Bad Gas

I have a '90 SN that I have not started in 2 years. Ran great 2 summers ago. I failed to put fuel stabilizer in the tank back then. Now the engine turns over but won't start. I just syphoned all the gas out of the tank and put in new premium gas. Still won't start, but I did get a single backfire this morning, so I am encouraged (I think). There is probably old fuel left in the fuel lines and fuel filter. How long do you think it will take for the fresh gas to reach the carb? Any other suggestions (I'm a rookie)? THanks in advance!

Rebuild the carb now, otherwise you are just going to have problems. With the gas setting it that long everything is gummed up and varnised over so the needle and seat, metering blocks, accel pump and everything else need to be replaced and/or cleaned in a tank of carb cleaner. A can of gumout isn't goint to get the job done. Also check the cap and rotor odds are they're rusted up and need replaced as well. Flush the fuel lines and replace the filters as suggested by mackwrench and have the carb rebuilt and you will save a lot of time and be back on the water trouble free. Also you need to replace the impeller and change the oil and filter as well.

I rebuilt my Holley just this spring with a kit from Summit Racing, cheaper than other places and it's the same kit. I am only reasonably handy in spurts. Take your time, take notes (pictures are great if you have a digital camera or go get them developed ). The kit has a exploded view of all the parts. You can do it, and if it don't work then call the mechanic.

Jim:

If you attempt the rebuild yourself, make sure you note the position of the idle mixture screws and to a lesser extend the idle speed screw. Simply count turns to lightly seated and after rebuild adjust to same setting and you should be good to go.

Does a '90 SN have ignition points? If so, sand them clean before doing anything else. After two years, they can rust over and cause a no spark condition...happen to me this year on my '77 after sitting the winter.

You might try giving the engine a shot of starting fluid to see if it will fire. If not, look for no spark. If yes, get that old fuel out of the lines. Make sure it is not flooded with old fuel. See if it runs ok (after you get it to fire) before rebuilding the carb, you may get lucky. I also would try running two cans of BG 44K (fuel system cleaner) in one full tank. This stuff is amazing.

The idle circuits are most suseptible to gum and varnish. See if the cleaner helps. By idling up, you are simply bypassing the idle circuits and opening the throttle plates...for the cleaner to work, you must get the fuel to flow through the idle circuits. Briefly closing the choke on a warm engine until it almost stalls (with throttle plates fully closed) forces a higher vacuum through the idle circuit which can help clear them out.