Volvo B21 engine - AbsoluteAstronomy.com

The Volvo B21 was a slant straight-4

Straight-4

The inline-four engine or straight-four engine is an internal combustion engine with all four cylinders mounted in a straight line, or plane along the crankcase. The single bank of cylinders may be oriented in either a vertical or an inclined plane with all the pistons driving a common crankshaft....

engine first used in the Volvo 200 series

Volvo 200 series

The Volvo 200 series is a range of large family cars , produced by Volvo from 1974 to 1993, with more than 2.8 million units sold worldwide. The 200 series was essentially an updated version of the 140; both were designed by Jan Wilsgaard. It shared the same body, but included a number of...

, meant to replace the B20. The B21 and all derived engines are often referred to as red block engines for the red paint applied to the block. The primary differences when compared to the B20 were the switch to a SOHC in place of the older pushrod configuration, and an aluminum crossflow cylinder head

Crossflow cylinder head

A crossflow cylinder head is a cylinder head that features the intake and exhaust ports on opposite sides. The gases can be thought to flow across the head...

versus the iron head of the B20.

History

Initially the overhead camshaft versions were offered as optional equipment on the 240, becoming standard in all markets by the 1976 model year. The overhead camshaft motors were available in displacements of 2.0 (B19 and B200), 2.1 (B21), and eventually 2.3 (B23 and B230) litres. The B21 featured an 80 mm (3.1 in) stroke, and 92 mm (3.6 in) bore. In the US, the B21's power output ranged anywhere between 98 hp and 107 hp (73 to 80 kW), based on variations in the compression ratio and was typically supplied with a B or M camshaft.

The engines are tilted approx 15 degrees to left (exhaust side) to make room for the more complicated injection systems. B19 and B21 blocks can be identified by water plugs on one side of the block. The B23 blocks have them on both sides. The camshaft is driven by a toothed belt that is driven off the front of the crankshaft. The belt turns the intermediate shaft as well, which in turn drives the oil pump, distributor (on 240 engines and BXX 700/900 series engines) and the fuel pump of carburetor models.

In 1981 the B21FT, a B21F with a turbo, was introduced with a compression ratio of 7.5:1 mated with a Garrett

Garrett AiResearch

Garrett AiResearch was a manufacturer of turboprop engines and turbochargers, and a pioneer in numerous aerospace technologies. It was previously known as Aircraft Tool and Supply Company, Garrett Supply Company, AiResearch Manufacturing Company, or simply AiResearch...

T3 turbocharger and a T camshaft. Additional turbo variants, not offered in the US market, were the B19ET and the B21ET, based on the B19E and B21E respectively. The turbocharger increased power output to 127 hp (91 kW) for the B21FT, and 157 hp (115 kW) for the B21ET. Also new for the 1981 model year was the B23, with a displacement of 2.3 litres (80 mm stroke and 96 mm (3.8 in) bore). Aside from the increased bore size, the engine is identical to the B21. Volvo used a slightly different mold for the turbo engines to cast a boss for the turbo oil return line. Because a turbocharged engine has a higher operating temperature

Operating temperature

An operating temperature is the temperature at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the...

they used sodium filled exhaust valves and a thermostat controlled oil cooler (air/oil model).

In 1983 the B23 was introduced to the American market. Also introduced in 1983, the "intercooler boost system" (IBS) was introduced for the B21FT motors. The IBS kit consisted of an intercooler, appropriate ducting, a new fan shroud, new oil cooler lines and mounting brackets, and optionally an automatic transmission kit. IBS raised the output of the B21FT to 162 hp, slightly more than the non intercooled European market B21ET's 157 hp.

Midway through the 1984 model year, the "intercooler boost system" became standard on American 240 Turbos. Additionally a bigger clutch and a stepped flywheel were included.

