Alfa Romeo1995–1998Technical specifications

155 2.5 Turbo: Technical specifications

Workshop data for the 2.5-litre diesel (engine code VM31B). Covers engine, fluids, brakes, service, torques and air conditioning: the figures to check before a job or a parts order.

Common faults & fixes

Summary

Match the engine code (VM31B) to the vehicle before ordering parts or applying these figures.

Vehicle specifications

Overview

Make: Alfa Romeo
Model: 155
Years: 1995–1998
Fuel: Diesel
Engine code: VM31B

Performance & efficiency

Power: 92 kW (125 hp)
Engine size: 2,499 cc
Cylinders: 4 · OHC

Fluids & capacities

Engine oil (with the filter): 6.3 litres

All 95 specifications below

Engine & identification

Vehicle identification

No. of cylinders Type	4/OHC
Capacity cc	2499

Injection system

Fuel/injection pump assembly Make	Bosch
Fuel/injection pump assembly Type	VEL 585
Fuel/injection pump assembly Part No.	0 460 404 997
Injector nozzle Make	Bosch
Nozzle and holder assembly Part No.	0 432 217 222

Injection sequence

The injection sequence for the Alfa Romeo 155 2.5 Turbo (1995–1998) is 1-3-4-2.

Injection sequence	1-3-4-2

Valve clearances

Valve clearances for the Alfa Romeo 155 2.5 Turbo (1995–1998) are 0,25-0,35 mm inlet and 0,25-0,35 mm exhaust, measured cold.

Valve clearance - INLET mm	0,25-0,35 cold
Valve clearance - EXHAUST mm	0,25-0,35 cold

Engine oil & fluids

Engine oil

The Alfa Romeo 155 2.5 Turbo (1995–1998) takes 6.3 litres of engine oil with the filter.

See the reference table for the complete engine oil entries and their conditions.

Manual gearbox

The manual gearbox has a listed capacity of 2.0 litres. The specified oil is SAE 75W-90.

Coolant

The listed total cooling-system capacity is 8.0 litres.

Grades, filling conditions and capacities

Lubricants and capacities — complete reference
Engine oil options
Ambient temperature range	All temperatures
Engine oil grade SAE	5W-40 Synthetic
Engine oil classification API/ACEA	CF/B3
Ambient temperature range	-15°C➞
Engine oil grade SAE	10W-40 Synthetic
Engine oil classification API/ACEA	CF/B3
Engine with filter(s) litres	6.3
Other lubricants and capacities
Manual transmission oil grade SAE	75W-90
Manual transmission litres	2.0
Cooling system - total capacity litres	8.0

Brakes & wear limits

Brake disc thickness

Brake discs on the Alfa Romeo 155 2.5 Turbo (1995–1998) are replaced at a minimum thickness of 20,2 mm (ventilated) front and 9,2 mm rear.

Minimum disc thickness for replacement - ventilated Front	20,2 mm
Minimum disc thickness for replacement Rear	9,2 mm

Brake disc and drum dimensions

Disc runout Front	0,15 mm
Disc runout Rear	0,15 mm
Minimum pad thickness Front	1,5 mm
Minimum pad thickness Rear	1,5 mm
Parking brake travel No. of notches	1-3

Service & electrical

Battery

The Alfa Romeo 155 2.5 Turbo (1995–1998) uses a 12 V, 90 Ah battery (reserve capacity 160 minutes).

Battery V/RC(Ah)	12/160 (90)

Glow plugs

Glow plugs for the Alfa Romeo 155 2.5 Turbo (1995–1998): Beru 657 MJ, Bosch 0 250 201 033, Champion CH163 and Lucas/CAV HDS348.

