Spark, no run!

sportfire1961 · Post by **sportfire1961** » Tue Sep 13, 2005 8:38 pm

Help!, I have a sportfire that I can't make run, the carb has been rebuilt, it is getting spark , yet I pull and pull and am getting nowhere, Any suggestions on making it run like a deere?

harleysportster · Post by **harleysportster** » Tue Sep 13, 2005 9:13 pm

Check the exhaust for a blockage. Next try squirting premix fuel into the carb using a spray bottle set to a fine mist. If the engine starts and dies, the carb still needs cleaned. If the engine has the original crank seals, more than likely the seals are bad allowing the fuel mixture to be pushed out the seals. Check and see if the crankshaft is wet around the seal area, if so, the seals are bad preventing the transfer of the fuel mixture from the carb to the cylinder.

bob15 · Post by **bob15** » Tue Sep 13, 2005 9:45 pm

If the sled runs by putting gas through the carb or even a small amount down both plug holes, you might also check to see if the fuel pump is good. Also make sure the pulse line is attached to the engine and fuel pump and it isn't cracked or has a hole in it. Don't use clear hose for the pulse tube because it can collapse. Use a fuel line hose which has braided cord in it. Make sure the pick-up tube in the tank is still there and the screen its't clogged. Might sound dumb, but do you have a manual fuel shut off valve (right hand side, by your foot)?

bob

JDFanPa · Post by **JDFanPa** » Wed Sep 14, 2005 1:13 am

You should do a compresion check before busting your hump to much and make sure your working with a sound motor. Like everyone said so far does the sled start on spray gas,starting fluid carb cleaner try spraying something in the carb and see if it fires hold the throttle open when you do this also. If it starts you know your not getting fuel. You say carb was rebuilt but when if it was last season and it sat with fuel in it you will need to clean the carb inlet needle. There is something that breaks down in the plastic gastanks that if it sits for awhile in the carb gums up the needle and wont let fuel through. I say this from experience I have to clean the carb on my sporty every season because of this hell its even gotten stuck after sitting for a month.

sportfire1961 · Post by **sportfire1961** » Wed Sep 14, 2005 9:27 pm

Hey thanks everyone, I tried the fuel spray idea and it worked , the engine ran until gas ran out, I am going to go thru the fuel system and it should be fine, again Thank You!! Sportfire1961.

harleysportster · Post by **harleysportster** » Thu Sep 15, 2005 5:21 pm

Check out this picture if the your engine uses a standard type mikuni carb.
Jet number 32 in the picture is often overlooked and is part of the low speed circuit in the carb. If clogged , the engine will not start.

sportfire1961 · Post by **sportfire1961** » Thu Sep 15, 2005 10:42 pm

Thank you harley for that exploded view of the carb, I've been looking for one on line and have had no luck. I'll be sure to check that jet , I checked the fuel line in the tank and the inlet screen was completely plugged up so I am going to clean the tank and clean and rebuild the carb. I also found that many of the fuel line connections were loose. I'm not sure how it was getting any fuel at all. Thanks again!

tipitup · Post by **tipitup** » Thu Sep 22, 2005 12:10 pm

Hey Harley, this one sounds familiar. I still haven't got mine running with the same problems, but not all is lost. This is more just an update for ya.