Nissan 720 idle adjustment. It revs and sustains about 4500rpm and won't come down.

Nissan 720 idle adjustment ENGINE, MT, SERIES. 2L SOHC (Z22) Fast Idle Speed (Off-Vehicle), Adjust Vehicle Powertrain Management Fuel Delivery and Air Induction Carburetor Adjustments Fast Idle Speed (Off-Vehicle), Adjust FAST IDLE SPEED (OFF-VEHICLE), ADJUST Fig. The throttle cable on engine side is adjusted for maximum slack: Air/Fuel Mixture: Adjustments Prior to adjusting idle mixture ratio, check and, if necessary, adjust ignition timing and curb idle speed as previously described. Genuine Nissan Part - 16144-73C01 (16114-73C00, 16144-0F301, 16144-86G01, 1614473C01) Mar 3, 2012 · The other part of the system is the fast idle cam which moves with the choke valve which allows the engine to idle at a higher speed during warm up to prevent stalling, this needs to be adjusted with the engine cold and at idle, so be sure you have access to this adjustment screw before starting your engine if it needs to be adjusted. I had a bad ground wire so I paid Stan's Electric in Indy to replace all my wiring so i don't think it's electrical. The first thing to do is not set up the idle speed, but to set the Idle mixture screw to lean best idle setting. The exhaust system is only a couple of years old and the truck otherwise runs pretty well, as far as a 30 year old pick-up goes anyway. It has a computer (under left seat) to adjust air fuel ratio. Seems the little timing loop near the firewall always give a poor result on all Nissan engines. Disconnect fan and TPS 3. I would definitely set the timing first but if you need this just to idle to set the timing you can repeat this after. Genuine Nissan Part - 16144-73C01 (16114-73C00, 16144-0F301, 16144-86G01, 1614473C01) May 3, 2021 · Adjusting new 32/36 DGEV per Redline instructions and with the supplied size 60 idle jet, I had the mixture out 2-1/2 turns to get Lean Best Idle. I locked the cam back, but found the idle ramping up again, after a 1-2 second purr at reasonable idle speed Mar 10, 2006 · Thanks guys! Also remember, you cannot set the timing properly IF base idle is messed up! For those people, here is another write-up I did on how to adjust idle. I have replaced the plugs, rotor, distributor cap, fuel filters and plug wires, but this hasn't helped. Oct 12, 2013 · After some more tinkering and investigating, I've narrowed down my issue to the fast idle cam. Since the Hardbody body had the Z24i from 87-89 also the first year Dec 24, 2020 · The idle speed screw increases and decreases the idle speed. Oct 24, 2014 · So this is semi connected to some of my older posts, i'm just tying it all together and trying to wrap it up. Adjust via . Feb 17, 2022 · Hello, for my Datsun 720 l20b automatic, I am struggling to understand how to adjust for an idle since when I have tried to adjust my carb( by the way a Hitachi DCH340) to run below 1000 rpm, it seems excessive for the idle mixture screw to be about six turns out. Oct 13, 2013 · After adjusting the idle screw and fuel/air mixture screw, the idle in drive and reverse was set to around the 650-700 RPM area that was advised by the EPA sticker under the hood. Sep 14, 2022 · There tends to be almost a full turn where it peaks so set roughly in the middle. You need a low speed tachometer to set the carb. Screw Idle Adjusting. Now that the AB valve is bypassed, I am able to achieve a much lower RPM. Sep 28, 2025 · This guide will walk you through everything you need to know about the Nissan Throttle Body Relearn, why it matters, and how to perform it successfully to restore smooth idle and reliable performance. Restart and rev 3 times to 3000 rpms 4. Genuine Nissan Part - 16144-73C01 (16114-73C00, 16144-0F301, 16144-86G01, 1614473C01) Nov 8, 2011 · The auto-choke on my old 720 didn't work and caused high idle all the time so I bypassed it by using a clothes hanger pin to hold the choke open once the truck got started, I'm saying that's the correct fix by any meansmine was a hack job. All 720-specific topics and discussion can be found here. 1980 Nissan 720. These carbs are so complex the fail over time with heat cycles. Hopefully, there's no broken linkage, etc to be found. Done complete tune up. ENGINE, MT, PETROL. I cannot get idle to come down at start up. Warm up and shut off 2. see pic 1 1. Gotta know if screws