Fixing the 1998 HMMWV

[mrandig]

Right splash shield removal.

Now to remove the right splash shield. This time, we've got the correct picture. In general, this is almost the same process as the left side, just with fewer parts.



Remove the bolt, washers and nut at the lower front of the splash shield. These were 14mm for me.


Remove the nuts from the studs at the control arm. There will be one upper and one lower, securing the shield to the airlift bracket. For me, these were also 14mm.


There will be a bolt aft of the control arm. Beyond indexing the shield into position, this doesn't seem to do anything. Somebody here might know more about this than me.






The final bolt will be at the rear, towards the very bottom. Rather than securing the shield to the frame, this secures the fuel line to the body. For me this was 13mm.




Give the shield a few wiggles and it should come out. Be gentle.


Lastly, I like to give everything a good rinse off after removal. Wife's dishwashing brush works well.

 

[mrandig]

Power steering cooler removal.

I decided after dinner tonight that I would start removing the cooling stack. This would be the power steering cooler, engine/transmission oil cooler, and finally, the radiator.

Starting with the power steering cooler.


The power steering cooler has 2 hex bolts, one on each side (left and right). These require a 3/16 hex key (Allen wrench) to remove.


The right side came out fine. I was getting worried I'd needed to change to a hex bit socket, but the Allen wrench ended up working ok. I also loosened the upper bolts for the engine/transmission oil cooler (not shown), as they're the same size and will be coming once the power steering is out.


When I got to left side, the bolt stripped. One twist and it was done for. This is supposed to be military-grade hardware?

Just. Like. That. I think we're done for the evening.


Surprisingly, this is the first bolt on this truck that's stripped on me. Unfortunately, sitting low and behind the power steering connections, it's in a horrible spot.

At the moment, I'm really annoyed, and now I need to come up with a game plan here on how to get this bolt out. I'm actually almost speechless.

 

[mrandig]

Tail gate chain replacement.

Here's an easy one. These are replacement chains for the tailgate. They help keep the tailgate closed, and when it's open, they help keep the tailgate level.

This kit, when installed, sits a little weird but otherwise seems OK. The original body connection uses a formed link; the new ones use a shackle.

Original pic.


Right side installed.

Left side installed.


Job completed.

 

[mrandig]

Just wanted to follow up on an earlier post to this thread. Way back when, in post #6, I had questions regarding the driver's side mirror assembly.

This mirror has a low mounting point, rather than mounting at an equal height to the passenger side. The latter (equal height) configuration seems to be more common, and this truck does have those riv-nuts installed also (damaged however). My eyeballs aren't calibrated, but it looks like it sits about 6" lower.






I've researched this to the point that I don't even remember where I looked or what I've come up with as a result.

The -24P gives me 5 different listings for mirrors; none are specific to an M1123 A2 (UOC NNN). The -24P does say however, that the mirror currently installed is the correct part number for a "lower mount" mirror.


Neither the -20 nor -24P are particularly clear on how this is supposed to look once installed. The -10 however, does have this...



So, back to my original question - does this mirror look like it's installed correctly?

Thanks in advance.

 

[mrandig]

Let's try getting this hex head out.

A few episodes back, we had stripped the bolt attaching the power steering cooler to the transmission/oil cooler. This has concerned me a bit, as it's a bad location and I have to be careful how I do this (I'm clumsy by nature). One slip and I could very easily damage something I'd regret.


First up, left-handed drill bits.

NOPE


Next, we'll try some screw extractors. I did not realize that these were "as seen on TV". I feel much better now about my prospects. Maybe I can be in one of their TV commercials.

NOPE


For our third try, I'm just going to stop being careful and smack the crap out of it. Even though this is a hex, it's a stripped hex; I'm going to take a T-30 socket, then hit it with a hammer until it fits. Once it's stuck really good, then maybe I can turn it out with a socket.

YES!!!





Success. I win again.

I don't want to take this all the way off just yet, as then it will be a hassle to get the hoses off. At least it's loose now.

Sometimes the simple solution really is the best solution. And a hammer.

 

[Mogman]

Let's try getting this hex head out.

A few episodes back, we had stripped the bolt attaching the power steering cooler to the transmission/oil cooler. This has concerned me a bit, as it's a bad location and I have to be careful how I do this (I'm clumsy by nature). One slip and I could very easily damage something I'd regret.
View attachment 944366

First up, left-handed drill bits.

NOPE
View attachment 944365

Next, we'll try some screw extractors. I did not realize that these were "as seen on TV". I feel much better now about my prospects. Maybe I can be in one of their TV commercials.

