NissanDiesel Forums

Good Afternoon,

I've just had my latest project delivered. A '81 KC 720 Diesel - JN6SD06SXBW009226. It's pretty rough, but not too rusty on the cab and front end. (Edit colorful vehicle history) I'll post some pics and leave a link soon.

It'll need:

Seat(s) - replaced with seats from a ???- 1 shredded original in truck bed
RF Fender - looks to have been replaced, and then smashed again
Ignition Switch and rewire
Driver's door bushings
Possible engine elec harness and plugs
Pump bleed and filters
Valve Adj

It does have A/C. It'll be fun to work on. I was a Nissan tech for a few years and drive a 98 Frontier KC4WD right now too, but I haven't worked on a diesel since a CAT V8 at vo-tech in high school.

This forum appears to contain quite a wealth of information, I'm sure that it'll come in handy and I hope that I can return the favor in the future.

Andy

AStevens wrote:SNIP. I was a Nissan tech for a few years and drive a 98 Frontier KC4WD right now too, but I haven't worked on a diesel since a CAT V8 at vo-tech in high school.

This forum appears to contain quite a wealth of information, I'm sure that it'll come in handy and I hope that I can return the favor in the future.

Andy

Welcome Andy. Sounds like this old 720 fell into good hands.

How did you find this nissandiesel forum?

Welcome, Andy!

AStevens wrote:I've just had my latest project delivered. A '81 KC 720 Diesel . . .

You might want to put that in your Signature; just click on "Profile" at the top of any page. The advantage of doing that is that we can always see what rig you have, rather than trying to remember.

The '81 is a bit rarer than the more-plentiful '82. In particular, the secondary fuel filter is different, see this thread for the particulars.

When you get your pics, post a new thread over in User's Rigs.

Ignition Switch and rewire

While I probably can't do better than your local supplier for the switch itself, if you need anything to do with the lock itself, I work as a locksmith. I can code-cut, if you pull the code off the passenger door lock's tailpiece, or alternatively I have a complete used Ign lock assy (with switch) with two new keys (pulled from a Maxima, it bolts up fine) available.

Driver's door bushings

I didn't know these were able to be changed. I mean, reasonably easily. I've bought them as assys. from Nissan.

It does have PS and A/C.

That's a fairly rare combo. Philip's '82 is the only other one I know that has both.

Oops! Philip tells me that his '82 doesn't have PS. So, Andy, yours wins the "Most Hoses" award

Thanks for the welcome fellas.

Philip, I googled 'datsun 720 diesel SD' and the 720 MSN group came up. From there it was a short jump.

Al, thanks for the parts offers and info. My info about the door bushings was just an observation that it would seem reasonable to rebuild something like that - it'll probably just get hinges then. There weren't too many vehicles that ever came into the dealerships that needed that repair. The "rat" vehicles were sparse and usually got "blown out" with a big estimate.

That fuel filter post was already bookmarked. I found your workshop manual also - that'll be handy. I hope that I don't overwhelm your server trying to figure out what's what. I'm saving pages that I know that I'll use. That's such an awesome find and a wonderful resource. It's pretty funny to see that the basic setup of the manuals hasn't changed much since then. I remember always seeing them in the back rooms of the shops collecting dust. I doubt that there's any really big financial incentive for anyone to reproduce these manuals these days. I wonder if the Nissan folks can even get them.

I'll find out just how many functioning and/or installed hoses it has tomorrow. I didn't look this gift horse in the mouth too closely. It was pretty much "SD engine - check. Ok here's your money..". The guy was getting bombarded with calls and I just barely got it before the bidding wars started. It'll be funny to see if I can ice the top of this cake by eventually getting the aftermarket cruise control to work.

Photos of the beast.
It appears that I was cheated on the power steering bit.
I WANT MY $650 BACK! No, not really.

AStevens 720 photo album

AStevens wrote:Photos of the beast.
It appears that I was cheated on the power steering bit.
I WANT MY $650 BACK! No, not really.

