Jetboatking85

Update: I am getting fuel in the bowls now... the floats are just adjusted wrong i guess... i set them up for 2" of float drop like the instructions said to do... but this was not allowing the needles to open at all.. so i took it down a little more than 2 inches and now my front bowl is full, and my back bowl is 1/3 full... so more tweaking i guess is in order.


car tries to start on its own.

DivinDriver

iTrader: (15)

Measuring drop with gasket in place, yes?

Jetboatking85

Both bowls are getting 1/2 full... now, when i hit the accelerator nothing comes out the holes... what do i do now? and yes i am measuring with the gasket in place.... i measured again in mm this time... and bent the mounting arms of the float to be level with the base of the float... and then adjusted with mm as per the FSM and its dead on 1/2 full on both sides.

DivinDriver

iTrader: (15)

Next step sounds like your accelerator pump circuit is gummed up, or the linkage for it is disconnected.

This thing here:


Connects like this:


Has several components in it's circuit, including jets, air bleeds, and two check ***** and two weights. When they get gummed up, the pump won't pump gas out the jets.

t_g_farrell

iTrader: (1)

Well, thats good progress, you've made it to step 4. Like DD says, something is either not
pumping or theres a clog. Did you put the AP diaphram in correctly? It will go in wrong with no
problem and you get no pumping action. The metal **** on the diaphram has to be facing out
so the arm, when it moves, contacts it and pushes diaphram in. The spring then goes on the other
side to make the diaphram push back out to fill up again.

Jetboatking85

thank you for the awesome reply once again!... the diagram that you have is way easier to read than the one that i have.. .and i think i can see what i did wrong, ill check it out when i get home.

DivinDriver

iTrader: (15)

That diagram is from the Mazda Carburetor Manual for 1979-1985, which along with many other valuable references is downloadable from the link in this thread (which is stickied at the top of the forum):

https://www.rx7club.com/1st-generation-specific-1979-1985-18/download-copy-your-year-fsm-click-thread-get-link-894736/

The one-page instructions that come with a carb kit can't hold a candle to the factory references. Especially after you've had some time to mark them up yourself.

Jetboatking85

i have a FSM, its about 900 pages and in a binder.

however the pictures are hard to read, and its pretty old (came with the car)

so im downloading and making all new manuals right now thanks

Jetboatking85

ok... i got it pumping when i hit the accelerator... and it starts up and runs on its own with the CHOKE ON!.... untill i turn the car off, or let back in the choke..

as soon as i let the choke in the car dies, what next? is this all vaccuum related at this point?


also car smokes a bit but im just chalking that up to it not running in so long. smells like an old lawnmower.

any suggestions on where to go from here?

t_g_farrell

iTrader: (1)

Its too lean probably, thats why it runs with the choke on. You need to adjust the air mixture.

Jetboatking85

i tried adjusting the screw at the base of the carb ( idle bypass) 1/4 turn at a time with no diference, could this be caused by possible bad exhaust system? clogged cat? or the vaccum hoses that are open in the rats nest? ive got other issues i dont quite know how to figure out yet lol...


i know i have other issues, however i think the car should at least be able to run on its own before needing to address them

DivinDriver

iTrader: (15)

Too lean can be caused by vacuum leaks - - like some of those missing rats nest connections can cause - - just as easily as by mis-adjusted mix screws. Any connection that you can hear/feel sucking air when it's running on-choke need to be capped.

Jetboatking85

ISSUE!... i still cant get the car to run, this is the same problem that i had when i took it to the mechanic after giving up.

the car will start and run if i turn the choke on and pump the crap out of the pedal.

everything is hooked up somewhere and im not hearing any leaking air, however as soon as i touch the choke at all it revs up a little and then dies.

I only have 1 mixture screw at the base of my carb, and no matter what i set it at i dont get any result, i cant find anything that sais what the # of turns this screw should have is.

the manual talks about an air adjust screw and an idle air mixture screw, however i simply only have the 1 mixture screw... on both my old original carb and the one that is on the car.

please help im getting frustrated and want to break somthing.

DivinDriver

iTrader: (15)

Depending on year, some of the carbs only have one screw in the left side. Others (mostly older manufacture) have two.

Sounds like step one for you is to definitively ident which carb you have - - which may or may not be the original one from your car.

If you take off your air cleaner and take pix of all four sides and the top, and post them, we can help ID the carb for you.

