Conclusion

Overheat Diagnosis

Leak checking the manifolds and risers is done in a similar fashion. Either, remove all the spark plugs from the side of the engine to be tested or loosen the manifold from the cylinder head and then flow water through the manifold with a freshwater hose as discussed earlier. If any water accumulates in the cylinder or runs down the exhaust passage inside the manifold, then there is a leak that needs to be fixed. Either the manifold is leaking at the gasket surface between the manifold and the riser or one of the two components is cracked. Repair or replace accordingly.

Conclusion

Hopefully this course has given you some useful tips to help diagnose engine overheats. Remember, these are guidelines and not all of these tests may be need to be performed. Always use logical and methodical diagnostic processes to determine the root cause of the overheat problem not just the damage done by the overheat. Each test result will dictate which and if any further tests are needed. Always follow Volvo Penta approved repair procedures.