My first M998: Fixing her up

[1000eemonarch]

Starting this thread as kinda a log of my experience with my first M998... I'm thinking it would be fun to log the chain of events and lessons learned in the process, and would love to bounce ideas around on how to go about addressing things as they come up.

So, got this thing at auction October last year. Bit of an impulse decision, and I certainly did not do as much research as I should have. Oh well, might as well have fun learning the hard way .
The data plate showed 2008, altho the truck is much older, appears to have had a reset in '08. National guard truck.

Here's a photo from the auction site:



The EUC took forever to process. Over 4 months. But it finally happened, and here she is:




BTW this thing is a lot of fun!! So far rather happy with the entertainment value!

I'm still waiting for the SF-97 and still thinking on strategies for titling. I won't get into that here for obvious reasons, but if anyone has ideas don't hesitate to PM me

Thanks,
Alex.

 

[1000eemonarch]

So. Main concern at the moment is fuel tank, which came punctured.

Original tank is a part number 5582606-R, date code 01-86 (safe to assume that's the year of MFG of the truck)
The replacement I got is NSN 2910-01-447-3911




It appears to be interchangeable, however I'll need a different metal shield to attach to it... Any ideas on the part number for the shield, and anything else I need get to make the new tank fit nicely? Thinking I'll call Kascar (where I got the tank from) on Monday for advise....

Next question, what fuel level sender would you guys recommend? Tempted to get an NSN 6680-01-484-5367, which appears to be solid state (ultrasonic or capacitive?) rather than the mechanical flappy float deal...

 

[gtodan]

Go with the upgraded fuel level unit. You will have to eventually anyway. Their are TM's onsite here that will give you part numbers. That part of the forum shoul;d become your second home. BTW how you registering it in Commiefornia.

 

[1000eemonarch]

>> Go with the upgraded fuel level unit. You will have to eventually anyway.

Yep, thinking about that... NSN 6680-01-484-5367 is what I have in mind for the fuel level sender. Fortunately this truck has had the cutout in the floor for easy access after the fact:

https://www.logsa.army.mil/psmag/archives/PS2009/682/682-15.pdf

>> BTW how you registering it in Commiefornia.

I'm not sure yet..... Will learn the hard way. And yes, a lot of the longer term strategy for this truck will depend on how that goes.

 

[1000eemonarch]

Besides the fuel tank, here's a list of things that I'm currently thinking of:

Alternator is over-charging:
Appears to be a problem with the sense wire or regulator. Still researching this. Has the old style 60A unit

Tires. They are old and cracking. 2007 date code.
Having a debate between military surplus 16.5, new 16.5, or going 17" on Hutchinson H1 wheels. People are telling me to stick to the military theme and avoid H1 wheels. I personally hate the 16.5" size as finding new tires is no fun.
On surplus tires, seems like there's a bunch of people selling them in Michigan, and have heard good things about Alpha tread. Any ideas on best place to get them (and places to avoid?). Is it a good idea to run 10 year old tires, if they are like new and stored indoors?

Front driveshaft carrier bearing, rubber is old/cracked

LED Lights.
So far got a pair of Truck-lite 07370 NOS 7" headlight LED replacements. Seems like a good compromise between militaristic enough and modern enough... The Truck-lite 27270C was another consideration, but the 07370 were a pretty good deal, looks more militaristic and I'll give it a try.... Will take a long time to arrive but will post photos and report when they do.


Also thinking of going LED for all the other lights including dash lights. Any ideas on best ones to get?

Doors and a hard top are probably going to have to wait till much later in the process.... Especially considering I'm not sure on titling yet. But i'm certainly open to learning more about what's out there in that department....

Thanks,
Alex.

 

[Mogman]

Welcome to the family

 

[BLK HMMWV]

I'd focus on the paperwork before I spent another dollar on it.
What engine and trans is in it?
Do you have a park position on your shifter?
What emergency brake set up does it have?
You may have fun with that gas tank install depending on the existing e brake set up on your truck now.

 

[1000eemonarch]

>> I'd focus on the paperwork before I spent another dollar on it.

Totally agree on that. Yes, no point in throwing $7-15k of parts into a truck I won't be able to drive on the road. Fort now I'm keeping investment failry low and figure I can always sell it for what I have into it. Yes, a lot of wasted effort but it is good fun, and I'm enjoying it at the moment.

>> What engine and trans is in it?

6.2l nat. aspirated, 3-spd trans, 218 transfer case.

>> Do you have a park position on your shifter?

Nope

>> What emergency brake set up does it have?
>> You may have fun with that gas tank install depending on the existing e brake set up on your truck now.

Ebrake is on the brake calipers on the diff. Not on the driveshaft, so the fuel tank situation is not that bad.

And yes, you pointed out one the the big mistakes I made with this truck... Not buying a newer one with 6.5 turbo and 4spd trans. I still intend to have fun with this one, make the best of it, learn a lot, and maybe trade up to something different (M1165 looks nice) later.

Adding one more thing to my "to do" list... Glowplugs not working, wait to start light does not come on at all. Looks like the protective control box is a really common problem, and I have much reading to do in that regard. Will worry about figuring it out later, doesn't bother me now and looks like a pretty normal problem to have,

 

[3jacks]

Welcome to the addiction!

 

[Milcommoguy]

Late design fuel sender is a series of magnetic glass enclosed "reed switches" with a resistive network. Float goes up and down in a tube with a magnet attached. Simpleton design and works. Only problem is gauge moves in discrete steps, I think 8 maybe 7. No inbetween reads.

