Idle Mixture Screw

[Tailfin]

Ok I've touched on this before, but not much since I didn't care about it at the time...but now I do... The air/fuel mixture screw on the carb (88 lx) is umm...not accessible...and I see just a flat piece of metal where it is... I have chucked the fast idle cam/system completely out of this thing, and now it runs just fine except the pedal has to be held for a bit when it's cold (40 and under basically)...and I am thinking richening that a bit (along with putting an Accel super coil on :-D) would lessen this problem.

So...if someone could please inform me how do I get to that stupid screw lol...Thanks in advance.

[shepherd79]

you have to hold the pedal when it is cold?
well than your choke is not working. you have to check and fix it.
If you richen the mixture, it wouldn't help yeah to run on it is own in the cold weather. you probably have one or two system failures.

[Tailfin]

Nope, there is no friggin' way that choke is malfunctioning lol. I avoided that for a month before just buying a brand new puller from Majestic Honda, and the tabs are seating and adjusted properly. I could possibly consider a problem with the choke heater, but I think that's fine and it doesn't apply when the car first starts up anyway.

When it was a bit warmer, I tried adjusting it so it would open a little more on startup, and it ran rough, apparently lack of vacuum sucking the fuel down. The intake manifold gasket has been replaced, I've done away with most of the vacuum mess, and I've replaced the carb gaskets, needle and seat, o-rings, carb cleaner through the jets and such, etc... so I don't see how it could be a vacuum leak. Both fuel filters have been replaced as well. I don't think it's the fuel pump because it doesn't hesitate or bog when I push the pedal down...goes right up to 4,000 rpm and holds it with no surging or anything. So, the only thing I can come up with is it's just too cold...which makes the air more dense, so it will result in a more lean burn...which is why I wanted to adjust the mixture.

As for other system failures, well I've got fuel, the other one is spark, and I've checked the cap and rotor... Not brand new, but just slight wear from normal use...nothing to warrant stallage... I've checked the voltage running, and it's around 14...x the alternator off the list...and the battery is a brand new Optima...forget that as a problem also lol. Grounds are all polished as well. I don't have the cold distributor advance connected...but I did bump the timing a bit...Hmm, that should not be enough...I'll go check that now lol.

If it's above 45 or so, I can start it and not have to hold the pedal...which is getting rare here :-P. If it's held down for a minute...or a couple minutes if it's really cold, then it's fine thereafter. When it fully warms up, it idles at about 1500, which I know is kinda too high, but it's as low as I could manage to set it without the fast idle in there and still have it run. It gradually gets up to that idle speed as it warms up. When it's just warm enough to run steady, it's around 800. If I loosen the return spring (as mine is a ghetto throttle return spring stretched and such to a bracket I epoxy glued to the firewall :-D), the choke will open further when warm, which will bring that warm engine rpm down, but it will also get rough if I do that, again, seemingly from lack of vacuum...plus, then the choke plate doesn't stay steady. However, it does open noticeably more than on startup, so I still don't believe it's the choke heater. The float level is also set properly.

I don't really want to richen the mixture, but I would like it to idle cold without the assistance of the pedal or having it idle at a stupid 2500 rpm. It also makes sense that it could be a bit lean, otherwise, why would it spudder with the choke open all the way, even with it completely warmed up? It really just seems like this thing was designed by monkeys...

[shepherd79]

why didn't you connect cold vacuum advance?
you need it, connect it to intake manifold. both vacuum advances should be connected.
you can adjust all you want, but you can mess it up a big time. it is hard to get the mixture right.

[Tailfin]

Well, I read a bit of the how-to vacuum removal thread(s) on here, and leaving off the second advance was mentioned to prevent engine knock... So I gathered that maybe with all the junk removed, the vacuum was stronger to the one advance and affected it more or something... Well, plus, if doing that tends to richen it a bit. I did reconnect the advance, and I did notice an improvement, but still wasn't quite ready to run on its own.

I need to give it the morning after frost starting test to see the full effects here. All things being equal, I'll probably leave the mixture alone, but if need be, I was wondering just how to get to that silly screw if I did want to adjust it. At present, I just see flat metal in the way.

[shepherd79]

you have to remove the carb, unscrew the back plate (screws go from the bottom) and you should be able to get to the plug.