Determining The Condition of Your Engine (Part 1)

Topic: Boat Repowering (Part 1)

Question #1: How do I determine the condition of my Marine Engine so I can better understand how to approach my boat repowering needs?

Response: The quick and easy answer is to perform a compression test, however this is not always the best approach as it only paints a portion of the picture to the overall condition of the engine. With regards to determining the overall condition of the engine whether it applies to purchasing a boat or developing an approach to repowering the boat you already own we would divide the this into two separate categories; condition of the accessories and condition of the base engine itself. With regards to the condition of the accessories much of this is visual however determining the condition of the base engine you will need to perform a few tests.

Part 1 – Visual Inspection of the Engine Accessories
1. Is the engine operated in Salt Water? This may affect the condition of the electrical components that cannot be seen visually. However in general signs of corrosion can be seen on the metallic connectors.
2. Exhaust System – Remove the Exhaust Bellows to inspect the snout of the exhaust elbow/riser. Also check the sealing joints between the manifold and elbow for leakage. Select this LINK to read more about corrosion and view images.
3. Engine Circulating Water Pump – Inspect the underneath side just below where the large J hose conencts on the inlet side of the pump. This is where the weep hole is located that indicates pump seal failure.
4. Starter – Visually inspect the starter for signs of corrosion.
5. Alternator –  Visually inspect the alternator for signs of corrosion.
6. Engine Coupler – We strongly encourage changing the coupler along with all repowers since it requires the engine to be removed for accessibility when replacing. It isn’t worth re-installing an old coupler ontp a new enigne only to have have it fail after 20 hours of “Fresh Power”. Having to pull the engine again 20 hours later when the coupler could have been replaced much cheaper while the engine was already out of the boat.
7. SUMMARY – Evaluating the condition of the accessories is somewhat subjective however if the majority of the accessories appear to be in good condition, repowering with a new longblock could be a very good consideration.

Part 2 – Inspection of the Base Engine
READ MORE (select link)

Reference Articles
MARINE CORROSION
MARINE REPOWERING TERMINOLOGY

Tags: marine engines