Samurai Idle help needed

schmors · 10-20-2009, 01:24 AM

I have an '86 Samurai that I got about a month ago. I cannot get it to idle right. When it starts up it idles really high, around 3k and then after a bit, goes down to maybe 1.5-2k and when its warm it dropps and putts and almost dies or dies. When driving along or touching the gas it runs great.

I just put a new (used) intake manifold into it cause I broke the old one over-tightening the PCV valve. It still runs almost the same. So I have the new intake manifold in and it seems all good except it is missing one place to plug a vacuum line into. It just doesn't have it, might be an older manifold or something without it. Its the line that comes from the middle of the canister to the manifold below the carb. Should I cap the line or leave it open or ??

Its the middle one in the picture:

87samurai_dunn · 10-20-2009, 03:39 PM

definately cap any vacuum ports that arent being used, as for the really high start up idle its just an adjustment, where the throttle cable hooks on to the carb theres a screw, loosen it a little until it idles where you like. then once warmed up use the idle up screw to make it idle where you like when warm

schmors · 10-20-2009, 10:33 PM

Wow that worked really well. I adjusted both of those screws and it seems to be working pretty well. However, when its warm, I can rev it high and then pull my foot off the gas and the idle will just drop all the way down and die rather than stopping where I have it set, around 1200rpm. When I rev it it just dies but if i hold it up around 1500rpm for a second then take my foot off the gas it will drop down and idle like its supposed to. Its like it just won't pull the right amount of gas to drop smoothly to an idle. Also, when it idles, it doesn't idle super smoothly but moves around tiny bit, but not terribly bad.

Thanks for your help, it helped a lot. I don't think its vacuum anymore but just the carb.

87samurai_dunn · 10-21-2009, 03:00 PM

if moving around when idleing that tells me theres a small vaccum leak somewhere...as for the dieing problem theres a syliniod on the carburetor that when you rev it, theres an arm on the syliniod that comes out to bring it smoothly down to idle...if it just dies this tells me that the syliniod isnt working... take the air intake off and rev it and look on the side of the carburetor facing the firewall and see if anything moves... if so it might just be the adjustment on the syliniod... if not then it is in need of replacement... on the stock hitachi carbs however if one thing goes wrong with them i recommend spending the 300 bucks and just getting a weber 32/36 kit from redline and replacing the carb

schmors · 10-21-2009, 06:44 PM

alright so I tried it out. Is it the circled thing in the picture that you're talking about? When its running, the little rod nipple thing sucks in, and as soon as I turn it off, it comes back out like it is in the picture. It doesn't seem to move at all when I rev it, just stays all the way in when it's running. Not sure if that is right? Also, it wouldn't idle at all with the air cleaner off, don't know if that matters?

Thanks for the help and patients

schmors · 10-22-2009, 12:40 PM

Okay I think I figured it out. When I took the air cleaner off yesterday, I forgot to plug the HIC valve under the cleaner back in. I noticed that when I was looking at that sloinoid and plugged it back in and not it idles! whoooo. So I think thats it? Might have a tiny leak somewhere cause it doesn't idle perfectly smooth, and it has to be around 1200rpm rather than 800 like its supposed to to idle well, but don't think thats a big deal. Now just have to get it smogged

87samurai_dunn · 10-22-2009, 05:04 PM

that was probly the rough idle issue...does it idle down now without stalling? but no the sylinoid that you circled is for the choke..the one i was talking about is on the side of the carburetor

schmors · 10-23-2009, 04:21 AM

yeah it does for the most part. It was running great and then it did the thing where it fell down and died a couple times, then stopped again and didn't do it until i drove it again after it was cool. Maybe it only does it before its all the way warm? I guess I need to drive it more and figure it out.
Okay, I think I know what you're talking about now. Is it right above where the cable goes where you can pull the throttle with your finger. Looks black rubber with a white point on the end? It would move around when i reved it. Move in when reved then back out more when idling ? Seemed to be working. Unless intermittent?

87samurai_dunn · 10-23-2009, 01:15 PM

thats the one...but its probly working constantly...its just a matter of adjustment and those carbs are hard to tune in perfect

schmors · 10-23-2009, 02:50 PM

Alright, I'll just keep messing with it. And run some more carb cleaner through it.
Thanks again for the help, it was very helpful!