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SERIES 60 HEAT EXCHANGER (PLEASURE CRAFT MARINE)

The heat exchanger used on the Series 60 marine engine is a stacked plate cooler design assembly. In this type of assembly, heat exchanger membranes or plates are stacked side-by-side with special gaskets between the plates. The plates and gaskets are then compressed in a bundle to provide sealing. The sides of the heat exchanger plates are exposed for enhanced heat rejection and to make it easier to detect coolant leaks, which could lead to a low coolant level and engine overheating. The system operates as follows: ‪

Hot engine coolant from the thermostat housing flows into the heat exchanger tank and through the plate stack. See Figure 35404 . As this is taking place, sea water from the raw water pump flows into the charge air cooler and then into the plate stack. See Figure 35405 . Sea water flows through the plate stack on one side of the plates, while engine coolant flows through on the opposite side, reducing the temperature of the engine coolant inside. This lower temperature coolant then flows back to the fresh water pump and is disbursed again throughout the engine. ‪

Note: The heat exchanger tank is mounted onto six isolators to minimize the effects of normal engine vibration. These isolators must be replaced whenever the heat exchanger is removed.

Fresh Water Flow on Heat Exchanger-Cooled Pleasure Craft Marine Engine

Raw Water Flow on Heat Exchanger-Cooled Marine Engine

Repair or Replacement of the Heat Exchanger

To determine if repair is possible or replacement of the heat exchanger is necessary, perform the following procedure. See Figure 36012 . ‪

Flowchart for Repair or Replacement of Heat Exchanger

Removal of the Heat Exchanger

Remove the heat exchanger from the engine as follows: ‪

HOT COOLANT

To avoid scalding from the expulsion of hot coolant, never remove the cooling system pressure cap while the engine is at operating temperature. Wear adequate protective clothing (face shield, rubber gloves, apron, and boots). Remove the cap slowly to relieve pressure.

  1. With the engine at ambient temperature, place a suitable container beneath the heat exchanger. Open the fresh water drain cock and drain the engine coolant from the tank. Close the drain cock.

    Note: If the coolant is to be reused, cover the container and place in a protected area away from possible contaminants. If the coolant is not to be reused, dispose of it in an environmentally friendly manner according to state and/or federal (EPA) recommendations.

  2. Place a suitable container beneath the heat exchanger. Open the sea water drain cock and drain the raw water from the tank. Close the drain cock and discard the raw water.

    NOTICE:

    The heat exchanger is fastened to the mounting bracket with six (6) M8 mounting bolts, four on the bottom and two on the back. When removing the heat exchanger, do not remove any of the bolts on the heat exchanger itself. These bolts are used to hold the components of the heat exchanger assembly together. Removing them will result in loosening of the core membrane plates and coolant leakage,which could lead to overheating and severe engine damage. ‪

  3. Loosen the hose clamps holding the raw water inlet and outlet tubes to the heat exchanger. Slide the hoses along the tubes and disconnect the tubes from the tank.
  4. Loosen the hose clamps holding the engine coolant inlet and outlet tubes to the heat exchanger. Slide the hoses along the tubes and disconnect the tubes from the tank.
  5. Remove two (2) mounting bolts holding the heat exchanger to the back isolator brackets.
  6. Remove four (4) mounting bolts holding the heat exchanger to the isolators on the bottom bracket.
  7. Using a suitable chain hoist and sling, lift the heat exchanger from the engine.
Inspection of the Heat Exchanger

Inspect the heat exchanger assembly as follows: ‪

  1. With the engine at ambient temperature and cool to the touch, inspect ends of the heat exchanger plates for any signs of fresh water coolant or raw water coolant leaks. Leaks can be detected by feeling beneath the core or by visually checking the floor beneath the heat exchanger.
  2. Inspect raw water and fresh water coolant fittings on the back of the heat exchanger assembly. If fresh water or raw water is found leaking from the plate bundle, the heat exchanger must be disassembled, the plates and gaskets must be inspected for serviceability, and the heat exchanger must be reassembled with new gaskets or plates, as required.

