1983 720 4x4 King Cab Build Thread

[Jon's AD3 720]

Just thought I would start documenting the changes and progress I am making on my truck. I bought the truck 6 months ago not intending to do much to it because it was going to be for hunting, and getting out in the trails and mud, but as you all are aware that when you start tinkering with things, upgrading parts,  cleaning the truck up, and removing rust etc. you become addicted, and pretty soon it’s all you want to do. Which is probably why my wife wants to torch the truck and push it off a cliff.

Hopefully the thread will be worth a look, and hopefully I can get some help from you guys when I have questions. Thanks.

 

Truck Info:

It has 196K miles on the truck. When I bought it, the PO had installed a completely rebuilt Z24 engine which had 1,700 miles on it. New timing chain, chain guide, new gaskets all around, rings, Webber carb(not sure which one), all new clutch, break lines and maybe more that I can’t remember.

Since buying the truck I have mostly just done cosmetic upgrades.

New (old) seats (2000 ish dodge Neon) they are too tall ?

New stereo and speakers. PO cut speakers into the cab pillars.

Replaced blinkers, parking, and break lights with LED bulbs. Now they all work.

Painted front two fenders and passenger door to match (as best they could) the rest of the truck. Truck is no longer 3 different colors.

New plugs and wires, which cleared up the rough running motor. Glad it was not a head gasket.

 

Things I need to address in no particular order:

Horn does not work

Windshield wipers on interval only go half way then pause in the middle of the windshield for a few seconds and then go a bit more and then another pause and so on.

Rust in the floor pan where the cab bolts to the frame.

Dome light and door open close switched.

After the cab is dried in I will install the carpet that I ordered for it. Random bolt holes and a few rust spots. Going to need to cut out some rust and patch weld in a replacement.

I found three 720s that are the same age that a guy is going to sell me cheap, and I need to rob parts off of them AND maybe build another truck out of the three.  Brush guard, KC lights, bumper, seats, canopy etc.

 

 

 

 

new lights

 

 

 

paint

 

 

 

 

badges. reversed the colors because sanding was easier than masking. i was planning on reattaching them with double sided tape. any other suggestions?

 

 

 

 

sometimes the only time i have to work on the truck is at night, and the kids rooms are right above the garage. so that means i'm outside in the back yard with a head lamp.

new BT stereo.

tail gate works

parts trucks i plan to buy. seized motor in this one.

 

there are two trucks like the one below. only one pictured. the other one is in better shape. and he says it runs.

 

let the fun continue. thanks.

 

-Jon

 

 

 

[Blakely]

Awesome looks fantastic 

[bottomwatcher]

Looks great! Looks early 83 ish. Build date? A lot of those later trucks parts don't interchange with the earlier ones but you can make a good on out of the three. Now the wife? They see each new project dragged home as "competition" for time, money and listening to them time so good luck with that! Keep us posted you make good progress.

[datzenmike]

12 minutes ago, bottomwatcher said:

  Looks early 83 ish. Build date? A lot of those later trucks parts don't interchange with the earlier ones but you can make a good on out of the three. 

 

It's an '83 model year but made (build date on driver's door tag) between July and November '82. This was when the hood with the louvers stopped, the retirement of the Z22 for the Z24 engine, the square dash instruments for round and the front disc brakes from non vented to vented with larger calipers and more.

 

This is the first one I have actually seen.

[Jon's AD3 720]

It was manufactured August of 1982

[datzenmike]

Bingo.

[DrvnDrvr]

It's got that gorgeous bed with the outer bed cleats,horizontal tail lights and DATSUN stamped on the tailgate!!!!

A true rare find.

 

[datzenmike]

Again this also changed to the vertical lights in the corners of the beds and the DATSUN was replaced by NISSAN on the tail gate in November '82 but retained the outward facing bed lip through '84.

[Lockleaf]

Very clean truck.  Take a block from one of the yellow ones and fix up that copper beastie too

[Jon's AD3 720]

that is what i would like to do, and then use the other two as parts trucks. unfortunately i think the copper truck is the one without a title. ill see if the guy will work with me on getting a title, or i may just swap VIN tags if i run out of options.

 

does anyone have an idea of how i would sort out the windshield wiper issue i mentioned? on the interval setting they move about 12 inches and then stop for 4 seconds and then move another 12 inches and so on.

 

got the finders and passenger door back on. the color isn't a perfect match, but its much better than it was. in hindsight, when they were matching the paint i should have had them match paint from the side of the vehicle instead of the hood. the hood has had more direct sunlight and has faded more over the years.

 

 

 

 

this is the worst of the floor pan rust. where it bolts to the frame both passenger and drivers side. i will remove the sound dampening material (hopefully i wont find anymore rust when doing so) and cut out the rusty area and weld in a patch. has anyone had a similar issue and performed a similar procedure?

 

 

 

 

 

 

 

 

 

[datzenmike]

Agree, very thin, black double sided tape on the emblems.

 

Wipers.... I bet when you turn them off they don't park at the bottom?

[Jon's AD3 720]

that is correct. when you shut them off that's where they stay.

[datzenmike]

Find the wiper motor plug out under the hood. My guess is the park circuit is not working properly. The park is separate from the rest of the wiper switching.  Find the black wire and ground it... see if that fixes the problem.

