New Owner - 1st Question

[ro23j]

I heartily endorse what Mike said above about servicing the electrical connections.

When I put my old beater back together, I had the advantage of having an NOS set of harnesses in their boxes.

Still, I Ox-Gard’ed every single connector, and sealed the outsides with di-electric grease.

Thanks for responding, I plan to use di-electric grease on the connectors.
Jim

 

[Fastback67]

I spent most of one day removing and cleaning all of the under hood grounds and opening the charging system connectors and cleaning those as well, but it did not change the voltage at the regulator.

Jim,
You want to clean up ALL of the connectors and plugs out under the hood. Even things like your Water In Fuel sensor, Manifold Heat Sensor, etc. are tied to the Charging system.
I should also mention that the location I've given for the splice in the wiring harness is related to the 1990 mode year... Other years may be different, I can't really say since?? The Factory Service Manual is the place to look in that case.

 

[ro23j]

Jim,
You want to clean up ALL of the connectors and plugs out under the hood. Even things like your Water In Fuel sensor, Manifold Heat Sensor, etc. are tied to the Charging system.
I should also mention that the location I've given for the splice in the wiring harness is related to the 1990 mode year... Other years may be different, I can't really say since?? The Factory Service Manual is the place to look in that case.

Another question before I tear into the harness. Please correct me if I am wrong, but it seems to me that there is no need to uncover the splice, but instead cut the blue wire that goes to the regulator, and wire the relay to that point. Does that make sense or am I missing something?

 

[ro23j]

Jim,
You want to clean up ALL of the connectors and plugs out under the hood. Even things like your Water In Fuel sensor, Manifold Heat Sensor, etc. are tied to the Charging system.
I should also mention that the location I've given for the splice in the wiring harness is related to the 1990 mode year... Other years may be different, I can't really say since?? The Factory Service Manual is the place to look in that case.

I looked in the FSM as suggested and I found the splice in same location as the one in your photo. Time to start wiring the relay. Thanks, Jim

 

[Fastback67]

...it seems to me that there is no need to uncover the splice, but instead cut the blue wire that goes to the regulator, and wire the relay to that point. Does that make sense or am I missing something?

You need two blue wires from the splice. Look at my diagram on the previous page.
You can cut & split the one blue wire coming from the VR... the end coming from the splice can be used to activate the pulling coil on the relay. The other end of the blue wire (the side coming from the VR) will need to be tied to the other blue wire coming from the alternator and then tied to the output of the relay. Again, refer to the previously mentioned diagram, it's all there in the Before & After illustrations.

 

[ro23j]

You need two blue wires from the splice. Look at my diagram on the previous page.
You can cut & split the one blue wire coming from the VR... the end coming from the splice can be used to activate the pulling coil on the relay. The other end of the blue wire (the side coming from the VR) will need to be tied to the other blue wire coming from the alternator and then tied to the output of the relay. Again, refer to the previously mentioned diagram, it's all there in the Before & After illustrations.

Got it, both blue wires.
Another question: will the "low voltage" end of the cut be enough to close the new relay?

I got the relay installed and wired to the battery and ground, have not yet cut any existing wires.

Thanks again,
Jim

 

[Fastback67]

Another question: will the "low voltage" end of the cut be enough to close the new relay?

Yeah, it should be fine...

 

[ro23j]

Yeah, it should be fine...

I completed the wiring as shown in your diagram and the modification solved the problem. I now have full battery voltage to the regulator and while running, 14.25 volts across the battery. The hardest part was soldering the wires (my old bones and joints do not allow me to get in positions that used to be no problem). This post was great help to me, especially being electrically challenged. I have owned this truck since 1993 and don't want to give up on it. Thanks for all the replies.

 

[Crank]

I just took my "new to me" truck out for it's first real test drive on a major Highway.
Engine purrs like a kitten, but the best speed I could muster was 55 MPH on a flat straight stretch of road? The truck has 3.07 gears and stock 235/85/16 rubber, so that puts me in the 1700 - 1800 RPM area if all else is correct. I don't have a Tach in the truck, so this is just an assumption. I'm guessing it's time for a new governor spring, but this is my first diesel, so what do I know.
Any Thoughts?

Basic vehicle specs can be found here in my opening post over in the new guy section... https://www.turbodieselregister.com/threads/260567-1st-Diesel-1st-Post

You don't live in Nevada. That is your "Governer".

 

[Fastback67]

I completed the wiring as shown in your diagram and the modification solved the problem. I now have full battery voltage to the regulator and while running, 14.25 volts across the battery. The hardest part was soldering the wires (my old bones and joints do not allow me to get in positions that used to be no problem). This post was great help to me, especially being electrically challenged. I have owned this truck since 1993 and don't want to give up on it. Thanks for all the replies.

