F150online Forums - Bolt Size ? ?

F150online Forums (https://www.f150online.com/forums/)

- Pre-1997 Models (https://www.f150online.com/forums/pre-1997-models-51/)

- - Bolt Size ? ? (https://www.f150online.com/forums/pre-1997-models/474825-bolt-size.html)

Ref: 1991 4.9cyl Starter

I'm removing the bolt the Ground cable is under on my Starter, and of course it Breaks. :eek: ALL I wanted to do was clean it up in hopes the bad ground is my No Start issue, NOW THIS! :scared:

Well I drill and "try" using stud removers(no success) and Drill and it seems to go THRU the entire stud, for I feel it give on the back side, then of course bump into the motor case. ANYWAYS, my question, Any way of knowing for sure what Bolt Size I need? I Measured the little piece that I broke off, and any bolt at the auto store is a tad to little or tad to big. I bought BOth, but now I got them all to Long. Drilling through it seems to be just 1/2" at the most. SHORT little stud for sure.

The Head fit 1/2" perfect. Seems like 5/16 bolt maybe 18 thread. But the 5/16 are .30 on the caliper, mine is .33, big diff.
Thinking I'll have to buy a Tap set to rethread it, cuz I can't get the little bit left to screw out even with a nice craftsman ScrewOut piece. So I gotta keep drilling, which will eat the threads.

BOLT SIZE Anyone? Where to Find it? :think:

Thanks:beers:

Or the block is the block is the block, and find another handy place to put your ground.

Adrianspeeder

True Enough, and I appreciate it. But I'm still left with a broken bolt to which size I'm unsure. Getting a Tap set to this hole is going to be ridiculously hard. Arrrgg..

Thanks

How much of the threaded portion of the bolt do you have?
You say the shank mics .330 but that may be deformation. A 5/16" bolt would mic .3125 and would normally have a 1/2" hex. Remember that a lot of stuff is Metric on newer engines; an M8 would mic .3150 and could have a head as large as .512 (13mm) or as small as .500 (12.7mm.) Nothing is going to have a .33" shank. If you have any of the threaded portion, beg, borrow or steal a thread pitch gage and see what you have. A 5/16" could be 18 TPI (UNC) or 24 TPI (UNF) an M8 will be 1.25 pitch which is just under 20 TPI

Thanks SR. No, the shank doesn't have enough to measure thread pitch. The 1 thread on the bottom appeared to be original thread. But I agree, there was no shank at the auto store with a .33".

I'll be honest, I've never tap'd anything before. And this Hole is in a very hard place. That typical set I see for sale is not going into that space. Ya think I can put it on a drill extension and turn it slow? The other concern is the bolts proper depth. It appears to be maybe 1/2" at the most. Sure seems short.
I'm thinking I'll goto a Junk Yard and see what they have. Maybe I can take on off there. Actually, if I can just remove the bolt clean, I'm GOOD! Heck with the starter, it can remain there with 1 bolt all I care.

OH, did I mention, the Lawn mower wouldn't start and the dryer stopped. I have been fortunate enough to know how to work on dryers, but this time I think it's time for replacement. As for the lawn mower, I felt like supporting the local small business owner and let some guy fix that. LOL!!