Glow plug nominal rating V/A	11/13
Glow plug activation time secs	10 Max
Glow plug - part no. Beru	657 MJ
Glow plug - part no. Bosch	0 250 201 033
Glow plug - part no. Champion	CH163
Glow plug - part no. Lucas/CAV	HDS348

Tuning and emissions

Crankshaft position (n = ATDC) °BTDC	—
Adjusting method Engine/Pump	Pointer/Dial gauge
Idle speed rpm	820-860
Oil temperature °C	80
Idle speed - for smoke test rpm	820-860
Governed speed range - for smoke test rpm	4550-4750
Maximum time at governed speed secs	1,0
Test mode A/B	B
Probe type 1/2	1
Conditioning Accelerations/rpm	2-3
Smoke opacity - EU limit m-1 (%)	3,00 (73)
Smoke opacity - homologation value m-1 (%)	0,88 (32)

Starting and charging

Starter motor Make	Bosch
Starter motor Type	0 001 218 125
Maximum cranking amps A	243-297
Alternator Make	Bosch
Alternator Type	0 123 345 004
Alternator output A/V/rpm	85/14/3000

Service checks and adjustments

Oil pressure bar/rpm	3,9-5,4/5000
Radiator cap bar	0,98-1,08
Thermostat opens °C	81-85
Drive belt size - alternator mm	9,5x838

Tightening torques

Cylinder head
Cylinder head instructions	—
View more information	—
Renew bolts	No
Other engine tightening torques
Main bearings Renew bolts/nuts	No
Main bearings Stage 1	23 Nm
Main bearings Stage 2	43-48 Nm
Big end bearings Renew bolts/nuts	No
Big end bearings Stage 1	40 Nm
Big end bearings Stage 2	79-84 Nm
Oil pump to cylinder block	25 Nm
Sump bolts	10 Nm
Sump drain bolt	78 Nm
Flywheel/driveplate	108 Nm
Clutch pressure plate	33-40 Nm
Crankshaft pulley/damper centre bolt	127 Nm/176 Nm
Inlet manifold to cylinder head	30 Nm
Exhaust manifold to cylinder head	30 Nm
Injector/clamp	24-29 Nm
Injector pipe unions	15-20 Nm
Fuel/injection pump sprocket/gear	88 Nm
Fuel/injection pump flange	30 Nm
Glow plugs	22-24 Nm
Chassis tightening torques
Rear hub	—
View more information	—
Steering track rod end	29-35 Nm
Brake disc to hub Front	12 Nm
Brake caliper to carrier Front	50 Nm
Brake caliper/carrier to hub Front	22 Nm
Brake disc to hub Rear	12 Nm
Brake caliper to carrier Rear	50 Nm
Brake caliper/carrier to hub Rear	22 Nm
ABS sensor Front	5 Nm
ABS sensor Rear	5 Nm
Road wheels	82±9 Nm Alu=93±10 Nm

Air conditioning

No. of AC service connectors	2
Air conditioning restrictor type	Expansion valve
Compressor clutch/magnetic coupling	Yes
Compressor variable displacement solenoid	No
Air conditioning refrigerant Type	R134a
Air conditioning refrigerant quantity grams	700
Air conditioning oil group	PAG
Air conditioning oil Type	SP20
Air conditioning oil quantity cm³	240
Air conditioning oil viscosity ISO	100

Frequently asked questions

What is the injection sequence of the Alfa Romeo 155 2.5 Turbo?

The injection sequence for the Alfa Romeo 155 2.5 Turbo (1995–1998) is 1-3-4-2.

What glow plugs does the Alfa Romeo 155 2.5 Turbo use?

Glow plugs for the Alfa Romeo 155 2.5 Turbo (1995–1998): Beru 657 MJ, Bosch 0 250 201 033, Champion CH163 and Lucas/CAV HDS348.

How much oil does the Alfa Romeo 155 2.5 Turbo take?

The Alfa Romeo 155 2.5 Turbo (1995–1998) takes 6.3 litres of engine oil with the filter. See the reference table for the complete engine oil entries and their conditions.

What are the valve clearances for the Alfa Romeo 155 2.5 Turbo?

Valve clearances for the Alfa Romeo 155 2.5 Turbo (1995–1998) are 0,25-0,35 mm inlet and 0,25-0,35 mm exhaust, measured cold.

What is the minimum brake disc thickness for the Alfa Romeo 155 2.5 Turbo?

Brake discs on the Alfa Romeo 155 2.5 Turbo (1995–1998) are replaced at a minimum thickness of 20,2 mm (ventilated) front and 9,2 mm rear.

What battery does the Alfa Romeo 155 2.5 Turbo use?

The Alfa Romeo 155 2.5 Turbo (1995–1998) uses a 12 V, 90 Ah battery (reserve capacity 160 minutes).