Bolts

Like so many things, 2 steps forward, 1 back. Fuel pump went bad so ordered the correct dual action from Walcks since the one on was single. Pulled the old one in advance to be all ready for when new arrived. Had problem getting bolts off because socket wouldn't really fit but managed to get it. So after FedEx arrived yesterday, I headed out that evening and discovered the bolts were not really buggared up 1/2" but were metric. And of course too short for the new pump. Now to chase down correct bolts. I know I could go to the hardware store but their shinny ones just don't look right. Where is the best place to get 'correct' 1/2" auto bolts other than finding a junk yard?

 

I suppose I would start by looking for Grade 5 or Grade 8 fasteners.

Even my local hardware has those, in the small drawers for specialty items.

Grade 8 Assortment. Bolts,Lock Nuts & Washers 1/4-20 5/16-18 3/8-16 (240 Pieces)

 

electric pump and blanking plate fixes all kinds of problems.

 

5/16 ? That seems pretty small. I don't really know what it is supposed to be since I don't have the original, unfortunately. PO's jerry rigging gets irritating. I'll dig thru my leftover bucket to see if I find something first.

 

I think there might be some confusion here. Bolt sizes go by the threaded section, not the bolt head size. A 5/16"-18 x (Length) will generally have a 1/2" hex head, but may be 9/16" in some cases. That same 1/2" head is very close to 13mm metric, close enough that either wrench works.
You need to determine what the thread in the engine block is. It should be 5/16-18 (coarse thread), but with the age of our Jeeps, there is no telling what a previous owner has done.
Most good hardware stores or a NAPA store usually carry a selection of automotive quality bolts, usually grade 5 (three slashes on the head) as a minimum. 5 slashes on the head denotes a grade 8 bolt which is likely overkill for a fuel pump mounting, though they will work.
I hope this helps.
-Donny

 

If you want not-shiny bolts, you can buy black oxide finish bolts from McMaster-Carr or Fastenall. But the minimum quantity may make it too expensive.

 

If you're worried about "shiny" bolts take a couple proper sized bolts heat the heads with a propane torch, not to red hot or too hot to mess up the temper and drop them in some used motor oil. that will give them a nice aged patina.

 

The local body shop supplier can get or will have black bolts.

 

I always wonder how some people have a problem finding bolts and parts. I can drive 5 blocks and get any bolt, nut or tool I need. Another 5 blocks and I can get about any bearing, O ring, hose or seal I might need. I suppose that living in a stinky cow town has its benefits. Lots of farmers, trucking places and the oil patch folks around. My closest FLAPS has books l under the counter still. I've dealt with that FLAPS for over 40 years for a reason. Sometimes I walk in and see somebody getting the books out as they know that what I want isn't going to be in the computer. I don't know, those old books must be worth a fortune to the right people.

 

Yes, I was referring to the head. I assumed all 1/2 head were a certain size and all 9/16 were a different size. The 1/2 would not get it off so had to use a 13mm, which first perfectly, thus my determination of it being metric (plus it was not an old style bolt but a new shinny zinc platted looking.

 

I buy bolts by the pound at Tractor Supply.

 

Yeah, I have several bags of them out in my shed.. Strange, but a person can grab a bolt out of a tray and I can tell them if it came out of a '51 Chevy or a later Volvo. I can't find my phone sometimes.

 

Generally, but not always. So you want to be sure. Use this project as a start to a life-long process of learning about threaded fasteners. It will serve you well in the future. I'm like uncamonkey, can tell by sight, but usually check anyway.

A couple of items I keep in the handiest tool box draw is a diameter template and a thread pitch gauge. With these two you can determine for sure what you have. Don't be that guy that torques a metric bolt into a inch thread hole in a block.

http://dmpfasteners.com/shop/images/boltgauge_top.jpg
http://images.toolbank.com/images/extralarge/FAIPITCHMA.jpg

 

What screws me up is a vehicle that is both metric and SAE I don't have any of those old British sized sockets out there but I have a few friends who have them.
They haven't used them in decades either.

 

x2

 

Those old "British sized"... I guess your refering to Whitwoth? I still need them from time to time.
-Donny