You need to adjust the automatic choke. Your choke may not be opening fully. There is a fast idle cam linked to the choke to keep the throttle open more until the engine is warm. The idle mixture screw is part 37 in the picture, but get the choke adjusted right first, and you may not have to adjust the mixture screw. See adjustment procedures at link beloe.
Repair Guides Carbureted Fuel System Carburetor AutoZone com
Hi,did you get your 720 fixed,I also have a 85,Ii replaced my engine with a Jasper engine,if you still need help let me know,here's a video of mine. 85 Nissan 720 4x4 2 4 Weber conversion
Whatever your problem is, I would guess that it happened after you began to drive it. I would consider looking for a vacumn leak. Plus, it would be helpful to know how the carb change affected the problem, as it does seem like fuel.
There are inline fuel filters under neather the truck body that may cause a problem, as well.
But I still feel that based on the limited amount of information, I would look for a vacumn leak. For example, if it has power brakes, a leaking hydrobooster can leak vacumn and throw of your air/fuel ratio. Vacumn pressure at idle should be 14.2, and at a higher idle should drop to about 12 or 11 inches of vacumn.
Bill
I am not familiar with this particular pickup, but you can start with checking the basics. If you take the line loose where it enters the carb, do you have fuel coming out when you crank the engine?(be careful to not spill fuel). If yes, then the carb float jet or input filter may be clogged. A carb rebuild will probably be in order. If there is no fuel at the input to the carb, check the fuel filter and fuel pump (this may be in fuel tank... not certain on that vehicle). Other possibilities are a crushed or kinked fuel line. I hope this helps you track down your problem.
If you have a diesel then the fuel shut off solenoid on the pump is not working correctly If you have a petrol engine with a carby then the idle solenoid valve is not working and allowing fuel to continue to be sucked past the idle circuit ande is ignited by the hot bits in the engine
Hi James,see my silver 85 Nissan on my icon,On your positive side at battery,you have a fusible link,about 4 wires,they could be burnt or melted and not getting power to where there going,had my 720 for 19 years,have replaced mine twice,you have to get from dealer,22.00.Here's a link to NISSAN FORUM,It's 720world.com I am a member and you can join,it's free,you can sell,buy parts and post what you need help with,very cool place,also see pictures of nissans,check mine out,it's awesome.Here's a video of my 85 4x4,on my weber conversion,you may see the fusible link at positive side of battery,a bunch of wires,need more help.let me know,here's a link to video.
Bent synchonizer ring. Contrary to what some may tell you, do not park a manual transmission vehicle IN GEAR. This is even worse, if you park on a hill. If the emergency brake is not set to take the weight (force) first, then the gear synchonizer rings can be bent causing shifting and noise problems later. Set the parking (emergency) brake first, shift into Neutral taking your foot off the brake pedal to let the emergency brake take the weight, shut off the engine and then shift in to gear if you want to leave it IN GEAR when parked. Try draining your Manual Transmission oil and replace with either a top quality Hypoid Gear Oil AND Slik 50 Gear Oil Additive or simply use Castrol TAF-X Gear Oil. Remember to clean the magnetic drain (sump) bolt as they are usually covered with fine metal filings. A tooth pick works great on the edges of the magnet. A short piece of clear tubing 3/8 inch diameter will make the refill job easier when fitted securely to the nozzle end of a gear oil container. Place the vehicle on level ground and FIRST remove the square refill bolt with a ratchet (if punched inwards) or spanner (if outwards). THEN, drain the transmission oil. Some sumps (drain plugs) use a regular bolt and others a square hole that you can use a ratchet with suitable size adapter. Many are 1/2 inch square, so if you have a 3/8 in ratchet you need to get a 1/2 inch adapter for it to open the drain plug before you start. If you can't physically slide under the car, you need to place it on JACK STANDS or better still, a Hydraulic Lift. Following the manufacturer's instructions for jacking your vehicle and placing JACK STANDS. Note: As an extra precaution consider keeping the car jack raised to the same height as the JACK STAND on the side of the vehicle that you will be crawling under just in case something slips. It doesn't take any more time as you will still need to jack the car up a bit to remove the first jack stand and then begin the lowering process one axle at a time after you're done.
When your engine is CRANKED the voltage/curent feed to the starter is very high that the IGNITION SYSTEM DOES NOT GET THE REQUIRED VOLTAGE.
When the car is pushed it will start immediately as the full voltage is applied on the coil for a good spark.
So you must check the battery, the battery terminals, the ground connections and the starter motor. If the starter motor has worn out bushes/brushes/pinion then it will drain more current as the starter is turned.
Since there is no firing it is only evident that there will be flooding. So remove plugs and flush out before the engine is cranked.
Best bet for a replacement carb would be a weber 32/36..Part # K646 . It has everything in the kit for replacing the stock carb. Block off all the emission vac ports.
If you try to recharge the A/C using the old R-12 refrigerant it would be expensive because you would have to take it to a professional to have it done, but they do sell do it yourself kits to convert the old R-12 to the new R-134a. Walmart I believe sells the kits and probably any auto parts store. Assuming there is nothing wrong with the A/C unit. You will need to have a professional evacuate the old R-12 refrigerant first because R-12 and R-134a don't mix and it is illegal to vent it into the atmosphere.
Repair Guides Carbureted Fuel System Carburetor AutoZone com
