Jacoboe21

i am having issues getting my carb to work properly. My truck starts up and isles rough and when I step on the throttle it dies. If I feather the throttle and get it to go above 1500 Rpms it's revs up fine from there and has plenty of power. I noticed that the passenger side flap on the carb does not move and stays wide open regardless of throttle input.

atcfixer

iTrader: (1)

Don't know a bunch about the 22r carbs, but sounds like you're running lean. The top flaps being fully open could have something to do with that. I looked at the two trucks I have here with carbs, and both are 1/2+ shut with the engines off. Passenger side I think is the first one to open with more air flow. I need to learn more about the carb setups, but pretty sure the top flap isn't working right for some reason.

Just for a test, assuming you can move the flap by hand, you could try to close it off about 1/2 way and reach behind the carb and bump the throttle and see if it responds better, or wait for someone with more knowledge of these carbs to reply.

Jacoboe21

I took it to emissions this morning and they told me it is way too lean with the flap open like that so I close it manually and the truck runs fine. The flap opens up all the way once throttle is applied and leans out I might just look for a new carb.

atcfixer

iTrader: (1)

I'd think there is either some sort of adjustment, or linkage that controls the flaps.

I'd sell you one of my carbs, but both that I know are good are on running engines. I did have another that was stripped down that I'm not sure if it was efi or carb, but I'm not banking on it being carb.

Jacoboe21

The linkage looks very complicated but I will look again and maybe I'll try to attach a spring to make the flap close maybe that'll buy me some time meanwhile it gets painted and I rebuild the front axle.

atcfixer

iTrader: (1)

Spring might work, might be the actual issue with it too lol.

bootscootboogie

iTrader: (1)

I used a small tie strap to secure the small arm that held that flap open on mine and ran like that for a long time. I will never use a aisin carb again. Too many vacuum ports / too old / too many small parts. Now if you're an A1 carb man like the old guy that rebuilds yota carbs in my town, you can make em work. But I think they're complicated as hell. Rig it up!!!

Jacoboe21

I am going to adjust the fuel/air mixture screw because I've been reading that it's supposed to be covered and I noticed mines is not covered indicating that someone has tampered with it in the past. My theory is that the carb is leaned out way too much so I'll richen it up and see what happens.

atcfixer

iTrader: (1)

Screw in the air/fuel screw till it stops counting the turns so you know your base line (lightly seat it, don't crank on it). I think typical setting is around 1.5 to 2 turns out, seems to be the same for nearly all carbs.

People had the same feeling about the quadrajet carbs from the 70's, my dad knows them well and could always get them running well and typically get pretty good mpg for a big car with a v8 (350 rocket and 455 oldsmoble). A lot of people went to holly, which either runs good idling, or floored and if it back fires you're changing the power valve. Not sure if Holly has changed their design much since the 70s or not.

I've never heard any problems with the Weber carbs, not sure how their choke setup is on them though. The OEM is floor it once to set the choke before cranking.

The problem running a carb'ed engine today is not so many people don't know how to work on them correctly. A tuneup was needed every once in a while to keep the carb in tune (changing seasons etc can throw them off a little, atleast on domesic, I think Toyota has something to auto adjust it atleast for altitude). Today you kind of need to know how to work on a carb or take it to someone that's used to working on carb'ed engines (small engines typically do).

Jacoboe21

So I removed the carburetor and cleaned it up then put it back in. I replace the fuel filter and it was nearly clogged! The truck had been sitting for 16 years and only has 150xxx miles. I started it up then the fuel pump started leaking out of the bottom where there is a small hole. I am going to replace the pump and maybe that will fix my problems.

atcfixer

iTrader: (1)

Yea, low float bowl (oem ones have a sight glass in the front of the carb) can cause lean condition. I asked my dad about the top flaps on carbs, and he said it should be the choke. He grew up working on domestics so it's possible Toyotas are different, but if it is the choke, then warm weather / warmed up it should be wide open.

If the fuel filter is plugged really bad, some junk might have got past the filter. Might be a bit of a pain, but pulling the carb apart and cleaning the bowl and jets wouldn't be a bad idea. I was assuming it was a new problem, not an already existing problem. While you're messing with the carb, you'll probably want a carb gasket kit or rebuild kit. The AARP is common to go bad and allow fuel to be sucked though the vacuum lines and suck into the intake (rich condition). I've had that on a couple of these engines. Most people just block it off, but you can replace the diaphragm too.

Jacoboe21

Thanks for all the info atcfixer I learned a lot about carbs these past few days. So after replacing the fuel filter which was clogged and the fuel pump the truck runs great! It only stumbles bad at around 1200 Rpms but I can live with that for now. I think the clogged filter was not allowing sufficient fuel flow and leaning it out. And you are right the choke flap is supposed to remain wide open when hot. Now on to the front wheel bearings and axle seals, and shocks then finally paint.

atcfixer

iTrader: (1)

I just did that job yesterday basically lol, Wheel bearings are pretty simple to get at. Take the 10mm bolts out of the hub, slide it apart, pull 12mm bolt for the axle, and set back together (keeps them clean). Pull all the locker hub bolts, and tap the edge with a small hammer to get the cone washers to come out and pull the locker. Then it's just ball joins and the two axle nuts/retainers. Ball joints do unbolt top and bottom which is nice.

EDIT:

Just noticed this is in the 84-85 section, solid front axles are probably a bit different lol, this was IFS.

Jacoboe21

Awesome! I think they are very similar I just ordered the 4 bearings, races and seals. Any idea on why it sputters at 1200rpm? Could it be the fuel/air mixture?

atcfixer

iTrader: (1)

Possible it could be the air fuel mixture. I'm more experienced with Honda ATVs for carbs. When you give it gas, and it kind of wants to go, then revs, it's a sign of being too lean. Since 1200rpm is pretty low, it could be the low speed jet partly plugged (if these have something like that).

The atv carbs have a pretty simple operation, slow jet works from idle to about 40-60% throttle, then the main needle jet is for ~50% to wide open. In cars/trucks there might be a bit more going on, but should be similar design more or less. There's something like 2 idle adjustments on the asin carbs (cold and hot), I think some sort of choke adjustment, and the air fuel mixture screw that normally has the cap over it. There's probably a good write up somewhere on how to tune your carb (assuming the inside is clean). Another thing you can do is do a plug check. Pull atleast one plug (all is best) and check what they look like. Thick black soot is too rich, super clean white or white powder is too lean, light brown is about perfect.

Here's a google image to better visualize.