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Monster Buggy is getting an upgrade,

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Why not make the np205  the drop box.

 What! And let everyone else have all the fun making chips?


D-mount will take up to much room in the machine,  His output shaft looks interesting, but $820 for just a rear output plus $100 core, He can keep building stuff for the high rolling truck pullers, I'll keep trying to make junk work.


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After some wreckless thought & no real planning, the decision was made to build my own case, after seeing what I had laying around, then ording some material, I only had to wait a few days to get started.

My material showed up last week, so Thursday after work I got busy cutting aluminum,

T-case 7-7-14 004.JPG

T-case 7-7-14 005.JPG

 Lots of preheating & welding to tie the .750" thick top, bottom & sides to the .5" front plate, I didn't get any pics since I was busy heating & welding,
After a little clean up it was time for machine work,
First the hole pattern was drilled to bolt back cover on.


Then flipped the box, lid down & started the bore for the input bearing with a hole saw.



The hole saw was run through both sides so the bores would be in line, finish work was done with a boring head in the mill,
Once complete I moved on to the intermediate shaft bore, with the smaller hole I could only bore one side of the box.


On the rear output the housing fits a 6.125 bore, but the register is only .150" deep, rather than bore a 6 inch+ hole & loose support for the intermediate shaft, I cut a 4" hole & stepped the register out, leaving more strength in the box.


The front output was bored through the other side, again to keep everything in line, clearance between the rear output housing & intermediate shaft/nut is pretty close, rather than grind for clearance I figured I'd use it for more support,

So after putting the housing in place, then drilling/tapping the mounting bolts, I dialed back in on the inter. shaft bore & fly cut a 2" pocket, a 2" OD washer will be used behind the inter. retaining nut, & should offer a little more support.


Here is the input/rear output after getting all the holes drilled/tapped for bearing/seal retainers.


Next up the whole unit was flipped over, I had to remover the cover, dial in on the inter. shaft bore, then reinstall the cover & bore the final hole,
More drilling & tapping for bearing retainers.


Test fit of the gears/shaft looked like it was going to work well.


The input gear is from a marrage box 205 & required a sleeve so I could use an output bearing to support the end of the input that would normally be in the pocket bearing,
Here is the sleeve installed,


When all the bores were done & bearing could be installed, i put everything in the case, first to make sure they would fit, but also to set up the the alignment of the gears, to get everything right, I had to pull the input shaft/bearing out of the case about .250" this was done with a spacer/washer I built, (but no pic) This put the input in line with the inter. shaft,
For the output I had to do a little work to the output shaft housing, first was taking .100" off the face that the bearing retainer/seal housing bolts to, then an aditional .050" off the face that bolts to the case, This lined the output gear up correctly with the inter. shaft, & also set the clearance between the two halfs of the output shaft.



With everything fitting in the case properly it was time to move on to the shift mechanism,
As mentioned before I'm using the stock 205 shift collar & fork, however a new shift rail would have to be built,
But first the case had to be bored for the rail,
To locate the shift rail bore I used the rear output housing, From the factory the rear housing has an ear that covers the shift rail bore,
I simply transfer punched through a stock 205 housing into that ear, then bored a .750" hole in the rear output housing,
With the housing bolted to the new case the hole could be bored in the correct location.

The shift rail will be sealed exit the case through the hole in the rear output housing, on the other side of the case I had to build something to support the shift shaft through its range of motion, & seal the hole in the case,

Basically I just set the cover on the mill, dialed into the shift rail bore, then drilled & tapped the bore to 1" fine thread, then build a boss that threaded into the bore,



Ok, I built the boss first, but who's paying attention anyway.
Either way the boss was threadad into the cover with a liberal amount of red locktite.



Once installed the boss was finish bored, then a hole had to be drilled & tapped in the case for the detent arrangement, while set up for that I decided to add a little bling, (edit) in this pic you can also see the 1/4" spacer behind the input bearing retainer.


