Hi Guys
New to the forum, although have been reading for some time. Will send through an introduction post when I have some time but want to open with a query.
In my seemingly never ending quest to keep my B10 in original condition, I have recently noticed that the counterweight is missing from the exhaust manifold (original engine with the later style exhaust manifold). Looks like the spring has also seen better days; forgot to check if the pivot pin is on the inlet manifold.
I have found one for a A12 engine from a 1200 but am unsure if it is the same setup.
It would be appreciated if someone would be able to shed some light on the matter as I have made tentative arrangements to purchase the manifold from the A12 but dont want to get stuck if it is not the same weight.
If it is different, would anyone out there have an original for an A10 manifold?
Any help would be appreciated.
Thanks again, and will post an introduction soon. Thanks also to Ashley for his direct help in the past.

do you have a pic of the replacement manifold? it should work as is even if its different
they work in the same manner. Might just have some small design differences in outer cosmetics

As long as the carb manifold has the same trapezoid pattern
(sorry but cant check anymore as Im 1000 less for almost 3 years)
Also the 2 bolt flange should be the same but just check that as well
as you can reuse you flange seal if its not too deteriorated and just
add a swipe of the cheaper clear silicone then it will work as original

I cant concur unfortunately, please ask in our brother forum datsun1200.com
specifically to DDGonzales who is the champ of A series interchangeability 
and reference material. He loves these challenges!

what is that counterweight for?
 
I dont think I have ever seen that before.
None of my 1000 stuff has it?
 
Is that a bi metal spring that moves once it reaches temp?
So its open when the motor is cold to heat up the intake and the incoming air, but once warm, it closes the flap and reduces the heat transfer to the inake manifold.
 
All my 1k manifolds that bolt together have the intake and exhaust permantly together with a gasket to seal the exhaust at the junction.
 
You could eaisly ditch it and it would not have a noticable effect on its warm running. It would be fine for cold startup.

Hi Dundee1000
Many thanks for the reply/info. Unfortunately I missed the ebay item as I let it slip as I wasnt sure it was the same part. Would anyone have one available?
While Im not going for a full restoration, I do like my cars to be as near to 100% original/correct as I can make them and small things like this annoy me.
Thanks again for the info. If someone could help out with one it would be appreciated.

Hi Ashley
Many thanks for the help (again). Looks like the beast Im after; have asked the seller for a closer photo of the area in question so I can look if the beast in question looks ok.
Will let you know how I go. Pretty sure it looks ok from the photos provided in the listing.

Received the photos from the ebay seller; all looks OK. Have purchased it.
Another piece to the puzzle.
Thanks again for everyones help; will get around to a formal intro post soon.