NOPE
View attachment 944367

For our third try, I'm just going to stop being careful and smack the crap out of it. Even though this is a hex, it's a stripped hex; I'm going to take a T-30 socket, then hit it with a hammer until it fits. Once it's stuck really good, then maybe I can turn it out with a socket.

YES!!!
View attachment 944369

View attachment 944370

View attachment 944371
Success. I win again.

I don't want to take this all the way off just yet, as then it will be a hassle to get the hoses off. At least it's loose now.

Sometimes the simple solution really is the best solution. And a hammer.

I have had that happen several times, I find it easier to just drill out the head and when the trans/engine cooler is off there is plenty of threads left, add some heat and they come right out.

 

[REF]

Allen wrenches are cheap, when one starts to strip I push the wrench in as deep as I can and tack weld the wrench to the head of the bolt, the heat of the weld tends to free up the threads. When it comes out cut the bolt off and your wrench is just a little shorter.

 

[mrandig]

Gauge replacement.

Back at the start of this project, one of first things we found was that the gauges didn't work. While they did light up, they were otherwise dead and filled with moisture.

Even if they did work, it wouldn't matter, as they can't be read. They will need to be replaced.


After cracking open the dash panel to take a look, it's no wonder there's issues.


Making sure to mark everything before taking things apart. Removing the top connections first makes it easier to get access to the bottom ones, and vice-versa.


A little quick dry electric cleaner. By a little, I mean an entire can (almost).


Some fine steel wool to clean up any contacts, especially the grounds.


This ground is now clean and very shiny. The picture doesn't really show how much better this is now.


And finally, some dielectric grease on all of the connections.


Once we've got the lower gauges in, we'll do a function test. We'll save the upper gauges until we can confirm these are working.

The batteries have been on a trickle charger for the last three months, so they should be ready to go.


Success! Lower gauges and speedometer installed.

At least the voltage meter works, so we know we have both power and ground. The fuel gauge isn't moving, so either we're out of fuel, or there's something wired incorrectly. The connections should be plain-to-plain, stripe-to-stripe, and ground to strap.


I'll be back in a while, once all of this work is finished.

 

[Mogman]

Gauge replacement.

Back at the start of this project, one of first things we found was that the gauges didn't work. While they did light up, they were otherwise dead and filled with moisture.

Even if they did work, it wouldn't matter, as they can't be read. They will need to be replaced.
View attachment 944531

After cracking open the dash panel to take a look, it's no wonder there's issues.
View attachment 944523

Making sure to mark everything before taking things apart. Removing the top connections first makes it easier to get access to the bottom ones, and vice-versa.
View attachment 944524

A little quick dry electric cleaner. By a little, I mean an entire can (almost).
View attachment 944525

Some fine steel wool to clean up any contacts, especially the grounds.
View attachment 944526

This ground is now clean and very shiny. The picture doesn't really show how much better this is now.
View attachment 944527

And finally, some dielectric grease on all of the connections.
View attachment 944528

Once we've got the lower gauges in, we'll do a function test. We'll save the upper gauges until we can confirm these are working.

The batteries have been on a trickle charger for the last three months, so they should be ready to go.
View attachment 944529

Success! Lower gauges and speedometer installed.

At least the voltage meter works, so we know we have both power and ground. The fuel gauge isn't moving, so either we're out of fuel, or there's something wired incorrectly. The connections should be plain-to-plain, stripe-to-stripe, and ground to strap.
View attachment 944530

I'll be back in a while, once all of this work is finished.

You really do not need to tag the wires, they all have ID tags and there is no guarantee they were connected correctly to begin with, that is what schematics are for.

 

[mrandig]

You really do not need to tag the wires, they all have ID tags and there is no guarantee they were connected correctly to begin with, that is what schematics are for.

Agreed. It's not necessary to tag each wire. I check the numbers on each wire, then I organize them by the gauge they go to. That's where the tape comes in. Wires 27G, 33A, and 58E for temperature; wires 27J, 58H, 28A for fuel; etc., etc.

It's easier for me.

 

[mrandig]

So, this weekend has not been terribly productive. A few things got done, but most of this time was spent fiddling with electrical issues.


Brake warning switch and light.

A few posts back, we had replaced the entire parking brake assembly. Now it's time to figure out why the brake warning light isn't working.

Removed, cleaned, tested and reinstalled the brake warning switch. This is a pressure switch, so when the handle is down, the circuit is broken, when it's pulled up, the circuit is complete. We have continuity, so no problems on the bottom end.


Looks like we may need another new part. Now I get to take out the air restriction gauge I just installed.



Turn signal cancelling switch.

