# hiccup around 2K



## earling (Mar 30, 2011)

HI folks,
New here ...
Proud new owner of an '84 2WD 720, Z24 eng., 5 speed, reg cap, one ton

Here's the deal: I've pretty much been through this thing top to bottom. New fuel pump, new plug wires, p.o. did the plugs, cap, rotor, new stock carb (which I had to remove and re-seal, MASSIVE vacuum leaks around the base), I've done the timing, tappets, mixture screw, removed all the emissions stuff including EVAP cannister and EGR and capped/plugged all relevant orifices. Put in a fuel press. regulator, can't think what else. Currently with cheapo Advance auto fuel pump running at 2 PSI which is supposedly low, though if I hook up the old cheapo aftermarket pump in series with it, pressure goes up to about 7, which forces me to mess with the float level which still does not solve Problem #2, which I'll get to.

Basically the truck runs like a champ. Perfect idle, lots of power.

However, the truck runs noticeably better with the timing retarded to something like 0 degree BTDC or even a few degrees after TDC as far as general punchiness and acceleration. I've got both spark advances still hooked up, vac. and centrifugal. I can't say for sure if it makes any diff. if I unplug the vac advance. Stock 3 degree BTDC is OK, but not as good as slightly retarded. I realize that one of the emissions features was a temp. controlled vac. switch which let in a leak to retard spark at either high or low temps (not sure). Maybe that's a problem.

The main issue is that the thing has a chronic hiccup at around 2K, or just off idle when it's still running on the primary venturi. Feels like the transition between primary and secondary barrels. Nothing seems to change the hiccup. Changing the float level does nothing. Timing seems to have nothing to do with it. There are no vac. leaks that I can currently find. It's almost like the ignition's cutting out for a fraction of a second.

I AM STUMPED

anybody got any clues????
thanks so much, about ready to pop for a Weber


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## jdg (Aug 27, 2009)

Back in the day, a hiccup, or tip-in stumble, off idle like you describe usually ended up being caused by too much throttle plate at idle, running too much off the mains and not enough off the idle jets, thereby causing the accelerator pump to be too far into it's travel to provide enough of a 'shot' during tip-in.
It could be that you don't have ENOUGH of a vacuum leak, like a plugged up PVC or something similar. If you did have just a little bit of a vacuum leak, you could close of the throttle plates a bit more at idle, and give the accelerator pump a bit more room to do it's thing down low.
Or could be that your accelerator pump is shot. Does the hiccup 'not happen' if you kinda double-pump the gas pedal a bit when leaving a stop sign or right when the hiccup happens?
Any of this make any sense? (keep in mind I don't own a Datsun/Nissan with a carb, I'm just going off what I know about carbs in general, of all types)


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## earling (Mar 30, 2011)

*hiccup*

thanks for the response.

First of all, I guess I should be clearer--it's not off of idle, exactly. It's more like around I would guess (with no tach) around 1800 rpm, about when the accelerator pump is probably done doing it's thing, or when the carb is switching from primary bore to secondary(?) When you're about 2/3 of the way toward upshifting, driving casually. . . .cough. It's fine if you floor it. The carb is brand new rebuilt. Actually, that's an interesting idea--I could leave one of those capped off emissions ports open, adjust idle accordingly and then see. I suspect that I upset the poor little carb by ripping off all the doodads that mess with vacuum and timing. I did hook up the choke pulloff (whatever it's called) to a vacuum and nothing changed. I also played with the accelerator pump lever, put it in the second (lower) set of holes in the piston shaft, which raises the piston but doesn't change the stroke apparently... made it much worse. Double, heavier coughs. So, it's a lean condition, for sure. Runs fine when cold, on choke.


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## jdg (Aug 27, 2009)

Is this carb a vacuum operated secondary or mechanical or otherwise?
If you can floor it and it's all good, I'd doubt it's a primary/secondary transition thing 'cause most secondaries don't come into play unless you're getting into it. The primaries are what do the bulk of the work even on the highway...again, unless you gotta get into it for a hill or passing or something.
However, if it is actually getting on the secondary bores, there might be a couple of small, tiny little air holes above the throttle plates or maybe the air valve that draw fuel as the secondaries crack open. On a Q-Jet, it's basically called a secondary 'pump shot' even though there is no actual accelerator pump. As the air valve opens up, just as it cracks open, there's enough suction there to suck fuel out of an auxillary fuel well in the bowl of the carb.
And is this 'cough/puking' more of a chug or a backfire?


