. If the oil pressure gauge shows roughly this it might be slightly less, and will drop when idling you are probably ok. I had to have a new bottom half for my engine as that part being cast iron [the top half is aluminium] cracked when the crankshaft broke inside! But I don't think the garage replaced the rings on the pistons, or if they did they must have used standard size rings, which if the bores are worn of course won't be large enough to stop a little oil getting past and into the combustion chambers. This might account for the oil at the base of each plug, although my car doesn't seem to burn any oil which is strange. Of course when you buy new plugs they have a ring at the bottom but I think this is maybe to stop gases escaping rather than oil. Anyway the upshot is that there is probably nothing to worry about as long as your car is running alright, it might be one of those things you have to put up with. Maybe someone else on the site, or even Segasceptre might come up with other ideas, or if you know a friendly garage or mechanic they might be able to help. My car seemed to run fine for at least 15 years with this problem, it's been off the road now for about 9 years, as you know. But last time it was started about 3 or 4 months ago the engine ran fine. Hope all this helps reassure you not to worry too much.
Regards, Gary.

[aubrey]

Hi Gary, The simple answer to you question is that all the MK1 and 2 cars suffer the same problem to a lesser or greater degree. The tube where the spark plug screws is in fact just that, when originally fitted the hole/aperture was coated with a shellac type sealant and the tubes were then heated and pressed in, with time, heat and engine pressure the seal breaks down and oil finds its way out of the joint and runs down into the tube and sits around the plug. Rootes found that it was cheaper to produce the heads without this and cast the MK3 heads solid and just drilled and tapped the spark plug hole instead. Yes it is a pain and spoils the look of a nice clean engine, I don’t let it build up too much and my MK1 and 2, its been like it for 20 years on my MK2 it runs a sweet as a nut. Finally Ive not known anyone cure it yet, its just one of the pleasures of running a Classic. Aubrey

[Gary Knight]

Thanks Aubrey, all these years of Humber ownership and I never knew that! I'm sure mahogany101 will be pleased too, that there's nothing to worry about.
Regards, Gary.