Disassembly of the Heat Exchanger

Disassemble the heat exchanger assembly as follows: ‪

Note: It is not necessary to remove the heat exchanger assembly from the engine for disassembly and repair.

  1. With the engine at ambient temperature, place a suitable container beneath the heat exchanger. Open the fresh water drain cock and drain the engine coolant from the tank. Close the drain cock.

    Note: If the coolant is to be reused, cover the container and place in a protected area away from possible contaminants. If the coolant is not to be reused, dispose of it in an environmentally friendly manner according to state and/or federal (EPA) recommendations.

  2. Remove the M12 1.75 X 130 mm left-center and right-center bolts (bolt locations 9 and 10 see Figure 35492 ) from the front cover plate of the heat exchanger. Install M12 1.75 X 180 mm bolts and spacers in their place. Tighten bolts securely.

    Front Cover Plate Bolt Location and Torque Sequence

  3. Alternating from top to bottom, gradually loosen and then remove the M12 1.75 X 130 mm top and bottom bolts from the front cover plate. Do not remove the M12 1.75 X 180 mm left-center and right-center bolts just installed. As bolts are loosened, the plate bundle will expand forward.
  4. With the expanded plate bundle resting only on the center bolt/spacers, support the plate bundle by hand and carefully remove the center bolts until the bundle can be pulled away from the tank/back plate. Remove the raw water inlet and outlet fittings. See Figure 35494 .

    1. Bushing ‪

    5. Plates ‪

    2. Retaining Bolt ‪

    6. Sight Glass ‪

    3. Washer ‪

    7. Heat Exchanger Tank ‪

    4. Front Plate ‪

    8. Raw Water Inlet Fitting ‪

    9. Spacer ‪

    Location of Heat Exchanger Components

    PERSONAL INJURY

    To avoid injury from improper use of chemicals, follow the chemical manufacturer's usage, handling, and disposal instructions. Observe all manufacturer's cautions.

    PERSONAL INJURY

    To avoid injury when using chemical substances, it is essential to observe the manufacturer's instructions for use, safety, and waste disposal.

    PERSONAL INJURY

    To avoid injury when using caustic cleaning agents, follow the chemical manufacturers usage, disposal, and safety instructions.

    EYE INJURY

    To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.

  5. Using pure mineral spirits or a mild commercial cleaning solvent, remove any residual sealing material from the tank/back plate and from the cast front cover plate. Blow-dry with compressed air.
Inspection of the Heat Exchanger Components

Inspect the heat exchanger assembly components as follows: ‪

  1. Inspect cooling plates carefully for pinholes, splits, dents, or distortion. Replace any plate showing obvious signs of damage.
  2. Inspect gaskets on plates. Replace any gaskets showing signs of leakage, such as tears, cracks, or erosion.
  3. Inspect for buildups of deposits on plates and remove, if found.

    Note: There are small balls welded into the gasket groove of each plate and corresponding holes in the gaskets. Gaskets are easily replaced, since they simply snap into place on the plates. A "4corner" gasket is used on the sealing (first) plate and "standard" gaskets are used on the core plates and the closure (final) plate. Replacement plates and gaskets are available from authorized Detroit Diesel parts distributors.

  4. Inspect raw water inlet and outlet fittings for dents, distortion, or damaged sealing areas on the flanges, and replace if required.
  5. Inspect gasket contact surfaces on the tank/backplate for smoothness. If required, carefully smooth any rough areas that will come in contact with the gaskets on the plates.

Assembly of the Heat Exchanger

Assemble the heat exchanger assembly as follows: ‪

  1. Install two M12 1.75 X 180 mm long bolts, each with two spacers, into the center right and center left holes in the heat exchanger tank/backplate (locations 9 and 10 see Figure 35492 ). The spacers will properly align the plates during assembly.

    Heat Exchanger Bolt Hole Location

  2. Install raw water inlet and outlet fittings. Install the curved fitting (elbow) on the right side (as viewed from the rear of the heat exchanger tank), and angle it 3 degrees down from horizontal (pointing right).
  3. See Figure 36087 and install the first (sealing) plate, onto the center bolt/spacers. Install this plate with the gasketing side facing the tank and the letter "N" on the left-hand side as viewed from the rear of the heat exchanger tank.

