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1991 caprice 350 2bolt main question

RootBreaker

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so this is what I have in my truck. a very long time ago, I put my front accessories on this motor and converted it from tbi to carb, well before the internet is what it is today or id prolly woulda done tbi upgrade and no clue what I did with all the serp stuff.. ughhh what I know now... go figure..

anyway, it appears I broke the long bolt off the alternator and this has affected my recharging as the belt isn't tight enough.

so yes... drill it, try an easy out or drill and tap it but my question...

was this a metric bolt or standard as I'm wondering if it snapped due to the 78 standard bolt put into a metric hole?
I cant recall that long ago...let alone what I had for dinner last week!
 
I would try a left-hand drill bit I seem to have better luck with those then easy outs
 
I would try a left-hand drill bit I seem to have better luck with those then easy outs

LOL I would of laughed at you for that comment but after searching a bit and hearing that they do exist!!!!! id think you were telling me to use a left handed crescent wrench too!!!

but yes I guess ill have to get a kit with that in it...

I'm still wondering what the actual bolt is though for a 1991.. is it metric or sae?
 
LOL I would of laughed at you for that comment but after searching a bit and hearing that they do exist!!!!! id think you were telling me to use a left handed crescent wrench too!!!

but yes I guess ill have to get a kit with that in it...

I'm still wondering what the actual bolt is though for a 1991.. is it metric or sae?
Should be metric. I think they went metric in 87-88..??
 
It's anyone's guess in my experience--I've seen a mix of SAE bolts AND metrics on GM's built since 1978 or so...my 1982 6.2 has a 15MM head bolt on the alternator ,I assumed it was a 10mm bolt,but I found out it has 3/8"x16 threads in the head...:screwy:...not sure if someone tapped it ,or if it always was that way..other bolts have SAE sized heads and threads,some are metric thread and hex...
 
Do you have a welder ?--if so,you can weld a washer to the bolt and a nut to the washer and unscrew it easy probably..

If not sometimes a LH drill will spin out the busted piece when it snags,the tough part is getting a hole started perfectly on center..
The worst thing is having an E-Z out or drill snap off in the bolt--then your lucky if you can get the remains out--I've used my cutting torch to vaporize them,they will burn like a sparkler before the bolt gets hot enough to melt..

I rarely use E-Z outs after so many "fails"with them breaking or failing to work..I now only use them on pipes that broke off in fittings,any under 3/8" thick snap too easily..


I got lucky a few times and used a sharp punch and a hammer to tap the punch on the outer edge of the bolt and got it to back out..as long as the bolt has not been bottomed out in the hole,or "stripped" by putting a metric bolt in an SAE hole,or vice versa, it should come out fairly easy..
 
GM started painting engines blue around 1976 if I remember correctly,maybe 1978 ?...
 
GM did some crazy stuff in the 80's and 90's, but my crate L31 bolts are standard, as are the Vortec heads I bought a decade ago. I find it hard to believe GM would have drilled and tapped them differently on cars and trucks.

Things like the alternator itself though...I have one (CS130) that is a metric bolt up top for the adjustment, while the bottom bolt that it pivots on, is standard.
 
it don't matter... I cant get a damn drill bit to drill it out. went and bought hardened bits, stuff meant to drill hardened bolts and I just cant get it to drill AT ALL!!!!!

fyi drill is going correct way for some of you smart asses.... :haha:
 
it don't matter... I cant get a damn drill bit to drill it out. went and bought hardened bits, stuff meant to drill hardened bolts and I just cant get it to drill AT ALL!!!!!

fyi drill is going correct way for some of you smart asses.... :haha:


Time to get the welder out.
 
Several customers I sold left hand drill bits to at the parts stores came back an hour later with the tip melted off,and told me "there drills suck,what are they made of ,aluminum ?"...

Most of them had a non reversible electric drill ,it was determined,when I asked "are you sure you had the drill in reverse"?..and I got the "blank stare"..:thinking:

One tip I've found handy--you can use a masonary bit with a carbide tip to drill very hard steel,even ball bearing races--you may need to grind it to a different angle and re-sharpen it,but it does work..
We used that trick at one parts stores machine shop to drill out things like hardened pins ..
 
it don't matter... I cant get a damn drill bit to drill it out. went and bought hardened bits, stuff meant to drill hardened bolts and I just cant get it to drill AT ALL!!!!!

fyi drill is going correct way for some of you smart asses.... :haha:
How fast were you drilling?
Hardened bolts need very low speed and good lubrication
 
Would seem like a lot of work, but what isn't at this point? How about making a plate that bolts in using the other two holes, and has a nut welded to the backside to support the alternator?
 
Would seem like a lot of work, but what isn't at this point? How about making a plate that bolts in using the other two holes, and has a nut welded to the backside to support the alternator?

Ive thought bout that. Busy mon-fri.. weekend to look...


Time to get the welder out.

Ive got the bubbly. Get yer ass ovah heyah
 

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