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## earling (Mar 30, 2011)

It's got a vacuum operated secondary. It also is in not into the secondary bore yet when it chugs/skips. It's definitely not a backfire. In fact, today at a certain float level and running only one fuel pump, I got it to the point where it was a soft skip, almost sort of kind of not that terrible. But obviously not really there yet. Still enough to bug the s--t out of me.It has an almost motionless, perfect idle at about 800 RPM, and will spin the rear wheels from a dead stop if you floor it. (with no bed on it anyway)

advancing or retarding timing has no effect, opening and closing off various vacuum ports has no real effect, float level seems to do very little, playing with the acc. pump made it worse, raising the fuel pressure from 2 to 7 lbs. did nothing (by running two pumps in series), running a hot lead to the coils directly from the battery did nothing (except making it impossible to turn off the car with the key), pulling and plugging the vac. advance did nothing, moving the vac. advance hose to different nipples did nothing. I don't know much about these hitachis, but if it were a Mikuni on a motorcycle, I'd go for a bigger pilot and maybe move the needle up a notch. . .


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## jdg (Aug 27, 2009)

About 2/3 the way towards upshifting, about the same time that the vacuum advance and mechanical advance on the distributor would start to reach maximum advance?
Thinking that just maybe the phasing on the distributor might've gone out???
Not the timing itself...that's not what I'm thinking of...
What I'm thinking of is when the engine has maximum advance dialed in (maximum vacuum advance plus enough rpms to crank out the maximum centrifugal advance), the rotor is too far past the spark tower for the spark to reach the tower.
In an old GM HEI, this would usually happen if the 'pole piece' (the pickup) inside the distributor had slipped somehow, or if the distributor rotor mount had slipped on the shaft somehow...which is possible 'cause I did it with a hammer accidentally once or twice.


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## earling (Mar 30, 2011)

Ummm, if I understand correctly, retarding the timing should correct the problem or reducing the amount of spark advance by plugging the vac. advance feature.... which I've done (and done, and done) It's a good theory, but here's what I'm pretty sure is happening. Which, if it's the case, is the usual "to simple to be true." But you might have been right about the acc. pump. 

I took the top off the carb, started playing with the acc. pump. It seems to do jack shit until you push it ALL the way down with your thumb, hard. It seems to do nothing if you're operating it in the subtle range of motion consistent with the actuating arm. I took it apart and it appears to be that the new rubber piston is too tight in the bore for the spring that gives it a gradual application to be able to push it down. I'm pretty sure it's just sitting there in the bore. I'm going to try and replace that spring with a stiffer one from the hardware store, or with a piece of copper tubing--to hell with gradual action. I want the full spurt.

Will report back. Thanks for the theories so far.


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## earling (Mar 30, 2011)

Jesus H., pardon my french

I just pulled the piston out, and lo and behold the rubber cup is torn at the flange. Now where in hell do you get Hitachi DFC382 parts I wonder? time for a little google


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## earling (Mar 30, 2011)

correction DCR384


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## earling (Mar 30, 2011)

answer is... the local Nissan dealer.


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## jdg (Aug 27, 2009)

Ya, sometimes my theories suck balls  That's why I inject them with a lot of big words and make them sound important.
Accelerator pump cup torn? Ya, that'll do ya. Good luck...


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## earling (Mar 30, 2011)

I believe that was one of your first theories... and mine too only I was a sucker for the "rebuilt good as new" theory so I didn't bother to look. Good thing nobody's paying me by the hour


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## jdg (Aug 27, 2009)

Gotta kinda be careful with those accelerator pump cups (and related parts)...

I went thru 4 of the them in my ThermoQuad on my RV last year ('76 Dodge 440) because I didn't realize that I was "overstroking" the accelerator pump while checking it before installing the accelerator pump arm. Turns out when I "overstroked" it, I bottomed it out too far in the bore where the metal wasn't finished quite so nice and it tore the damn thing up.
On the last cup, I installed it, but didn't move it until I had a good idea as to how far the thing was actually supposed to move, and then checked it only in that range.

I guess what I'm getting at is the fact that it's just maybe possible that you trying to check the accelerator pump's squirt action might've actually torn the cup rather than the cup being torn in the first place.