Jetboatking85

standby, im doing it right now

Jetboatking85

this is all i coulg get my camera into

Jetboatking85

top

DivinDriver

iTrader: (15)

If your carb is a proper 83-85, then the 79-85 Mazda Carb Manual I mentioned before covers it in huge detail, starting on printed page# 57 (page 104 in the PDF file).

The diagram on pg 61 (108) shows the location of the 'two screws'; one (Mixture Adjust Screw (MAS), part 111 on the diagram) on the left center of the throttle body, and the other (Throttle Adjust Screw (TAS) part 113), rearward from there, touching the throttle linkage.

These are the "Two screws" the instructions talk about.

On page 68 (114 in the PDF) , Part B, steps 1 and 2 tell you how far to open these screws for your initial settings: MAS you close lightly (just til it touches the seat) and then back out 3 turns; TAS you tighten until the spring bottoms out, then back off 6.5 turns.

Those are the factory intial settings, which are the best place to start adjusting from. If all else is right with the carb, the car should start and run with those settings.

The whole of part B, and the "Adjustments" section starting on page 71 (118) are all about making sure your carb is ready for installation and adjusted in such a way that the car will start and run well enough that you can fine-tune it.

DivinDriver

iTrader: (15)

It looks to be an 83-85 carb, but there are parts missing - - probably removed as part of the 'smog delete'? - -that may be making a difference. I'm not expert on the FB's, But I noticed that your vent solenoid has lost it's connection (being unable to open the vent will make a carb have troubles), A choke pull-off diaphragm is missing, The choke thermal assembly's gone, possibly other stuff.

Of those, the vent solenoid not openeing whenthe ignition's one is the only one I can think of that could contribute to your problem - - without bolw venting, you end up with a partial vacuum over the top of the gas in the bowls, and fuel can't flow properly.

Was the vent maybe modified to be always open? Or did the wire just get sheared off?

Jetboatking85

ok i adjusted the screws to the turns you specieied from the manual. and it wil start if fully choked, and run while choked... but dies when i release the choke even the slightest bit.... ive noticed when the car is off the bowls are slightly fuller than 1/2, but when running with the choke on the bowls are dead even at 1/2.

could this be a float adjustment still

is it possible for a vaccum to be hooked up "backwards" ? still causing a leak of some sort? i just have stuff hooked up where ever it will go for the moment to see if it will run.

Jetboatking85

i adjuststed the bowls ever so slightly, and now the levels are sitting at 1/4 and the car asks the same way (starts on choke, and idles higher)... but as soon as the choke is released the car dies...


it seems to me that there is somthing wrong inside the carb not allowing the fuel to be sucked out of the nipples down in the barrels. but ive taken everything apart and its all clean, i can see through the holes.

the only other thing i can think of is a vacuum hooked up wrong... i guess i need to do the rats nest removal steps and see what happens????

im at a loss... i dont see why it shouldnt run.

Jetboatking85

i think the vent has been bodified to be always open... they man i bought it from said it was "modified" for emmisions removal.

DivinDriver

iTrader: (15)

Logically, if opening the choke even slightly causes the car to stall, and the MAS & TAS are at the normal settings, then you are either getting too much air (like from a serious vacuum leak) or not enough fuel for the air you are getting.

General causes of not enough fuel, if bowl levels are OK (and they were, when at 1/2 window), are plugged passages or jets/bleeds in the primary circuits. That's where you should start investigating, would be my bet. Especially, make sure the idle slots and the passeges that feed them are flowing (by blowing comp. air or carb cleaner thru them) and make sure the jets and bleeds are not plugged, and the right ones are in the right holes (there's a chart in the book).

Unless you can find a vacuum leak.

project7s

iTrader: (5)

i went through this same problem with a 7 i had, it was doing the same thing as yours the problem i found was a little peice of trash was stuck down in a passage way. it took forever to find it and when i did you could hardly even see it but after that it ran like a champ, i would bet that is what your problem is. good luck

Jetboatking85

Im giving up on this POS nikki, ive taken it all the way back off again, and cleaned it out -again, I can blow b12 through the channels and watch it come out through the holes. When i replace all the little pieces and spray b12 in the nipple. i can watch as b12 fills the bowl. re-installed carb, and no improvement, still wont run without the choke.

im in the market for a new intake mani, and carb set up. Also looking for full exhaust replacement. Any ideas? or know anyone that has this stuff they would be willing to sell for cheap? i need a carb ready to go... no more rebuilds, im done.