Stopping All Engines; Fuel System - Lehman SP90 Owner's Manual

Stopping all Engines

The engine should be allowed to slow idle for approximately 2 minutes before stopping, especially after extended
periods of full load and full speed operation. This is particularly important in the case of turbocharged engines.

Fuel System

CAUTION: Your injection pump is a very accurately machined piece of equipment and requires careful handling
and adjustment. No repairs other than shown herein should be entrusted to other than a diesel repair facility having
the required tools, knowledge and tesVcalibration equipment.
CAUTION: Never bend the injection pipes (which connect injection pump to injectors) as this may unbalance the
volume of fuel delivered to each cylinder.
CAUTION: Do not use a galvanized fuel tank as the zinc coating reacts with the fuel oil and forms undesirable
compounds which can foul the injection system.
The fuel injecton equipment is made to very accurate limits and therefore, even the smallest particle of dirt entering
the system will destroy its efficiency by causing blockage or scoring or premature wear on highly finished parts. A
clean fuel system is absolutely essential. Insure scrupulous cleanliness when handling fuel or fuel system compo-
nents. At all times make certain that water is not allowed to contaminate the fuel oil. Try to make a practice ofrefueling
out of the rain. Use a fine gauze filter funnel and always wipe the fuel tank around the filter cap before andafter
filling and immediately replace the cap.
An efficient, large size primary fuel filter and water separator (coalescer) is deemed a necessity in order to prevent
foreign particles reaching the injection equipment on your engine.
Your engine is equipped with secondary fuel filters which filter out contaminates that may find their way through
the primary filter. These filters (see Fig.
should be replaced once each season or at least each 200 hours (which ever comes first) under normal conditions.
(When replacing filters, use new gaskets or sealing rings to prevent air leaks.) Following filter replacement, blead
air from fuel system as later described under "bleeding the fuel system". Excess fuel delivered to the injectors by
the injection pump is collected by a tube located under the rocker arm cover (see A, Fig. 2) and delivered to fitting
C, Fig. 4 located at rear, right side of cylinder head. This fitting should be connected to top of fuel tank by
fuel line. It is recommended that the Boat Builders installs a short section of flexible tubing in this line to prevent
breakage due to engine vib
NOTE: All N/A Engines are fitted
with a common fuel return
line C D.
located towards rear of engine block, right side, have elements which
FIG. 3
TYPICAL FUEL SYSTEM, NATURALLY ASPIRATED ENGINES
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A Primary fuel filter water separator
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B Secondary fuel filter
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C Excess fuel return tube
-
D Injection pump return tube
(min.)