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## earling (Mar 30, 2011)

*rubber*

Point taken... I even suspected that by putting it in and out of the bore a few times I might have ripped it, because inside the bore is a ledge where it narrows and really squeezes the cup down, and I wasn't really all that gentle pushing it past that. Then again, the tear is at the upper edge where the metal flange it's mounted to can wear on it from the inside, so I'm pretty sure it wore out over the natural course of things. Sure hope so because I want a identifiable problem with an identfiable fix...
Also, part of the data is that the truck ran exactly the same with the acc. pump hooked up and not hooked up long before I took it out and experimented with it.
When I put the new one it, I will grease it, and twist it in gently, and not even test it or even look at it. I might even leave it in the plastic zip lock bag it comes in


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## jdg (Aug 27, 2009)

I said pump 3 times, cup 4 times, overstroking twice, squirt once, and 'bottomed out' once.
You said rubber, bore x2, squeeze, twist it in, not even test, not hooked up, and leave it in the plastic bag.
Are we still talking carbs? 

At any rate, I'm guessing once you get that new pump in there, and get everything set back to stock, there might be a marked change in the way it picks up off idle. Might just be a brand new engine. Or you'll find something else amiss...ain't that the way it goes...


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## earling (Mar 30, 2011)

If I were twelve I'd write "lol" after that

Yeah, we shouldn't even be talking about it. I don't want to jinx my new rubber pal (that is my "new Hitachi carb part") which should have been here today but was "referred" to a warehouse in bumford so it'll be here monday, or "monday" in quotes

Oh yes, HOPING for the "new engine" phenomenon.. . if only $12 could do that

One nice thing about carbs--they're stone age, and you get the rush of one plus one = more or less two. More gas squirt equals better pickup


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## jdg (Aug 27, 2009)

If I were 12, well, ya, I probably would too, but I would also multiply 12 by 3.5 

I'm continuously amazed at what a $12 (or otherwise) part will do for a guy after X number of so-called mechanics, or "I heard from someone that...." has already spent loads of $$$.
The guy next door has an '02 Chevy diesel pickup. Wouldn't start without using a shot of ether down the intake, then it runs just fine.
Today, this afternoon, like 6 hours ago, the shop called him up and wants to swap out all his injectors and high pressure pump to the tune of $2,200+. Luckily he called me up right after the shop called him to tell him that little bit of news.
I bailed out of work, went to the local CarQuest, bought a pair of glow plug relays ($30 each), picked him up, went to the shop. We walked in, I stood on the tires, reached towards the back of the intake, swapped out the relays (took about a minute total), started up the truck, gave one of "those looks" to the mechanics, I flashed the "service manager" the "LOSER" sign, mentioned a few things about the rip-off tactics, made sure the other customers were able to hear the conversation, and left.

In short, good luck on the part. Don't look at it. Don't think about it. In fact...what was it again?


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## earling (Mar 30, 2011)

*smart ass*

Oh good god don't get me started on the venal and wicked ways of the Modern Auto Industry
First of all, most young guys who work on cars can't even think without an OBD II plug in front of their noses. Maybe it makes me a bitter old fart, but I am about 50% committed to driving pre-OBD II cars for as long as you can find them on Craigslist, and carbureted, to boot. Used to be, back before closed loop fuel injection, that a mechanic had a basic set of theories to work off of, and the educated seat of his pants, and smelled and listened and thought a while, and turned a few things, and thought some more, and went through the checklist (timing, vacuum, gas/spark/compression, rich/lean, cold/hot, wires, cap, rotor...) and usually nailed it within a reasonable amount of time without too many parts being wasted. Nowadays they read the codes, charge you $70 to scan it--for each code!!!--pick up the phone and order a mass airflow sensor at about $280 a pop, plug it in, find out that wasn't the problem, take a lunch break, and warm up the scanner for another go at it. I can't see why anybody would even want to work on cars anymore for all the satisfaction that gives you.

I don't think I'm going to spend big bucks on a new car until they're importing little 2.2 turbo diesel one ton pickups into this country, which may not be until 2025 as far as I can see. (BTW, all over Europe they're tooting around in 50 and 60 mpg turbo diesel cars, no automatic trannies, sometimes 2 or even 3 cylinders. A 1.2 is not unheard of. Not here. God forbid)

anyhow, your friend owes you. Glow plug relays... the thing of it is, I would have had to read some sub-literate shop book for days before I even found out there was such a thing. And don't get me started on shop books. . .