Analog or digital ?? they all work, CAMO

 

[1000eemonarch]

>> Late design fuel sender is a series of magnetic glass enclosed "reed switches" with a resistive network.
>> Float goes up and down in a tube with a magnet attached.

Ahha, makes sense! I was getting all fancy thinking ultrasonic or capacitive. Only question, why do none of the photos of this thing show the float?



And I do like this design better than the flappy float on a swing arm, think I'll get one along with whatever hardware I need to make the new tank fit.

 

[SCM35A2]

Nice project.

 

[osteo16]

>> Late design fuel sender is a series of magnetic glass enclosed "reed switches" with a resistive network.
>> Float goes up and down in a tube with a magnet attached.

Ahha, makes sense! I was getting all fancy thinking ultrasonic or capacitive. Only question, why do none of the photos of this thing show the float?

View attachment 793289

And I do like this design better than the flappy float on a swing arm, think I'll get one along with whatever hardware I need to make the new tank fit.

Id say the "float" is inside the tube.... Just my 2 cents.. Good luck with project.. I got mine in October and .......Its in a million pieces
but its fun, and it will eventually run like a scalded ape.. Best of luck.

Ocho

 

[TOBASH]

How do you know your tank has a hole in it?

My tank leaked, but it was the gasket to the top metal bracket that just needed a quick swap. I drive a similar rig, 1987 M1025A1 with 6.2 and three speed.

Now my rig no longer leaks fuel.

 

[Retiredwarhorses]

Swapping too a new A2 fuel tank allows for a nice refresh of critical component, such as fuel tank sock, sender, pickup tubes etc...plus, the tank is cheap. Also good to have in any sort of preparation for a 4L80e.
side note, unless the rear differential support brkt has been upgraded, you will need to cut or grind off the
old ebrake mount on the passenger side of the truck. Without a pic of what you have, no way to know if the new mount was installed during a reset or not.

 

[1000eemonarch]

>> Id say the "float" is inside the tube....

Possible... Then there should be a breather hole at the top of the aluminum tube... I'm guessing my curiosity will be satisfied soon enough when I get my hands on the modern fuel level sender.

>> I got mine in October and .......Its in a million pieces

Was tempted to go that route, but hard to justify at the moment.... Will just focus on addressing individual concerns one at a time, see where it goes...

>> but its fun, and it will eventually run like a scalded ape

This thing is a blast. We have already terrorized some parking lots and mounds of dirt. It's more fun than I expected.

>> How do you know your tank has a hole in it?
>> My tank leaked, but it was the gasket to the top metal bracket that just needed a quick swap.

This has a 3" gash at the bottom of the tank. Extreme offroading, forklift or intentional are my guesses. But yeah, I can totally see how it can leak from the top cover if all the nuts are not tight or the gasket is bad.

>> Swapping too a new A2 fuel tank allows for a nice refresh of critical component, such as fuel tank sock, sender, pickup tubes etc...
>> plus, the tank is cheap. Also good to have in any sort of preparation for a 4L80e.

Totally agree. Surprised they did not swap the tank along with all in-tank components when they did the reset in '08

>> unless the rear differential support brkt has been upgraded, you will need to cut or grind off the old ebrake mount on the passenger side of the truck

Good info! Here's whats under there now:





I guess I could attack it with a cutoff wheel and remove that mounting ear that's not being used... Maybe the cleaner/easier route is just buying an NSN 5340-01-301-792



Thanks for all the input!
Alex.

 

[TOBASH]

never mind. Retracted.

 

[Retiredwarhorses]

>> Id say the "float" is inside the tube....

Possible... Then there should be a breather hole at the top of the aluminum tube... I'm guessing my curiosity will be satisfied soon enough when I get my hands on the modern fuel level sender.

>> I got mine in October and .......Its in a million pieces

Was tempted to go that route, but hard to justify at the moment.... Will just focus on addressing individual concerns one at a time, see where it goes...

>> but its fun, and it will eventually run like a scalded ape

This thing is a blast. We have already terrorized some parking lots and mounds of dirt. It's more fun than I expected.

>> How do you know your tank has a hole in it?
>> My tank leaked, but it was the gasket to the top metal bracket that just needed a quick swap.

This has a 3" gash at the bottom of the tank. Extreme offroading, forklift or intentional are my guesses. But yeah, I can totally see how it can leak from the top cover if all the nuts are not tight or the gasket is bad.

>> Swapping too a new A2 fuel tank allows for a nice refresh of critical component, such as fuel tank sock, sender, pickup tubes etc...
>> plus, the tank is cheap. Also good to have in any sort of preparation for a 4L80e.

Totally agree. Surprised they did not swap the tank along with all components when they did the reset in '08

>> unless the rear differential support brkt has been upgraded, you will need to cut or grind off the old ebrake mount on the passenger side of the truck

Good info! Here's whats under there now:

View attachment 793324

View attachment 793323

I guess I could attack it with a cutoff wheel and remove that mounting ear that's not being used... Maybe the cleaner/easier route is just buying an NSN 5340-01-301-792

View attachment 793326

Thanks for all the input!
Alex.

just cut if off.....I do it all the time, takes about 2mins.
Thr tank vent is not on the pickup tubes, it’s on the top plate.
there is a large pickup tube with a sock on it, and the drainback tube.
the sock is expensive and only sourced through a distributor.

 

[TOBASH]

the sock is expensive and only sourced through a distributor.

RWH, any other materials suitable to make a sock?

I know you probably wouldn't do that RWH, but the AMG can't be the only manufacturer that used socks?

 

[Gamble]

South Dakota