'80 LF overheating?

notasledguy · Post by **notasledguy** » Mon Jan 15, 2007 5:04 pm

Hello, I'm new to this site and have read alot of the postings and have some ideas but could use some advice. Was given a 1980 liquifire and went through (what I thought was) everything. Pistons,rings,bearings,seals,carbs,fuelpump,fuel lines& filter, oil lines & filter,pulse line. Sled did not have an airbox on it & until reading some posts on this site did not think it was quite that big of a deal! Problem-although my temp. gage does not work it seems to be getting so hot that fuel is evaporating before it can be ignited in cylinder. Starts on 2 pulls cold. Runs great in mid-upper 30's (outside temp) for about 30 minutes and dies.Try to start choke off/choke on/WOT 100-150pulls & nothing but put,put,put. Pull plugs, getting good spark but plugs are dry. Fuel is misting out back of carbs but don't seem to be making it into cylinders. Dump some fuel into cylinder, put in plugs and it'll run until fuel is gone but won't restart on own until cold (at least 1 hour). Any ideas?

sledchad · Post by **sledchad** » Mon Jan 15, 2007 8:55 pm

Check your pulse line and make sure there isnt a hairline crack of some sort. Then check your fuel pump, sounds like ur starving for fuel. You can get rebuild kits for the pump cheap like 5 dollers. Try that and let us know.

notasledguy · Post by **notasledguy** » Tue Jan 16, 2007 8:25 pm

Thanks for your reply, but have already replaced/rebuilt fuel pump,carbs,pulse line & fuel lines. I do have an air screw that looks like it has been over tightenend and might be bent. Do these air screws tighten into replacable seats? Any ideas on where I could find some new ones? Thanks again!

sledchad · Post by **sledchad** » Wed Jan 17, 2007 12:51 am

If your talking about the fuel/air mixture screw yes i would screw it out and check it. The tips should be straight with a flush end. Screw it all the way back in then 1.5 turns back out. You said you replaced the seals?..are you sure you put them in correctly? I saw new ones installed not straight and cause problems. Double check your carbs. Check the float height. Make sure none of your jets are plugged. Oh..get an airbox..very important. Let us know on your progress.

Mean Green · Post by **Mean Green** » Wed Jan 17, 2007 9:09 pm

If the temp guage doesn't work and you suspect high engine temps, have you checked the thermostat? 25 year old thermostat could be the problem, or some joker may have used stop-leak in it at one point and clogged up your radiator core partially. Old sleds are like a box of chocolates. Ya never know what yer gonna get into.

Tracy