A few episodes back we also found that the turn signal wouldn't cancel out. The culprit ended up being the turn signal cancelling ring.


This ring has two posts, which are used "cancel" the turn signal, in a given direction, as the steering wheel passes over a small lever on the turn signal switch. As it happens, both posts had been sheared off at some point, way back when.

Probably just failed due to age and wear.


The ring has three screws; once removed, the ring can be pulled off. As it's basically a clip, it will make a small snap. No removal of the steering wheel is required.


Installation of the new ring is simply the reverse of the removal.


There will be two posts that need to be removed after installation and adjustment. If you don't, the steering wheel will only turn as far as the posts will allow, and then bad things will happen. I just used a pair of wire snips, leaving about 1/4" remaining.


Once everything is complete, it's time to function test. We're all good here, so I guess we can at least show one thing done for this weekend.

 

[mrandig]

The thing that took most of my time this weekend were the gauges.

Back in few posts ago (#88 ), I had mentioned that the fuel gauge wasn't behaving correctly.


Everything else installed just fine and also tested correctly.


In general, I can't say that I'm impressed with the gauges. While they carry the correct NSN and part number, I can't get over the feeling that these are some sort of knockoffs. They're not Faria's, and aside from the speedometer, I don't think they're Clark's. Maybe someone can help identify these. I don't think I'd recommend.

Note the faces look odd, particularly the oversized fonts that are also a bit crooked.


No manufacturer identified.


The rear of these gauges are different also. They are not compatible with the original brackets that came with the truck. Also, there are no striped plugs, only two plain ones.


And then there's the brackets. The ****** brackets.

Left to right is the original factory bracket, a new "vertical" bracket with short legs, and a new "horizontal" mounting bracket with a figure 8 in the center, which would need to be modified, as the legs would be too long to be useable.


As I would come to find out, the vertical mounting brackets are fine for the top row, but the horizontal brackets must be used on the lowers, or the dash won't go back together correctly.


So, going beyond my thoughts on the gauges, the fuel gauge is just not happening.

We've got good power (24J), and we've got good ground (58H), but then we've got nothing?

It's hard to see in this picture, but shining a light through the tank, it looks like it is mostly full.


The sending wire (28A) tells me differently. Apparently, I should be almost empty.


Regardless of what the sending unit is telling me, the gauge tells me nothing. When the ignition is turned on, I just get a quick snap up to full and then right back to 0.

With the sending unit disconnected, the gauge should go full scale to the full side, but it doesn't. With the 28A port on the gauge grounded, the gauge goes half-way, and that's not right...

This makes me wonder if I have both a new gauge that's bad out-of-the-box, as well as an existing sending unit that's not working properly. The old gauge never worked, so it's not like I can use that one to cross-check.

I know what I will be spending my time on for the rest of today.

 

[mrandig]

Windshield washer reservoir and pump.

I may call it for today after this.

When I first checked this truck out, the wipers worked but the washer pump was dead. I guess now is as good of a time as any to get this fixed.

Here's the existing pump. It doesn't look bad, but it's definitely crusty inside. The reason the fluid is blue in the picture is because of me. I tried to get away using some fluid from NAPA, and now it's leaked everywhere and turned everything blue.

There are three bolts holding this assembly in place. Two bolts are 7/16" and go through the reservoir body. One is 5/16" and goes through a tab attached to the pump. The rear fasteners do bolt through into the cabin, but I didn't have any problems doing this without help.


There's two electrical connections under the dash. These run though a grommet from the cabin to the pump.




Disconnect the washer hose from the pump.


Old reservoir and pump removed from truck.


Reinstallation is the reverse of removal.






Here's the new reservoir and pump installed. Looks pretty good.


Looking at the old tank, it's not really surprising the old pump failed. It definitely got some corrosion.


Time to give everything a test and make sure it's put together correctly.


And nothing. Nothing happened. Even the wipers, which used to work, don't work anymore.

We have more gremlins.

 

[Mogman]

So, this weekend has not been terribly productive. A few things got done, but most of this time was spent fiddling with electrical issues.


Brake warning switch and light.

A few posts back, we had replaced the entire parking brake assembly. Now it's time to figure out why the brake warning light isn't working.

Removed, cleaned, tested and reinstalled the brake warning switch. This is a pressure switch, so when the handle is down, the circuit is broken, when it's pulled up, the circuit is complete. We have continuity, so no problems on the bottom end.
View attachment 944742

Looks like we may need another new part. Now I get to take out the air restriction gauge I just installed.
View attachment 944743


Turn signal cancelling switch.