AStevens 720 photo album

"Somebody" bypassed (or is assisting) the "lift pump" with that electric fuel pump. The heavy amperage glow plug relay has been "updated." Obviously ignorance should never be allowed under the hood with anything sharp. You DO have one of the rarer trucks having FACTORY a/c as evidenced by the flat air filter plenum and YOKE compressor. I would look high and low for another wiring harnass. The FSM harnass schematic seems to suggest there is only one Main Harnass for the engine room for both gas and diesel (not all connections used). HOPE this is the case! There is an optional speedometer having a tripmeter.

You would be MONEY AHEAD to get yourself the complete factory service manual ... look to eBay. They're still around, often coming from Australia. In the meantime, Al's web based electrical section will help you decide between repairing or replacing the engine room harnass.

Also, get in touch with this salvage yard. They've got a couple of 720s of various years! I get by this place on occasion.

Thanks Philip,

I'll keep your JY marked for memory as well. Thanks! It's always good to have recommendations. (Speaking of which, check out Yelp.com) I did some looking around last night for some things on Car-Part.com. It appears that there is a blue 720 Diesel in a scrapyard in Farmington, NM as well. There are some parts up the road near Safford, AZ as well.

I'll give it my best shot without replacing the harness. When I was an apprentice, I saw a Porshe 911 get a harness done...once. Man, that wasn't pretty at all. This one will be easier than that, but I figure that the more stuff that I can leave in place (not break), the better.

Al advised me on the manual as well. I'll get a search set up on eBay for an 81 w/Diesel supplement or an '82. Maybe I can make enough money from selling those crappy ford ranger seats out of it to pay for the manual. The guy chunked the passenger seat, but was nice enough to leave the rails and bolts.

Nissan wiring diagrams are much easier to read than the ones for the wife's Jetta. (Heck, the F14 radar/weapons wiring diagrams were even easier than the ones from VW)

What, you don't like current track diagrams?? Neither do I, but what can you do?

Philip: YOKE?

Andy: I have bought/sold three trucks to a friend, Peter. One very rusty '82 KC with A/C ("Bellingham truck"), whose drivetrain is going into an '86 720 non-A/C ("Marysville truck"). However, I also picked up a blown-up '82 KC ("Vashon truck") that he will be using for any fill-in parts.

The upshot is that either the A/C or non-A/C wiring harness should be available. The rusty '82 will definitely be scrapped (frame bad, cab bad, no title). The blown-up '82 is parts-only due to cab rust so bad the driver's door may fall off, but it may have a more appropriate wire harness for his conversion, which will be non-A/C.

All the A/C parts on the Bellingham truck are up for grabs, even though it's a runner right now. He pulled the compressor off to get better access to the alternator I had to rebuild (grrrrr. Wish he'd left the comp. in place!), so it's off already. He'll sell any A/C part off that rig.

He will likely sell the wire harness from one of them. However, the labor to do it right is going to mean that he's not going to pull it nicely for $10. I'd be happy to get his phone number to you if you want to discuss/cuss/negotiate about any of his parts.

All three trucks were "sourced" for him by me within the last year, so I know a bit about them, but I didn't keep any one of them for more than a week. All three trucks are on Marrowstone Island, Wash., and within 20 miles of me.

asavage wrote:Philip: YOKE?

YOKE (Yo-kee). Refer FSM 1982, pg HA-42 thru 48.

Now ... when I got that New.Old.Stock YOKE for my truck, oddly, it came in a YORK/Borg Warner box with a Datsun parts label on one end. I kept the old compressor and box the new one came in.

Andy, there was a bench seat in the non-KC models that is quite comfortable too, if'n you can't find decent buckets. The buckets I've seen have all been pretty bad. You see a lot of passenger side buckets installed on the driver's side for that reason.

i saw on a parts compatibility site, somewhere, that cateres to chop/drop/customizers that the 280z seats of the same year fit the 720 with out modification. (sorry for the terrible bit of vagueness) i haven't found a set worth trying to swap yet.

ocd, thanks for the tip. I would imagine that there are some junked z cars around here.

philip, the manuals, diesel and supplement are purchased and should be on the way soon. That $40 should save me some headaches.

We're 70 miles north of the border and there are ALOT of upholstery shops around here.

