small amount of oil on the spark plug thread?

[Tony Starks]

So, my current shed is an EP90 Starlet with the 2E carb'd engine.

And if I don't get the revs and clutch absolutely spot on it's very sluggish on pull away and hills. A guy at work recommended plugs and leads and it was better for a short time (3/4 days) but it slowly crept back to it's old ways.

I noticed a small amount of oil on the plug threads when I took the old ones and I checked the new ones today and they're the same.

Does anyone have any ideas? And is it a hard job for someone with limited mechanical knowledge?

about the limit of my expertise so far is changing the oil, filter plugs & leads and am just about to change the starter over for a new one.

Cheers

Alex

Edit for a pic

Edited by Tony Starks on Wednesday 18th February 08:32

[CrutyRammers]

The oil doesn't look like anything problematic to me, engines are oily things. Not familiar with that engine but I've had plug wells filled with oil to no ill effect. A bit on the threads doesn't matter.

However, there seems to be a white deposite on the ends of the plugs, which doesn't look normal to me at all. Plugs can tell you about how combustion is in the cylinder, normally they should be grey to light brown after a run, not white and dusty.

A quick google suggests that you might be seeing ash deposits due to excess oil in the cylinder comming down worn valve stem seals. Or a coolant leak. Or the wrong grade of plug. Did the previous plugs look the same?

When it's sluggish, does it misfire, or just lack power?

If changing the plugs improved things, it would point to a spark problem, but that normally manifests as a very obvious misfire (usually under load) and black, oily plug ends.

If you don't have a misfire and it's just generally sluggish, off the top of my head, it could be:
- ignition timing out
- fueling issue
- cam timing out

If you clean the plugs, do things improve again?
Is there any oil smoke from the exhaust on start-up?

[PositronicRay]

The right hand plug looks fouled to me.

[Martin350]

The colour may be slightly decieving in the photo but I'd say that it could be running a little lean.

If it is running lean, be careful, I would drive it a bit gently until I had it checked out with an exhaust gas analizer.

Is the engine standard?

[andyiley]

Plugs look just fine, except the right hand one, was it like that (oily/mucky) when it came out, or was that from handling it with oily hands?

The oil on the threads is NOTHING to worry about, it will be from an old rocker cover gasket & is on no consequence.

I am not familiar with an EP90 starlet, (I thought EP 90 was a gear oil) so can't make specific suggestions, but I would recommend a good service as a starting point, that will check timing & fuel mixtures & other necessary starting points, see what happens then.

[Tony Starks]

There is a misfire if I floor it, but generally it just bogs down then slowly builds up speed. If I drive sensibly then I can overcome all this.

The plugs I took out were the same condition.

[CrutyRammers]

Ah, sounds like a spark problem then. Either the ignition system is failing somewhere and the appearance of the plugs is a symptom of that, or what's happening to the plugs is caused by something else and that is causing the spark to fail.

You've changed the leads and plugs so assuming the plugs are correctly gapped, it isn't them. That leaves the coils or coil really.

I'd get the fueling and timing checked, then look at changing the coils.

[andyiley]

I think it sounds more like a carb issue to me, possibly a worn needle jet, had something that sounds like your issue a few years ago on a Fiat Uno.