In 1985 a revised, "low friction" design was introduced, dubbed the B200 and B230 (depending on displacement). Several components had design changes, longer rods (152 mm c-c, 7 mm (0.275590551181102 in) longer), pistons with a lower compression height, lower friction bearings (smaller in size) ,a crankshaft with 8 counterweights (instead of 4 on the older Bxx engines) and a heavy harmonic balancer in the crank pulley. 1989 saw an upgrade to the crankshaft, with a relocated axial thrust bearing back to the number 5 journal, bigger main bearings, rods were enlarged to 13 mm (0.511811023622047 in) from 9 mm (0.354330708661417 in) in 1990. Also introduced in 1989 were 16 valve, twin-cam variants of the B200 and B230, dubbed the B204 and B234 respectively. The B204 was also available in turbo form in some markets (such as Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

) where large displacement motors were taxed heavily. It came in two versions: The B204GT turbo motor operates with a lead resistant lambda probe and generates approximately 200 hp. The B204FT has a catalytic converter

Catalytic converter

A catalytic converter is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint...

and generates 185 hp. Both were the first redblocks standard equipped with oil squirters for piston cooling. Crankshaft, conrods and pistons all forged. Exhaust valves were sodium filled for cooler operation. It has smaller valves and stiffer valve springs than n/a 16V. Crank torque is 290 newton metre at 2950 rpm for the GT, and 280 newton metre for the FT. Other differences from the normal 16V redblock engine are that it uses a remote mounted oil filter (Away from block on exhaust side engine mount) and a windage tray.

For the B230 engines 1993, piston cooling, oil squirting jets were added to help alleviate piston slap problems on the turbo motors. Another modification was to go from a square toothed timing belt setup to a round toothed timing belt setup which made for quieter belt running.

The last redblocks were made in 1998, when the 940 model was discontinued.

B17

Special version for certain European export markets (e.g. Greece, Israel) with shorter stroke than the B19, 88.9 by 71.85 mm (3.5 by 2.8 in) bore and stroke for 1,784 cc displacement.

B19 Turbo

The 1,986 cc 100 kW B19ET was sold in certain markets where engines of over 2 litre displacement were heavily taxed, such as Italy. The engine has the same stroke as all other redblocks, the smaller displacement is the result of a smaller bore (88.9 x 80.0 mm). It is a very robust engine with forged pistons (made by Kolbenschmidt). The B19 later turned into the B200 low friction engine.

B23 Turbo

The B23ET and B23FT motors were offered for two years only in the 1983 and 1984 Volvo 700 and 200 series

Volvo 200 series

. Both the B23ET and B23FT are somewhat unique in the 700 series as they are were only turbo motor offered in the 700 series with a block mounted distributor, forged pistons and a forged crankshaft. The B23ET was the only redblock known to be equipped with a small coolant passage version of the higher flowing 405 cylinder head, the FT had to make do with normal 398 head. As these motors predate the low-friction B200 and B230 turbos and are equipped with forged pistons and crank, they are often considered one of the most robust Volvo turbo motors.

16 Valve

Introduced in 1989 for the 740 GLE (and later used in the 940/960), The 16-Valve Redblock motors were offered in both a 2.0 litre Turbo and a 2.3 litre 154hp Naturally aspirated version. The head was designed for Volvo by Porsche

Porsche

Porsche Automobil Holding SE, usually shortened to Porsche SE a Societas Europaea or European Public Company, is a German based holding company with investments in the automotive industry....

. In addition to the 16 Valve head, these motors were equipped with twin counter rotating external balance shafts and the engine block itself differs from the 8V redblock. The block differed from the standard B230 in that the auxiliary shaft (used to drive the oil pump and distributor on models that had block mounted distributors) was replaced with an external oil pump. The 16-Valve head was itself a completely new design for Volvo: The head was of a multi-piece design featuring a separate cam carrier and lower section. The later "white block

Volvo Modular engine

The Volvo Modular engine is a family of straight-4, straight-5, and straight-6 automobile piston engine produced from the first year Volvo 960 appeared with the B6304F engine . It has an aluminium engine block and aluminium 4-valve DOHC cylinder heads and uses SFI fuel injection and has...

" motors can trace their head design back to the two-piece setup found in the B204 and B234. The 2.0 litre variant was available in turbocharged form in some markets (B204FT/GT). Unique to the B204 turbo was an exhaust gas pyrometer which was used to detect excessively high exhaust temperatures. When excessively high exhaust temperatures were detected, the fuel injection computer would richen the mixture. It has a forged crankshaft, cast pistons, and 13 mm (0.511811023622047 in) connecting rods.