Al, I'm probably going to have to get your buddy's info. I broke into the harness this afternoon and some of the wires were so cooked, that there was only burned dust left where the wires once were. There are some heavy gauge white wires that go across in front of the radiator. It looks like those and some others wrapped close to them got reeeeally hot. I think that's alternator wiring and I found some alternator receipts from chucker's auto parts. This crackhead was a true genious.

It took me all of 15 minutes (and I was goofing off) to get the ignition switch removed. This guy did some strange wiring tricks under the dash and installed two switches on/off and a start button. Clown. I was pleased to find the key code is on the tab in the glove box along with the original owner's manual and some other junk.

Once some of this is done, it's on to the mechanical stuff. I'm concerned about the reasoning, or lack thereof, that went into the decision to assist/bypass the lift pump. Something about the sound of that part just screams blank check.

It's looking pretty ugly, but it's a go. The LW says that I can cherry it out as much as I want...within reason. I'm glad that I married her!

AStevens wrote:Al, I'm probably going to have to get your buddy's info.

Will send via email.

I broke into the harness this afternoon and some of the wires were so cooked . . .

I've done more of this kind of repair than most, and one look at the melted section over on the driver's fender, and I said to myself, "donor car". You don't rebuild meltdown wiring unless there is no alternative. I have made a lot of money over the years doing custom harness repairs, but it's not the straightest line to a professional repair.

There are supposed to be fusible links (more than one) that prevent just this kind of problem. See the top diagram here. Unfortunately, the links' connectors get bad -- the 5/16" spade terminals are notorious for losing their clamp strength after a while -- and when somebody diagnoses the problem, the links get bypassed. Which is fine, unless you ever need protection from a short!

It took me all of 15 minutes (and I was goofing off) to get the ignition switch removed.

You are either very good, and have the correct tools, or somebody has replaced the four break-away head bolts with std 5mm screws. Or maybe you removed only the switch on the back of the lock (two screws, after removing the column plastic)? I use a Dremel + cutoff wheel to cut a slot in the top of them, when I'm being professional, or a small cold chisel on the edge of the head when I'm not, to remove those screws. I actually have a collection of new 5mm screws & washers for when I replace them.

The Ign locks on all these era Nissans are fairly wear-prone. Subaru used the same parts in those years, and I do a fair amount of new-key-making and cylinder replacement on them. Use Tri-Flow every so often, it does help, and replace that worn-out key, it's just wearing out the locks. Generic Nissan/Subaru lock advice.

See also the Keys and locks thread.

I have become pretty proficient at fishing broken-off key tips out of ign. lock cylinders. Did another one on a Toyota Van Friday, made $15 in three minutes (I charge a dollar a minute, $15 minimum, to remove broken key parts from lock cylinders). The correct tools are the "key" to not damaging the lock. And you usually have to lift up the nearer wafers, one at a time, out of the way of the key chunk you're dragging back out the keyway. Old Toyotas, Geos seem to be the big offenders here.

I was pleased to find the key code is on the tab in the glove box along with the original owner's manual and some other junk.

That's certainly nice. The keycode sticker is not always present after about 1982, I've found, so the fact that yours is present is a bonus. However, if you didn't have breakaway bolts retaining the Ign. lock assy. to the column, it may not be the original Ign. lock assy.

I'm concerned about the reasoning, or lack thereof, that went into the decision to assist/bypass the lift pump.

The lift pump is rebuildable, cheaply. There's some nice pics of it here. Philip replaced his entire, and got the newer (less leaky) primer pump to boot.

The LW says . . .

Undefined reference alert. Pretend I can't use Google. Basic rule (in programming, anyway): do not reference a pointer until it's been defined, or undefined behaviour will result.

Yup, fuseable links are good stuff. Ignorance makes people bypass them evidently. Got the email. Thanks.

I'm good. I used to work flat rate. I've replaced a few elec parts only on some no-start sentras/maximas before as well. Two of the screws were replaced with phillips head screws though, so it was easy. Chisel, hammer, and small sidecutters to dig into the chisel marks - presto fixo! It's been screwdrivered and is junk as far as I know. My 90 hardbody had the code in the door too - dunno about my 98 Frontier though...all bets are off with that one.

LW=Lovely Wife There's no other LW that I'd marry