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## jdg (Aug 27, 2009)

I can smell what you're cooking (as long as you got some bacon to go with it)...
I can swing both ways these days, carb or OBD, doesn't really matter. I grew up with carbs, but also grew up with computers (both programming and building hardware), so the transition to thinking OBD/fuel-injection wasn't too difficult.
I think one of the bigger problems people in general have today is not being able to think on their feet. If it ain't in the book, it must not exist, that sort of thing. Freekin' amazing how many people can't put two and two together, and if they do, they get 22. Most clowns only learn what's in the book and nothing else. College is good for what again???

And yep, Europe has the good in some respects. My daily driver is an '88 Chevy Sprint Metro, 2 door (228K miles, 54+mpg summer). It ain't pretty by any stretch, 3 cylinder 1 liter, white, and those special lightweight body panels (i.e. rust), and it's a bit cold blooded. Bought it for $300 back in '98. Still going. I would dig getting my hands on one of those 3 cylinder diesel cars like they've got over in Europe. The Mercedes 4 cylinder diesel mini-vans we drove while I was temporary duty in Germany had a load of power and as far as I could tell got GREAT fuel mileage. I still can't figure out how they started on cold morning without glow plugs though...

As far as the guy next door...nah...he don't owe me nothing. We hook each other up with whatever needs getting done.
We'd all be a lot better off if we'd all figure out that "one hand washes the other", "you scratch my back, I'll scratch yours", etc.

And as far as figuring out the glow plugs, I could hear the relays kick on and off without a drop and rise in voltage on the gauge on the dash after turning on the key and watching the "WAIT" light.
Popped the hood, 4 fat wires coming off the positive terminal; one straight to the starter, one to the other battery, one straight to the fuse box, and one thru a big ol' fuse straight over to the glow plug relays. Piece of cake...one thing leads to another.

Ahhh.....rant over....


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## earling (Mar 30, 2011)

I actually made my peace with OBD II in this '96 Dakota 4-banger I have. It's a really nice, insensitive, unfussy, simple uncluttered EFI system and now that I've swapped out the original throttle body with a bored job from a Texas place (best $89 I ever spent), it runs like it should. (Question being, why didn't they use a bigger throttle body in the first place? Mileage is the same. Power is miles better, starting, throttle response, everything vastly improved.... wtf (??!!)) 
However, I had a '97 VW GTI that made me hate modern emissions with a passion. I won't even go into it. Suffice to say, I exhausted almost every avenue trying to satisfy the picky mothereffin' computer in that thing.

Love the Geo Metro Sprint. You're walkin' the walk. I'm trying to get under the radar in this Nissan. Can't wait to ditch the cat, been wanting to do that for years. Maybe we can start a beater car movement.


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## jdg (Aug 27, 2009)

'96 Dakota...that had a straight up multi-port system on it right? Nothing "complicated"? My '01 Dodge is the same way. Basic computer OBD2, old school distributor except for computer controlled advance. Almost as easy to troubleshoot it as it is to work on my old '74 Malibu (SB350 w/2bbl Rochester).
And I run, don't walk, from VW's with electronics on them. That VW computer stuff is about as weird as it gets.

And for the Geo Metro Sprint...no no no...I could get it that good.
It's an '88 CHEVY SPRINT METRO. Different animal. Like a Chevy Sprint with a 3cylinder 1liter but stripped down, weaker cam, taller 4th and 5th gear, no options, I don't even think the thing comes with insulation so I don't drive it in the winter. Computerized carb (i.e. dancing needles), mechanical distributor (centrifugal and vacuum advance), still all original under the hood and the original cat is still in it. Have to downshift on 90% of the hills around here, takes forever to get up to 75mph, if I can even get going that fast (impossible with any headwind). But I can park the damn thing Anywhere and at most, takes 8 gallons to fill, in and out of the gas station. Incidentally, I spent the last tank of fuel "beating on it", trying to get bad gas mileage, see how low I could get it. Well, 38MPG is as low as it would go. The tank before that, normal driving, got me 48MPG. Come summertime, I'll be looking at 54MPG+, more like 60+ if I keep my foot out of it. It's got a hell of a wrist pin knock when the engine is cold, had the same knock for the past 10-11 years or so, and still doesn't smoke or burn a crap load of oil.

As far as the beater movement...I've got one stipulation...whatever it is, it's gotta be mechanically sound and running good, whatever mod's it takes to make it reliable is all good. If it looks like ass, who cares.
Function over form...or as I like to put it...Primer over rust...


