Uberoo Posted July 5, 2011 Share Posted July 5, 2011 I have an Ea81 in my offroad toy.It has SPFI.Lately it seems to be jumping the timing at the distributor.Car will run fine and then all of the sudden it started running on two cylinders and backfiring through the intake.Check timing and it was way off.So readjust timing.ran for 2 minutes then back to two cylinders firing and backfiring through intake.I readjusted the timing again and now I haven't gotten it to start yet.I got it to "run" by pulling it with another vehicle.It would "run" only when it was gear.I could rev the engine up about 500 rpm from where it was being towed at but it would die if I took it out of gear. The teeth on the distributor are fine,the roll pin holding the distributor gear to the disty shaft is fine,the rotor is on tight,and the gear that drives the distributor is fine. Is the engine fixable or do I need to go on the hunt for another engine? Quote Link to comment Share on other sites More sharing options...
brumby420 Posted July 5, 2011 Share Posted July 5, 2011 I have an Ea81 in my offroad toy.It has SPFI.Lately it seems to be jumping the timing at the distributor.Car will run fine and then all of the sudden it started running on two cylinders and backfiring through the intake.Check timing and it was way off.So readjust timing.ran for 2 minutes then back to two cylinders firing and backfiring through intake.I readjusted the timing again and now I haven't gotten it to start yet.I got it to "run" by pulling it with another vehicle.It would "run" only when it was gear.I could rev the engine up about 500 rpm from where it was being towed at but it would die if I took it out of gear. The teeth on the distributor are fine,the roll pin holding the distributor gear to the disty shaft is fine,the rotor is on tight,and the gear that drives the distributor is fine. Is the engine fixable or do I need to go on the hunt for another engine? Do you think its possible that the timing chain got stretched or something like that. When i had the motor it never was in perfect time but it ran good enough. If i remember correctly it would run best when the disty was advanced as far as it would go. Quote Link to comment Share on other sites More sharing options...
NoahDL88 Posted July 5, 2011 Share Posted July 5, 2011 the screw on the rotor could have fallen out and that may be messing up your timing. If the rotor is flopping around in there that could be your problem. Quote Link to comment Share on other sites More sharing options...
ihscout54 Posted July 5, 2011 Share Posted July 5, 2011 What is your timing "jumping" too when it acts up? Make sure to plug in the green connectors befor you set the timing, remember its 20 deg since its SPFI. The EA81 doesnt have a timing chain, so jumping timing would be a bit of a trick. Your sure the gear/pin on the distributor is good and tight? Keep in mind that was one of the tricky parts of the SPFI swap. Quote Link to comment Share on other sites More sharing options...
Turbone Posted July 5, 2011 Share Posted July 5, 2011 Could be a cracked disty cap. Quote Link to comment Share on other sites More sharing options...
Uberoo Posted July 5, 2011 Author Share Posted July 5, 2011 (edited) the screw in the rotor is tight. cap is fine and the pin holding the distributor gear in place in fine if I grab the disty gear and the rotor and can move them maybe 1-2* as far as how much its jumping, anywhere from 90* out to 270* out. Edited July 5, 2011 by Uberoo Quote Link to comment Share on other sites More sharing options...
Turbone Posted July 5, 2011 Share Posted July 5, 2011 Remove the valve cover and check the gear on the cam. Quote Link to comment Share on other sites More sharing options...
Uberoo Posted July 5, 2011 Author Share Posted July 5, 2011 I will pull the valve cover off when I get a chance and look at the gear.Right now the subi is at my friends house some 45 miles away because that is where it was towed to. Is there a roll pin in the cam gear that might have sheared? Quote Link to comment Share on other sites More sharing options...
Turbone Posted July 5, 2011 Share Posted July 5, 2011 Wait, I just realized its a EA81. I'm rechecking... The drive gear is on the end of the crank, behind the seal. It will be a pita to check..... Quote Link to comment Share on other sites More sharing options...
Uberoo Posted July 5, 2011 Author Share Posted July 5, 2011 when I was inspecting the distributor I looked at the drive gear down the hole where the disty went.It looked good.I even put the disty in without a cap just to see if the rotor was spinning...everything looks good. is the drive gear an integral part of the cam or was it pressed on or held on with a roll pin? Im just lost how a purely mechanical engine like a EA81 that has everything driven by gears and pushrods could have the timing slip. Quote Link to comment Share on other sites More sharing options...
NoahDL88 Posted July 5, 2011 Share Posted July 5, 2011 If my memory serves, the timing gear off the Cam/Crank (forget which one) is part of the shaft, and shouldn't spin on its own. Check the gear on your distributor, as well as the rotor again, make sure the screw is locked into the flat spot at the top. If your bolts holding in the disty aren't tight that could also cause your timing to slip. Quote Link to comment Share on other sites More sharing options...
Crazyeights Posted July 6, 2011 Share Posted July 6, 2011 I just pulled an EA81 down last week. The distributor drive gear is on the front end of the crank. Remove the pulley and the seal and it should slide right out. I think the gear is a soft metal like aluminum so it could be worn. The beveled side goes in towards the engine. Good Luck! Quote Link to comment Share on other sites More sharing options...
nickolai Posted July 6, 2011 Share Posted July 6, 2011 The disty drive gear slides onto the the crankshaft right behind the front main seal. There's a small woodruff key on the crankshaft that keeps the gear in the right spot. When you check the gear, make sure this woodruff key is in place, and that the inside of the disty drive gear is in good shape. Best of luck. Nick Quote Link to comment Share on other sites More sharing options...
Idasho Posted July 6, 2011 Share Posted July 6, 2011 I will pull the valve cover off when I get a chance and look at the gear.Right now the subi is at my friends house some 45 miles away because that is where it was towed to. Is there a roll pin in the cam gear that might have sheared? 45 miles from lewiston? Where is the car now? Quote Link to comment Share on other sites More sharing options...
Uberoo Posted July 6, 2011 Author Share Posted July 6, 2011 car is in ruebins ID Quote Link to comment Share on other sites More sharing options...
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