PCV Valve For Inline Engines
By Karl Schluter -Low Zep
***As this is an untried system at this
stage, do seek the opinion of a qualified mechanic before proceeding with
this modification! ***
This is a copy of a system you could buy in the 60’s and
70’s to retro fit to cars not fitted with PCV systems. The advantages are:
Cleaner oil
Possible MPG gains
Increased engine life
Removal of condensation and sludge in the rocker cover.
While I have not tried this on my own earlier cars (I do
run one on my performance V8) I would certainly test one on a Consul/Zephyr
engine to replace a draft tube system.
**If your engine is really smokey and has a blow by
condition of more than 15%, you may find a PCV system will not handle the smoke
etc in which case, system number 3 (below) might be of help. **
Mount a PCV valve (from a similar cubic inch sized engine)
to the side plate of the motor. This is a good position for a PCV valve as it
is the factory point for the draft tube and it is also baffled as not to soak
the PCV valve with oil. Earlier cars might need the factory pipe on the side
cover turned upwards. For system 2, 3 or 4 (below in pictures) a steel
line could be bent up like the factory brake booster line to work with the
different systems shown. The idle mixture might need readjusted on start
up. Because a lot of blow by is unburnt fuel, the PCV system could richen the
mixture. However, it could also be lean because of the extra air flow through
the engine, this can also be sensitive to the amount of air that flows through
the oil filler cap, in which case an oil cap from a Ford cross flow motor or
similar, that has a PCV system fitted as standard, might be a good match
up if it fits. Do give the valve a clean every 5000 miles, or at least check on
removal that the valve still rattles and is not gummed up. While a PCV valve is
not always used in this system, I prefer to run one in case of a backfire
through the carburettor, in which case the valve closes automatically.
Picture 1 is the standard system as used
on Zephyr 4 and 6 motors. It does not work below 25 mph.
Picture 2 has the road draft tube plugged
(or removed) and the hose complete with inline PCV valve going
from the side plate mounted draft tube to a spacer plate mounted under the
carburettor (between it and the carburettor).
Picture 3 is a system used in the old days
for motors that are tired or have more blow by than standard. Like the 2
pictures before it, the oil filler cap is vented. The draft tube could be
removed with a PCV valve fitted to what would be the side plate on our
Zephyr motors etc.
Picture 4 this system is known as the
closed system because the oil filler cap is no longer vented, instead the
rocker cover is vented through the air cleaner.
Disclaimer:
The advice and guidelines given in these articles are given in good faith.
The owners and managers of the Galeforce Zephyr site will take no
responsibility for any injuries or loss sustained while carrying out the
described tasks and procedures or any consequences arising. Please read
the Safety First
Article