carb backfire/engine running backwards
i am stumped. i have a 80 4x4 truck. has the 20r with trd cam and 32/36 weber carb.the cam/timing chain is on (5 deg or 11:30 on cam degree). new distributer/cap/rotor.
the problem is sometimes it starts no problem and runns perfect. but the problem is sometimes it will crank then once i let off of the ign it will fire but run backwards (counter clockwise) for a second or 2. and white smoke will come out of the carb. when it does this it blows unburnt fuel up into the air filter ass.
i am frustrated as hell. please help also here is a link to a video of what it does when it runs backwards.

 

not sure why it would run sometimes but the problem sounds like you could have the distributor 180 degrees off.

 

that is what i thought but everything seems to be legit.
i will take some picts in a bit and post them, of the dist, crank/cam positoin, and try to video it better.

 

here are some picts of the dist, crank, and cam (the dot on the middle is where the cam key is).
now i have NO spark. i tested the igniter as per the FSM. coil tested good. so i am beat

 

I could be wrong, but I don't think that it could actually start rotating the correct way, run backwards for a couple seconds, and then run the correct way again. Seems like the engine would stall before that would happen.

 

sometimes it starts and runs fine.
but when it acts up, it will crank clockwise then as soon as i let off of the keys (turning it over) it will fire but go counterclockwise. like in the video.
it does not run clockwise (normal) then stop and go counter clockwise then back to clockwise.
it will crank clockwise then at the end of cranking it fires and runs counterclockwise for a second (like in the video) only a second- it will not stay running counterclockwise.

i think the problem must be in some loose wiring or bad wires

 

well i checked the pickup in the "new distributer" from checker and it is dead. no ohm reading at all. so i think that was my no spark issue. i am getting a new hopefully unbroken one.

 

Make sure your plug wires are connected correctly. Cross firing will cause backfiring out of the carb and can make the motor crank backwards.

 

thanks for the post juanpabloazul. they are hooked up to what the cap says
ok new dist. is in. started up fine. shut it off and now will not start again.
i set the timing to 8* with sub advance cut and with it uncut it is just off of the ledge (identical to the FSM for that truck).

****hooked up a plug to the #1 cyl plug wire and had someone turn the motor over. no spark at all (new dist, cap, rotor, coil and ign tessted good) then as soon as they let off of the ign switch(key inside cab) i would get one strong spark. so do you think it might be the resistor wire inline from the ign switch? or possibly the ign switch??
ANY ideas would be great, Harley.

here are some pict that i took for the other post on TN.



http://www.toyotanation.com/forum/sh...d.php?t=217863

 

anyone know where the Ignition Resistor wire is? i cant find it for the life of me. wanting to see what it looks like.
any sugg would be great

 

***THE WINNER IS IGNITION SWITCH***
put the new one in and vroooom. i was kind of spooked on how fast it started. and each time i turned the key it fired and ran like a champ. thanks for the help, Harley

 

Thanks for the update; most people forget to. I'll have to file that remedy in my memory bank incase it ever occurs to me.

 

*** note with the 32/36 on my 20r with the trd stage 1 cam i had to advance the timing a bit for it to run smooth.
in the pict of my crank pulley, when i adjusted the timing so it did not "cough" at higher rpms (2500-4000), with the vac adv cut and the timing light hooked up the tdc mark would be lighting just on the far left of the degree reader on the block. right where the little step is before it goes 90 deg to the block.
just thought i would post this in case someone was wondering.