Converting M998 to an M1026

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RockHillWill
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Re: Converting M998 to an M1026

Post by RockHillWill » Fri Jan 26, 2018 7:11 pm

For some reason, I had trouble adding these two pictures in the previous post. I downsized them from 800 pixels to 680 or so and it worked then.
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RockHillWill
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Re: Converting M998 to an M1026

Post by RockHillWill » Fri Feb 02, 2018 6:28 pm

Making some more small steps. Got the doors mounted and adjusted, heater hose at drivers side and the deep water snorkel added and added the missing plates around the radiator shell. The truck had two pieces of plywood on the floor that were 1/2" thick, and we wanted to add wood to the rear section as well. I had some 5/8" Baltic Birch plywood left over from a Bugatti fender build that was a 5ft square. I made a sketch and cut outs for the tie downs, etc and then added 1/8" of insulation to the front pieces to make them be the same height. Painted green to match. This required spacers to be placed between the plywood and the floor, so I epoxied some .100" washers to some Nylon 1/2" spaces and it required longer screws as I wanted to put the tie downs on top of the plywood. I was given a pair of 'better' Humvee seats, used but much better than what I currently have, and matched my 'as-found' approach for this build. I did not get the entire drivers seat, so I had to make an adaptor plate. It is mounted 2" below the two front mounts and 1-1/4" above the rear mounts. The adjusters worked great after a little bit of oil and persuasion. I made a mounting plate to be mounted at the center roof tie down bolt to hold the crew box for the rear passengers and will also hold the headphones and cables when not in use. There were already some holes in the two front mounting tubes for the roof and I made a cover plate that will hold an adjustable bracket to mount the 7" back up camera in a manner that makes it look like a rear view mirror. Around the perimeter of the roof, we have installed a series of 5/16" RivNuts to mount cable clamps as the current thinking is to route the highway cables along the edge of the roof rather than around the turret opening.
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RockHillWill
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Re: Converting M998 to an M1026

Post by RockHillWill » Mon Feb 05, 2018 7:43 am

Had good help from the wife this weekend and got a few more items off the check list. We got the battery disconnect switch installed and grommets for the cables, but don't have the additional cable at this time to complete the process. Replaced the windshield wiper blades with longer ones. The original part number is for an 11" blade, but I went to O'Riley's auto parts and found some 12" blades #61-12 and some 13" blades # 61-13. I bought the 13" long blades and cut 1/4" off the bottom and chamfered the rubber part 45 degrees. Works great so far. Reviewed the long offset of the pintle extension, the additional weight of the Rhino spare tire carrier and the fact that we intend to pull a loaded M1102 trailer and decided to use the 5/8" mounting bolts for the pintle extension. It required the milling of the last 3/16" of the bumper mounting hole 'sleeves' out to 5/8". Before learning of the previous response(s) information, I had the spacer plates made with the 5/8" holes. It went together without a hitch. Fabricated a pair of flag carrying brackets that will be sandwiched behind the antenna mounts and the body and installed RivNuts at that location as I had to buy a lot of them to get a good price and just want to use them wherever possible. Got the 5/8" Baltic Birch plywood painted and installed in the cargo area using longer bolts and a fabricated spacer to fit between the bottom of the plywood and the top of the floor so that the tie downs could used and loaded. Installed the pintle extension and the mud flaps. Waiting for delivery to install a 2" receiver hitch unit. Fabricated a small bracket for an array of cigarette lighter receivers. Rhino spare tire bracket is next on the list. The radio shelving and intercom 'stuff' is still being learned and will likely be a 'slow-go' installation.
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Last edited by RockHillWill on Tue Feb 06, 2018 6:12 pm, edited 4 times in total.

RockHillWill
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Re: Converting M998 to an M1026

Post by RockHillWill » Mon Feb 05, 2018 7:46 am

A few more pics.
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Last edited by RockHillWill on Mon Feb 05, 2018 6:55 pm, edited 1 time in total.

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Re: Converting M998 to an M1026

Post by dilvoy » Mon Feb 05, 2018 12:45 pm

Backer plates on the tire side of the rear fender panels are used with the antenna brackets so the fender panel is not damaged by the tall antennas swinging back and forth. Your flag brackets essentially do the same thing so you should not have to worry about anything there, but you might keep an eye on things.
George D. Paxinos

M998's
M1044
M1123A2


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Re: Converting M998 to an M1026

Post by RockHillWill » Mon Feb 05, 2018 1:51 pm

Thanks for the info George. I am not aware of the backing plates, perhaps I should locate a pair and use them in addition. What TM might I get the part number for them?

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Re: Converting M998 to an M1026

Post by JuanPrado » Mon Feb 05, 2018 2:44 pm

RockHillWill wrote:
Mon Feb 05, 2018 1:51 pm
Thanks for the info George. I am not aware of the backing plates, perhaps I should locate a pair and use them in addition. What TM might I get the part number for them?
Easiest for you would probably be duplicate the Flag holders plate with out the tube and cut back slightly to clear the inside of the fender wall. The OE look just like what you made.

