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Re: Correction - not camshaft! Rocker arm shaft

To: Howard.Allen@fairchildsemi.com
Subject: Re: Correction - not camshaft! Rocker arm shaft
From: Donald H Locker <dhl@chelseamsl.com>
Date: Tue, 15 May 2001 17:46:58 -0400 (EDT)
The supply to the rocker shaft is regulated in a rather unique manner
-- rather than regulating lubricant flow to the top end with an
orifice (prone to plugging) or the running clearances in the rocker
mechanism (easier to manufacture to looser tolerances), our engine
uses a flat on the rear camshaft bearing which allows oil to pass at
full flow, but only for a portion of the camshaft's rotation.  Kind of
a switching-regulated flow control.  I don't see any problem with this
unless the rocker shaft or rockers are worn, in which case the aft
rockers will be well-lubricated, but insufficient lube will be making
its way forward.

Bottom line:  you shouldn't need an external supply unless the valve
train is worn, in which case repairing that would be more beneficial.

Donald.

> Date: Tue, 15 May 2001 15:01:10 -0400
> From: Howard Allen <Howard.Allen@fairchildsemi.com>
> 
> 
> Sorry about that, I meant the shaft that the rocker arms pivot on (been
> working on Chrysler 2.2 OHV engines way too long!).
> 
> Howard
> 
> Hi;
> All this discussion about oil pressure and the like leads me to ask this
> question.  A few years ago I read a technical article on the basic
> engine design of our engines that stated that there is a weakness in the
> oil supply to the camshaft bearings.  Any comments on the validity of
> this statement?
> 
>  The fix is an accessory braided steel line that goes from the oil pump
> journal line up to the camshaft supply journal, which conveniently has a
> removable plug in it.  (I bought mine from the Roadster factory and
> installed it in about 15 minutes.)

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