HMMWV oil cooler screws

[Mogman]

Just want to confirm before driving 100 miles round trip to the specialty tool store that the allen head screws for the oil/trans/steering cooler is 3/16.

 

[Guyfang]

Got a NSN or part #?

 

[Mogman]

I looked up the bolts and they are SUPPOSED to be 5/16-18 (MS16995-72) witch would make one ASSUME they were USS but nothing fractional fits 3/16 too small 7/32 too large, 5MM about right but anyone that puts such a small drive on a 5/16 bolt is a total moron, I am just going to drill the dang things out as I am replacing the radiator anyway, but now I will have to wait on bolts cuz cap head screws are hard to find around here and these are really stuck..

 

[Mogman]

OH, maybe I should look in my HMMWV special tool box.....

 

[Guyfang]

This help any?

	THREAD CLASS	3A
	THREAD DIRECTION	RIGHT-HAND
	THREAD LENGTH	1 1/8 INCHES MAXIMUM
	FASTENER Length	2 1/2 INCHES MAXIMUM
	HEAD STYLE	FLAT CHAMFER
	HEAD DIAMETER	0 457/1000 INCHES MINIMUM AND 469/1000 INCHES MAXIMUM
	HEAD HEIGHT	0 153/500 INCHES MINIMUM AND 313/1000 INCHES MAXIMUM
	INTERNAL DRIVE STYLE	HEXAGON
	NOMINAL THREAD DIAMETER	0 39/125 INCHES
	WIDTH ACROSS FLATS	0 1/4 INCHES MINIMUM AND 253/1000 INCHES MAXIMUM
	THREAD QUANTITY PER INCH	18
	MINIMUM TENSILE STRENGTH	80000 POUNDS PER SQUARE INCH
	HARDNESS RATING	80 ROCKWELL B MINIMUM OVERALL
	MINIMUM YIELD STRENGTH	30000 POUNDS PER SQUARE INCH
	MATERIAL	STEEL COMP 304 OVERALL
	MATERIAL DOCUMENT AND CLASSIFICATION	QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OVERALL
	SURFACE TREATMENT	PASSIVATE OVERALL
	TEST DATA DOCUMENT	81348-FFS86 SPECIFICATION (INCLUDES ENGINEERING TYPE BULLETINS, BROCHURES,ETC., THAT REFLECT SPECIFICATION TYPE DATA IN SPECIFICATION FORMAT; EXCLUDES COMMERCIAL CATALOGS, INDUSTRY DIRECTORIES, AND SIMILAR TRADE PUBLICATIONS, REFLECTING GENERAL TYPE DATA ON CERTAIN ENVIRONMENTAL AND PERFORMANCE REQUIREMENTS AND TEST CONDITIONS THAT ARE SHOWN AS "TYPICAL", "AVERAGE", "NOMINAL", ETC.). OR 96906-MS16995-72 STANDARD (INCLUDES INDUSTRY OR ASSOCIATION STANDARDS, INDIVIDUAL MANUFACTUREER STANDARDS, ETC.).
	THREAD SERIES DESIGNATOR	UNC
	NONDEFINITIVE SPEC/STD DATA	6 TYPE

 

[Mogman]

Not really, I found all that info it says nothing about the drive size, the fact is the drive head is too small and shallow for a 5/16-18 fastener, never had them this bad stuck before ether, and they are pretty soft so the heads strip out easy, should be easy to drill though, GRR

 

[NDT]

Order your fasteners from McMaster Carr and they magically appear in 3 days. Save gas.

 

[Mogman]

Already have the screws ordered, thanks.

 

[Mogman]

Well as it turned out the side I started out had already been boogered up by a previous genius so I ended up drilling them, the other side was different they came out but they were pretty darn corroded, the entire stack is a disappointment, looks like AMG farmed that out to a third grade class somewhere.

 

[Mogman]

Order your fasteners from McMaster Carr and they magically appear in 3 days. Save gas.

I bet they would appear fast, just looked them up and the 4 screws are nearly $50 plus shipping

 

[Retiredwarhorses]

The socket cap bolts for the oil cooler are 5/16…you don’t need the button heads you see on some, you can use a standard 5/16 socket head “Hex” socket from any hardware store.