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Just put a rebuilt carb in my 77, I finally got it tuned (or so I thought) but sometimes when I turn the truck off. It will back fire. It usually only does it if I am driving for a little bit. Any suggestions on how to rid myself of the gun fire??

Hey paradox,
Well the first thing I have to ask is do you still have the emissions crap on your LUV? If so than that is usually where that telltale POP!!! will come from. The smog pump (air injection) will heat up way faster than the rest of the motor and fools the rest of the works into thinking it is running rich,
it advances alittle timing here retard fuel there and voila Miss ignition. The solution? Let the truck warm up a little longer and advance the timing just a smidge (a degree or 2) And check your mixture screws. And last check the choke to make sure it is coming off properly. My LUV was the same way when I first got it and man were my neighbors pissed. Tried all this, it worked and then I tore all that nasty emmisions stuff off. It works better!!
Hope this helps.

Dave

thanks bro... i will check all that stuff.

Check idle cut off. it may not be pluged in. screw out cut off solenoid place to ear plug in and listen for click.

After dark lift hood and look for sparks on ignition wires and distributor coil and voltage resistor.

Under the manifold just to the right if the carb is a vacuum line which loves to fall off this makes mine backfire.
???.

well I checked all my hoses and adjusted the idle a bit and it seemed to be going well, though it would still backfire a little. I couldn't leave well enough alone and thought what the heck I will adjust the valves while I am sitting here under the hood. So I adjusted the valves, no problem. There were a couple that were a little off but nothing major. So here goes the point of my story. I go to work early in the morning prob around 4am. I let the luv warm up real well. I drive to work and right when I am pulling in to work I let up on the gas and down shift and BOOM. It backfires and takes my muffler with it. The whole thing blown in half. Now, it isn't like the thing is brand new but damn!!! So any suggestions on what I should do? I still have all the emitions crap on and I don't have to get tested so I am thinking about taking it all off. But I am not sure what I can take off and plug, and what I can't. Any help would be great.

Good thing that didn't happen around here. They would start shooting back at you.

Hey paradox,

I love to hear bout someone taking all that smog crap off!
First take the smog pump and all related hoses hell you can take the bracket off too if you want. Next take the air injection tube and related off now there are holes right above the spark plugs you have to plug those off find some bolts that fit and sinch em down. also the tube coming off the exaust can go and also plugged. Then take the vacum lines and plug those also(all you need is brake booster and vacum advance). Now I would recommend you set aside atleast a day to get it out of the way and adjust everything again. Then once you have all the air inj and vacum lines out of the way you just have to chase down all the bugs that come with changing the air fuel mix and some timing will be involved. But let me tell you it is all worth it your LUV will run better and won't have the neighbors ducking when you down shift!!!
Hope this helps...

Dave

Thanks Dave that helps so much...

No problem man. Glad I could help.

Dave

can you pass emissions without it

Dude I couldn't pass emissions with it. So I had it licensed in a different county. So, I don't care if it passes or not. I just want it to run well.

Sweet!!! Don't you just love loopholes.

what about any of the electrical smog crap that is hooked up to the hitatchi carb.... can you just unplug it or snip it and cap them off??

Paradox I feel for you!! I bought mine from a guy down here ( I live about 35 miles south of you) anyway I asked about the emission crap and he said that 75 and older dont go through emissions here I dont know how much truth there is to it but in the last 3 years I have registered it noone has ever said anything to me. Well anyway I like the little loophole you found thats a great idea. I also have my Ford probe licensed in Texas so I dont have to worry about emissions for it either. lol Thats my little loophole. lol

it's kinda cool now.ever since i took off all the smog stuff my truck doesn't backfire.i'm running flowmaster and i have heard alot of bitching about it backfireing.there's your answer take the smog off

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1980 luv sport 4x4 Just a memory now
Frame rusted from the inside. Truck stripped and now looking for a new donor in southern ohio