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Discussion Starter #1
So I put some gear oil in my transmission and spun the motor up with
a 12 v battery.

Much to my surprise even when the gear shifter appears to be in
neutral, the drive shaft still spins (note that the shaft is
disconnected from the rear differential).

Its a 5 speed Nissan transmission from a 86.5 nissan pickup, and
prior to beginning this conversion I knew nothing about cars. Do any
you you more experienced mechanic types have any thoughts how the
gear shifter can appear to be in neutral but the transmission is not?

A few months ago prior to reconfiguring my component/battery
placement the transmission was acting normal as I back in and out of
the garage under battery power.

The other weekend while we had visitors over I spun the motor for a
short time without gear oil in the transmission (less than 2 minutes
in total and the shifter was in neutral position). Did I manage to
trash my transmission?

John

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Discussion Starter #2
The fluid in the transmission is likely acting as the transmission itself.
It's a fairly week action and you could likely stop it by grabbing the
driveshaft with your hand (but I don't recommend that). It's normal in many
transmissions, but I can't confirm if that is the case with your Nissan.

- Kip

----- Original Message -----
From: "John" <[email protected]>
To: "Electric Discussion List Vehicle" <[email protected]>
Sent: Thursday, August 30, 2007 8:01 PM
Subject: [EVDL] No neutral??


> So I put some gear oil in my transmission and spun the motor up with
> a 12 v battery.
>
> Much to my surprise even when the gear shifter appears to be in
> neutral, the drive shaft still spins (note that the shaft is
> disconnected from the rear differential).
>
> Its a 5 speed Nissan transmission from a 86.5 nissan pickup, and
> prior to beginning this conversion I knew nothing about cars. Do any
> you you more experienced mechanic types have any thoughts how the
> gear shifter can appear to be in neutral but the transmission is not?
>
> A few months ago prior to reconfiguring my component/battery
> placement the transmission was acting normal as I back in and out of
> the garage under battery power.
>
> The other weekend while we had visitors over I spun the motor for a
> short time without gear oil in the transmission (less than 2 minutes
> in total and the shifter was in neutral position). Did I manage to
> trash my transmission?
>
> John
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.484 / Virus Database: 269.12.12/979 - Release Date: 8/29/2007
> 8:21 PM
>
>

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Discussion Starter #3
Actually that is normal.
The gears ride on a shaft that spins inside the gears. The synchronizer
hubs are splined to the gears and connect the desired gear set to the
shaft. In neutral no gears are selected but the shaft still spins. The
viscosity of the oil will cause the gears to follow the shaft if there
is no load. You should be able to hold the output shaft still and start
the motor. I wouldn't try to stop it if it is already spinning because
the momentum would make it had to stop. Or, with no power to the
motor, you should be able to turn the output shaft by hand while
holding the motor shaft still and vice versa.

Note: I would consult the Nissan manual to be sure you used the correct
oil. Not all transmissions use 90W hypoid gear oil. I'm not assuming
that is what you used. I just mention it because I often see
transmissions die early due to being filled with the wrong oil.

Ken



-----Original Message-----
From: John <[email protected]>
To: Electric Discussion List Vehicle <[email protected]>
Sent: Thu, 30 Aug 2007 10:01 pm
Subject: [EVDL] No neutral??



So I put some gear oil in my transmission and spun the motor up with
a 12 v battery.

Much to my surprise even when the gear shifter appears to be in
neutral, the drive shaft still spins (note that the shaft is
disconnected from the rear differential).

Its a 5 speed Nissan transmission from a 86.5 nissan pickup, and
prior to beginning this conversion I knew nothing about cars. Do any
you you more experienced mechanic types have any thoughts how the
gear shifter can appear to be in neutral but the transmission is not?

A few months ago prior to reconfiguring my component/battery
placement the transmission was acting normal as I back in and out of
the garage under battery power.

The other weekend while we had visitors over I spun the motor for a
short time without gear oil in the transmission (less than 2 minutes
in total and the shifter was in neutral position). Did I manage to
trash my transmission?

John

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