Date: Tue, 5 Sep 1995 07:37:44 -0700 (PDT)
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: tfab@netcom.com (thom fitzpatrick)
Subject: Early Engine Governors Figgered Out
OJ!
I dunked two of the engine governors in Chem Dip after taking them
apart, and cleanep 'em off last night to have a gander.
The units in question are marked 28 1,5 FDR in big letters on the
cover. This would appear to coincide with the 28 PICT carb. I've
forgotten who made the g'vnor - their logo is pressed on it. The 1,5
designation is stamped rather than pressed on the cover, which leads me
to believe its some sort of "capacity designator" or model #; ie maybe
there is a 2.0 or 2.5 model, just for argument. The 28 FDR is pressed in
the cover, looks like part of the pressing itself.
Now that I have them cleaned up, I've figgerd out how they work.
The governor is installed between the carb and the intake manifold,
using longer studs. It is about 1/4" "thicker" that the cast aluminum spacers
they sell to clean the generator.
The throttle body, if you will, of the g'vnor is square, and has a
square butterfly, or throttle plate, which is attached to one edge of the
body, and not pivoted in the center like a carb would be. It seems like
it would restrict air flow somewhat just at rest! Anyway, the other interesting
thing is the throttle body and bitterfly are _square_, which I thought
unusual.
The plate opens upward. From what I can tell, when flow reaches
a certain point, it pulls the plate down, thus restricting it further. Hence
the need to have it obstruct the stream a bit - so it can "catch".
The plate is countered by a spring and cam controlled lever. The
spring both pulls the plate back, and is also a means to control how "early"
the governor kicks in. The spring tension is controlled by a square nut
on top of the g'vnor, which tightens or loosens the preload on the spring.
There is another needle screw, which appears to set a certain amount
of "pre-restriction" for the plate.
The cover of the g'vnor is made of a thin sheet of aluminum with
a slight convex bulge in it. The screws that affix it to the unit have holes
in them, and a wire is run thru them and a lead seal used to clamp the wire,
to make tampering evident. Also part of the cover is a small clamp for the
adjusting screw on the top (which controls spring tension) which just goes
around the bolt to keep it in place and from being tampered with. There is
no tamper proof mechanism for the needle pre-governance screw.
I'm going to hook this baby up when I get a chance, just to
see what happens. Gotta get some longer studs, first.
Saw one of these units, brand new, at the show for $75. The guy I
bought it from didn't really know what it was, but sold me all three he had
for $12. After dunkin' it in chem dip for a day, it looks almost brand new.
$75 anyone? :)
Thom
--
> Double your drive space - delete Windows!
Thom Fitzpatrick
tfab@netcom.com
ftp://ftp.netcom.com/pub/tf/tfab/home.html
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