The detent is a simple 1/2" bolt, cut to a measured lenth, then drilled/tapped for a 3/8 fine thread in the center, the spring & ball from a 205 is used along with a set screw & jam nut to set tension on the detent spring.
Here is the test bolt, (I replaced this yesterday with a stainless bolt, drilled/tapped the same way.


I was dissapointed to learn that the .750 end mill, cut my shift rail bores .005 over sized, & the material I had set aside for the project was .010 under,
so a fair amount of time was spent building a shift rail out of 1" stainless stock, getting it to size was easy enough, the challeng was getting a finish I felt would work with the seal. Then the shift fork had to be machined to work with the new shaft, kind of a snow ball effect, but I feel the finished part was worth the effort.
After some careful measuring the shaft was set up in the mill for detents, roll pin holes, & got provisions for linkage attachments.


In this pic you can also see an extra hole near the end of the shaft, this is a oil hole that feeds a galley drilled in from the end of the shaft, it does not so much lubricate the boss that is threaded into the cover, (since it's submerged in oil) but lets the oil out of the boss as the shift rail slides in,



Final assembly with the shift fork installed,



Here is the shift rail in place, the extra roll pin is to keep the rail/fork from going to far (out of gear) you can also see how the detent bolt/assembly works.



For sealing the shift rail the case was bored for a lip seal, the seal is behind the ear on the rear output housing, I did not get a good pic, but it can be seen behind the shift rail assembly in this pic.
T-case 7-7-14 006.JPG


With all the machine work done, the whole case got a good scrubbing, then began final assembly, as you can see in the pic above the shift rail seal was installed, then all the bearings in the rear output housing, finally the input bearing/retainer, & output housing were installed.

T-case 7-7-14 007.JPG


Next the rear output was dropped in.
T-case 7-7-14 008.JPG


Shift rail, fork, & collar were next.

T-case 7-7-14 010.JPG


Front output set in place,

T-case 7-7-14 011.JPG


The intermediate gear slids in next.

T-case 7-7-14 012.JPG


Finally the input shaft,
T-case 7-7-14 013.JPG

Earlier I posted about using a washer with a 2" OD that would rest against the saddle machined into the rear output housing, this is what that looks like after assembly,



After everything was assembled I slid a couple 205 yokes on the outputs to see what the scales had to say.


The assembled unit minus yoke/flanges,









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This case is one rang only, no hi-low, but will have the capabilty do disconnect the rear axle for front dig,

The combination in the box makes 1.4:1,


For the range box in front of this unit I chose to go with a Behemoth strong box DIY kit, using NV271 gears,

I called Jacob, told him what I was doing, & what my time frame was like, fortunately he had the kit I needed sitting on the shelf, minus the strong box to Ford 205 output shaft, & shift lever. So he shipped out a kit, & cut an output to ship off with his next batch going to hardening,

The strong box seems like a pretty good price, plus I already had a 271 laying around I could steal the planetary arrangement out of.

Here is what the strong box looks like when it showes up.



The quality is pretty good, & includes all the needed hardware.

Only pics I have so far of assembly is a few of pressing the 271 ring gear into place,


T-case 7-7-14 002.JPG


T-case 7-7-14 003.JPG

My Strong box output shaft & shift lever should be here by next days off so I can continue getting the new t-case installed.




When complete, I will have a high range of 1.4:1, & a low range at just under 3.8:1




    Rock AWN!

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This is insane .. this is ridiculous ... my jaw is on the floor.


Incredible work, fab, thought, engineering ... wow!


Leroy, what do you do for work out of curiousity? You may be under-employed!



Once along time ago, in a subduction zone not to far away, great thrust faults and up-lift occurred, that my friend blows me away..... In this great land, we all treasure the same, I see no reason to only have mud trails, thats just lame. Thus today I made a vow I promise to uphold, I will find a rock trail in Alberta by hunting through the heat, rain and even the cold. So to all those Igneous and sedimentary rocks around, look out, the day is coming when you will be found.

