Do You Need Your Head Examined? Maybe.Monday, November 1, 2010
It is not my forte, that is, Internal Combustion Engines, however, being around sweepers and scrubbers for 35 years, I have learned a little. Among many of the technical requests that I receive, many of them are “engine” related. Therefore, I find it fitting to have a topic about the engines, at least once in a while.
You wouldn’t think the IC (Internal Combustion) engine would work harder in the sweeper scrubber equipment than other equipment, industrial or construction. You may ask, “Why is that?” There are two reasons the IC engines have a harder life in sweeper scrubbers:
#1 First, sweepers do what they do. Sweeping dust and dirt over time is a killer.
#2 The engineering make-up of a sweeper scrubber mandates its wide variety of hydraulic pumps, valves and motors.
All of the hydraulic units are ran directly off the engine. Therefore, the engine must run at all times at full throttle or RPM. This is unlike the forklift that many hours can run at idle.
So, there are many engine-related questions that are asked of me. Which, again, leads me to the topic in the article, the cylinder head and head gasket. The question is, “Do I need a head gasket and how do I know if the cylinder head is cracked?”
The machine is a Tennant 6500 with a 1.3L Ford Engine. Let’s start with the most common symptoms of a bad head gasket.
#1 Blows white snow out of the exhaust
#2 Engine starts over heating
#3 Sometimes the motor oil becomes a white creamy liquid. This is a result of water getting into the oil.
#4 In rare occasions you will see water leaking from the head down the block.
Cylinder Head Removal
#1 Remove the air cleaner.
#2 Disconnect the spark plug leads, remove them from the clip on the rocker cover and position out of the way.
#3 Remove the rocker arm cover and gasket.
#4 Remove the rocker arm shaft bolts evenly and lift off the rocker arm shaft assembly.
#5 Lift the push rods from their locations and keep them in their correct order.
#6 Remove the spark plugs.
#7 Suitably support the appropriate valve with air pressure.
#8 Compress the valve spring, using service tool. Remove the valve spring retainer locks. Release the spring compressor, remove the valve spring retainer and the valve stem oil seal.
Cylinder Head Inspection
#1 Check the cylinder head for cracks and inspect the gasket surface for burrs and nicks. Replace the head if it is cracked.
#2 Many times cracks are so small they can not be seen by the naked eye. To be 100% certain, one should send the head to be magnafluxed by a certified engine re-builder.
Cylinder Head Installation
#1 Clean all gasket material from the mating surfaces and position the cylinder head gasket on the cylinder block using pilot studs.
#2 Position the cylinder head, remove pilot studs and install the cylinder head bolts.
Step One: Tighten the bolts down evenly in sequence.
Step Two: Tighten, in sequence at 22 ft-lb.
Step Three: Tighten, in sequence, 90°.
Step Four: (Final) tighten, in sequence, once again, 90°.
As always, if you have any questions or comments you can e-mail me at: firstname.lastname@example.org.