This page could be found on VCNA's website but suddenly disappeared. Since we think it contains some useful information we have put a copy of it here on our website. Volvo 164 Club of Sweden, January 15, 2001.

PARTS FAMILIARIZATION WORKBOOK NO. 2 240/260 Section 3: 1985 Through 1987 240/260 Models
INTRODUCTION Part - 1 Ongoing refinements to the 240 were made from 1985 through 1987. Although these models appear to be very similar to the 1978 through 1984 models, many subtle improvements were made. These improvements added more new part numbers to the range. The parts catalog system was growing becasue of this increase in the number of 240 parts. This Section is split up into the following segments: Engine/drive train Electrical/brakes Suspension/steering Body
Engine/Drive Train In 1985 the B-23OF was introduced as a replacement for the B-23F used on the 1984 non-Turbo U.S. models and the B-23E used on Canadian 240 models. It contains the same dependable overhead camshaft, aluminum cylinder head and cast iron block design of its predecessors. The B-23OF engine is used on the DL and GL models. The B-21F - Turbo engine was used in the Turbo models.
The B-23OF engine features lighter pistons, new piston rings, relocated and lighter piston pins, lighter forged connecting rods, and an alloy steel crankshaft with eight counterweights (previously four). Other improvements include smaller main and rod bearings to help reduce friction and a few other internal revisions. Why make internal changes to an already dependable, economical engine? The reasons speak for themselves: Internal friction was reduced by 15%. Vibration was reduced. Fuel consumption at idle was reduced by 4%. Cold starting was improved and overall engine operation was quieter and smoother. The fuel/emissions system (called LH-Jetronic 2.2) is an improvement over the previous system. A drawing of the component parts appears below: Notice that two parts, both called electronic control unit appear on the diagram. One works the ignition and is located in the engine compartment on the front right side. The other controls the fuel injection system and is located in the car interior.
	Many control units look alike. Do not assume that units can be interchanged between Volvos. For instance, an ignition control unit for a 1985 240 with a B-230F engine should not be replaced with a similar-looking control unit from a 1985 Volvo 740 that also has a B-230F. Always use the correct part number for a specific application.
The six-cylinder diesel engine (D-24) 240 sedan and wagon models were available in very limited numbers -all were late 1984 production, and none was available in California. Parts for these engines were discussed in the previous section.
The last year for the 240 Turbo was 1985. By that time, the B-21F - Turbo came with an air-to-air intercooler standard from the factory. An extra cooling fan is mounted in front of the radiator and intercooler to increase air flow. Various improvements to the component parts in the driveline (also called power transmission) continued to occur. None of these improvements changed the basic design of the driveline previously mentioned in Section 2. Changes include new parts like larger bearings in some transmissions, different splines on the propeller shaft and other detail improvements. Starting with the 1987 models, a new five-speed manual transmission (designated M47) was introduced. The M47 is a further development of earlier Volvo manual transmissions. The M45 is the original, basic 240 four-speed manual transmission. The M46 transmission is basically an M45 with an overdrive assembly added to it. Along this same line of thought, the M47 is an M45 with a fifth gear assembly added. Parts vary between transmission types, so never assume that an M45 or M46 part will fit an M47.