1997 MAZDA MX-5 engine

Fig. 12: Camshaft Bearing Cap Bolt Removal & Installation Sequence (Protege) Removal
Courtesy of MAZDA MOTORS CORP.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 19 © 2005 Mitchell Repair Information Company, LLC.

Fig. 13: Camshaft Bearing Cap Bolt Removal & Installation Sequence (Protege) Installation
Courtesy of MAZDA MOTORS CORP.
CRANKSHAFT REAR OIL SEAL
Removal & Installation
1. Disconnect negative battery cable. Remove transmission/transaxle and flywheel. For automatic
transmission removal procedure, see REMOVAL & INSTALLATION article in TRANSMISSION
SERVICING. For manual transmission removal procedure, see appropriate article in CLUTCHES. On all
models, pry out rear oil seal.
2. To install, apply light coat of oil to seal lip and push seal over crankshaft. Tap seal into rear cover until it
is flush with edge of rear cover. DO NOT bottom seal in cover.
3. Completely remove used sealant from flywheel bolts. Apply lock-type sealant to bolts and install
flywheel to crankshaft. Tighten bolts to 71-76 ft. lbs. (96-103 N.m) in a star-pattern sequence. Install
clutch assembly (if equipped) and tighten cover bolts to 13-20 ft. lbs. (18-26 N.m) in a star-pattern
sequence. Install transmission/transaxle. See appropriate article in TRANSMISSION SERVICING or
CLUTCHES.
WATER PUMP
Removal & Installation

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 20 © 2005 Mitchell Repair Information Company, LLC.

1. Drain engine coolant. Disconnect battery cable. Position No. 1 cylinder at TDC of compression stroke.
On Protege, remove right side cover and undercover.
2. On Miata, remove air cleaner intake duct from between throttle body and air cleaner/filter assembly. On
all models, remove upper radiator hose and by-pass hoses from thermostat housing.
3. Remove drive belts and water pump pulley. Remove power steering pump with hoses attached and secure
pump away from engine (if necessary). Remove timing belt, tensioner and idler. See TIMING BELT.
4. Unbolt water inlet pipe from water pump. Water pump inlet pipe has lower radiator hose and by-pass pipe
attached to it. Remove bolts from water pump. To install, reverse removal procedure. Tighten bolt to
specification. See TORQUE SPECIFICATIONS
.
OIL PAN
Removal & Installation (Miata)
1. Disconnect negative battery cable. Drain engine oil. Remove dipstick, tube and "O" ring. Raise vehicle on
hoist. Remove engine undercover. Disconnect steering column shaft at steering rack coupling. See Fig.
14 . Remove engine mount nuts. Lift and support engine using jack.
2. Support crossmember using transmission jack and remove crossmember bolts. Slowly and carefully lower
crossmember until clearance between oil pan and steering rack is about 4 inches. Remove oil pan bolts
from engine block and transmission.
3. DO NOT damage sealant contact surfaces. Remove oil pan by prying between oil pan and transmission
support. Remove oil pan baffle by prying it from engine. See Fig. 14
. DO NOT deform oil pan baffle.
Replace oil pan baffle if deformed. Clean sealant from oil pan, bolts, engine block and both sides of oil
pan baffle.
4. To install, apply oil resistant sealant to engine block and oil pan. Install oil pan baffle and oil pan within 5
minutes of applying sealant. To complete installation, reverse removal procedure. Tighten bolts to
specification. See TORQUE SPECIFICATIONS
. Fill engine with oil to specification. See ENGINE
LUBRICATION SYSTEM under ENGINE OILING. NOTE: For further information on cooling systems, see SPECIFICATIONS & ELECTRIC
COOLING FANS article in ENGINE COOLING.
NOTE: On Miata, engine must be supported in order to remove oil pan.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 21 © 2005 Mitchell Repair Information Company, LLC.

Fig. 14: Removing Crossmember & Oil Pan (Miata)

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 22 © 2005 Mitchell Repair Information Company, LLC.

