Warranty - Gunson GASTESTER G4125 Manual

Ensure that the unit is being calibrated to the 2% CO condition, NOT at zero). Ensure that the
probe is in air, not in the exhaust pipe. If these checks do not resolve the problem, it is possible
that the instrument has "drifted" generally due to collector box contamination or damage due to
impact (the instrument is more susceptible to damage when warm and in use); the unit should be
returned to The Tool Connection for service.
Higher Engine Speeds:
• The Gastester is designed to work at engine tick-over speeds; however it will also give a
reliable reading at higher engine speeds. Violent full throttle action to high engine speeds
should be avoided while the probe is inserted in the exhaust pipe; the pulse pump diaphragm
can be damaged in extreme circumstances.
• To test mixture weakening at higher RPM, increase the engine speed in increments of
approximately 300 RPM to 400 RPM up to a maximum of 2500 RPM, observing the reading
between each adjustment. (Remember that the instrument may take 15 seconds to respond
to a particular adjustment.) The CO level should fall progressively and stay low during a
gradual increase in speed.
• The mixture enrichment for acceleration can be tested by rapid opening and immediate
release of the accelerator. Opening to half throttle should be sufficient. Within a few seconds
of this operation the Gastester CO indication should increase before returning to its previous
setting. The degree of increase will vary according to how this procedure is carried out and
also with the type of fuel system. A fixed choke carburettor with accelerator pump will usually
give a more pronounced increase than a variable choke carburettor or fuel injection system.
More information on Gunson web site:
Over the years hundreds of different types of carburettor have been designed and used and thus
it is not possible to give a definitive guide to carburettor adjustment. For this reason Gunson
strongly advise the use of vehicle manufacturer data and service instructions.
Gunson have put together general guidance notes on carburettor adjustments, including fixed
and variable jet carburettors, multiple carburettors and fuel injection available only for download
from: www.gunson.co.uk
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This warranty is in addition to the statutory rights of the purchaser.
The Tool Connection has made every effort to ensure that this product is of the highest quality
and value to the customer. However, The Tool Connection can accept no responsibility for
consequential damage howsoever caused arising from the use of this product.
All technical enquiries regarding this product should be made to:
The Tool Connection Technical Service Department: +44 (0) 1926 818181
Please note that The Tool Connection cannot provide technical information or advice or service
data on particular motor vehicles.
If this product should require service or repair, it should be returned to:
The Tool Connection
Kineton Road
Southam
Warwickshire
CV47 0DR
England
Please give full details of faults requiring attention when sending goods for service or
repair.

8. Warranty

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