I tested it as everyone said by turning off the car and pressing the pedal. There was no squirt, only a dribble sort of. I think that may be my hesitation problem.. How hard is it to replace, and how much does it cost?

Thanks,
Matt

 

I tested it as everyone said by turning off the car and pressing the pedal. There was no squirt, only a dribble sort of. I think that may be my hesitation problem.. How hard is it to replace, and how much does it cost?

Thanks,
Matt

 

my carb kit was $20 with all the stuff in it,,,not hard to replace, just be carefull not to drop the 4 small screws that hold the pump cover on, might keep a magnet attached to the screwdriver while remove/replace the small screws,,,,,,,not much at all to it,,,and makes a lot of improvement to your cars performance

 

my carb kit was $20 with all the stuff in it,,,not hard to replace, just be carefull not to drop the 4 small screws that hold the pump cover on, might keep a magnet attached to the screwdriver while remove/replace the small screws,,,,,,,not much at all to it,,,and makes a lot of improvement to your cars performance

 

How do you know what brand of carb you have? I think my carb has been replaced from the stock, so i'm not sure.


Thanks,
Matt

 

How do you know what brand of carb you have? I think my carb has been replaced from the stock, so i'm not sure.


Thanks,
Matt

 

do you have a haynes manual, check chap.3 and see if yours looks like it, go to auto zone and look thru their books, or library if not stock, i hope theres a tag or plate that says what it is,,,,,,good luck,,,,,,,

 

do you have a haynes manual, check chap.3 and see if yours looks like it, go to auto zone and look thru their books, or library if not stock, i hope theres a tag or plate that says what it is,,,,,,good luck,,,,,,,

 

or if you're lazy you can always just see if the top is blue and says mazda one it. Of course that's not the entire carb, but I doubt someone would get a new carb just to throw the old air box on it.
I'm not 100% on this, but I don't think other carbs would allow all the vacuum hoses present on the stock carb, so you can always check for the rats nest connections by the engine side of the carb.

 

or if you're lazy you can always just see if the top is blue and says mazda one it. Of course that's not the entire carb, but I doubt someone would get a new carb just to throw the old air box on it.
I'm not 100% on this, but I don't think other carbs would allow all the vacuum hoses present on the stock carb, so you can always check for the rats nest connections by the engine side of the carb.

 

Advice for the STOCK accelerator pump:

The stock carb is a Japanese made, "Nikki" brand carb made by the Hitachi company. Hitachi sounds familiar because they've had their fingers in all kinds of manufacturing pies over the years. Looking around your house you're bound to find a few things that contain Hitachi made components and circuit boards.

The AP (accelerator pump) consists of a lever operated diaphragm - located right in the housing. But chances are, that is'nt at all where your problem is! Of course there is the chance that your diaphragm is like old shoe leather, but usually by that time, all your other gaskets are so old that their sealing qualities are gone, and your carb leaks like a sieve.

The AP works like a squirt gun. It has basically a tube running from the housing to the rear fuel bowl (right behind the housing), and another seperate tube running through the carb body to the squirter nozzels.
There is a check ball in each of these, with a tiny brass wieght on top of each one, (two total).

When you LET OFF the accelerator, the diaphragm acts like a suction baffel, and draws fuel in from the bowl. It can't draw air in from the nozzels because it sucks that checkball closed in the tube, effectively sealing it.
When you DEPRESS the accelerator, the diaphragm now pushes against the fuel in the AP housing. The check ball in the fuel bowl tube pushes against its inlet orifice, and seals it...and the fuel can go out only to the nozzels.

...SQUIRT!

These check ***** are steel. Often they will suffer from piting, however minute, just from 15-20 years of a little condensation here and there. The pits are'nt really big, but help varnish and other sicky, crappy nasties to collect on the ball, making it not round.
The same crap collects around the rim of the orifice that is supposed to be blocked off by the ball, and so what you end up with is a leaky valve.
...kinda like what cheeseburgers will eventually do to your heart and associated blood vessels!

...And you don't know which checkball is'nt functioning, because you might not be able to pump out fuel, or the system might not be able to get enough in in the first place.

So...You need a rebuild.

A long shot:

You could remove the aircleaner, and unscrew the large diameter headed brass screw that holds the nozzels on. There is a tiny gasket ...don't lose it.
spray carb cleaner down the hole that the screw was in. If you spray too hard, and just right, the brass wieght and the checkball could come flying out into "Forgetit" land, so be careful. Better just to sray a little in the can cap and dribble it in.
repeat this a few times. Reassemble, and hope for the best. The other end is'nt serviceable unless you start removing parts of the carb; and for that trouble, you should buy a rebuild kit, and take the carb off and do it all.

