[Healeys] overdrive problem

[Bob Spidell]

Maybe of interest to some: AFAIK, all O/D accumulators came with metal 
rings, which likely cause or at least contribute to scoring. One of the 
Brit suppliers--probably AHS but I'm not sure--has an accumulator setup 
that uses an O-ring(s) instead of metal rings, which should prevent 
scoring. I rebuilt my O/D a couple years back, and if I'd known of the 
O-ring type I would have installed it. Earlier O/Ds used metal rings in 
the actuator pistons, but later ones had O-rings, and it's logical to 
conclude LdeN went to O-rings there because of excessive scoring of the 
cases (or, possibly, because they were cheaper).

On 3/26/2021 6:03 AM, Michael Salter via Healeys wrote:
> Time this question was put to bed.
> 1. The throttle switch is not supposed to disengage the overdrive if 
> the dash switch is in the "OVERDRIVE" position. If it does the system 
> is wired incorrectly. (BN1s are a little different)
> 2. Overdrives which slip out, slip, or won't engage WHEN HOT but do 
> work when cold are invariably suffering from low oil pressure which is 
> almost always caused by accumulator issues.  The "O" rings on the 
> outside of the accumulator sleeve can be a problem but in my 
> experience scoring of the accumulator bore and damage to the rings and 
> piston are a more common cause.
> 3. Overdrives and gearboxes in Healeys are meant to be lubricated with 
> engine oil. Decades ago I  wrote to Laycock DeNormanville, back when 
> letters went in envelopes with stamps, and received a  response from 
> their engineering department indicating clearly that the oil specified 
> for their products was specified by the gearbox manufacturer and 
> whatever they specified was acceptable for the overdrive.
> M
>
> On Fri., Mar. 26, 2021, 2:13 a.m. WILLIAM B LAWRENCE via Healeys, 
> <healeys at autox.team.net <mailto:healeys at autox.team.net>> wrote:
>
>     The symptoms I’ve seen and experienced are that the OD will engage
>     and function until the oil temp comes up and the viscosity drops
>     off and will then fail. I suppose it depends on the degree of
>     degradation of the o-rings.
>     ------------------------------------------------------------------------
>     *From:* Healeys <healeys-bounces at autox.team.net
>     <mailto:healeys-bounces at autox.team.net>> on behalf of Bob Spidell
>     <bspidell at comcast.net <mailto:bspidell at comcast.net>>
>     *Sent:* Thursday, March 25, 2021 11:14 PM
>     *To:* healeys at autox.team.net <mailto:healeys at autox.team.net>
>     <healeys at autox.team.net <mailto:healeys at autox.team.net>>
>     *Subject:* Re: [Healeys] overdrive problem
>     Sure, but wouldn't faulty O-rings prevent the OD from engaging in
>     the first place? Just guessing, but wouldn't a deficient pump
>     cause same symptoms?
>
>
>     On 3/25/2021 4:07 PM, WILLIAM B LAWRENCE via Healeys wrote:
>>     Sorry, but the Laycock deNormanville overdrive is not supposed to
>>     kick down automatically. The most common fault that causes the OD
>>     to drop out is faulty o-rings on the accumulator sleeve. This
>>     won’t allow the OD to build full operating pressure.
>>
>>     Bill Lawrence
>>     BN1 #554
>>     ------------------------------------------------------------------------
>>     *From:* Healeys <healeys-bounces at autox.team.net>
>>     <mailto:healeys-bounces at autox.team.net> on behalf of Kees
>>     Oudesluijs via Healeys <healeys at autox.team.net>
>>     <mailto:healeys at autox.team.net>
>>     *Sent:* Tuesday, March 23, 2021 7:37 AM
>>     *To:* healeys at autox.team.net <mailto:healeys at autox.team.net>
>>     <healeys at autox.team.net> <mailto:healeys at autox.team.net>
>>     *Subject:* Re: [Healeys] overdrive problem
>>     That is the way it should be when accelerating hard, Kick down!!
>>
>>     Kees Oudesluijs
>>
>>
>>     Op 23-3-2021 om 01:06 schreef healeymanjim via Healeys:
>>     > friends BT7 had o/d quit.  solenoid was bad so replaced it. 
>>     now it will go into o/d but pop out when accelerating.   any
>>     > ideas what the cause is and the fix?
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20210326/a87e71f6/attachment.htm>