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- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche 991.1 Turbo 3.8L (520 Bhp) 2014-16
- Porsche 991.1 Turbo S 3.8L (560 Bhp) 2014-16
- Porsche 991.1 GT3 3.8L (475 Bhp) 2014-16
- Porsche 991.1 GT3 RS 4.0L (500 Bhp) 2015-16
- Porsche Cayman GT4 3.8L 2015-16
Fits:
Porsche 991.1 Turbo / Turbo S 3.8L 2014>> Porsche 991.1 GT3 3.8L 2013>>
Porsche 991.1 GT3 RS 4.0L 2015>>
Porsche 991.2 Turbo / Turbo S 3.8L 2016 >>
Porsche 991.2 GT2 RS 3.8L 2017>>
Porsche 981 Boxster Spyder 3.8L 2016
Porsche 981 Cayman 981 GT4 3.8L 2015-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 1
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99110613802
The product you are viewing cross references to these numbers
- Porsche 997 MK1 GT3 / GT3 RS 2007-09
- Porsche 997 MKII GT3 / GT3 RS 2010-11
- Porsche 992.1 GT3 CUP 4.0L 2021-24
Water pump thermostat insert
This genuine Porsche thermostat insert fits within the water pump / cooling system housing and helps regulate coolant flow through the engine and radiator circuit.
Fits
- Porsche 997 GT3 3.8L 2009 - 2011 M97.77
- Porsche 997 GT3 RS 4.0L 2010 - 2011 M97.74
- Porsche 992.1 GT3 Cup 4.0L 2021–24
Diagram ref no 8
What This Product Does
As coolant temperature changes, the thermostat adjusts circulation within the cooling circuit. Its operation manages warm-up and the subsequent flow needed to control engine temperature. The insert works inside the associated housing; it is not a radiator or water pump.
Functions
- Adjusts coolant circulation in response to temperature.
- Manages cooling-circuit flow while the engine warms.
- Contributes to temperature control once the engine is warm.
Technical Details
- Genuine Porsche component: 9GT121113A.
- Internal diagram descriptions identify it as a thermostat insert and thermostat.
- The 997 assembly covers M97.77 applications for 2010–11 and the M97.74 GT3 RS 4.0 for 2011.
- The additional engine-water-circuit diagram covers the 2021 911 (992) GT3 Cup.
- Surrounding housings, sealing rings and O-rings have separate diagram entries.
Symptoms of Fault
- Abnormally high or inconsistent engine temperature.
- Cooling-system warnings, steam or coolant loss.
- Dampness or dried coolant deposits near housing joints.
- Gurgling associated with air or insufficient coolant.
These signs can also arise from other cooling components, so diagnosis should establish the cause before the insert is replaced.
Why Replacement Matters
Incorrect thermostat operation can disrupt temperature control. Renewing an insert with a confirmed fault addresses that component rather than masking a wider cooling-system problem. During the repair, examine the housing and its separate seals for deterioration, and establish which additional components the job requires.
FAQs
- Does the insert include its housing?
The supplied diagrams show distinct housing components alongside the thermostat. Do not assume those components are included. - Are sealing components identified separately?
Yes. O-rings and sealing rings appear as individual entries in the associated assemblies. - What information is needed to confirm suitability?
Use 9GT121113A together with the vehicle model, production year, engine identification and corresponding parts diagram. For the Cup application, confirm the motorsport vehicle specification.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
9GT121113A
The product you are viewing cross references to these numbers