Valjoux 7734 30mins to 45mins

[Danh]

Hi guys

does anyone know anything about converting a 7734 30 'min chrono into a 45min counter please

I have found a couple of forum hits, but no definite answer

thanks

[praezis]

You will have to change the min. recorder wheel (from30 to 45 teeth). 

But adjustment is more delicate.

Frank

[Danh]

Thanks Frank

i found the info also, finding the parts will be harder (at a decent price)

8000/3 bestfit X5942 Chrono Seconds Gear 
8040 bestfit X5944 Chrono Minute gear 
8120 bestfit X5924 Sliding Gear

[RyMoeller]

53 minutes ago, praezis said:

You will have to change the min. recorder wheel (from30 to 45 teeth). 

But adjustment is more delicate.

Frank

Yeah, looking at the tech sheet it seems like the only work needed is to swap out the 30 minute recording runner (8020) with a 45 minute recording runner (8040).

I've never done this myself.  Be sure to let us know how it goes. 

[Danh]

3 minutes ago, RyMoeller said:

Yeah, looking at the tech sheet it seems like the only work needed is to swap out the 30 minute recording runner (8020) with a 45 minute recording runner (8040).

I've never done this myself.  Be sure to let us know how it goes. 

Looking on Cousins they list the sliding gear with a 45 minute version also #8120

as other places also list the 8000/3 for a 45 min conversion too (listed at the bottom of the parts guide)

its all adding up to $120 so far

[RyMoeller]

2 hours ago, Danh said:

Looking on Cousins they list the sliding gear with a 45 minute version also #8120

as other places also list the 8000/3 for a 45 min conversion too (listed at the bottom of the parts guide)

its all adding up to $120 so far

Ah yes, good catch.  It looks like the sliding gear changes from part 8100 to 8120 and the chronograph runner changes from 8000 to 8000/3.  It makes sense why the sliding gear would need to be changed...  I'm hitting my post-caffeine wall though which is causing me to scratch my head when it comes to needing to change the chronograph runner.  Probably it just has to do with tighter tolerances.

Glad you've had your glasses on during this exercise though.  Best to figure out all the needs upfront than to be surprised later.

[Danh]

I don't think I can claim any prize for that one - I just reading forum posts on websites and typing numbers into search boxes

At least you know what they I do, I won't know that until I have the old parts (30 second) in my hand - or until I have analysised it properly

Very grateful for your help

cheers

dan

 

 

[Danh]

I have found the parts, luckily in Europe so I don't have import duty to contend with

I have been checking the service guide PDF, I see what is meant by setting up, I am excited by that, it looks like a good challenge

I believe its these parts

I will post images - maybe a walkthrough,  when i do it

[Ratubbs]

Any updates on this ? I’m looking to do the same thing .  I’d like to have a concrete answer as to which parts I need to source .

 

[Danh]

Yes - the parts mentioned did the job - easy to do and worked well

[Alwaysheee]

Gents,

thanks for this! What about converting 30 min to 15 min counter? Do I also need to swap out those other two parts? Thanks