81 Crew Cab Cummins project

[moparman89]

HELLO ALL, First of all this has been one of my favorite Dodge Sites!!
I'm gonna warn all of ya now,I'm known to miss spell things alot...its the keyboard fault... so bare with me.
I'm don't know a whole lot about wrenching on these diesels but I'm fixin to learn :eek:...so I'm gonna need lots of help from all of you on this project I'm going to attempt?
So heres the story....I have a '81 Dodge Crew Cab 4x4 318 4spd with dana 60's front and rear with 4;10s... its an ol ARMY truck that I'm wanting to swap in a '92 Cummins with 5spd, AC,and CC.
I have just purchased a BASKETCASE of a '92 Dodge diesel 4x4 regular cab,5spd, SRW....minus the front axle....well did have anyways...it was perfect for what I was wanting and cheap!
So here's what I know about this truck which isn't much,because it has been passed along to a few different owners...WHY I don't know,but I'm sure I will find out sooner or later...anyways..the pump has been turned up?...how I know this? well it pours the black smoke out anyways...as far as the injectors being stock or not I do not know,but want to find out? The turbo is a HX35? (I think thats what it said,I'll have to double check).
So heres the start of the project,first I wanted to get this thing drivable the way it was and get all the bugs worked out of it before I pull this thing and swap over to the CrewCab. I mounted a dana 60 under the front that I had lying around,got it going and got to drive it a few days ago,heres what I found out,it does smoke ALOT....black smoke that is, it seemed to run fine at first,then it started to run rough...this might be some air in the injectors do to it running out of fuel before I drove it...yeah thats another story! Anyways we are going to try to bleed them and go from there.
OK ...hope I haven't bored you too much so heres SOME of my problems. I Really don't know where to begin here..
1. This truck has to be started from under the hood by crossing some wires!
2. To shut the truck off....well you have to manually shut the fuel off.
3. The main problem I'm working with as of now is the wiring problems....I have NO outside lights....I have some interior lights working like the dome and the dash lights....the truck will not start by the key? nothing at all..... there is power to the fuseblock....as of anykind of power out of the cab I don't know yet?
I want to get all of this working...why you might ask if I'm swapping the motor out...well because I also want to swap the dash out also ,along with the AC stuff.
SO.....what do you think? any suggestions or comments (hopefully positive ones) ..will be GREATLY APPRECIATED!!
Oh yeah I'll post some pics of this jewel..

[moparman89]

Heres some pics....don't laugh too much..:hehe:

[moparman89]

[moparman89]

And heres the crew cab

[Tom Petroff]

Nice project!
Now I'm not trying to insult your intelligence but unless your really knowledgeable in automotive electronics, I would suggest shopping around for a MoPar service manual or the very least a Hayne's manual.
They have some wiring diagrams.
There is numerous circuits you will need to check.
Example, the start circuit is simple enough.
Power to key switch then to clutch interlock switch,then to starter relay finally the starter solenoid.
On the inj. pump you only need one wire to energize the run solenoid.
We haven't even started on the heat/ac,cold start,grid heaters,etc. yet.
So Get A Book.
Good luck with your build.
It will be a Great Driver.
TGP

[moparman89]

Thanks....yeah I have a factory service manual for a '91...looking for a '92 one though...I have been using mine alot for the wiring issues though,figured most of should be the same...as of today I have got alot of things figured out....it now starts by the key...have some lights....and everything working lights on the inside!!

[moparman89]

OK...its been awhile since I have messed with thing..got alot of the issues solved for now anywyas....so its finally time to get started on this long term project.....heres what I got done the FIRST day which was today...finally getting this project started..I will have PARTS FOR SALE off this 81 Dodge if anyone is looking for anything??

[moparman89]

Well I know its been a week now so heres the update ...OK...so I spent most of the past weekend working on getting the motor out...never thought it would had been such a pain in the @!@ to pull the motor out with the 4spd attached...I will never do that trick again...maybe it was just me I don't know but things just wouldn't clear....oh well I did get it out of there after spending most of Sunday working on that...took off some other stuff from the firewall on Saturday.....pulled the transfercase out today...so now what... :confused013:...well still plenty work to do...ok so I have some decisions to make now..am I gonna paint this thing or not....if so I would have to finish gutting the cab and deciede what color I want it....well I still have some other things to do next ..pull the bed off..pull the tank out..and what ever else I see..:thumbsup:
Some thing I would like to know...I will find out sooner or later....I have a 205 transfercase in this truck and thats whats in the 92 cummins truck..well thats what the sticker under the hood says....are they both the same or are the splines different? I counted my splines on the tailshaft I counted 23.

[BigMac]

Nice project, this is exactly what I want to do. That is a sweet looking '81!

Mac

[moparman89]

Boy what a fun weekend...but its not over yet...
I'm havin so much fun...the last time I had this much fun was when I restored a '69 Charger I had...just hope this project doens't take as long as that one did..
Well heres what I got done Sat. and Sun. ...removed the rear bumper,removed steering column,removed gas tank(of course I had to pump out 11 gal. first),then removed all four doors....what a day....gonna try to get the windshield and dash and seats monday?

[Bruce in BC]

Spline count

Cummins NP205 are usually 29 spline . Not sure when they went to 29 spline .
The transfer cases are easy to rebuild and pretty bomb proof .

[moparman89]

Cummins NP205 are usually 29 spline . Not sure when they went to 29 spline .
The transfer cases are easy to rebuild and pretty bomb proof .

Yeah I think I figured that out...the one on the 81 was a 23 spline I think...forgot what is was now...I was hoping they were the same,since the one on the 81 had only 75k miles on it....oh well.

[moparman89]

Well as of today got alot of things done,the window is now out...hmm..oh yeah NOT IN ONE PIECE...cracked it...looks like have to buy a new one now.....then I got the dash out,the heater box, oh and put the steering column back in so it would make it easier to move around....then decided to pull that truck out of the barn and move it to the other side...that will be put on hold for right now....moved the '92 Cummins truck in,and gonna start gutting it!
OOOPPS....

[Bruce in BC]

NP205 nomenclature

So swap the input shafts around . The parts will interchange without much work and the gears are a lot more forgiving than a rear end . While you are at it you get to see if a bearing is toast or water has invaded the case . Personally once I got it sealed up I would switch to synthetic oil . I am running a chev case with ford input , chev and dodge outputs . High milage does not mean much unless it was in 4 wheel drive alot .
Those stacks are sssssooo lame looking , I am waiting for some guy with 24 inch rims on his impala to add stacks .

[J10Mike]

Cummins NP205 are usually 29 spline . Not sure when they went to 29 spline .
The transfer cases are easy to rebuild and pretty bomb proof .

I know this is an old post. But, I thought I would add my 2 cents since I have been there.
All 89 thru 93 Dodge CTD NP205s from behind either the TF727 or A518 (46rh) auto trannys were 23 spline output shafts.
Only the NP205s from behind the manual Getrag 5 speed trannys were 29 spline.
I'm not here to embarrass anyone. I just want to clear up any disinformation that could steer someone in the wrong direction.

Mike