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rear alternator bolt/stud thread size?

4K views 5 replies 3 participants last post by  Lumpy 
#1 ·
i lost it and cant figure out what size i need.

i have tried every tap i own, including metric. closest i can fit is M8 x 1.25 but even that one isnt right.

some sources say M10x1.5x20 but thats huge.

mine was a stud with a locknut on it. my alt sits crooked without it

95 1st gen

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#5 ·
i wish they would have chosen either metric or imperial rather than a whatever combo of either and who knowsits. makes it difficult.

also your response shows you are intolerant of transgender threads or something............#cause remember?
 
#6 ·
Coaster said:
i wish they would have chosen either metric or imperial rather than a whatever combo of either and who knowsits. makes it difficult...
Didn't they? Most common thread on the van is probably M8-1.25, probably followed by M10-1.5.

Generally, everything ON the engine block is SAE. Generally everything else is metric. I suppose Diff bolts are one exception. Some of those are 5/16 others are M8-1.25. The thread PITCH doesn't seem to vary. ie I don't think there are any M8-1.25 AND M8-1.0. There might be somewhere but I don't think I've run across it.

Simpler, for me, is to just look at each bolt size as "the one that fits here". I'm not picking from a hundred different bolt sizes. I'm picking THAT size bolt right there because I know it fits the part.

Like lug nuts. Instead of thinking "What size nut do I need?" I simply think "I need THAT nut right there". It could be 1/2-20 or 14mm or who cares. It's the lug nut. I took it off 15 min ago and placed it right THERE next to the tire so I know where it goes.

Measure, clean, MARK and photograph the bolts as you remove them. I slip every bolt into a thread checker, then wire brush it, then apply blue painters tape and label it "M8 ALT REAR" or whatever. If I was doing an alternator or PS pump or something with tight clearance, I'd check for size, test fit and label which bolt will end up where, including driver size. And use the bolt or a tap to clean up the threads in the pump housing. I don't want to be test fitting bolts once the thing is in place. Too easy to cross thread or drop the bolt.

Lump
 
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