If you decide to do that, we're all here to help.

 

Advice for the STOCK accelerator pump:

The stock carb is a Japanese made, "Nikki" brand carb made by the Hitachi company. Hitachi sounds familiar because they've had their fingers in all kinds of manufacturing pies over the years. Looking around your house you're bound to find a few things that contain Hitachi made components and circuit boards.

The AP (accelerator pump) consists of a lever operated diaphragm - located right in the housing. But chances are, that is'nt at all where your problem is! Of course there is the chance that your diaphragm is like old shoe leather, but usually by that time, all your other gaskets are so old that their sealing qualities are gone, and your carb leaks like a sieve.

The AP works like a squirt gun. It has basically a tube running from the housing to the rear fuel bowl (right behind the housing), and another seperate tube running through the carb body to the squirter nozzels.
There is a check ball in each of these, with a tiny brass wieght on top of each one, (two total).

When you LET OFF the accelerator, the diaphragm acts like a suction baffel, and draws fuel in from the bowl. It can't draw air in from the nozzels because it sucks that checkball closed in the tube, effectively sealing it.
When you DEPRESS the accelerator, the diaphragm now pushes against the fuel in the AP housing. The check ball in the fuel bowl tube pushes against its inlet orifice, and seals it...and the fuel can go out only to the nozzels.

...SQUIRT!

These check ***** are steel. Often they will suffer from piting, however minute, just from 15-20 years of a little condensation here and there. The pits are'nt really big, but help varnish and other sicky, crappy nasties to collect on the ball, making it not round.
The same crap collects around the rim of the orifice that is supposed to be blocked off by the ball, and so what you end up with is a leaky valve.
...kinda like what cheeseburgers will eventually do to your heart and associated blood vessels!

...And you don't know which checkball is'nt functioning, because you might not be able to pump out fuel, or the system might not be able to get enough in in the first place.

So...You need a rebuild.

A long shot:

You could remove the aircleaner, and unscrew the large diameter headed brass screw that holds the nozzels on. There is a tiny gasket ...don't lose it.
spray carb cleaner down the hole that the screw was in. If you spray too hard, and just right, the brass wieght and the checkball could come flying out into "Forgetit" land, so be careful. Better just to sray a little in the can cap and dribble it in.
repeat this a few times. Reassemble, and hope for the best. The other end is'nt serviceable unless you start removing parts of the carb; and for that trouble, you should buy a rebuild kit, and take the carb off and do it all.

If you decide to do that, we're all here to help.

 

I have the same hesitation problem on my 82 with stock carb. I realize that other things may be causing it, but I want to replace the accelerator pump first.

When looking at it, it looks like the mechanical linkage completely blocks one of the 4 screws, plus access is really limited. Can this be replaced easily with the carb installed? Does the linkage need to be removed to replace the AP diaphragm? Anything else need to come off?

My haynes manual shows everything with the the carb on a bench.

Thanks,
Ng

 

This thread gets a 5 star rating, thumbs up and 5 shots from the Glock in the air for the great specific information sterling put in here. It's by far his most lucid work yet. And I just happen to be looking for a tip short of a rebuild to fix up my present ride. Thanks, sterling!
..............................mar3.....

 

And 5 Stars to neil Gueldner For being New, and using The Search Function, rather than just posting the same question over and over like other noobs.

Great Example!

 

Good job Neil, we are too busy bitching at people for not using the search function and never congratulate people that do.. Excellent man

 

Thanks for the praise on my search abilities, but can someone answer my question?

Can you remove the AP with the carb on the car? Does the linkage have to be removed from the AP? Is there some trick to it?

Thanks,
Ng

 

Yes, you can remove it while it's still on the car. There is a retaining clip holding the fulcrum pin in the housing. Take the pin out and remove the four screws. There will be a spring and a diaphragm.
I seriously doubt that this is where your trouble is, though. I suspect that it is either with the intake or output checkball.
About the only thing you can do short of a rebuild is take off the nozzels and manually operate the throttle very slowly to see if the wieght and ball pop up. If they do, then your problem may be in the intake portion of the accelerator pump, and you can only get the wieght and check ball out by turning the carb upside down.
You're playing a game of "Hope I don't lose it" when you try this, though!
I think the ball and wieght are too big to pass thru the primary venturis because of the booster venturi being in the way, but certainly it's very possible to have them fly out and land in your secondaries...and then of course into your engine!