MERPOWER-“Come-Home” Screws

28 06 2008

Access The \

Remember, some marine transmissions have a come-home feature you can engage if the forward clutch fails. Check the operator’s manual to see if yours is so equipped.

The come-home screws are accessed from the rear of the transmission, as shown above. With the engine off, remove the access plugs and turn the inner screws as directed in your manual, until they bottom. Re-install the plugs.

Caution: With the come-home screws engaged, there is no neutral position or reverse gear. Until your tranny is repaired, the boat will be moving forward anytime the engine is running! (Excerpt from PRACTICAL BOAT MECHANICS, to be published this fall.)

(Some of this material excerpted from “PRACTICAL BOAT MECHANICS”, by Ben L. Evridge, to be published this fall.)

MERPOWER-Avoid Cooler Plugging

20 06 2008

Raw Water Impeller Fragments Recovered From An Oil Cooler

When the raw water pump fails, which is usually due to running dry, the impeller must be replaced. But wait! You must find and remove the pieces of the failed impeller that flowed down stream from the raw water pump. Until you retrieve these pieces, you can consider the water flow from the raw water pump to be plugged.

This plugging will cause overheating of the transmission, the engine and also the wet exhaust system hoses and related plumbing.

As the above photo shows, this transmission oil-cooler, the first heat exchanger in this system, was eighty percent plugged. Transmission overheating and failure was the result.

After clearing the blockage, the next step is to lubricate the new impeller with mild liquid soap before installation of the impeller. Finally, run the engine for a few minutes to wash the soap from the system.

Deere Fuel System I.D.-DE-10

18 06 2008

The DE-!0 Fuel System

To identify your Deere diesel fuel system, compare it with this photo and those below.

Deere Fuel System I.D.-VP-44

18 06 2008

The VP-44 Fuel System

This photo identifies the VP-44 fuel system used by some Deere engines.

Deere Fuel System I.D.-Common Rail

18 06 2008

Common Rail Fuel System

This photo will help you identify the Common Rail fuel system that feeds your Deere engine.

MERPOWER-Carry These On The Water!

13 06 2008

1. Conversion charts to switch measurement units for bolt-tightening torque and for any other application, such as temperature or pressure.

2. Ultra-gray silicone sealer is heat resistant and is especially useful because it sets up very firm. Good silicone sealants will replace many paper and fiber gaskets.

3. Rolls of gasket paper in various grades and thicknesses are essential for maintenance and repairs. In a pinch, just cut open a Cheerios box and cut the gasket’s shape from the paper, then put a light coat of silicone sealer on both sides and install.

4. In addition, any paper suitable for a gasket will also make a very good shim. Some shims must be made of metal, such as steel, stainless steel, aluminum, brass, or copper. Galvanized and stainless steel stove pipe and even soft drink cans are also commonly available and make good shims.

5. Marvel Mystery Oil is an “upper cylinder lube,” which means it is a good lubricant for valve guides and piston rings. It is available at most fuel docks and auto parts stores and can be added to both the engine lubricating oil and the fuel tank for use with either a gasoline or diesel engine.

6. It’s important to have both stainless steel and high-strength bolts and hardware on your boat.

7. If you don’t have mechanical gages installed on the engine, consider carrying pressure and temperature test kits. These kits are available from Snap-on Tools.

8. Carry high-quality black and red electrical tape for insulation purposes and for marking positive and negative electrical conductors.

9. Take assorted sizes of crimp-on electrical terminals and heat-shrink tubing. The latter is plastic tubing that shrinks around electrical wires when heated. Small electrical supply kits are available at auto parts stores, and offer a good assortment of terminals and heat-shrink tubing.

10. Aquarium-grade silicone sealant is handy to have for emergency repair of the boat’s drinking water plumbing. If it won’t harm fish, it won’t harm you either!

11. Thread locking compound (Loctite) keeps bolts and nuts from vibrating loose and is highly useful stuff to have around.

12. Spare engine-cooling system thermostats, and the gaskets for them, are important to have in case of overheating.

(Some of this material excerpted from “PRACTICAL BOAT MECHANICS”, by Ben L. Evridge, to be published this fall.)

MERPOWER-Emergency Frequency Meter

6 06 2008

An Emergency Frequency (Cycle) Meter Check

When the Frequency Meter on your gen-set goes out, or is in question, try this: Check the accuracy of the frequency meter with a 120-volt clock (with a second hand), and a good wristwatch.

1-Just plug the 120-volt clock into the circuit powered by the generator and coordinate its second hand with the seconds on your wrist-watch.

2-Next, watch for three minutes to see if the generator-powered second hand runs faster or slower than the second hand on your wrist-watch.

3-Adjust the generator engine-speed until the second hand of the 120-volt clock matches the one on your wrist-watch.

(Some of this material excerpted from PRACTICAL BOAT MECHANICS, Ben L. Evridge, to be published this fall)