Running Rich

[samk]

Hi All,

Recently I've come to the conclusion that my engine is running a bit rich. The plugs were quite sooty when I changed them and theres always a whiff of petrol when the vans started up and initially idling (not inside cab)

I've searched the wiki and forum but havent found any info easily decipherable for a mechanical noob. Basically, what i'd like to know is what are the negative effects of running rich and how easy is it to alter ( a simple screw adjustment?) I'm a bit nervous about tweaking it as my understanding is that its not good to run an air cooled engine even slightly lean.

oh, and would it cause me to burn more fuel? It feels like i've been burning it even quicker than normal lately.

2ltr air cooled by the way

cheers,

sam

[Red Westie]

Recently I've come to the conclusion that my engine is running a bit rich. The plugs were quite sooty when I changed them and theres always a whiff of petrol when the vans started up and initially idling

Lets not draw too many conclusions here......this is 30 year old carburettor technology, mechanical cold start enrichment devices that are crude at best. We all get very used to modern vehicles and their 'seamless' cold start cycles where we almost cannot tell they are running on 'choke'.
These old gals would chug and cough, and blow out ten bells of crap for the first 3 to 5 minutes on cold start and THIS WAS JUST NORMAL for the era and fueling devices fitted at that time.
As for your plugs....only make a judgement based on examination after a 15 mile plus run when the engine has been well and truely 'up to temperature' for 15 minutes or more.

Martin

[samk]

Thanks Martin,

So, if I replace the plugs and go for a longish run and THEN check, this should give me a better idea of how the engines running, roughly speaking?

[Red Westie]

Yes mate.....best checked after returning from a longish run if you want an accurate idea of how things are running.

[kevtherev]

If you were a complete petrol head, you could run the engine at 65 mph for two miles, switch off, coast into the hard shoulder then pull a plug.

[samk]

cool, thanks guys, I'll be doing this soon.

[jason k]

better rich than lean on an Aircooled motor