That's good, I'm glad everything worked out for you!
I hear you on the old bones parts as well... I need to invest in, or build one of those over the engine creepers.

 

[Fastback67]

You don't live in Nevada. That is your "Governer".

I've done a lot of work to the truck since I got it. It has no trouble at all climbing up and down the mountains in NH these days, regardless of speed or load. The hard part is keeping it under 80 on the highway. I have to keep looking down, checking my speed to make sure it's not getting away on me.... LOL!

 

[Fastback67]

While attempting to recharge my A/C system last week and I discovered that I had a bad Expansion Valve, so I ordered a new one and installed it.
This morning I pulled down the system again for about an hour to dry everything out, then shut everything down, waited and checked for leaks. All looked good so I started recharging my A/C this morning using those little 12oz CA approved Child Proof Self Sealing Freon cans that take the special valve. I didn't have time to finish the job today before work, so tomorrow morning I'll have to pick up where I left off, but at least the system appears to be functioning normally now that I have replaced the faulty expansion valve.

I also mounted an auxiliary fuse panel and ground strap in an open area under the dash on the heater box. Easy to see the little Red indicators when mounted here. It's also much easier to get at when you want to add or remove something. I haven't powered it up yet though, I was to busy today... maybe tomorrow.

 

[ofelas]

Looking good Mike!

 

[Fastback67]

Thanks Chip!
I'll be mounting a few gages soon along with one or two other accessory items, and wanted a convenient place to power things up.

 

[ofelas]

Makes perfect sense. Reduce the load from those rare fusible links as much as possible

You ended up filling by weight or sight glass (assuming R12) ?

 

[Fastback67]

The original R12 system is still on the truck, but it has been converted to R134... A new system would charge quicker, but the old system is air tight and working fine, so I'll just keep charging until it's full... Charging by weight it takes 2.5 lbs of refrigerant according to the new label that was attached after the conversion.

 

[Fastback67]

Powered up my Aux Fuse Panel and Ground Bus this morning with a couple of 10 gauge cables.

I also added a Tin Plated Copper Aux Power Bus out under the hood next to the Battery, which is also fed by a 10 Gauge cable.

Added another 12oz of refrigerant to the A/C as well, but that's all I had time for this morning before work after doing the electrical. Still need to add another 16oz of refrigerant before I'm done.

 

[WalterJ]

If you want a little more go get a HX35 from a 2nd gen with a waste gated 12cm exhaust snail, its a direct bolt in replacement

Does that mean 1st gen has a MAP sensor, etc. to make use of the xtra O2?

 

[Fastback67]

I was having some issues with the steering on Montana recently. I didn't see anything obvious when performing the usual checks, but still, the steering was getting real funky, bad enough that I had to finally take it off the road.
I decided the best thing to do in this case was to simply tear it all down, right down to the king pins, so I did. In the process I discovered a number of deficiencies along the way that were definitely part of the problem, but the biggest one, the real culprit, turned out to be a half frozen steering knuckle on the drivers side. One side of the universal joint was fine, but the other side was froze up tight.
It's all taken apart now, but I did start the reassembly this morning. That said, the hardest part is done now anyway...
New King Pins and Lower Bearing Races installed on both sides.
A made a tool for installing the new bearing races, using one of the old ones. I ground the sides of the old bearing race down a bit on a bench grinder, then polished them with a bench mounted belt sander. I took off just enough so the old bearing race would freely slide in & out of the socket. Put the new races in the freezer for a bit, then tapped them into place. Worked like a charm. I also took a small needle gun to the yokes and removed 97% of the built up grime and scale that has accumulated over the last 30 years.

Tomorrow I should have the king pin assemblies all finished, buttoned up and ready to go.... and hopefully a little extra.

Frozen on one side

Old Pin and Bearing assemblies removed

New Pin's and Races installed

 

[Fastback67]

I only have 30 minutes to an hour to get everything done each day that requires my attention, so after paying bills this morning and running some errands out in town, I started back in on the truck. I only had about 30 minutes to play and I spent most of that time cleaning the dirt and grime off the old iron casting and machined surfaces. I did manage to get the lower king pin bearings and seals installed, then slipped the big yokes and tie rod into place. The only thing left to do here is install the BIG springs that hold pressure on the King Pins and put the covers on... torque it all down and add a few extra shots of grease.
Then it's time for the axles, bearings, rotors, hubs, calipers and brakes.