are a FUEL or AIR adj = most important! No description has been added to this video. It will be very normal to smell unburnt gas when the choke is on. Jul 25, 2010 · For some reason whenever I move the fast idle arm up the throttle goes to normal idle speed, but as soon as I press the gas the fast idle arm clicks up a notch and the throttle goes to 3000rpm. 4 runs great until choke comes off then idles rough. It idles high sort of when going down road have adjusted idle speed but hasn't helped. Mar 27, 2020 · Just bought 87 nissan XE w/ Z24 engine for a work truck. Repeat as many times as needed till you cannot improve the idle and it's at about 750-800. Also if I am getting things wron Aug 10, 2023 · Using a stubby phillips or flat screwdriver, turn the adjustment screw clockwise for idle down, counter-clockwise for idle up. Ive reset my timing (had a problem with Screw Adjusting. Oct 30, 2017 · You need to do a full tune up on the engine, including adjusting the valves. Can anyone shed some light on this Screw Adjusting. 0L F5 2WD. 1985 Nissan 720 Deluxe. But it still seems to want to die after it gets warmed up and tri Jan 13, 2010 · When I'm at a stop light (so I'm just sitting there, chillin in drive) the idle jumps from about 500-1700, but it's so rough the car physically moves. Dec 18, 2014 · 5. helps to have a vacuum gauge and a friend to step on gas if it won't idle. Genuine Nissan Part - 16144-73C01 (16114-73C00, 16144-0F301, 16144-86G01, 1614473C01) Screw Adjusting. May 21, 2020 · I think I remember reading something about adjusting jet sizes if you have to mess with the idle adjust screw that much. It's that simple! You've adjusted your idle speed. It starts easily, but instantly stalls, unless I keep the rpm high via the accelerator pedal. As for the idle-cut, that was my first guess as far as where to get the power from. This Fits Your Nissan 720 Part Number: 16144-23010Supersession (s): 16144-N0910; 1614423010 Fits 510, 520, 610S, 610W, 620 Diagrams and Kits What This Fits Product Types Services CARBURETOR Full Diagram #107 L20B 1975 - 1976 L20B CARBURETOR Full Diagram #019 L20B L20B CARBURETOR Full Diagram #021 1980-1986 Datsun 720 forums. Sep 10, 2010 · The idle speed would not go below 1500-2000 rpm no matter what- even with mixture adjustment turned all the way in and idle screw backed out. no luck Mechanic's Assistant: Is the rough idle intermittent or consistent? Customer: constant until it cuts off Mechanic's Assistant: What is the model of your '84 Nissan? Customer: 720 4x4 Mechanic's Assistant: Are you fixing your vehicle Apr 28, 2010 · My 1986 720 King Cab (manual transmission) won't idle. Screw Idle Adjust. Feb 5, 2015 · Re: NIkki adjustment Post by macgiver » Wed May 02, 2018 5:15 pm mac, Let's see carb adj (inside to out) = Float level ,jets , metering rod (springs/depth) +vacumm/power pistons ,linkage -WOT +"idle stop" , accelerator pump -start/stroke/duration , Choke , finally Idle mixture screws. Jan 7, 2023 · I’ve read as many old posts as possible about the low or rough idle but still can’t seem to get my 85 Nissan 720 (Stock Carb) running right. Check for vacuum leaks around intake manifold gaskets and hoses. Fig. Place fast idle screw on second step of Engine Mechanical problem 1989 Nissan Truck 4 cyl Two Wheel Drive Manual I need to lower my idle on my truck and cannot do in on the carb. Adjust mixture screw to find the fastest smooth idle speed and again turn the idle speed screw down. 1980 Nissan 720 Deluxe. I did this with the engine running to find the sweet spot. To restate ( and for those new to my topics ) I recently found out I was running on just one coil, fixed that problem and now it idles pretty high. runs fine at highway speed. The tuning instructions describe leaning out the idle fuel mixture until the idle worsens, then richening it in 1/4 turns until the idle smooths out, becomes worse again, and then finally placing the mixture 1/2 way between the two points for your 'best setting. 