# 65 389 Alternator Belt Adjustment Arm(s)



## SLSTEVE (Dec 8, 2020)

Is there one or two belt adjustment arms on a 65 389 engine? I actually had two in my pile of parts, one that bolted to a water pump bolt and another that looked like it bolted to the thermostat housing. Do you use one or the other, or both? Tried using both at one point but they didn’t line up nicely together, so I went with the WP one and left the TH one off.


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## armyadarkness (Dec 7, 2020)

You use both.


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## armyadarkness (Dec 7, 2020)




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## SLSTEVE (Dec 8, 2020)

And they both go BEHIND the mounting boss on the alternator! Guess that as my alignment problem.


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## Roger that (Feb 6, 2010)

For 1965 Power steering equipped car used two alternator brackets. Non-power steering cars used one alternator bracket.


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## SLSTEVE (Dec 8, 2020)

armyadarkness said:


> View attachment 146578


Thanks Army! Appreciate it!


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## armyadarkness (Dec 7, 2020)

No problem. It's so rare that I know what Im talking about!


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## SLSTEVE (Dec 8, 2020)

armyadarkness said:


> No problem. It's so rare that I know what Im talking about!


Ha ha ha! That sounds more like me! Can’t believe I couldn’t figure that one out on my own. Did get them both hooked up. Looks good.
Now I’m trying to get my side windows in. Passenger side quarter window’s regulator needs replacing, as the tiny screw hole at the bottom channel is broke right at the thread. This is the hole that the vertical trim’s attaching screw gets screwed into. Can’t figure out a way to fix it so I’m buying a replacement,


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## SLSTEVE (Dec 8, 2020)

Roger that said:


> For 1965 Power steering equipped car used two alternator brackets. Non-power steering cars used one alternator bracket.


Thanks Roger that!


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## SLSTEVE (Dec 8, 2020)

SLSTEVE said:


> Thanks Roger that!


Added the other arm. Not lined up perfectly, but looks like it will do the job.


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## armyadarkness (Dec 7, 2020)

It'll work. I wouldnt be afraid to increase the bend on the arm if you needed to


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## tallrandyb (Jun 12, 2021)

I kept snapping the support bolt off for my alternator with PS and only one bar, they must have lost one at one point before I originally bought it. Kept searching for and replacing the bolt with stronger and stronger material, didn’t really have any way to search for how the alt should be supported back in early 80’s so figured there was only one bar.

now I see these second bars and realize what the problem was. May have had some misalignment too, what did I know I was a kid. Currently have 2 bars and PS and good alignment.


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## SLSTEVE (Dec 8, 2020)

tallrandyb said:


> I kept snapping the support bolt off for my alternator with PS and only one bar, they must have lost one at one point before I originally bought it. Kept searching for and replacing the bolt with stronger and stronger material, didn’t really have any way to search for how the alt should be supported back in early 80’s so figured there was only one bar.
> 
> now I see these second bars and realize what the problem was. May have had some misalignment too, what did I know I was a kid. Currently have 2 bars and PS and good alignment.


Thanks for taking the time to respond. Bought this car as a roller body and a couple of boxes of parts. This is my first venture into Pontiac’s so I am not aware of their idiosyncrasies. I tried to put both arms on a few times, but couldn’t figure how they went, so just went with the one bolted to the water pump. Never thought of aligning both BEHIND the alternator boss! Guess my mechanical abilities are evaporating with age. Anyway, thanks to Army, I have everything hooked up as intended by the engineers at Pontiac Motor Division.


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## tallrandyb (Jun 12, 2021)

Make sure to install a vented PS pump cap, mine was leaking from pressure until I replaced with a correct one.


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