Nice job on it all! Moving to New Orleans anytime soon? :)

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Re: Converting M998 to an M1026

Post by dilvoy » Mon Feb 05, 2018 4:02 pm

RockHillWill wrote:
Mon Feb 05, 2018 1:51 pm
Thanks for the info George. I am not aware of the backing plates, perhaps I should locate a pair and use them in addition. What TM might I get the part number for them?
I don't know the part number for this item. You might find it in a TM for a Radio Installation, but I don't think you will find it in a Humvee TM. With the tall fiber glass antennas, that rear fender can flex back and forth when the antenna is left loose in the vertical position. Your flag brackets will probably take care of any of that. You could also go to the later blast resistant antenna that looks like a non adjustable car antenna, but talller, but not as tall as the fiberglass antenna and is much lighter.
George D. Paxinos

M998's
M1044
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Re: Converting M998 to an M1026

Post by Ted Gates » Mon Feb 05, 2018 5:56 pm

The plates are available on eBay. The seller made them from my originals years ago.

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Re: Converting M998 to an M1026

Post by RockHillWill » Tue Feb 06, 2018 6:37 pm

Another step this morning. Wife and I added the spare tire carrier assembly, with 'hold-in-place' modification per JuanPablo. Welded in first plate to position it parallel to the airlift bumper, then using a .060" shim as a temporary spacer, welded in the second retaining plate. I also chamfered the inside edge of each plate to help the holder to slip in a bit easier without hanging up. Added the 2" receiver and tested out the spare tire bracket by loading the temporary spare tire. It went pretty well, but the spring holding the tensioner lever was not strong enough in either direction to be able to use only one hand. Also added both antenna mounts, flag supports and antenna bases, and will be adding a few other misc. items and the front winch before taking it to get the wheel alignments. Any need to differ from what the TM's show???
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Re: Converting M998 to an M1026

Post by dilvoy » Tue Feb 06, 2018 8:09 pm

I've never seen any DOT Approved Receiver Hitches attached to a plate like that. Make sure you keep an eye on it if you tow a trailer with it.
George D. Paxinos

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M1044
M1123A2

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Re: Converting M998 to an M1026

Post by RockHillWill » Wed Feb 07, 2018 5:11 am

Good morning George, thanks for the insight. I took a good look at that before I installed it. It seems that all are in approval of using (4) 1/2" bolts to mount that pintle extension where not only are those bolts expected to respond to the vertical shear loads, they are faced with a larger than normal tensile load on those two top bolts due to the leverage created by the length of the pintle extension. That 2" receiver tube is welded THRU the 1/2" thick plates with 3/8" thick gussets, and all four 1/2" bolts are subject to mainly vertical shear loads with very minimal tensile loads. The vertical 'shock' loading from the acceleration input from hitting a 'speed bump' far outweighs the linear tensile loads of pulling a trailer that has rotating wheels. I have pulled race cars and show cars around the country for over 45 years, and this hitch has no concern for me at this point. My current motorhome 'DOT approved' trailer hitch has no metal thicker than 1/4" and is attached with (4) 7/16" bolts. I pull a 32 foot extra tall enclosed trailer on 1800 mile trips on a regular basis. I will however, take your advice, and keep an eye on it when pulling my M1102 trailer or my standard flatbed car trailer. It is actually my intension to use that receiver hitch to move our non-military trailers around here on the farm.

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Re: Converting M998 to an M1026

Post by dilvoy » Wed Feb 07, 2018 12:07 pm

Just watch out for that drunk driver or texter coming up from behind. They can add a lot of shock to the hitch. Don't ask me how I know.
George D. Paxinos

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M1044
M1123A2

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Re: Converting M998 to an M1026

Post by RockHillWill » Mon Feb 12, 2018 7:09 am

A few more small items were accomplished in the last few days. Cut off the original front bumper braces that had to be replaced when the move was made to add bumper extensions and mount the winch. Rather than remove the original bolts, I took some good advice from here and notched the new brackets and only had to loosen and move the bolts. Added the inner cable support 'loop' and installed an original hook to the cable. Added a flashlight mount to the radio tray. Changed all four hard door latches with keyed ones from Minnesota company, and will also install their keyed ignition switch. Installed the rear FFCS, headsets and cables on the center bolt of the rear roof/hatch 'C' pillar. My friend showed me a new (to me) type of method to solder large cables. There is an 'insert' of solder that drops down in the connector, he heated it and slipped it in place.
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RockHillWill
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Re: Converting M998 to an M1026

Post by RockHillWill » Sat Feb 24, 2018 7:00 am

More small steps, but the setting the suspension changed my perspective about driving this truck. We set the caster, camber and toe in/out, changed to 24 bolt wheels, Baha tires at 40 & 35 PSI and this thing drive beautifully. I can now accelerate, cruise and brake without having to hold the steering wheel to maintain a straight line. Happy to let the wife take it for a cruise in this condition. More work to the radios and VIC 3 'stuff'. Got it installed, but will need to modify a few of the smaller brackets to maintain better vision out the right side rear view mirror, then finish running the cables to the rear VIC 3 FFCS's. Also mounted the 'arrowhead' support to the turret and gathering the bolts, pins, etc. to add on the .50 cal and cradle items. Am installing a backup camera and mounted the screen to look like a rear view mirror. Added a prototype upper mount for some switches to use on the 12v items. When installing the rear lift assists, I found one lower shock to be in poor condition and one that did not work at all. Replaced both of the lowers shock units and they both work quite well now.

Question: trying to work on the lower pair of bolts on the rear upper control arm brackets took some time and effort, as I was warned about. Is there a hand made 'special' wrench that might assist in this project?
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