How to resurrect a mini?

I'm hoping you guys can help me out. I have a '74 mini that has been sitting for about 2 years. I put a starter in it (the reason it sat). The fuel in the tank smelled like pain thinner so I drained the tank, blew the line clear, cleaned the bowl of the carb of bad gas and the very little sediment that was there. Then I put about 2.5 gallons in the tank, primed the lines (compressed air in the tank till fuel came out of the line at the carb), put some fuel in the bowl and cranked her over. It kinda fired once, maybe ran for 2 seconds. That's all I've got out of it.
The plugs are wet after I try to start it 5 or 6 times and the one plug I tried it on had a orange spark jump across the gap.
I don't know much about carbs, even less about SU's. Could there be a needle stuck somewhere? What can/should I do to get it started. I have a buyer waiting and I need the money/garage space. Before I parked it (in the garage) I drove it all the time, it was a great car, almost my DD actually.
I sure appreciate your help.

Check that the carb slide goes up an down smoothly and check that you've got oil in the turret - if you don't the piston will go up too quickly when there's a vacuum.

SUs in general are pretty simple so they don't tend to go really bad after the car stood around for a little while.

Other than that, either dry out (on a gas stove or with a small propane torch) the spark plugs or replace them. For some reason they never seem to work that well after they've got wet.

Thanks Tim. I unscrewed the black knob on the top of the carb because I thought I remembered there should be ATF under there. There was. When I went to put it back in there was resistance to me pushing it back down. Does that mean "the carb slides up and down"? How do I check that it moves up and down? I think I'll pick up some plugs tomorrow.

The resistance in there is normal if you've got oil in there.

What I was referring to is that you try to lift up the piston inside the SU by poking your finger into the carb from the airbox if you can get at it that way, otherwise you might have to take the carb off.

One other thing that might be worth checking is to ensure that the needle valve in the float chamber actually closes when the chamber is full. I just noticed that my BMW doesn't do that after it stood for the winter and it's now overflowing the float bowl. If yours doesn't close properly you'll end up with way too much fuel in the engine.

The carb piston should push up with some resistance (the ATF), and then drop cleanly and quickly all the way down from its own weight when released. Take the dome off the carb and clean up the insides.

If there's still resistance to dropping, it's usually that the piston needle is making contact with the jet (the tube it slides into), but that doesn't happen just from sitting.

I'll check that the piston is moving, thanks. I was wondering if the needle could be stuck so I'll pull the top of the bowl off tomorrow and have a look-see. I thought that resistance was normal, but I'm not sure if it dropped cleanly from it's own weight. I kinda had to give it a gentle push.
Thanks again. is there a decent site that has good general info about the SU? I've heard they are very simple, once you know how they work.

This page may help: http://www.sucarb.co.uk/Technical.aspx

I just went out to the garage to check the piston. Yes, it moves up with a little resistance and falls back down with little resistance. I'm either not getting a good enough spark, or it's over-fueling then? I'm suspecting the carb, but we'll see after I spin 4 new piston return springs in there
The thing is though, I'd hate to put good plugs in only to foul them up....

My guess would be more like overfuelling, but it might just be that the electrics didn't like waking up in time. Hence my comment about drying out the plugs with a propane torch or on a gas stove, if it starts then you can throw new plugs in.

I agree. I hate to bug you Tim, but where do I go next? When I had the float off the bowl it seemed to move properly, but I didn't really check.
I really do appreciate your help.

Can you hook up a "fake" fuel feed to the carb? Ie, pull the fuel hose of the carb, then put a piece of hose on that's hooked up to a funnel and get someone to pour down a little fuel into the carb?

That way you can play with the float and see if it really shuts off the fuel supply at some point. BTW, is the float plastic or brass?

Hmmm, I'll try that. The float was plastic.

I was asking re the float because some brass floats are soldered and eventually you can get fuel in them, which means that they won't float properly.

With a plastic float you might want to check if it floats in a bowl/glass of gas or water. Some of them will absorb liquids over time and get heavier.

All that said, IME it's often the float needle that's causing the problems, not the float itself.

If there was a problem with the float, gas would be dripping out the overflow vent on the bowl cover.

There an old (but true) saying that 90% of fuel problems turn out to be ignition. Clean the point sna check the gap. Swap on a new condensor. I bet it'll run.

Take the filter off and pour a bit of fuel into the carbs. If the engine fires, then continue to mess with the carbs. If it does not, then move over to the electrical side.

Points can be all kind of messed up just sitting for two years. Same with the wires. Corrosion on the points and eteriorated wires as seen by your orange spark. you want a nice blue spark.

Ok, I've spent some time farting around with it, a little here, a little there.
The spark was kinda weak so I put in a MSD Blaster coil cuz it was laying around. The spark is much sparkier now. The plugs would still be soaked in fuel after 10-15 seconds of cranking, though it did sorta catch once or twice. So I decided to remove the top part to look at the needle. It was clean, looked new in fact. But, after seeing how the carb is put together I did some more poking around, specifically checking the piston travel after putting it back together again.
I noticed that the piston moves up, maybe 1/4" before I feel the damping resistance that the ATF provides. Is that correct, the ATF dampens the up-travel of the piston? Anyway, could I simple need to add a bit of AFT?