Courtesy of MAZDA MOTORS CORP.
Removal & Installation (Protege)
1. Disconnect negative battery cable. Remove engine undercovers. Drain engine oil. Remove exhaust header
downpipe and brackets from front exhaust system. Remove oil pan retaining bolts.
2. DO NOT damage sealant contact surfaces. Remove oil pan by prying between oil pan and mounting
surface. On Protege, remove stiffener by prying between stiffener and cylinder block. On all models,
clean all sealant from oil pan, bolts, engine block and both sides of stiffener (Protege).
3. On Protege, apply oil resistant sealant to engine block and stiffener. Install stiffener. On all models, apply
sealant and install oil pan within 5 minutes of applying sealant. To complete installation, reverse removal
procedure. Tighten all bolts to specification. See TORQUE SPECIFICATIONS
. Fill engine with oil to
specification. See ENGINE LUBRICATION SYSTEM
under ENGINE OILING.
OVERHAUL
CYLINDER HEAD
Cylinder Head
Clean carbon and gasket material from all mating surfaces. Using a tap, clean cylinder head threads. Check
cylinder head warpage. If warpage exceeds specification, resurface head, but DO NOT exceed grinding limit.
See CYLINDER HEAD
under ENGINE SPECIFICATIONS. After resurfacing cylinder head, check cylinder
head height. Replace cylinder head if height is less than minimum specification.
Valve Springs
Ensure valve spring free length, out-of-square and compressed length are within specification. See VALVES &
VALVE SPRINGS under ENGINE SPECIFICATIONS. Replace valve spring if necessary.
Valve Stem Oil Seals
1. On Miata, use Installer Set (49-L012-0A0) to install valve seals. See Fig. 15 . Adjust installer dimension
"L" to seal depth of .720-.744" (18.3-18.9 mm). Using hand pressure ONLY, install seal until it contacts
cylinder head. Lightly oil valve seal lip.
2. On Protege, use Installer Set (49-L012-0A0) to install valve seals. See Fig. 15
. Adjust installer
dimension "L" to seal depth of .783" (19.9 mm). Using hand pressure, install seal until it contacts cylinder CAUTION: If reusing old oil pan bolts, remove old sealant from bolt threads.
Failure to remove old sealant may result in cracked block at bolt
holes.
NOTE: Intake and exhaust valve stem seals are different. Exhaust seals can be
identified by ridges molded into top of seal. Intake seals do not have identifying
ridges. Incorrect installation of valve stem seals will cause premature failure.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 23 © 2005 Mitchell Repair Information Company, LLC.

head. Lightly oil valve seal lip.
Fig. 15: Installing Valve Guide Seals

Courtesy of MAZDA MOTORS CORP.
Valve Guides
1. Check valve stem-to-valve guide oil clearance. Ensure valve guide inside diameter is within specification.
See CYLINDER HEAD
under ENGINE SPECIFICATIONS.
2. Completely disassemble cylinder head. Gradually heat cylinder head in water to 194°F (94°C). Using
Valve Guide Remover (49-B012-005), drive valve guide out, working from combustion chamber side of
cylinder head. Repeat procedure if required, keeping cylinder head hot so aluminum head will not warp.
3. If required, install new circlip on guide. Using proper components of Valve Guide Installer (49-L012-
0A0), adjust installer guide depth (dimension "L") to specification using depth micrometer or caliper. See
VALVE GUIDE INSTALLED HEIGHT
. See Fig. 16 .
4. Insert guide into pre-adjusted installer and drive guide into cylinder head from camshaft side until guide
circlip, and/or installer contact cylinder head. Measure dimension "L" (guide installed height). See Fig.
16 or Fig. 15 . If installed height is not within specification, adjust or replace valve guide or cylinder head
as necessary. See VALVE GUIDE INSTALLED HEIGHT
.
NOTE: On Miata, use only NEW exhaust valve guides to replace intake or exhaust valve
guides.

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 24 © 2005 Mitchell Repair Information Company, LLC.

VALVE GUIDE INSTALLED HEIGHT
Fig. 16: Adjusting Valve Guide Installer & Installing Guide

Courtesy of MAZDA MOTORS CORP.
ApplicationIn. (mm)
Miata & Protege.720-.744 (18.30-18.90)

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 25 © 2005 Mitchell Repair Information Company, LLC.

Fig. 17: Measuring Installed Valve & Guide Height
Courtesy of MAZDA MOTORS CORP.
Valve Seat
1. Service valve guide before valve seat. Valve seat replacement information is not available from
manufacturer. Inspect valve seat for roughness and damage. Check valve seat angle and seat width.
2. Measure seat contact width on valve and ensure seat contact position is in center of valve face. Service
seat if angle and width are not within specification. See CYLINDER HEAD
under ENGINE
SPECIFICATIONS. Measure valve installed height after servicing valve seat. See Fig. 17
. See VALVE
INSTALLED HEIGHT .
3. If valve installed height is within serviceable range, install adjusting shim on spring seat. If installed
height exceeds serviceable range, replace cylinder head.
VALVE INSTALLED HEIGHT
ApplicationIn. (mm)
Miata & Protege

1997 Mazda MX-5 Miata
1997-98 ENGINES 1.8L 4-Cylinder
Microsoft
Sunday, July 05, 2009 1:55:15 PMPage 26 © 2005 Mitchell Repair Information Company, LLC.