1988 Bronco II

[Randall008]

Hey, new to forum. I’ve got a 1988 Ford bronco ii with a 2.9 v6 The bolts that hold down my motor mounts/motor mount insulators are loose. What should I torque those down to? I have the hanes manual and for some reason it gives very specific torque specs for fords 4 cylinder engines, but does not give any for the V6.
Any help would be appreciated. Thank you in advance

 

[franklin2]

Don't worry about any torque values. Get them as tight as you can with a regular wrench or 3/8 ratchet. That will be good enough.

 

[gaz]

85 foot pounds

 

[franklin2]

85 foot pounds

You will probably need a 1/2 drive ratchet and socket to get to that value.

 

[Randall008]

Thank you for all the responses. This helps a lot. I could not find the answer or even the question anywhere. I have a 1/2 so I should be good

 

[Curious Hound]

Quite often, when in doubt, use the standard torque spec for the fastener according to it's size, material and grade. These specs are easy to find on Google. Bear in mind the type of material the fastener is threading into. Softer metals may have lower torque specs.

So, for a 9/16" grade 5 coarse thread bolt in steel, the torque would be 82-91 ft-lbs.

U.S. Bolts - Tightening Torques

Recommended bolt torques.

www.engineeringtoolbox.com

Also, remember bolt size is a measure of the thread diameter, NOT the size of the wrench you use on it.

 

[sgtsandman]

Actually, it's the shank diameter and the number of threads. So, 1/4-28, as and example, is a 1/4" shank with 28 threads per inch. The threads are not always the same outer diameter of the shank size. So, it's better the go by shank OD than thread OD.

 

[Curious Hound]

Actually, it's the shank diameter and the number of threads. So, 1/4-28, as and example, is a 1/4" shank with 28 threads per inch. The threads are not always the same outer diameter of the shank size. So, it's better the go by shank OD than thread OD.

True. But it is generally noted as "nominal diameter" . The torque specs for fine thread are listed differently from coarse threads in the charts.

My point was, not knowing the OP or others who may read this thread, to make sure they understand the proper dimension to use. I've seen it in the forums and I encounter it with new guys at work. Some people think that a hex head bolt requiring a 7/8" wrench is a 7/8" bolt. That could lead to severely overtorquing a fastener and damaging things.

 

[MikeG]

Actually, it's the shank diameter and the number of threads. So, 1/4-28, as and example, is a 1/4" shank with 28 threads per inch. The threads are not always the same outer diameter of the shank size. So, it's better the go by shank OD than thread OD.

The listed size is MAX diameter, generally. Usually the bolt or fastener is a touch smaller than the nominal size, for a variety of reasons. Easier to cut the threads if it is a touch on the small size, and far less likely to have issues with a standard size nut. So a 1/4" bolt generally runs .230" - 0.245" or so, instead of exactly a quarter inch.

Strength of the fastener is based on the minor diameter of the thread. Thus, fine thread fasteners are rated as stronger than coarse thread fasteners, all things being equal.

 

[sgtsandman]

You are both correct. I have seen some fasteners where the OD of the threads were larger than the shank size and others that the OD of the threads were smaller. Not your typical fasteners for sure but they do exist.

The comment about people not understanding that the socket or wrench size doesn't match the bolt size and shouldn't be used as the size to look up torque specs is not wrong either. Nor is the remark about the differences in fine and coarse thread. I was just using 1/4-28 as an example. Probably because that is one of the more common sizes I work with on the aircraft.