    Gasket Faces and Orientation of Heat Exchanger Plates

  4. Install a core plate onto the center bolt/spacers with gasketing side against the smooth back of the sealing plate and the letter "N" on the right-hand side.
  5. Invert the next core plate and install with gasketing side against the smooth back of the previous core plate and the letter "N" on the left-hand side.
  6. Continue inverting and installing the remaining core plates, alernating the "N" locations right and left side until all core plates are installed.

    Note: Plates are correctly installed if the bent fins on the sides and ends touch each other, forming a honeycomb pattern, and not running parallel to each other. See Figure 35493 .

    Correct and Incorrect Pattern of Heat Exchanger Plate Assembly

  7. Install the closure plate (no openings) with gasketing against the smooth back of the last core plate.
  8. When all cooler plates are stacked, install the cast aluminum front cover plate.

    Note: The wider web sections of the front cover plate are positioned toward the top (tank) side. Secure with four (4) long M12 1.75 X 180 bolts, spacers, and washers in positions 2, 5, 6 and 1. See Figure 35494 .

  9. Position angled raw water outlet fitting three degrees below horizontal, facing outboard.
  10. Use M12 1.75 X 180 mm bolts and spacers at locations 2, 5, 6 and 1 for initial tightening. Alternating from side to side, tighten 180 mm long bolts uniformly and evenly until shorter M12 1.75 X 130 mm bolts will reach the threads. When plates are compressed to allow use of 130 mm bolts, install the shorter bolts with washers and spacers in positions 3, 7, 8, and 4. Snug bolts, but do not tighten.
  11. Remove 180 mm bolts from locations 2, 5, 6, and 1. Install 130 mm bolts with washers and spacers. See Figure 35492 . Snug bolts, but do not tighten.
  12. Remove 180 mm bolts and one spacer from the center hole locations 9 and 10 and replace with 130 mm long bolts, spacers, and bushings.
  13. See Figure 35492 for torque pattern and gradually snug up all bolts evenly so as not to warp or distort the plates. When bolts are bottomed against spacers, torque to 108 Nm (80 lbft) using the torque pattern shown.

Installation of the Heat Exchanger

Install the heat exchnager as follows: ‪

  1. If previously removed, install heat exchanger mounting bracket onto the gear case cover with four (4) M14 mounting bolts. Torque to 190 Nm (140 lbft). Install battery-charging alternator; refer to section .
  2. Six synthetic rubber vibration isolators are used with the heat exchanger mounting bolts. Each isolator is installed with four No. 10 24 X 0.5 in. L. slotted head screws. If previously removed, install four isolators onto the bracket base using four screws per isolator. Install the two remaining isolators onto the isolator mounting brackets attached to the gear case cover and the accessory drive cover plate.

    NOTICE:

    Before assembling the heat exchanger tank to the bottom support and engine fromt cover, make sure the isolators are positioned with their high sides against the tank. Failure to observe this precaution may result in component misalignment and greatly degraded isolator performance. ‪

  3. Using a suitable chain hoist and sling, carefully lower the heat exchanger onto the mounting bracket. Line up the holes in the isolators with the bolt holes in the bottom and back of the heat exchanger tank. Install six (6) M8 bolts through the isolators and torque to 35 Nm (26 lbft.).
  4. Using required blue connector hoses and hose clamps, attach the raw water inlet and outlet tubes to the heat exchanger tank. See Figure 36088 .

    Back of Heat Exchanger Showing Piping

  5. Using required blue connector hoses and hose clamps, attach the fresh water inlet and outlet tubes to the heat exchanger tank.
  6. Fill the fresh water cooling system with the required coolant.
  7. Prime the raw water pump, if required.

    PERSONAL INJURY

    Diesel engine exhaust and some of its constituents are known to the State of California to cause cancer, birth defects, and other reproductive harm.

    • Always start and operate an engine in a well ventilated area.
    • If operating an engine in an enclosed area, vent the exhaust to the outside.
    • Do not modify or tamper with the exhaust system or emission control system.
  8. Start the engine and check for leaks.