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## earling (Mar 30, 2011)

so... no dice on the acc. pump. No difference. I went out and got several gallons of high test, no difference. Hooked the choke pull-off up to a manifold vacuum port and the thing went crazy letting in what sounded like masses of air, so I adjusted mixture screw and idle screw to suit, made no difference, put it all back to normal again. The only time the thing doesn't cough if when it's on choke and idling high. Put the air cleaner housing back together, no difference. Man that's one solid little unmoveable cough. Wish I knew somebody with a weber to try out .... 
I'd like to try an in-car vac. gauge, see what's going on 

I guess I need to study up on that primary circuit, figure out exactly what's going on at around 1800 rpm, 1/3 throttle. I would figure that's a low vacuum situation... that's about as far as I get.


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## earling (Mar 30, 2011)

and there's more ... I even drilled a hole in the acc. pump actuating arm about an inch closer to the pivot and hooked up the link from the throttle linkage to it to super-activate the acc. pump. That actually lessened the cough but obviously isn't the solution so I put it all back. The acc. pump chapter is closed, the thing is working fine

I'm thinking emulsion tubes and primary jets at this point. Or a Weber.


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## jdg (Aug 27, 2009)

earling said:


> I guess I need to study up on that primary circuit, figure out exactly what's going on at around 1800 rpm, 1/3 throttle. I would figure that's a low vacuum situation... that's about as far as I get.


I'm think that 1800rpm 1/3 throttle is a HIGH vacuum area...high manifold vacuum, possibly low-ish "ported" vacuum area.
Since the acc.pump didn't do anything for you, I'm going out on a limb and guessing you've got a decent vacuum leak somewhere in there. Get a can of WD40 or whatever you got that's flammable and spray it around in there, well, everywhere but the intake opening anyways.
One of the ways I used to test my idle mixture "back in the day" was to get it all warmed up, at idle, and pump the hell out of the brakes. A decently tuned carb (just a hair on the rich side) would idle up just a bit as the vacuum bled off from the brake booster. A carb tuned "in the middle" or towards the lean side would make the engine start stumbling right away.
Might not matter in this case since 1/3 throttle is surely on the main circuit by then...but...


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## earling (Mar 30, 2011)

actually, hold on to your seat (and thanks for the pumping brakes idea---but I'm not too worried about the idle mixture).
I found a tech article online that discusses Hitachi carbs, and there are there's this primary main air bleed. Another article about old fashioned emissions in colorado has a mention of soldering and re-drilling an air bleed to richen or lean out the mix. I've got mine here in the O.R. and I'm about to solder up two of the four holes and see what happens. What else has a guy got to do on a cold shitty night?


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## jdg (Aug 27, 2009)

Soldering on an aluminum carb body? I don't think that'll work out too well. Something a bit less invasive would be JB-Weld. (another back in the day..coming right up)...
"back in the day" (see there it is).... I built up a Buick 231 V6, put an 850CFM Q-Jet on it...huge carb, small engine, ran like a bat out of hell except when I punched the throttle. If I eased into the secondaries, it would pick up just fine.
Anyways, there's a set of air bleed holes that would grab gas just as the secondary air valve opened up. Punch it and ALL the gas from the wells would dump into the secondaries. Closed them up with a tiny bit of JB-Weld, drilled them back out with a sewing needle, good to go. And not only that, but a few years later when I needed the carb for another project, I was able to pop the JB-Weld off with a small screwdriver and return the carb back to normal.


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## earling (Mar 30, 2011)

ooops....
So I performed the operation and ruined my nice idle, and maybe cut that cough in half, or muddied it a little. Turns out I pulled the wrong thing--I soldered up the main slow jet (hard to decipher this shop drawing on cheap Chilton paper) and made it run like total crapola at idle, totally unresponsive to the idle mixture screw. Anyhow, as i said, oops. I should be shot.

tomorrow maybe I'll have a few more brain cells operating
all I can say tonight is, lol


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## earling (Mar 30, 2011)

Hey nice work on that old four barrel. I had a 389 pontiac once with a two barrel that squirted about a teaspoon of raw gas with the acc. pump. but stopped working one day. I took it all apart, for some totally unknown reason, I put a ball bearing I had lying around inside some orifice, and it all came back to life. That's all I can remember. It was a while ago. Pretty sure mechanics aren't taught this kind of stuff anymore

So...didn't see your last response... no, not soldering aluminium, there's a brass jet/tube with holes drilled in it, the solder held fine with a little flux first
But, wrong brass tube. 
If this works I'm going to buy myself a beer.


