Just a footnote for those that are interested on what turned out to be the cause of the plug fouling. I have posted this to assist other owners, as there have been several 'plug fouling' threads on BH of late.
It turns out that the vertical cylinder which was giving me the most grief was running far too rich on the idle circuit. What I suspect was occuring was the plug was getting too much fuel and 'drowning' somewhat, once it started to foul and misfire then the problem was just compounded, the spark completely being lost.
As for the horizontal cylinder, this was simply set too lean, causing the poping back etc. When you are advised to fully seat the idle circuit screw, then back out 1.5 turns as a benchmark, take care! Mine needed nearly 2 full turns out before it was happy to tick over evenly. 1.5 out was way too lean.
What I have also done is replaced the Shell V-Power 98 octaine with BP Premium 95 octaine. A pair of new plugs (B7HS), carb balance and it is actually running very well.
I won't be so quick to blame the ignition in the future...
Weak Spark - Roundcase
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Crashfangio
- Mariana
- Posts: 35
- Joined: Fri Aug 15, 2008 6:48 pm
- Location: Melbourne Australia
When dismantling carbs, I always check if the two idle-mixture screws are the same, something that is often overlooked.
Screws of VHB are visible different , on comparison that is.
Makes a huge difference when setting up carbs.
Another check i make is the # of the jets themselfs and I mean measuring them.
It can be done with some "right" sized needle, to make comparison between different jets.
I certainly can't see the difference between a 55 or a 65 idle jet, but your engine certainly will notice.
cu
ducadini
Screws of VHB are visible different , on comparison that is.
Makes a huge difference when setting up carbs.
Another check i make is the # of the jets themselfs and I mean measuring them.
It can be done with some "right" sized needle, to make comparison between different jets.
I certainly can't see the difference between a 55 or a 65 idle jet, but your engine certainly will notice.
cu
ducadini
Nego i ricordi peggiori
Richiamo i migliori pensieri
Richiamo i migliori pensieri
I could be wrong here, I have never had the oportunity to check it out for myself but I was told that silicone leads are a no no. I beleive they have resistance built into them as supressors. I recntly changed the coils in my SS and was advised to use wire leads. If memory serves I ended up getting my leads from a mower shop cause the auto store did`nt have any.