I got an 83 gsl that I just started working on. It'll start right up and after it warms up, it'll idle just fine, but anytime I go to give it any more than say, 15% throttle, it starts to bog, and for Godsakes, if I even try to floor it, it'll just die out. Now,obviously this sounds like a fuel problem, but the problem is that it's been 10 - 20 degrees out lately (tonight is supposedly gonna be between -30 to -50 below out (wind chill factor). So as you can see, I don't exactly wanna be out in the freezing cold trying to diagnose this annoyance. My guesses are: bad fuel pump, another bad filter, dirty (small) filter(s) in the fuel line that enters the Nikki carb, or a gummed up carburetor........possibly even something ignition related too---such as the Crane Cams low impedance spark plug wires on there. Any help and/or insight would be greatly appreciated!!

 

Carb rebuild.

 

sometimes when it gets really cold, my carb gets screwed too, make sure your exhaust heated air intake pipe, and snorkel works to keep the air going in the engine warm

 

You're on the right track.

It could also be that your accelerator pump my need some attention. When it warms up, have someone pump the gas pedal while you look down the carb. Do you see a mist of gas? If not, then you probably need a new AP. If the carb has never been rebuilt then you might want to consider it. There are some other guys on this forum that are way better with the Nikki's than I so hopefully they'll chime in with their own 2 cents. Good luck!

 

Tha Mazda God demands sacrifice!!!!!

If the Mazda Gods demand it, then get out into the cold and pay your pinnance, sinner.

On most carbs if the accelerator pump is bad, the car will bog down upon a quick change in the throttle plate but will make a smooth rev upon gentle acceleration.

The Nikki seems to be a pretty good carb to me. Wonder if the aftermarket carbs provide all of that promised horsepower on a engine with minor modifications.

 

Sounds like a possible accelerator pump problem. Operate the throttle and look to see if its squirting fuel out of the nozzles.

 

Alright, here's what I forgot to mention..... I just finished doing the rat's nest removal, along with the switch-over to making the secondaries "mechanical". I also "shimmed" the accelerator pump with 3 gaskets per side, just as Sterling suggested in his writeup. But, here's where the problem lies......the car runs almost the exact same way as it did prior to any of this work, and yeah, I checked to see if the accelerator pump was working properly as well.......(mass confusion!! )

 

oops..... ya forgot just a few minor details

 

Inittab, I agree with your suggestion about rebuilding the carb, just not too excited about doing another one. The biggest problem I had was getting all that damn gasket material off both sides of that plastic somethin or another plate thats between the carb and manifold, the rest wasn't all that bad though. Oh well, I'll see what I can come up with though. Thanks for your help guys

 

 

Well is the accel pump working or not?????

 

Yeah, the accel pump is working. I'm thinking that I should just go ahead and rebuild this one, judging by the way how rough it's running. ---- I do, however, have a problem with the way the choke is working. Before I removed the rats nest, going by the tutorial on the MAZSPEED website, the choke seemed to work fine, now it hardly works at all. I didn't remove or mess with any cables, and I remember capping every source of vacuum that wasn't going to be used, as well as rechecking all of my work. The choke plate is still operating the same, and it idles only slightly higher (like 50 rpm's), but it still wants to die out. The only extra carb accessory that I removed was that vacuum operated dashpot looking thing that's used for the A/C.
Well, if anyone has any input, let me know.
Thanks

 

The emissions removal tutorial doesnt not affect the choke in any way. Maybe you knocked something off accidentally while doing all this work. That where my money is.