Albert,
I believe David is right, the actual recommendation is to use engine
oil. I've heard and/or read about all the others also (ATF, power
steering, special dashpot oil, etc...) I am currently still using the
special dashpot oil I bought from Moss in my SU HIF44. Grass Roots
Motorsports did some kind of dyno comparison of different oils (even NO
OIL) last year in an MGB and found no measurable differences in
performance. That doesn't correspond with my personal experience though
since I recently replaced the carb and forgot to put oil in it. Didn't
accelerate too well (too lean). A quick fill-up helped the problem. I
believe you are supposed to fill the chamber to about 1/4 inch from the
top, which is about the height of the little piston. If you shine a
light in there, you should be able to judge the height of the oil while
filling. More oil than that will be displaced by the piston and forced
out of the chamber. As a side note: "Car Talk" on NPR recommended using
ATF to a TD owner who called in last week. One of the brothers (Click
or Clack?) happens to own a TD. Not sure that they solved the caller's
problem though.
Donny V
1978 MGB (with SU HIF44 conversion)
>>> David Councill <dcouncil@imt.net> 5/27/2004 10:31:18 AM >>>
Whether ZS or SUs, I have heard people use ATF, Marvel Mystery Oil (I
think
that is what it is called), mineral oil, and just regular motor oils. I
used to use a light mineral oil for many years but after I bought my 67
BGT, I found the damper kept coming unscrewed after 10-20 miles, no
matter
how tight I tightened it. After replacing the damper and even the
dashpot,
I still had the problem but going to regular motor oil fixed it. I
believe
the actual recommendation is to use the same grade motor oil that the
engine is using, probably meaning 20-50 or 10-40.
Still, the bottom line is that the fancy dashpot oil is a waste of
money,
as you can see.
David Councill
67 BGT
72 B
At 09:54 AM 5/27/2004 -0400, Aeseeyou@aol.com wrote:
>Hi,
>I was having a heck of a time trying to get a smooth throttle response
when
>taking off from a stop sign in 1st gear. I finally figured it out that
the
>throttle damper was probably dry or low on oil. So I unscrewed the
black
>plastic
>cap and carefully lifted the cap, rod & damper (all 1 assembly) out of
the
>Z-S
>carb (1978 MGB) then after the entire cap & damper had been pulled out
I
>carefully put it (cap & damper) back in, there was absolutely NO
>resistence when I
>pushed the damper in. Having been told that this indicated that there
was
>little or no oil in the chamber I called my pal and asked our club
>President Don
>Cole (who just happens to be an excellent auto mechanic, by the way!)
about
>what type of oil I should put in the top of the damper opening since I
didn't
>have any of the Zenith-Stromberg or S-U oil. He said that ATF could be
>used in
>place of the S-U type oil that is sold in the major parts dealers
>catalogs. So I
>put in about a 1/4 teaspoon (maybe less) and Viola! There was now
strong
>resistance when I pushed the cap and damper in. I then screwed the
black
>plastic
>cap back on. Now, the throttle response is smooth although I'm sure
that a
>tune-up (clean or replace the spark plugs, etc.) is going to be next.
I just
>thought I'd write to tell you the hint about being able to use ATF
(automatic
>transmission fluid) in the throttle damper chamber, in lieu of having
the
>Zenith-Stromberg Dashpot oil, an excellent product, by the way, which
>costs approx.
>$8.00 plus S & H for a 125 ml. an amount that should last you a long
time
>if used
>normally. But, like I said earlier ATF (or power steering fluid) will
also
>work if that's all you can find. Any comments?
>Albert Escalante, owner 1978 MGB roadster
>The Central Coast British Car Club (CA.)
>Ventura, Calif. (www.ccbcc.org)
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