Saving Old Seagulls

Both my century motors ran like shit at the Tasmanian meet. Fuel was only a month or two old mixed from BP 95 octane. Both would only run with the coke nearly fully closed regardless of mixture adjustment.
A month on and I've just got around to running them in the tank to check, same fuel same deal.
Drained both carbs and tanks and mixed some fresh fuel and away they went, sort of. It was an ethanol mix fuel standard unleaded, don't know if that makes much matter....
One ran reasonably and when I snuck my finger fractionally over the comp hole it ran like a dream, my understanding was that it was lean so raised the needle to compensate. Raising the needle made no difference but slightly blocking the compensator did. Stupid seagull!
Checked the compensator on the other motor which is brass and the hole is slightly smaller, swaped it, went had lunch, tried it again and it would only fire a few turns then stop. Not much compression, head leaking, removed head and found a visible leak from corrosion. Must of been the residual engine heat that kept it going before lunch anyway will machine head and try again. I don't know if the impending leak was causing the mixture problem or not.
The other compensator i have is black plastic and the hole is probably a couple of mm bigger.

Normally when I tune I use the choke blade to slowly cut off air to see if there is any change in revs when it gets starved of air so I can tell if the mixture is about right.

Do any of you know of this difference in compensator hole size, does it matter? Or should adjusting mixture take care of the difference?

I had a similar problem with a century,the head gasket was leaking so refitted it with gasket sealant, also cleaned the carb thoroughly and cleaned the points and gave all around the point housing a good clean, also replaced the plug cap on the lead and now all is good.
I wouldn't use the ethanol mix not even for fire starting,it is rubbish,I quite often use old fuel with little to no problems.

Mmmm did wonder about the ethanol mix, doesnt even smell like petrol. Might try some other. The 95 I used was a premium fuel so it could have dodgy shit in it which may play havock with two stroke oil. I use it in my Range Rover too and have noticed coming into winter that starting is different, maybe they stuff round with the stuff in different seasons.
Petrol is not what it used to be...
Everything else is done and tip top so it's only fuel issues.

You say that the fuel mix was OLD E mix?

E fuel loves water so do not use it........does not smell like proper fuel? Full of water even just from ambient conditions over time.

Use real fuel and enjoy as normal.

If your carb has clear airways etc, not a problem.

E10 is not available in Perth so we do not have this problem?

Just a thought

Regards

B

Collector Inspector wrote:You say that the fuel mix was OLD E mix?

No the stuff I had trouble with was BP 95.
New stuff I mixed was E mix and they ran ok but I'm not going to use anymore.

I wouldn't us that stuff -- you will end up getting towed

skyetoyman wrote:I wouldn't us that stuff -- you will end up getting towed

I wouldn't mind getting towed if there were someone to tow me, it's when there isn't it worries me more