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Re: Alternative gear lubes

To: A666K@aol.com, spitfires@autox.team.net
Subject: Re: Alternative gear lubes
From: Dean.Dashwood@enron.com
Date: Fri, 12 Jan 2001 09:29:13 +0000
Avi,

As Donald said, you shouldn't be able to use O/D in 1st or 2nd gear - it's
not designed to work.  The power to the O/D switch should be routed as
follows: 12V -> little switch on top front of gearbox -> O/D switch ->
solenoid -> ground (via the gearbox).  It sounds like you're missing the
little switch on top of the gearbox - it's called an Overdrive Inhibitor
Switch.  It's normally open, and it's activated (closed) by a lobe inside
the gear shifting mechanism which only operates in 3rd and 4th.

If you are missing this switch, whatever you do, DO NOT engage O/D in
reverse!  This could permanently bugger your O/D.

Just a thought here - you said you'd done an O/D conversion....  Did you
get an O/D gearbox, or did you modify your existing gearbox?  I don't know
this, because I've never seen one, but is it possible that the non-O/D
gearbox doesn't have anywhere to mount the inhibitor switch?  If that's the
case, you might like to do something similar to what I did when the lobe
that activates the switch wore down and I didn't feel like tearing the
gearbox apart to fix it.  I wired a normally-closed relay (appropriately
rated for the high currents that the J-type draws) in place of the
inhibitor switch.  Then I connected the reverse-light feed to the relay, so
that when the reverse light is on, the relay opens.  I can now activate O/D
in 1st/2nd, although I tend not to because it's not good for it, but the
relay prevents me from accidentally using O/D in reverse.

Hope that helps - good luck!

Dean
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Date: Thu, 11 Jan 2001 21:50:16 EST
From: A666K@aol.com
Subject: Re: Alternative gear lubes

In a message dated 1/11/01 7:26:04 PM Eastern Standard Time,
mikeginter@frii.net writes:

<< Yes.  Never put synthetic in an OD trans that requires friction to
 operate. >>

So how do I recover my friction surfaces from their slippery state? I have
non-synth. in it now, still slips when I try to accelerate hard in 1st and
2nd while the tranny fluid is cold (the engine is warmed up, of-course!).
Help! Have I ruined my OD?
Avi

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