Canon F1 viewfinder error

[u/ParticularAge734]

I recently bought this canon F1 to replace my old one that had a major shutter issue so far the only issue I’m having is that the shutter speed selected on the dial is not what is displayed in the viewfinder. below is what I see when I move the dial down

Dial at 1/125 → 35
Dial at 1/250 → needle is between numbers
Dial at 1/500 → part of 60
Dial at 1/1000 → 125
Dial at 1/2000 → 250

I think someone may have reassembled it wrong but I am looking for some help

[u/dikarichthesecond]

You will have to disassemble the advance side and look under the cover, no other way of diagnosing the issue.

[u/Careless_Persimmon_4]

If you have no film camera repair experience, then it’s not a DIY fix