[Jon's AD3 720]

ill give that a look Monday which is my next day off. i work weekends, so having 4 days off a week will hopefully allow me to get plenty of work done on the truck. ill let you know what i find out. thanks.

[datzenmike]

The wiper is powered any time the ignition is on. Speeds and the delay are a selected ground which completes the circuit. When the switch is turned to off (there is still power to the motor) and there is a path to ground that is interrupted when the wiper reaches the bottom of the windshield. This is how the intermittent delay works... it briefly turns the motor on to get it off this dead spot and it reverts to the park mode and stops at the bottom of the windshield again and waits. Because the motor works we know there is power to the motor. The ground is necessary for the park to work.

 

If grounding the Black wire does not work the problem is inside the wiper assy.

[Jon's AD3 720]

awesome. thanks.

[Madkaw]

4 hours ago, Jon's AD3 720 said:

that is what i would like to do, and then use the other two as parts trucks. unfortunately i think the copper truck is the one without a title. ill see if the guy will work with me on getting a title, or i may just swap VIN tags if i run out of options.

 

does anyone have an idea of how i would sort out the windshield wiper issue i mentioned? on the interval setting they move about 12 inches and then stop for 4 seconds and then move another 12 inches and so on.

 

got the finders and passenger door back on. the color isn't a perfect match, but its much better than it was. in hindsight, when they were matching the paint i should have had them match paint from the side of the vehicle instead of the hood. the hood has had more direct sunlight and has faded more over the years.

 

 

 

 

this is the worst of the floor pan rust. where it bolts to the frame both passenger and drivers side. i will remove the sound dampening material (hopefully i wont find anymore rust when doing so) and cut out the rusty area and weld in a patch. has anyone had a similar issue and performed a similar procedure?

 

 

 

 

 

 

 

 

 

Just finished this fix. It’s more involved than you think. Your cab mount is under that sheet metal and it’s probably bad. There’s two layers of metal, thicker metal that the cab mount bushing sits against sand then the floor metal. 

 

[Jon's AD3 720]

Well I figured there was something thicker than 12 or 13 gauge steel down there, but I haven’t dove into it yet. I know a few good fabricators and have access to  metal so let’s see what happens ?

[Madkaw]

It’s not thicker than 12 gauge , but it’s the top of the cab mount brace . 

Depending the extent of the rust it might be damaged into the inner rocker

 

 

Edited January 6, 2019 by Madkaw

[Jon's AD3 720]

a few updates. working on the floor pans. wired and installed new speakers in the toe kick. did these trucks come stock with only two speakers in the toe kicks? rewired the dome light and door open sensors.

 

finally got the original service manual

 

 

does anyone have a good method to seal/fix these pin holes at the base of the toe kick?

 

 

once i get it dry and rust free i will paint with rustoleum and install the carpet.

[Madkaw]

I would get some Por-15 rust paint , it will fill those holes and provide protection . The. Seam seal everything 

[]2eDeYe]

If you are fixing the floors anyways I would cut that out and add new metal. 

 

Great looking truck BTW B) 

[Jon's AD3 720]

I was a quart low on oil the other day so i put a quart of Lucas heavy duty oil stabilizer in instead of oil and now my engine is smoking a lot more than it used to ( from the exhaust). i have the Z24 that was rebuilt in the last 3k miles. should i not have used the Lucas? is there a reason why the Lucas and the smoking would be related and occur at the same time?

 

Also, i don't know if it is related, but i think i developed what sounds like an exhaust leak coming from the manifold. this also started the same day that i added the Lucas stabilizer. are these all related, or does the smoke and exhaust least have nothing to do with the Lucas?

 

i haven't done a soapy water test on the exhaust yet, and i haven't done a compression test since the symptoms occurred either. any ideas or thoughts on the Lucas Oil?

 

i don't know if this info sheds any light on a potential solution, but my compression from the front of the engine to the back was 146, 126, 141, 142 before these symptoms.

 

the engine purrs smoothly at idle when it is warmed up, but you can still hear the "ticking" sound that i think is the exhaust leak. when i accelerate the sound gets louder and more frequent. the sound does not go away from thermal expansion as the engine warms up either.

 

any ideas? thanks.

[datzenmike]

Never never never use oil or gas additives... ever. Engines will run perfectly on 3 qts until you can top it up properly.

 

 

Can't see how this would cause smoke unless the oil was actual full and you added too much and the crankshaft throws are splashing it onto the cylinder walls. Check the oil level engine of and on level ground. Make sure dip stick is not damaged and seating properly. With luck all you have to do is drain a quart out.

[Jon's AD3 720]

inspected some more. my oil level is fine. and it isn't smoke coming out of my exhaust it's steam.  i have coolant coming up out of the rear exhaust manifold gasket when i start it after it sits warm for a few minutes. i also have milky oil stuck to the oil cap. so i have water in my oil, i have a bad exhaust manifold gasket for sure, I have a bad head gasket, and i may have a bad/cracked head letting water into the exhaust and oil.

 

am i diagnosing this correctly? do i have a bad head gasket for sure? Is my next step pulling the head straight away?  Shit!   😕