New to trucks, Hello.

[breadbox]

started a build thread*mods can close or let it go off the page
Modified by breadbox at 7:03 PM 12/12/2008

[Desert Rat]

That truck will have a lot of miles left in her.

[breadbox]

Am I correct that the motor in the car is a z24?

I ordered a chilton manual for a couple bucks, so soon I will know a bit more.

I have never owned a carb'd motor. Is there anything I should know?

What are some common things to replace or look at with a rough idle on a 720?

[Desert Rat]

I believe it is a Z24.

Given it's age Id consider replacing plugs, wires, cap, and rotor to see if it runs any smoother. Then go looking for vacuum leaks on the old 20+ year old vacuum lines

[breadbox]

I bought a new distributor cap and rotor.

I go to replace it except it looks brand new wires too.

I replaced the cap and rotor anyway.

The truck runs good when it idles at 1500rpm. any less and it sounds like its about to run out of gas and stop. the truck shakes at idle almost like its running on 3 cylinders. I have a can of Seafoam, you think that would help?

Also are all the spark plugs necessary or what is the reason for 8 plugs on a fourbanger? and do they spark at the same time?

[Big-Bird]

There are 8 plugs on the that motor for emission purposes.

You should check the plug wire order and make sure all the wires are in the corrrect sequence. Same goes for the coils because there of 2 of em there under yer hood. Once you have the wires confirmed check the timing. It should idle smooth at 800-900 rpm.

I've put the wire order in here somewhere....I gotta locate it again.

[breadbox]

The Z24 engine has 8 firing ports; four on the intake manifold side of the engine,four on the exhaust side. They are numbered one intake (i.e. I1)starting from the rear of the engine to four(i.e. I4) at the front.This repeats for the exhaust side as well (i.e E1 to E4 ). The appropriate ignition wire plugs are stamped on the distributer cap that is I1 will be inserted into I1 stamped on the cap.

I looked at a 1073-1989 Datsun/Nissan 200sx, 240sx, 510, 610, 710, 810, maxima manual and it has the z22 carb motor in the book and this seems to be the correct firing order if anyone is interested.
Modified by breadbox at 2:50 PM 11/26/2008

[breadbox]

Today I looked at a couple plugs and they are gross. So friday I will pick up my new wires and exhaust plugs. I bought a new oil filter and 5 quarts of 10w40 high mile mobile. If the truck doesn't purr Friday I am ordering new coil packs.

Also how easy is it to swap out the trans oil and diff oil? I am thinking of using Lukas oil 80w90 or something, what ever stock is. What should I use in the trans? Also does the transfer case need new oil?

[Desert Rat]

Standard 75w90 or 80w90 gear oil is fine for the Diffs and Tcase. Transmissions typically require GL4 specifically - Napa carries this in 2qt jugs.

They're easy enough to do. You have a drain plug and a fill plug. Always remove the fill plug first so you can ensure you can get fluids in it after you've drained fluids out of it.

[breadbox]

I changed oil, using 10w40 mobile high mile. Still runs rough though, I don't know if I should have it taken in? How do you know a carb is bad?

did any of the 720's come with a solid front axle?
Modified by breadbox at 11:33 AM 11/27/2008

[breadbox]

Today I replaced the transmission fluid with 80/90 gl-4 "coastal" brand, Intake side plugs but not the wires because they already look new. Truck is still idling rough. While the air filter was off I inspected the vacuum hoses and they look fine from what I can tell, I may take time to replace them one at a time. What size ID hoses should I use for the vacuum hosing or is it a standard thing?(looks 1/4")

Should I replace fuel filter/s? I think I read the datty has 3 fuel filters one in the bay and two on the rail near the gas tank.

I hope the valves aren't bent but I wouldn't know what to look for so I will leave the valve cover alone.

I wish I had the manual but who knows when that is going to arrive.

[breadbox]

Also could I get some input on possible motor swaps. I am really worried that the truck will die and I won't be able to find another motor or head. I have an SR20 bottom end I could start building on or a running KAe that could use new belts and a cleaning.

[myrddin]

I was told in the past that 300+ was posible...

[Desert Rat]

The Z24 is a common engine and you could always look into swapping in a later one from a late 80s hardbody that's fuel injected. It would bolt right in - you'd need the ECU and wiring harness for it too.

Start looking for vacuum leaks. Get a can of carb cleaner and with the truck idling, spray around vacuum fittings and the carb (with the air cleaner on). If that idle changes or the truck dies when you spray a certain spot, you found a leak. A rebuilt carb could be a last resort.

No Nissan pickups in the US ever came stock with a solid front axle. The first 4wds were in 1979-1980 and they were like yours, but with a smaller 2.2 liter engine.

[breadbox]

I kind of want a small air filter can I swap out the carb for like a weber?

If so what would be a good size for the stock motor daily driven.

[Desert Rat]

do you have smog tests where you live?

That'd probably be my main concern on swapping carbs. If not, go for it.

I'm not sure what you'd need, but it would seem anything more than 350-400CFM would be serious overkill.

I'm sure Weber lists the different applications for their carbs.

[breadbox]

no smog testing where I live. I tried spraying the vacuum lines and seemed to change idle but not turn off the motor. So should I replace the vacuum lines just to do it?