Carb is idling too high

[82h]

hey guys, I have an 82 Honda Accord with a Keihin carb. the carb was idling weak and almost stalling , so a mechanic turned the idle screw up to 1000rpm to keep it a bit more stable; it was a bit more stable. Then i took off the carb to check the gaskets. When i put it back on , the car was idling very fast 1750 in neutral, 1100 in drive. the choke cable is completely loose, the throttle stop screw is out. I checked the hoses, and I can't find an incorrect correction or a vacuum leak. Any and all ideas are appreciated. I've been working on this for weeks now.

[Neuspeed87lx]

you know im dealing with the same problem on my 87.... it idles at likw 3000 and it wount go down.... cable is loose... and the throttle stop screw is out.... its gota be a vacuum leak or a hose connected incorrectly.... well thats probally what it is in my case.... im sure mike or one of the other carb gods can help u out

[Wipeout]

Have you tried turning down the idle screw?

[A20A1]

So you can't adjust the idle any lower?

I don't know much about the 82 keihin.
I'm not sure if it's the carb that dies when you tip it over... must have been only for the ccvc, lol I forget how many c's and v's there were.

[train]

on carbed cars, the idle circuit is VERY sensitive to vacuum leaks. when you took to the carb off, did you re-use the gasket? if so, did the gasket come in contact with anything that could knick or tear it? did you torque the carb down properly? maybe there was a piece of dirt or something stuck to the bottom of the gasket that you didn't see that would cause a vacuum leak. you may have something stuck in the metering jet or idle tube that causes a restriction in fuel flow. if possible, try to "borrow" someone's carb that you know for a fact is good. if you have a friend with a carb that fits your car and his idle and everything else is good, throw that carb on your car for a bit and see if the idle changes. these days, its cheaper and easier to replace the whole carb rather than fixing it.

EDIT: if your throttle stop screw was completely gone, i don't see how it would be idling high. if it was completely gone, the the throttle would come down too far since there's no stop screw to stop it, and it would idle very low, which could cause it to stall.

as far as the choke cable being loose, i'm not sure i can be of much help with that. i'm somewhat familiar with chokes operated by a heated bi-metallic spring, but i've never seen an accord's carb and how it works.

[train]

if there is no vacuum leak anywhere, make sure your throttle is adjusted properly. if your throttle is open slightly, your idle will be high. do you have a one or two barrel carburetor? check the throttle linkages and plate on the primary barrel. if its a 2 barrel, make sure the secondary barrel isn't misadjusted. it could be since the secondary doesn't get used as much. (unless you rag on the engine)

[82h]

thank you guys for you help so far. the idle screw and throttle cable are screwed loose/left loose to try to bring the idle DOWN. If I put them in normal position the idle will just increase, but it's already too high, so that's not logical. I asked the Honda dealer. They don't know how to fix it. I checked every hose for leaks. all good. the gasket the looks like a figure 8*somewhat* that i reused. I may have nicked it, but I doubt it. car still idles at 1700 in park, 1100 in drive. Has now developed a hesitation. when I turn around a corner holding gas constant there is a hesitation at the apex of the curve. If any of this helps. If just flipping the carb ruins it, is there nothing left to do?

[train]

you do let the car warm up to operating temp right? so its idling at 1700 RPMs in park at normal operating temp? if its idling there while the engine is cold, thats not really a bad thing. its supposed to idle a little high with a cold engine. i'm not surprised that a honda dealership can't help. they don't see much carbed cars at dealerships. you might wanna take it to a shop around your area that deals with older cars. see if you can find a shop that is run by someone around 40 yrs old or older. they should be able to help. a hesitation sounds like a fuel problem to me. is your float level ok? is you choke operating properly?

[A20A1]

well the idle diaphram is supposed to raise the idle when there is a drop in vacuum... and sometimes you can get to a point where the drop in vacuum from too much throttle causes the idle diaphragm to open the throttle even more and that will give you a high idle...4000-6000 rpm and such...

you want to idle off the throttle stop screw... not the idle diaphragm... the idle diaphragm is only ment to raise the idle when the car is under load from the lights or fans being turned on.

[canadian_badass72]

im having a similar problem about three times now my idle will go to about 2500 or higher and if i play with the throtle linkage enough it comes back down it just did it today when i started it up and took about three mintues of screwing around to get it back down any ideas?

[MaximumStrength]

I recently purchased a 1987 LX for $50 from a co-worker. One of its numerous problems was that the idle was way too high, despite all of the screws being backed completely out. Pretty much the exact problem you describe. In my case, the problem ended up being a vaccum leak from the two gaskets on the EFE spacer.

I tracked the leak down by spraying brake cleaner around the carburetor. When I got around to the backside near the base, the idle started climbing even more. As soon as I lifted the carb off the intake manifold, I could see where the carb spray was going past the gasket into a large vaccum port.

As soon as I replaced those gaskets and made some minor adjustments, the car ran 100x better than ever before.

-Rory

[A20A1]

The only large port in the EFE spacer is a coolant port, not vacuum.

[MaximumStrength]

Ah, thanks. In any case, it was going through that and into the other big port(I'm assuming that's air inlet?).


The only large port in the EFE spacer is a coolant port, not vacuum.

[A20A1]

oh you mean the ports for the primary and secondary barrels...

http://www.3geez.com/showthread.php?t=38161

The pics in that link should clear some things up.

[MaximumStrength]

Yes, the primary barrel is what I was thinking of. It also looks like some coolant may have been working its way through its gasket area as well.

In any case, those gaskets made a world of difference.

[82h]

i've never done a carb rebuild, but can't afford $400 for a new 82 keihin carb, is it hard to do right the first time, and are there any special tools needed? The most difficult thing i've done to my car is a valve adjustment. I read your post on rebuilding carbs, it didn't sound too bad. Should i gamble on doing a rebuild myself or just wait and save and buy the new carb? Also, can ANYBODY send me or tell me where i can get my hands on a sample set of instructions that comes with a rebuild kit? so I know what I'm getting myself into.

[A20A1]

you might want to check pauls shop manual... I'm not sure if it covers the second gen carbs or not.
http://www.3geez.com/showthread.php?t=25137
http://www.3geez.com/showthread.php?t=30792

[A20A1]

BTW what gasket did you see when you removed the carb? if it was a paper gasklet, it may be easier to cut your own out of a blank gasket sheet... just make sure you make all the needed holes in the gasket, some are fairly tiny.

The ruber ones you'll need to buy, though if you're really tight for money and can't find the rebuild kit, there are some gasket pastes that cone out of a tube... some are not good for use around gas or high temps so read the package... and remember steer clear of any holes when adding the paste cause when you tighten donw the carb the paste will smear and may clog a small internal passage.

[MaximumStrength]

I initially saw the rubber gasket, but I went ahead and replaced the other one while I had the carb off.