Mercedes Garage
Mercedes AMG V8 Valve Seal & Coolant Repair
Precision valve-seal replacement and full coolant-system overhaul for Mercedes-AMG V8 engines — M156, M157, M159, M177, M178. Carried out in our Essex workshop using manufacturer-spec procedures.
15+ yrs
Mercedes specialists
1,800+
engines rebuilt
12 mo
unlimited-mileage warranty
What This Service Involves
We carry out a full, manufacturer-aligned repair of the valve-seal and coolant systems on your Mercedes-AMG V8 engine. The process includes:
- Valve-seal replacement – precise removal of valve gear, camshaft locking, and fitting of new seals using correct tooling.
- Coolant-system diagnostic & overhaul – full pressure test, replacement of worn seals, hoses, thermostat housings, and correct bleed procedure.
- Reassembly with new consumables – every job uses new aluminium torque-to-yield bolts and OE-spec anaerobic sealant where required (e.g. M157/M178 valve covers).
- Final validation – road test and thermal cycle check to confirm leak-free operation and correct coolant flow.
This is a workshop-based repair – your vehicle is collected, repaired, and returned with a 12-month unlimited-mileage warranty.
From £6,500
Fixed-price AMG V8 valve-seal and coolant repair, inclusive of parts, labour, and testing.
Inside our workshop
Mercedes AMG V8 Valve Seal & Coolant Repair
Applicable Models & Engine Families
Our AMG V8 valve-seal and coolant repair covers the following engine codes and the Mercedes-Benz models they power.
C-Class
C63 AMG (W204, W205)
E-Class
E63 AMG (W212, W213)
G-Class
GLC-Class
GLE-Class
GLS
S-Class
SL
SLS AMG
M-Class
R-Class
CLK
CLS
For a full list of engine codes and variants, see our M156, M157, M159, M177, and M178 engine-family pages.
Our AMG V8 Repair Process
- 01
Vehicle Arrival & Inspection
We collect your vehicle (nationwide recovery available) and perform a full visual and diagnostic assessment to confirm the scope.
- 02
Engine Bay Preparation
Remove airbox, ignition components, and valve covers. Lock the camshafts and remove the chain tensioner.
- 03
Valve-Seal Replacement
Using specialised tools, compress valve springs, remove old seals, install new OE-spec seals, and reassemble.
- 04
Coolant System Overhaul
Pressure test, replace all suspect seals, hoses, thermostat housings, and refill with correct coolant mix.
- 05
Reassembly & Torqueing
Fit new torque-to-yield bolts and sealant as required, reassemble all components to factory torque specs.
- 06
Testing & Road Trial
Run engine to temperature, perform a full cooling system bleed, and road-test to ensure leak-free operation.
Why Choose Mercedes Garage
- 12-month unlimited-mileage warranty on all AMG V8 repairs
- Nationwide recovery from £70 – we bring your vehicle to our Essex workshop
- 3–5 working day turnaround from arrival (subject to parts availability)
- Quote in under 30 minutes during working hours
- Established 2009 with a dedicated AMG specialist team
- Full manufacturer-spec tools & equipment – including camshaft locking kits and torque-angle wrenches
Recent AMG V8 Repairs
All images are representative of our workshop process. View our case studies →
How the Process Works
- 01
Recovery & Booking
Arrange collection or drop-off; we assess your AMG V8 engine.
- 02
Inspection & Quote
We confirm the exact repair needed and provide a fixed price.
- 03
Repair
Our specialists carry out the valve-seal and coolant repair.
- 04
Testing & Return
We road-test, validate, and return your vehicle with a warranty.
Related Services
Explore other specialist services we offer for Mercedes-Benz engines:
Frequently Asked Questions
How long does the AMG V8 valve-seal and coolant repair take?+
Typically 3–5 working days from the vehicle arriving at our workshop, depending on parts availability and the specific engine variant.
Do you remove the cylinder head for valve-seal replacement?+
For most AMG V8 engines (M156, M157, M159, M177, M178) we replace the valve seals with the cylinder head in place, using specialised tools. This reduces labour and avoids disturbing head gaskets.
What parts are replaced as part of the coolant system repair?+
We replace all degraded seals, hoses, the thermostat housing, and any leaking components. We also perform a full system flush and refill with Mercedes-spec coolant (MB 325.0/326.0).
Is the repair covered by a warranty?+
Yes – every repair comes with a 12-month unlimited-mileage warranty covering both parts and labour.
Do you offer recovery if my car is not drivable?+
Yes – we provide nationwide recovery from £70. Most vehicles are recovered within a few hours of booking.