15 Fast idle adjustment. Do not attach any hoses disconnected during idle speed adjustment. Idle speed should have increased, so turn the idle speed screw back down. My 85 had the California emssion Z24. Aug 31, 2010 · I got my 32/36 Installed today, and i'm having some issues fine-tuning it. You also need a vacuum Nov 3, 2014 · Also, check your fast idle adjustment screw (visible from underside of the carb. Check the fast idle cam linkage for proper movement and ensure the idle speed screw is set correctly. Base idle for manual transmission GA16DE is 650 RPM, 750 RPM for automatic. ) I had a similar problem - choke fuse blew, didn't open fully and sat on the fast idle screw while running extra rich. Modified by mydato at 4:52 PM 2/11/2010 Customer: 1984 Nissan 720 2. I’ve checked all the vacuum lines (I think). Screw Idle Adjust (ISO). I adjusted the idle speed to be a tad higher. why do you need it to idle below 700rpm? i believe the recommended speed is 850? Screw Adjusting. Nov 19, 2008 · My 86. A persistently high fast idle in the 1985 Nissan 720 can stem from a sticking or misadjusted fast idle cam or an idle speed screw on the carburetor. The thermo element may be shot, as it never moved the mechanical Fast Idle Cam to the low idle position. It revs and sustains about 4500rpm and won't come down. Any Thoughts? 1986 Nissan Pickup Z24 Rough Idle and Throttle Bogging Fix Z24 engines often face rough idling and throttle bogging due to fuel or ignition issues. Nissan 720 2. Jan 15, 2012 · The screw you got marked in green down by the base is the idle speed adjustment and it should let you adjust it down to or below the 850 rpm idle speed but the fast idle cam needs to rotate off it's steps so the idle will go down as the engine warms up. tried carb, fuel pump, replaced intake. Going to open a new topic. more Apr 19, 2006 · Re: fast idle cam adjust Post by chulse1492 » Mon May 20, 2013 8:59 pm Thanks I think I got it dialed in. 3 Mixture adjusting screw seal plug removal 1. Nov 6, 2007 · Adjust to 10 degrees, nip the bolts up and check timing again to be sure. Race engine several times, then return engine to idle and measure CO percentage, which should meet the following Feb 28, 2013 · I've tried adjusting the mixture, the idle speed and even the timing but it still won't pass the hydrocarbons test. General tune up sequence, make sure the mechanical is right (compression check, valve adjustment) then do ignition, set timing, check spark plugs, their wires, other secondary ignition parts, cap and rotor, then work on the fuel system (carb). This is the idle mixture screw with the sealing plug removed Unlike EFI engines, carburetors have a choke that makes the engine run rich during the warm up period. Redline says more than 2 turns out would need larger idle jets I purchased 65 and 70 idle jets and here are the results: 65 - 3/4 turns in on idle scr Mar 14, 2021 · 1982 Nissan-Datsun Truck PL720 2WD L4-2187cc 2. Rough idle and bogging in the Z24 engine can stem from a dirty idle air control valve or clogged fuel injectors. This is a good time to check your Fast Idle Cam and Throttle position are up to FSM specs. I also always use a lead between coil pack 1 and the plug on all nissan engines with a coil pack setup. After about 8-10 minutes the choke shuts itself off. Mar 14, 2021 · It runs pretty smooth when I drive it, but when push in on clutch idle goes through the roof and won't idle down. First, turn in the mixture screw until the engine dies or runs worse, then back out the screw (recommend turning ¼ to ½ turn at a time). It was also offered with a SD diesel. 5 D21 has an ongoing way-too-high idle problem, getting worse lately. Any ideas? Jun 10, 2019 · The idle speed was adjusted as low as it would go, and it would not drop below 1000 RPM. Jul 25, 2010 · I am missing the fast idle cam, the spring that goes behind it, the spacer and the c clip ( There is a picture above in the original post that shows the exact 4 parts. check/adjust fuel air mixture. ' Nov 4, 2019 · A Nissan truck engine that is idling too fast probably can be fixed with a simple, inexpensive adjustment. It seems that the adjusting screw rests too high on it after it warms up. However I seem to keep running into problems. Make sure idle is correct BEFORE adjusting timing! 1. The federal emisson trucks have a normal Hitacji Carb. Apr 24, 2018 · Lower the idle speed and keep repeating untill you cannot improve on the idle quality and the idle speed is 700. The 720 was came with a L20B, Z20,Z22 or Z24 or rare Z24i in the USA. Engine wont rev over 3000 rpm. pc io29 td ygex uhvrt 2faotg byk gthu jarjg v6

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