mgs
[Top] [All Lists]

Re: Overdrive Woes

To: "Mark Herrick" <mgbgt@herricknet.net>, <mgs@autox.team.net>
Subject: Re: Overdrive Woes
From: "Paul Hunt" <paul.hunt1@blueyonder.co.uk>
Date: Thu, 8 Sep 2005 19:29:03 +0100
The Leyland Workshop Manual (of which the Bentley manual is a copy) says
that the broken circlip/worn or glazed linings issue relates to slipping in
reverse on the overrun, not the OD engaging on its own.

The oil pump is running all the time the input shaft is turning in order to
lubricate bearings at low pressure, controlled by a valve.  When the
solenoid operates it closes a port which shuts off the direct path to the
low-pressure valve and allows high pressure to develop and operate the
sliding member.  A tapping off the high-pressure line enters the
low-pressure valve through a different port to continue the supply of
lubrication oil at low pressure.  It seems to me that anything that blocks
the low-pressure line from the solenoid to and through the low-pressure
valve could cause the OD to operate, and if it is only a partial blockage
the pressure could be marginal which explains why it does it sometimes and
not others.  The solenoid may also not be fully moving back into its coil,
which will be one of the easiest things to check.  In fact if you leave the
ball bearing off the end of the solenoid shaft you will completely eliminate
the solenoid as a cause, both electrical and mechanical.

PaulH.

----- Original Message ----- 
> ... the Bentley manual indicates
> a broken circlip or worn od clutch linings...




<Prev in Thread] Current Thread [Next in Thread>