Re: TR6 overdrive.

[John Duhart <duhart@symbol.com>]

Hey Ed,

 I knew this is the type of response I would get (well sort of).  What I am 
saying is not that an OD won't engage in reverse, but that it won't engage in 
reverse unless you are driving at speed (i.e. enough speed to build up 400 psi 
in the OD).  I don't think this would happen if all you are doing is driving 
out of your driveway.

Later,
JHD IV

>>> "Ed Woods" <fogbros@nb.net> 05/18 11:22 AM >>>

Don't tell my '61 Healey 3000 that the o/d can't be engaged in reverse!
Wired the lever into the closed position because the solenoid had failed.
The o/d remained on in all gears, forward and reverse.

I was on the interstate at the time the solenoid failed. Healey's are not
made to be driven at 75mph in fourth gear; hence my temporary fix.

Ed Woods
-----Original Message-----
From: John Duhart <duhart@symbol.com>
To: triumphs@autox.team.net <triumphs@autox.team.net>; bollen@ibm.net 
<bollen@ibm.net>
Date: Monday, May 18, 1998 8:32 AM
Subject: Re: TR6 overdrive.


>
>Hey All,
>
> Ya know, I've seen a lot of people asking this question, and I was
thinking about it this week, and I came to a potentially interesting
conclusion...   The OD CANNOT engage in reverse, unless you are driving at
speed!
>
> Let me explain. (Please rememer I have a self-thought knowledge of the OD,
so if you want to shoot this down feel free).  OK, the OD needs pressure
from the pump to be engaged.  I've read that it needs about 400psi from the
pump to function.  I have read that one of the reasons both the A and J-type
OD's are locked out in 1st gear is because the pump cannot produce that kind
of pressure.  If this is true, then it should also not be possible to build
up 400psi of pressure while drving in reverse out of your driveway, so the
OD will not engage.
>
> Now I can think of two possiblities were you could get the OD to engage in
reverse.
>
>1) You drive in reverse for about a mile doing around 30-40mph.  This may
build up enough pressure
>
>2) While driving down the highway you decide to through it into reverse to
see what will happen, and forget to shut-off the OD.  (Of course your OD
exploding will be the least of your problems!)
>
> Anyway I think this is why we have seen people reporting they have driven
in reverse with the OD on without destroying it.  These people were only do
a short drive (i.e. out of the driveway), and at a very low speed, so the OD
pump couldn't build up pressure to 400psi, and so the OD WAS NOT engaged.
>
> What does everyone the.
>
> (Yes another complex problem solved in the shower!)
>
>Later,
>JHD IV
>
>>>> Bollen <bollen@ibm.net> 05/16 7:42 PM >>>
>
>Today I tried to reverse with the  O/D engaged. Luckily it does not seem
>to have done any damage. (J type).Is there supposed to be any kind of
>electrical lockout when reverse is engaged? I never did this before,
>wondering if a wire has come off somewhere.
>Stu
>74 Tr6 80 TR8
>
>
!
>
>

                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                               
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
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