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Old 03-07-2014, 02:27 PM   #147
andrew20195
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Quote:
Originally Posted by Element Tuning View Post
I think you're misinterpreting the technical document as it does not use the "engine valve springs." They are talking about the spring in the "spool valve." There are actually a number of springs in the variable cam timing mechanism of the FA20.
I'm quoting directly from the Subaru Technician Reference Booklet on the chain driven engines. Like I said, it's the only source I can find with this info, but seeing as how closely Subaru engineers are involved in technical training, I'd be surprised if they got it wrong.

From my earlier post:
Quote:
The new system does not depend on a hydraulic rotor to function. Instead oil is moved from
one chamber to the other which reduces the volume of oil needed to operate the AVCS.
and

Quote:
A spool valve pressed into the Camshaft rotor controls the oil flow into and out of the Advance
and Retard chambers. The force needed to rotate the Camshaft within the Camshaft sprocket
is delivered by the valve springs.
The oil in the sealed chambers holds the Camshaft rotor into a fixed position. If oil is transferred
from one chamber to the other, the Camshaft rotor and Camshaft rotate within the Camshaft
sprocket.
All the springs shown in the Toyota document appear to be check valves from what I can see.
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