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## jdg (Aug 27, 2009)

The ball bearing is the accelerator pump inlet check ball...lets gas into the accelerator pump well, but doesn't let it go out the same way...forces it out thru the squirter holes. (funny long story about accelerator pump check balls...maybe later...)
The carb was probably a Rochester 2-Jet. I got a half dozen of them in a milk crate out in the garage, both 350CFM and 500CFM types...kinda rare these days.

Brass tube....gotcha...Makes a bit more sense now.

I gotta write this up while I'm thinking about it...'cause it's funny and the guy, Mac, is gone now. A victim of Methyl-Ethyl-Ketone before the Gov't would admit it was bad for you...
So, we (the whole shop, US Air Force B-52 Avionics shop at Ellsworth AFB) are all on midshift one night, nothing to do, sitting around doing paperwork, talking cars, about 20 of us, etc...
I get up to take a leak, the guys are all sitting around...One of the guys picks up a tiny ball bearing looking thing off the floor and says "what's this for?". Mac looks up and says "That's an accelerator pump check ball from a '74 Q-Jet". The guys all look around like he's smoking dope and all say things like "No way", "not possible", "you're full of shit", etc.
I get back from my leak break, the guys look at me, hand me the ball bearing, and ask me what it is. I take a quick look and without skipping a beat, I say it's an accelerator pump check ball from a '74 Q-Jet. They all start looking around, bewildered, laughing, carrying on, etc.etc.
As luck would have it, me and Mac had been messing around with carb's earlier that day. And, the '73 and earlier check balls were large and metal, '75 and later were small and plastic. Only the '74 types were large and plastic.
Don't know how it got on the floor. Maybe got dropped and fell in one of our shoes or maybe our pockets or something.
That's my semi-funny story for the day.

And if your solution does work, find an open store, buy yourself a 6 pack, go home and drink it while staring at your wonderous "new" vehicle.


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## earling (Mar 30, 2011)

still laughing at your '74 Q jet story. Good one. I'm sure I have a story or two along those lines (more wooden boat oriented, like, "that's a garboard from a '38 Meadowlark" ho ho ho, grab your sides) but right now I'm too stoked to think of any

So. I nailed the little fucker. This is indeed a great day. So, I finally started thinking clearly--out of the murk, so to speak, came a great light. This thing is a carb. Carbs run on jets. The thing is too lean at the top of the primary circuit. (I think what screwed me up is the double barrel business, and that horrible Chilton's drawing--crayon on newspaper... where da jets?) Long story short, I located the primary main jet (behind the float), pulled it out, and JUST HAPPENED to have a numbered wire drill bit for a Kawasaki carb that I jetted a while back, that JUST HAPPENED to be a little bigger than the orifice in that jet. So, I held it in my fingers, chucked that little bit up, and drilled a few thou. off the inside of that orifice. Squeak squeak. Put it all back together, cough all gone. Idles flawlessly at 700 RPM, pulls flat and clean from idle up to the secondary and beyond. Whoo hoo. 
Makes sense, I figured all that emissions crap must have stifled it a bit, and I'm letting in a fair bit more air, that undersized jet just couldn't deliver the goods. NO friggin idea what actual jet size I'm now running, but I still have the drill bit if it ever comes up


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## earling (Mar 30, 2011)

and I un-soldered the slow jet....


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## jdg (Aug 27, 2009)

Can't beat it with a stick...not that it would help.
But I gotta wonder what caused the problem in the first place. A problem downstream of the jet? A clog in there somewhere? Maybe the jet drilling covered up a completely separate problem?

Ahhh...screw it. It works. Good enough....


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## earling (Mar 30, 2011)

well don't forget all that emissions crap I pulled off of it. at least 4 vacuum lines, and the EGR pumping exhaust gas into the manifold. I can't keep track of it all, but I'm satisfied that it needs a slightly richer mix now that it's wild and free

There was also a steel plate under the carb with a sort of cup pressed into it that directed a high speed air flow across a huge port (that's now plugged). That thing was restrictive as all get out. I took it out. That alone could be cause for a mild re-jet. With motorcycles, all you have to do is put a hi flow air filter on them, and you have to go through the whole thing

Anyhow, I'm tickled. Getting an electric fan next. Going for MPGs.


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