Maintain maximum power
Page 59
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WHEN the Seddon Atkinson 200-Series was announced in late 1 975 one of the major points of interest concerning the specification was the choice of engine—the International Harvester D-358.
So numbered because of its cubic capacity358 cuin or 5.9 litres—the engine produces 100kW (134bhp) at 3,000rpm with a maximum torque figure of 355Nm (266Ibft) at 1,600rpm. Although this is a comparatively high maximum power speed, International has taken great pains to stress that the engine was designed originally to run at 3,000rpm—it is not a stretched and uprated engine.
Although the D-358 engine is of straightforward design, it is unfamiliar to UK operators so the following servicing tips should be useful to transport managers, drivers and workshop staff alike. • Many workshops faced with a mild engine overheating problem sometimes remove the thermostat as a temporary measure until the fault can be investigated fully. This must not be done with the 1H engine as it has a bypass cooling system and a vortex could be created in the coolant, making the situation worse.
• The compressor belt adjustment is not the link type arrangement usually found on diesel engines. The D-358 unit has a standard Bosch layout which features a split V-pulley. Belt adjustment is carried out by removing or adding shims between the two pulley halves thus effectively raising or lowering the depth of the vee. One important point to remember is that, if shims are removed from the middle of the pulley assembly, they should be fitted to the outside so they can be found easily when next required.
• If it is ever necessary to take off the timing case, take
5 note of the fact that there is a nut situated behind the water pump which must be removed and to do this, the water pump must come off first. As the timing case nearly comes without removing this nut, there is a temptation for -the fitter to assume that the case is merely sticking and give it a persuasive thump 6 with a mallet.
• The D-358 engine has the pressure relief valve situated in the oil filter assembly itself so while it is probably possible to find another type of filter which would fit, it would not incorporate the relief valve. Again this would probably be alright until a blockage occurred • A series of distance pieces is incorporated in the crankshaft pulley oil seals. This can be repositioned to allow the seal to be knocked in a little further so it isn't always running in the same groove.
• If the rocker cover has to come off, after the engine has been running, say for rocker adjustment, it is a good idea to wait a couple of minutes before removing it. This is because the slight inclination of the engine allows oil to be retained, so if it is essential to remove the cover immediately the engine has stopped, a couple of rags will come in handy to mop up any stray lubricant.
• A useful guide to getting the rocker shaft lined up correctly is provided at the end of the shaft in the form of a punch mark which should be lined up with the clamping slot (see diagram). This ensures that the oil part in the shaft lines up with the respective oil way in the bracket.
• If a major overhaul is ever necessary, the pistons come out from the top. Although it is possible to withdraw the piston/rod assembly from the bottom, this means taking the crankshaft out which should not really be necessary unless a regrind is envisaged. The crankshaft is induction hardened to a depth sufficient to allow 10, 20 and 30 thou regrinds. As it is induction hardened there . is no need to reharden after a regrind.
• The balance weights on the crankshaft are bolted on and if the crank is to be reground, these weights should be taken off. The whole assembly must be rebalanced after the regrind—it is not just a case of putting the same weights back on.
• When taking the injection pump off the engine, life is made a lot easier by using the special spanner available because the inner retaining nut is concealed between the block and the pump.
• Seddon Atkinson runs familiarisation courses for fitters on the International engine, For any operators interested in sending their workshop staff on such a course the person to contact is Mr G. Fishwick at Seddon Atkinson Vehicles Ltd, Club Street, Bamber Bridge, Preston PR5 6FN. •Graham Montgomerie