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York OBA TJ Installation



Franks write-up on Stu's Website provided all the technical info I needed to complete this change. Some minor modifications were incorporated into his instructions since I didn't have a snorkel and didn't want to drill any holes. That meant a fabricated bracket would be necessary to make it look as stock as possible.



You can follow the above instructions for air box relocation and adjust accordingly or if you want to fab your own bracket then follow these instructions: 

The bracket was fabricated from 1" x 1/8" strap metal. This bracket will form a triangle to go from each of the three mounting holes on the bottom of the air box.  See diagram.



1.  Remove the air box and tube from the Jeep, then remove the air horn from the bottom half. You won't need this anymore.
2.  Remove the mounting fasteners from the bottom of the air box.
3.  Turn the bottom half over so that the mounting fastener holes are up.
4.  With a hacksaw and metal scriber, mark and cut a length of strap metal approximately 9 1/2" long. Just slightly longer than the two fasteners furthest from each other.
5.  With hammer and vise, bend the strap metal at each end to fit flat over the two holes and contour along the bottom of the bottom half.
6.  Mark with a center punch and drill the two end holes with a 5/16" drill bit.
7.  Attach this piece, that we will now refer to as piece "A", to the air box bottom as it would normally be attached to the fender using the stock bolts and nuts.  See Figure 1.



Figure 1

8.  With a hacksaw and metal scriber mark and cut another length of strap metal just slightly longer than required to go from the third bottom mounting hole to a position near one of the bolted holes of piece "A" this second piece will be referred to as piece "B".
9.  Mark and drill a hole at one end of piece "B" with a 1/4 width="25%" drill bit.
10.  With hammer and vise, bend the strap metal as required at each end to insure piece "B" sits flush on the third hole and slightly overlaps piece "A" near the selected hole of piece "A".
11.  Attach piece "B" to the third mounting hole and adjust piece "B" till an angle can be scribed where pieces "A" and "B" intersect.
12.  With a hacksaw, cut this angle on piece "B".
13.  Reinstall piece "B" on the air box bottom and adjust to proper position against piece "A" and tack weld pieces "A" and "B" at their intersection. See Figure 2.



Figure 2

14.  With a hacksaw and metal scriber, mark and cut a third piece of strap metal (a little longer than required) to complete the bracket triangle between pieces "A" and "B".  This is piece "C"
15.  With a hammer and vise, bend piece "C" as required at each end to follow the contour of the air box bottom to complete the triangle.
16.  With the metal scriber, scribe the required angles to cut to complete the triangle on piece "C".
17.  With a hacksaw, cut the angles scribed on piece "C".
18.  Tack weld piece "C" between pieces "A" and "B" to complete the triangle.
19.  Once all pieces are tack welded together, remove the bracket and finish welding all three pieces together.
20.  Angle grind and file to desired perfection.  See Figures 3 and 4.



Figure 3


Figure 4

Completing the bracket requires a brace that can utilize the passenger side motor mount to frame bolt.  Again, 1"x 1/8" strap metal is used to make this piece to weld to the bracket we just fabricated above.

1.   With a hacksaw and metal scriber, mark and cut a length of strap metal approximately 12 1/2" long.  This length is actual longer than required and will be cut to the proper length later.
2.   Drill a 7/16" hole approximately 1/2" from the end.
3.   Scribe another position approximately 1-1/2" from this same end.
4.   Bend the strap metal 90 degrees on this mark.  See Figure 5.


 Figure 5

5.   Half way up this piece, using an adjustable/crescent wrench and a vise, twist the strap metal approximately 120 degrees.  See Figure 6.



Figure 6

6.   Cut a length of 1/2" x 1/8" strap to approximately 9" long with a hacksaw.
7.   Using an adjustable/crescent wrench, twist this piece of strap metal approximately 90 degrees.  See Figure 7.


Figure 7

8.   With a hacksaw, cut a 1-1/2" x 1" x 1/8" triangular fillet brace.  See Figure 8.



Figure 8

9.   Trial fit the 1" x 12-1/2" piece by removing the passenger side motor mount to frame bolt and temporarily mount this piece into position.

A second set of hands would come in really handy, so call a friend.  My wife was available and was invaluable in these next few steps.

10.  Position the air box bottom bracket into approximate position, and with a medium point marker, mark the desired height and angle to be cut.  My long brace ended up being 9-3/4" long as measured from the 90 degree "L" bend to center of the angle just marked.  See Figure 9.



Figure 9

11.  Remove the long brace from the motor mount to frame bolt.
12.  With a hacksaw, cut the long brace at the previously marked angle.
13.  Tack weld the air box bottom bracket into position on the long brace with two tack welds.  See Figure 10.



Figure 10

14.  Temporarily install the entire bracket into position and temporarily install the air box.

Make any and all final necessary adjustments to the brace.  Insure hood clearance is checked by putting a drop light in the engine compartment, passing the cord to the floor underneath the vehicle and plugging the light in underneath the vehicle.  Turn on the light and slowly close the hood while watching for clearance between the hood and air box.  Once all adjustments are complete, it's time to strengthen and complete the bracket.

15.  Finish welding the brace to the air box bottom bracket.
16.  Tack weld the 9" x 1/2" x 1/8" strap metal to strengthen the brace as seen in Figure 11.



Figure 11

No fair laughing at the welds in these pictures.  This was my wife's first attempt at welding by herself (she tried so hard).  Actually they're not too bad for her first try.  Wouldn't you say?

17.  Weld the 1-1/2" x 1" x 1/8" triangular brace fillet next to the bolt hole to increase the strength of the 90 degree bend.  See Figure 12.



Figure 12

18.  Grind, file and thoroughly clean to desired perfection.  Rattle can spray paint the entire bracket and allow to dry.  See Figure 13.


Figure 13

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