Just rebuilt my twin solex pdsit carbs and fitted them yesterday and ran the engine for about 10-15 mins, ran great, nice and smooth but black smoke out the exhaust, obviously the carbs need tuning which i'm going to do once my ste bk synchrometer arrives. I started the engine again today and it ran like a bag of poo, which i kind of expected, so i removed the spark plugs to clean them so i would be starting with clean plugs when i balance the carbs and i found that 3 of them where jet black as expected but the other one was clean(ish) looking and had a slight shine to it. Now i'm wondering how 2 spark plugs running off the same carb can be different? The engine is a 2.0l type 4 with hydraulic tappets, could the valve on this cylinder be out?
Perhaps that one hasn't been firing at all or rarely. I've just set up 3 sets of these carbs from scratch so if you need any advice ask away. You need to be quite methodical!
The confusing thing is that when i got the van it was running rough, so the first thing i did was remove the plugs and i found the same thing, except that(bosch) plug didn't look like it had fired at all, so i put in an old spark plug i had lying around and started the engine and it did run 100% better, so then i thought that it must just have been a dead plug. So then i decided i would rebuild the carbs, i removed carbs rebuilt them and now refitted them and also fitted the new ngk plugs. Surely i can't have had 2 dodgy plugs in the same cylinder? think i will change the plug leads, although they do look fairly new.
checked the tappet gaps? If they're ok, then do a compression test... How new are the leads and dizzy cap?
Whats the best way to adjust the valve clearances? was thinking of maybe doing it with the engine running? as that way the hydraulic lifters will be fully pumped up? otherwise i worry that they may bleed down and then the adjustment would be out.
It would have been rude not to plug them in, you don't always know what people will bring along. Most people between booking a service and turning up a few days later will have thought of (and brought with them) enough other stuff they just aren't going to get round to doing to keep me busy for days. "oh, and while you're at it could you just have a quick look at these bungy cords I have to use to keep the door closed - I was fiddling with the catch, pushed the.... oh and do you do MOT's?"
As Paul says, they don't have a gap, you'd have to jab them in pretty bloomin quick and you'd get covered it oil.
That's an upright engine... try doing that on a boxer engine and you're getting covered in oil... plus that engine you're adjusting the pivot point, not the actual tappet
