Breadbox's 720 Thread

[breadbox]

I decided that I am going to have to do some work on this truck, so here is the documentation.

In December 2008, I bought a 1984 Nissan/Datsun 4x4 KingCab.

It was purchased new by an older man who gifted it to his grandson last year. The motor is a 2.4L, napZ24. Just under 116,000 on the clock.

Side

Gate

Front

Motor

Carb Z

Interior

Miles

I have decided his name is Zombro. I got zombro and drove from Newport News to Virginia beach with a shaky idle but drives solid. He has problems idling at 700-800 which is what is was idling at. I adjusted the pedal after a tune-up to idle at 1000.

When I turn sharply I heard a loud noise but I kinda think its a diff, but not sure.

I looked at a 1973-1989 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.

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 distributor cap that is I1 will be inserted into I1 stamped on the cap.

What kind of oil for my transmission and differential?

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.

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?

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.

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.

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.

no smog testing where I live. I tried spraying the vacuum lines and seemed to change idle but not turn off the motor. I pushed all the hoses together at the t joint or which ever air port it was connected to, and then sprayed again and it doesn't change idle but also didn't fix my idle problem.

So should I replace the vacuum lines just to do it?

Modified by breadbox at 4:33 PM 6/8/2009
Modified by breadbox at 11:57 AM 10/19/2009

[breadbox]

Today, Moved my original thread from NICO trucks to ODPL.

I bought a bucket, car wash, couple sponges, and some turtle wash to clean her up a bit.

I bought a new fuel filter and will be replacing that soon, along with vacuum lines.

[phlebmaster]

Thank you for moving this here. It is nice to see some activity coming to ODPL.

Nice truck too.

[PEZi]

on these old trucks... replacing the vacuum lines always helps.... if it fixes it you'll only know by doing it

i had some crazy idle problems and i replaced all the lines and it was good as new

[phlebmaster]

on these old trucks... replacing the vacuum lines always helps.... if it fixes it you'll only know by doing it

i had some crazy idle problems and i replaced all the lines and it was good as new

That is the first thing I do when I buy a new...old rig. Vac lines, filters, and oil change.

[breadbox]

Yay! warm in Feb. so I washed Zombro this morning and took a good look around the paint and making a list of things to fix.

Dirt is dug in the paint and there are lots of rust spots forming.

After I gave him a bath I replaced the fuel filter.

blurry picture of dirt in snowflake patterns in the paint

Rusty seam Driver side rear bed

Rusty seam pass side rear bed

Bent rear bumper

Messed up pass fender

Battery with many wires coming off of it

Closer in the wirey mess

What is that white thing?

This white thing

found it... its called a vacuum control valve (also known as a vacuum relief valve)

*later model spark timing systems are equipped with a vacuum control valve which is installed inline with the venturi vacuum line between the carburetor and the distributor. when the carburetor venturi vacuum exceeds the preset value, the air is bled to the distributor vacuum line, retarding the spark time slightly.*

Modified by breadbox at 4:35 PM 6/8/2009

[breadbox]

Best way of going about fixing up the rusty bed? I could take it apart right?!

I figure the rest will get sanded and sprayed with rust preventative then lay down new white paint.

What is the least expensive welder I could get away with to fix up the bed or should I make a new friend with a welder?

[phlebmaster]

Best way of going about fixing up the rusty bed? I could take it apart right?!

I figure the rest will get sanded and sprayed with rust preventative then lay down new white paint.

What is the least expensive welder I could get away with to fix up the bed or should I make a new friend with a welder?

The best way is to cut out the bad metal and weld in new panels. Not the easiest way to go.

Sanding, old paint removal around those spots using a quality rust remover and a good wash is the fastest way.

You can find welders on CL and in your local Harbor Freight stores pretty cheap...try to make a friend first.

[PEZi]

The best way is to cut out the bad metal and weld in new panels. Not the easiest way to go.

that's what i did

[breadbox]

Sounds like a good project.