A few episodes back we also found that the turn signal wouldn't cancel out. The culprit ended up being the turn signal cancelling ring.
View attachment 944744

This ring has two posts, which are used "cancel" the turn signal, in a given direction, as the steering wheel passes over a small lever on the turn signal switch. As it happens, both posts had been sheared off at some point, way back when.

Probably just failed due to age and wear.
View attachment 944745

The ring has three screws; once removed, the ring can be pulled off. As it's basically a clip, it will make a small snap. No removal of the steering wheel is required.
View attachment 944746

Installation of the new ring is simply the reverse of the removal.
View attachment 944747

There will be two posts that need to be removed after installation and adjustment. If you don't, the steering wheel will only turn as far as the posts will allow, and then bad things will happen. I just used a pair of wire snips, leaving about 1/4" remaining.
View attachment 944748

Once everything is complete, it's time to function test. We're all good here, so I guess we can at least show one thing done for this weekend.

On the brake switch, pull the wire from the brake equalizer and ground it to see if the light comes on.

 

[mrandig]

This has been a frustrating week. Fortunately, the stripped bolt at the power steering cooler came out, but now I'm left with electrical gremlins to chase with the fuel gauge and sender, the wipers and washer pump, and the brake indicator. I'm sure there's more I'm forgetting...

At some point, I still need to get around to the work that was actually planned - replacing the water pump, power steering pump, and hydro boost unit.

Anybody hungry?

 

[Coug]

common issue for wipers and washer fluid is the electrical connections under the windshield. If you aren't planning on folding the windshield then removing the spring loaded contacts and connecting the wires in the frame to the ones in the windshield solve that issue.
Other issue can be bad connection at the wiper motor controls.

 

[mrandig]

On the brake switch, pull the wire from the brake equalizer and ground it to see if the light comes on.

Thanks Mogman.

No joy. Grounding the wire at the proportioning valve didn't work either.

 

[mrandig]

common issue for wipers and washer fluid is the electrical connections under the windshield. If you aren't planning on folding the windshield then removing the spring loaded contacts and connecting the wires in the frame to the ones in the windshield solve that issue.
Other issue can be bad connection at the wiper motor controls.

I can't see it being anything else. There's no power at the wiper motor.

Glad I just got around to putting the top on. Now I get to take everything off.

 

[Mogman]

Thanks Mogman.

No joy. Grounding the wire at the proportioning valve didn't work either.

Then it is likely ether the lamp is not getting power from the inst. panel of the lamp is bad.

 

[Milcommoguy]

The thing that took most of my time this weekend were the gauges.

Back in few posts ago (#88 ), I had mentioned that the fuel gauge wasn't behaving correctly.
View attachment 944749

Everything else installed just fine and also tested correctly.
View attachment 944750

In general, I can't say that I'm impressed with the gauges. While they carry the correct NSN and part number, I can't get over the feeling that these are some sort of knockoffs. They're not Faria's, and aside from the speedometer, I don't think they're Clark's. Maybe someone can help identify these. I don't think I'd recommend.

Note the faces look odd, particularly the oversized fonts that are also a bit crooked.
View attachment 944751

No manufacturer identified.
View attachment 944755

The rear of these gauges are different also. They are not compatible with the original brackets that came with the truck. Also, there are no striped plugs, only two plain ones.
View attachment 944752

And then there's the brackets. The ****** brackets.

Left to right is the original factory bracket, a new "vertical" bracket with short legs, and a new "horizontal" mounting bracket with a figure 8 in the center, which would need to be modified, as the legs would be too long to be useable.
View attachment 944753

As I would come to find out, the vertical mounting brackets are fine for the top row, but the horizontal brackets must be used on the lowers, or the dash won't go back together correctly.


So, going beyond my thoughts on the gauges, the fuel gauge is just not happening.

We've got good power (24J), and we've got good ground (58H), but then we've got nothing?

It's hard to see in this picture, but shining a light through the tank, it looks like it is mostly full.
View attachment 944756

The sending wire (28A) tells me differently. Apparently, I should be almost empty.
View attachment 944754

Regardless of what the sending unit is telling me, the gauge tells me nothing. When the ignition is turned on, I just get a quick snap up to full and then right back to 0.

With the sending unit disconnected, the gauge should go full scale to the full side, but it doesn't. With the 28A port on the gauge grounded, the gauge goes half-way, and that's not right...

This makes me wonder if I have both a new gauge that's bad out-of-the-box, as well as an existing sending unit that's not working properly. The old gauge never worked, so it's not like I can use that one to cross-check.

I know what I will be spending my time on for the rest of today.

Did you have to pay the 145% tariff for no name Chinese parts ?

Taxes are due today, CAMO