Rock Poss'e 06


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Leroy, what do you do for work out of curiousity? You may be under-employed!




I'm a small vehicles mechanic at a gold mine,

it's not a real gratifying job anymore, but I work as hard as I want to, make $35ish per hour, & only work half the year,

the other half I do crap like this.


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WOW!!! I can't wait to see it.


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That is some gnarly fab right there!!!! I only wish I had half that skill.


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I second that, amazing work!!

- "FLIP"....  Seems I consistently prove my nickname is appropriate.

Soup Man

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How big is the new drop t case?


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How big is the new drop t case?

The drop box by itself is comparable in size to an NP205,  with approximately 9" of drop, (center to center of input & output shafts)



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Leroy that's amazing!  Good job man. Wow!


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 With Hard Grass Havoc coming up the first of August the push is on to get the buggy ready, with plenty to do & time running out I did not spend much time taking pics,
This days off started with lots of disassembly.



Since the T-case had to come out, & I have a new torque converter to put in, I figured I'd rebuild the transmission while it was out, turned out to be a waist of time, since it looked pretty much brand new inside, but it's done now, & as long as I put everything back together right, should last several years again.

Disassembly & trans rebuild did not take long, the time killer was reassembly, but only because I had a list of changes I wanted to make,
After installing the new converter, hooking the engine & trans back together, then sliding it back in the chassis, I decided now was the time to relocate the engine oil filter, in the original location there was only about 1/2-3/4 of an inch between the filter & the header collector, tho it never seemed to really hurt anything, I'm pretty sure it was just soaking the oil with more heat, & if theres one thing this does not need, it's more engine heat.

After mixing some parts from a filter relocation kit I got from Chestonscout, & a filter housing I had at the shop, I got the filter moved to a mount on the trans bell housing, not only away from the heat, but also much easier to change the filter at oil change time.
No filter in place in this pic, but you get the idea.


Another change was adding steering coolers, up til now I have not been running one, but with upping the volume, I figure it's time to look into it, I had an 18" Derale inline trans cooler similar to what PSC claims as their #1 seller, but fitting an 18" long cooler any where was a no go, so I cut it in half & made two 9" long coolers,


Still, finding a place was challenging, I settled on putting it over the drivers valve cover, since this location was right in line with the pump, a couple simple brackets, then hoses, & that was done.


I question the effectivness of the cooler being mounted on the engine, but I have seen far worse, & has to be better than no cooler at all.

To button up the front steering I installed a new PSC pump, that is supposed to be higher volume,
So far I am not that impressed, just pulling it out of the box & looking it over I see nothing that makes this pump anything special, or gives any advantages for my needs,
It looks like a $35 Napa pump with a few simple mods to the fitting,
However I will wait til I can actually test the pump to give a full opinion,
 I hope I can come back & report there is some form of voodoo that makes the thing work 10 times better than a modded parts store P-pump,


While the engine & trans were out I made the required modifications to a couple tubes in the belly area to make room for the new case,
Later in the week I got the rest of the parts to finish assembly of the Behemoth Strong box, I got a couple pics of the parts, but must be on the other camera,
After it was assembled I made sure everything mated up to the new case correctly,


Once I knew that everything should fit the strong box & case were installed, & filled with oil,

Here is everything in place, (you can also see the trans cooler that was relocated into the trans tunnel, which required more mounting & plumbing changes)


Thats pretty much all I got done,
I'm down to reinstalling the radiator/coolant, seats, & shifter, then building new t-case shift linkage & drivelines,
Probably get it buttoned up just in time to load it on the truck, head for Canada, & hope for the best.



    REcTal Itch???????

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Its funny u say that about the psc pump... we had one on the hog and all it did wS leak out the shitty weld on fitting....

We deal with krc cor our pumps they are well built units..
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