Although a powerful engine for its' time, the 16 Valve engine can experience some problems that can be solved easily. One of the few problems is the oil pump gear. The oil pump gear itself can fail around the mounting flange, or, more often, the weak 8.8(grade 5) grade bolt holding the gear can break. It is strongly recommended to use a 10.9 (grade 8) grade bolt when replacing the oil pump gear. Another cause for timing belt failure is improperly adjusting the timing belt on engines with a manual tensioner (1989 to very early 1990 models only) or improperly adjusting the balance shaft belt. Because this is an interference engine, damage will occur if the timing belt fails. Another common occurrence is that the balance shaft's oil seals are prone to leak on older engines. New replacement sealings tend to start leaking again due to 'worn in irregularities' on the shaft itself. Many people have removed the balance shaft belt or the balance shaft assemblies altogether to prevent belt failure and/or leakage. The balance shafts are only there to lessen vibration for a smooth idle, and removing them will not harm the engine. Once all the common problems are solved, the 16 Valve engines are just as reliable as their SOHC counterparts.

The recommended timing belt interval for these engines is every 50,000 miles, or earlier if the engine is modified. It is also recommended to replace the crank and camshaft seals at every interval and to thoroughly inspect the tensioner and idler pulleys for wear.

Volvo Penta

Volvo Penta sold the OHC redblocks as marine engines as well, just like the older OHV engines. Depending on the model the displacement was 2127 (as B21), 2316 cc (same as B23/B230 automotive) or 2490 cc. The engines with 2490 cc displacement, identified as the Volvo Penta AQ151 (8 valve) and AQ171 (dohc 16 valve) models, got a forged crankshaft with a longer stroke (86 mm stroke) together with pistons with a 3 mm (0.118110236220472 in) lower compression height. The 2490 cc blocks still had B230 cast in the block. Penta used both the 8 valve and 16 valve cylinder heads. Both the 8V and 16V variants used the same engine block series, the 16V versions didn't use the different block like the automotive B2x4 with balance shafts.

Nomenclature

The B21, and related red block motors, were named using the following convention: B##X or B##VX. Where B stands for "bensin" (gasoline), ## stands for the displacement in decilitres, and X is an appropriate suffix. On the later low-friction motors, V denotes SOHC configuration (0) or DOHC configuration (4, for 4 valves per cylinder).

i.e. B230 (SOHC, 2.3 litres), B234 (2.3 litres, DOHC * 4 valves per cylinder * 4 cylinders = 16 valves)

The following suffixes were commonly used by Volvo:

A - single constant-pressure type carburetor
Carburetor
A carburetor , carburettor, or carburetter is a device that blends air and fuel for an internal combustion engine. It is sometimes shortened to carb in North America and the United Kingdom....

(such as the Pierburg 175 CDUS), typically with manual choke
B - high compression, with twin carburetor's, either twin zenith-strombergs or twin SU's.
E - high compression, no catalyst, mechanically fuel injected k-jetronic
BxxET - K-jetronic turbo
B2xxET - Motronic controlled electronic fuel injetion, turbo.
F - low compression (9.8:1 on B230F, 9.5:1 on B280F, 10.0:1 on B234F and 10.7:1 on B6304F), USA/Europe version (F for Federal) with catalytic converter. Europe/APAC version, fuel injected (usually LH Jetronic or Bendix Regina)
K - single jet type carburetor
Carburetor
A carburetor , carburettor, or carburetter is a device that blends air and fuel for an internal combustion engine. It is sometimes shortened to carb in North America and the United Kingdom....

(such as the Solex-Cisac
Solex
Solex was a French manufacturer of carburetors and the powered bicycle VéloSoleX.The Solex company was founded by Marcel Mennesson and Maurice Goudard to manufacture vehicle radiators...

carbs), typically with automatic choke
G - LH2.4 Jetronic but without cat. converter, CO adjustment on the AMM (similar to LH2.2 Jetronic). Some models without O2 sensor, others with O2 sensor which requires regular replacement at intervals due to lead fouling. For markets which unleaded fuel was rare in the early 90's, e.g. Eastern Europe
FB - low compression version of B230F (9.3:1) with the "531" cylinder head and VX3 camshaft, power output 11 kW and 2 newton metre more than B230F. LH2.4 Jetronic fuel injection, for European markets.
FD - essentially a B230F fitted with Exhaust Gas Recirculation (EGR) and Pulse air system for cleaner emissions
T - turbocharged, after E or F suffix (example: B21ET, B230FT)
FK - low pressure turbo, 1995 onward, not supplied in North America. Identical to the B230FT engine of that time but lowered boost level (4 PSI)
FT - LH-jetronic 2.2/2.4 Turbo
FTX - Higher power output B230FT (approx 190 hp)