Can anyone tell me what the white thing in the picture is?

[PEZi]

got me... i've wondered the same thing for years

let me see if it is in my book of stuff... i'll post back soon

[breadbox]

I have a chilton manual but I can't read* edited
Modified by breadbox at 2:15 PM 2/10/2009

[PEZi]

found it... its called a vacuum control valve (also known as a vacuum relief valve)

*later model spark timing systems are equipped with a vacuum control valve which is installed inline with the venturi vacuum line between the carburetor and the distributor. when the carburetor venturi vacuum exceeds the preset value, the air is bled to the distributor vacuum line, retarding the spark time slightly.*

[breadbox]

Nice thank you.

[PEZi]

no problem... so by this description would you say that by removing (the white thing) the spark would never delay??? and wouldn't that be a good thing???
Modified by PEZi303 at 6:15 PM 2/10/2009

[breadbox]

I am not quite sure but yeah?

[2kredz3]

I have essentially the exact same truck. on the bed i cut the rust out sanded then took the inside of the bed apart and glued cardboard on the inside. when that was dry i used bondo to make the outside smooth.



this is what mine looked like before i did the repair.

[YEPEE]

back in the old days, those lower bedside panels where available separately

[2kredz3]

no problem... so by this description would you say that by removing (the white thing) the spark would never delay??? and wouldn't that be a good thing???

Modified by PEZi303 at 6:15 PM 2/10/2009

i have removed mine. . .it sucks in a small way because now if the temp changes outside i have to adjust the timing manually. i am going to see if i can find it and re-install it

[breadbox]

Is there supposed to be a cap on it or some sort of filter?

[2kredz3]

Is there supposed to be a cap on it or some sort of filter?

no, the vacuum comes from the part sticking up out of the intake manifold based on temp it opens and bleeds air from the air filter housing.

[breadbox]

How much does it cost to rebuild a carb? Or is that something I could do myself?

I feel like my truck isn't getting the right a/f ratios or something at idle but it does at 1000rpm, but definitely lopeing at 800rpm. I may still have a vac leak somewhere, but IDK.

I might start walking through my hood everyday til I see someone working on/rebuilding/restoring a carb'd vehicle in their garage, then see if i can get some help and have a new friend.

[PEZi]

i'd say just get the weber... even a used rebuilt one should be pretty cheap and work awesome

rebuilding is something you can do yourself but there are a lot of ways to do it wrong if its your first time so if you do choose to... find someone who knows how to help

[Supererogator]

I have done a handful of carbs, and they aren't too hard. It is mainly the small pieces that get lost that have been an issue. Like a little ball-bearing like float. Having a buddy who has some clue will help, but a nice tidy dis-assembly and reassembly usually does the trick and most carbs have a "rebuild kit" available for cheap. If you have a bit of tech know-how, you should be fine. The replacement Webers sound kinda good anyway.

[breadbox]

Did we ever decide what the correct stock replacement weber is?

[breadbox]

I was also wondering what wheels I could just throw on my truck. The rears don't seem much of a problem, the front have the hubs( i think to lock them to drive) so I was wondering do I need 4wd front wheels?

[breadbox]

I just made an ODPL photobucket. In case you need to host a random quick picture of a 720.

login:name - ODPL720//pass - napz24

[layedoutb2k]

truck looks real good. a pretty solid truck to start with. i know a 32/36 weber works real good for smaller 4 cylinders(what most people swap onto L series). not too sure if it might choke the z24 on power due to a little big bigger displacement but should give you good gas mileage.

[Cricket066]

I used 6 lugs Wheels off a chevy 3/4 4x4 and put 31 LTB Swampers on them and it handles them faily well

[breadbox]

Well he died during this busy week. I think its the fuel pump. Then yesterday I was playing soccer with my dog and stepped on a root wrong and I sprained my leg horribly. I hope I can get my truck working and be able to shift still.
Modified by breadbox at 9:38 AM 3/31/2009