Mazda FS engine
Content
The Mazda FS engine is a 16-valve Japanese head, comparable in quality to Italian units from Ferrari, Lamborghini and Ducati. A block of this configuration with a volume of 1,6 and 2,0 liters was installed on the Mazda 626, Mazda Capella, Mazda MPV, Mazda MX-6 and other models of the brand, produced from 1993 to 1998, until it was replaced by the FS- D.E.
During its use, the engine has established itself as a unit with a high service life and acceptable maintainability. Such features are due to a whole range of technical parameters of the module.
Characteristics of the internal combustion engine FS
Mid-size engine with cast iron block and 16-valve aluminum cylinder head. Structurally, the model is closer to type B engines and differs from analogues of the F series in a narrowed inter-cylinder space, a reduced diameter of the cylinders themselves and a bore of the crankshaft supports for main bearings.
| Parameter | Value |
|---|---|
| Max. Power | 135 l. from. |
| Max. Torque | 177 (18) / 4000 N×m (kg×m) at rpm |
| Recommended fuel octane | 92 and above |
| Consumption | Xnumx l / xnumx km |
| ICE category | 4-cylinder, 16-valve liquid-cooled DOHC gas distribution mechanism |
| Cylinder Ø | 83 mm |
| The mechanism for changing the volume of cylinders | No |
| Number of valves per cylinder | 2 for intake, 2 for exhaust |
| Start-stop system | No |
| Compression ratio | 9.1 |
| Piston stroke | 92 mm |
The engine has an EGR gas recirculation system and hydraulic lifters, which changed the shims in subsequent series. The engine number, as in the Mazda FS-ZE blocks, is stamped on the platform under the copper tube, near the box on the radiator side.
Features
The main distinguishing feature of the Mazda FS engines are cone-shaped guides adapted to Japanese yokes. Their specific configuration led to the introduction of other design solutions.
Camshafts
They have notches to designate intake (IN) and exhaust (EX) axles. They differ in the location of the pins for the pulleys, which determines the position of the crankshaft in terms of the gas distribution phase. The camshaft on the back of the cam has a narrowing. It is necessary for a balanced movement of the pusher around the axis, which is an important condition for uniform wear of the assembly.
Oil supply
All-metal pusher with a distribution washer mounted on top. The system is designed to lubricate the bearing surfaces through the camshaft itself. On the first yoke there is a channel with milling to expand the cavity, which ensures uninterrupted oil supply. The rest of the camshafts have a groove with a channel for oil flow to all sides of each yoke through special holes.
The advantage of this design in comparison with the feed through the bed lies in a more uniform lubrication of the bed due to the forced delivery of oil to the upper part of the block, on which the main load falls when the cams that press on the pusher are released. Thanks to this technology, the operational resource of the entire system is increased. In practice, the wear of the bed and camshafts is lower than on complexes with a different oil supply method.
Cam mount
It is carried out with the help of bolts, which, according to the developers, is cheaper and more reliable than fixing with studs.
Heads
The first connecting rod has a camshaft oil seal with a hole for draining excess / waste oil at the lower level, which eliminates leakage of lubricants. In addition, the Mazda FS internal combustion engine uses a more complex technique for fitting the valve cover without grooves on the sides of the engine case, and not through the surface where the crescent-shaped groove gasket is located, which is characteristic of the manufacturing technology of the bulk of Mazda engines.
Valve
The 6 mm intake valve stem is equipped with a 31,6 mm head, which is 4 mm wider than the diameter of the intake seat, and due to the height of the valve, the zone of effective fuel combustion is larger than in the bulk of European cars. Outlet: seat 25 mm, valve 28 mm. The node moves freely without "dead" zones. The center of the cam (axis) does not coincide with the axis of the pusher, which causes the engine to rotate naturally in the seat.
The complex of such solutions provides an impressive engine life, its smooth running under increased loads and overall power in comparison with other Mazda engine models.
Reliability
The service life of the FS engine declared by the manufacturer is 250-300 thousand km. With timely maintenance and the use of fuel and lubricants recommended by the developers, this figure reaches 400 thousand km without overhaul.
Weak spots
Most FS engine failures are due to failed EGR valves. This happens for a number of reasons:
- Use of poor quality oil. A symptom of this type of malfunction is valve coking.
- Operation on fuel with the wrong octane rating or without proper engine settings. The operation of the motor in such conditions provokes the formation of burnouts on the valve caps.
Floating engine speeds, sudden loss of power and detonation are symptoms that indicate problems with the unit. Further operation of the car in such conditions is fraught with jamming of the valves in the open position.
The thrust surfaces of the crankshaft are another weak point of the Mazda FS engine. They receive output from the oil seals due to the specifics of the placement of the cams: initially, the shaft hole system was thought out so that the injected oil fell on the top of the cam and then, during its movement, was distributed over the connecting rod, forming a uniform film. In practice, the oil supply groove is synchronized only with the first cylinder, where lubricant is supplied at the moment the valve springs are pressed through (at maximum return load). On the 4th cylinder, at the same time, lubricant is supplied from the back of the cam at the moment the spring is pressed. On cams other than the first and last cams, the system is set to inject oil before the cam advance or after the cam escape, which causes shaft-to-cam contact outside the oil injection timing.
Maintainability
As part of maintenance, they replace:
- Oils. The procedure is performed every 15 thousand kilometers. The engine circulates 2,7 liters of lubricant, but 3,5 liters is enough to renew it. For this purpose, multigrade oil with a viscosity of SAE 10W-30 is used, as well as its variations SJ, API-SG or SH. The oil is changed along with the filter.
- timing belt. It is recommended to produce every 100 thousand run.
- Candles. Standard ones are to be replaced every 30 thousand kilometers, and platinum ones - after 80 thousand kilometers. Champion RC10YC4, Beru 14FR -7 UX, Denso PKJ16CR8, Bosch FR7DCX and NGK PZFR6F are recommended for installation in the Mazda FS engine.
- Air filter. Perform every 20-40 thousand km.
- coolant. Must be done at least every 2 years. The capacity of the filling tank is 7,5 liters.
On the shaft between the second and third pushers, a hexagon is a competent and useful option that simplifies access to the cylinders when mounting and dismantling pulleys. The recesses of the rear side of the cam are asymmetric: on one side the cam is solid, and on the other side there is a recess, which is justified given the given center distances.
The seat of the pusher has good hardening, there is also a tide - a channel for supplying oil. Pushrod structure: 30 mm in diameter with a 20,7 mm adjusting washer, which in theory suggests the possibility of installing heads with a hydraulic compensator or other cam profile different from the mechanical model.
