[Roadsters] Differences in carb damper - Figured out

[kendelmccarley at cox.net]

Of course they do.  Like I said in my earlier post, when I switch dampers back and forth between the carbs, the behavior moves with the damper.  That would indicate the difference in the damper length causes the change as that's the only variable in the equation.


---- Bubba <bubwin at mts.net> wrote: 

=============
Do both carbs have the same viscosity oil in them?

Bob Winslade
1966-1600 Missy
1967-1600 Bender

----- Original Message ----- 
From: <kendelmccarley at cox.net>
To: <datsun-roadsters at autox.team.net>
Sent: Sunday, October 21, 2007 12:44 PM
Subject: Re: [Roadsters] Differences in carb damper - Figured out


> Okay, answering my own questions here.  After posting, I had a few ideas 
> on how to debug things.  First, I figured out that if I don't thread the 
> longer rod all the way in so that it's effectively the same length as the 
> original, the carb pistons rise and fall the same way.  With that in 
> place, the car started and idled, but would stumble on acceleration.
>
> Hmmmm..... why the stumble?  Well, in an attempt to find out why, I then 
> screwed the longer damper all the way in.  The piston with the shorter 
> damper was opening much quicker on acceleration, so I stuck a finger in 
> that carb against the piston to slow it down.  Aha!  Now, the engine 
> accelerates nicely.  Take my finger off so that the piston opens quickly 
> again and it goes back to stumbling.
>
> Conclusion?  The one damper that came with the car is wrong.  Man, oh man. 
> These old carbs are so cool.  I've messed with SUs on British cars, but 
> these, while similar, are different and fun to play with.
>
> Joe, do you have another one of those dampers and caps in your stash?
>
>
>
>
>
>
> ---- kendelmccarley at cox.net wrote:
>
> =============
> I've been working on getting a '70 1600 running that was missing a damper 
> and cap from one of the carbs.  Joe Russo was kind enough to fish one out 
> of his stash to sent me but, after installing it, the car still runs 
> poorly.  I pulled the air cleaner to check the rise and fall of the carb 
> pistons.  Sure enough, one of them was much more resistant to movement 
> than the other.  When I switched the dampers from carb to carb, the one 
> with Joe's part was harder to move.
>
> The only difference I can see between the two is that the one Joe sent me 
> is around a sixteenth of an inch longer, putting the damper part farther 
> down into the carb.  How does this make a difference?  If I mod the new 
> part to be a bit shorter (pull it out of the cap, cut it down, and 
> re-insert into cap) will that cure this problem?
> ________________________________________
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