In the preceding articles we discussed some of the various aspects of doing a comprehensive tune up. Hopefully some light was shed on why we do or don't do certain things pertaining to inspections and order of events when doing a tune up. Perhaps some useful reasons were given for why parts fail and what to do about preventing part failure in the future. All these tips will help us think and reason out a problem in order to make our tune up last and, hopefully, keep us from spending extra money.

If the reader has been present from the beginning of this series he will recall making an inventory list before the tune up procedures began. On this list was a collection of observations of the overall engine and tractor condition. Some of the items on that list include the fluid levels and their color. As we continue our tune up discussion we will continue to examine some of the notes that were made.

The oil color can help you determine whether or not it is time for a change. On a gasoline engine, oil that is black as pitch is way beyond the change interval. Indications are that it is full of dissolved carbon and dirt. On the other hand, a diesel will usually have a black color to it as it is a reaction of the oil compounds and additives to the blow by of the piston which contains diesel fuel, sulphur, and emissions. A heavy brownish color of the oil along with tarnish on the dipstick usually indicates that the motor has been hot. The hot conditions have forced certain compounds of the oil to chemically react and produce the varnish looking appearance. A milky white color indicates excessive moisture in the engine. This can either result from a coolant leak into the oil or can be attributed to frequent on/off operation in colder or humid climates without letting the engine come up to a normal operating temperature for an extended period of time. Of course green droplets on the dipstick that smell sweet indicate antifreeze contamination in the crankcase. Oil that is an amber or lightish brown is the norm and should be changed along the recommended hourly or monthly guidelines supplied in your manual

A good tune up should include a fresh change of oil and filter. The oil is the blood of the motor. Microscopic oil films keeps moving metal parts from welding to each other. Keeping this lubricant clean and of a good quality will keep an engine running for many hours. There are many types of motor oils on the market today. Two basic catagories are the 'Texas' crudes and the 'Pennsylvania' crudes, each of which has their champions. Generally, the Texas crudes are pumped from deeper oil reservoirs and tend to have a higher parafinnic content than the Pennsylvania crudes. Since the oils have to meet a standard for parafin content it probably doesn't matter which geographic location it comes from. Oil viscosity is how fast the oil pours under given conditions. The lower the vis number the faster it flows. A 10 weight motor oil pours like milk at room temperature while a 40 weight pours like syrup. Lighter weights should be used under cold climate conditions where the motor will take a long time to come up to operating temperature; the lighter oil will lubricate better when cold. A heavier weight is best under hot climate or above normal engine running conditions as it won't run off of the motor parts as fast as a lighter oil. That is where multiviscosity oil, such as 10w-30, comes in. It has the characteristics of 10w oil when the engine first starts and the characteristics of 30w after operating temperature is reached. Some manufacturers recommend only a straight weight for their particular motor, so check your specs before you buy your oil.

Another motor oil rating is the American Petroleum Institute or API rating. This rating, SA, SB, SC, or CA, CB, CC pertains to the application of the oil. The 'S' related numbers are referring to automobile useage, the 'C' rating is dealing with trucks, industrial, and diesel engine applications. The 'A' subheading refers to a light load application up to the 'C' subheading which is a more severe operation of the motor. The same applies for the 'C' main headings. Overall differences in the numbers pertain to the additives present in the oil which retard corrosion, sulphur content (as in diesels), particle suspension chemicals, moisture absorbability, oil shear, and the like. Check with your manual to determine the appropriate application for your engine. Some oils have a high detergent heading on their containers. Keep in mind that these oils have a high internal engine cleaning ability and may not be the best thing to put into an older, unrebuilt engine. These detergents can loosen up built up carbon, goo, and debris in an older unit that may cause more serious problems such as the plugging up of the oil intake screen or circulation galleys and filters. Non detergent oils are available and should be considered on older motors that have heavy deposit build ups under the valve covers or oil filler cap.

Bring the tractor up to operating temperature, shut it off, and drain the oil into a pan. If the tractor has a high oil pan you can put a wide mouth funnel into an old milk jug and drain it directly into your disposal container. Make sure that the jug is big enough to take all the crankcase has to offer, though. When the oil is drained clean the plug threads with a clean rag and reinstall the plug, then move your container underneath the oil filter. Remove it, place it upside down in your container or funnel and let the oil drain out. Wipe off any accumulated dirt around the seal where filter mates to the engine. If the filter is easy to get to and can be reinstalled without tipping, fill it with clean motor oil before replacing it. Remove the engine breather cap or oil filler cap and inspect its underside. It should be generally clean of carbon, dirt, and goo. Heavy buildup or concentrations of the above may indicate further ventilation problems in the motor vapor circuit. Check the PCV (positive crankcase ventilation) valve and make sure it freely rattles and does not bind from excessive moisture/oil buildup. You also might check any vacuum hoses to the carburator base making sure they are not collapsed or have pin holes in them. Clean the oil cap and PCV valve with clean solvent, blow dry and reinstall. Fill the motor with the correct type and amount of oil. Do not overfill as the extra oil may cavitate in crankcase as the crankshaft counterweights come around. It will also promote seal and gasket failure by submerging those items in a constant bath of oil. One last note is to take the oil and filter to a recycling center for proper disposal. Consider that the oil itself never wears out, it merely gets dirty and the additives wear out. By re-refining it the oil will be identical to the stuff that comes out of the ground and goes through the same refining process.

After the oil and oil filter are replaced take a moment to inspect the air cleaner or oil bath unit. This often overlooked step may, literally, breath new life into your engine. If the filters have excessive dirt and debris in them it will reduce the efficiency of your engine by enriching the fuel to the combustion chamber. This will result in poor performance, black exhaust, excessive carbon buildup, washing of the cylinder walls from too much fuel, and internal engine wear. If the unit has a paper filter, remove it and inspect it for squashing or torn paper in the element itself along with any evidence of oil. If sound, reverse blow it (from inside to out) with an air gun taking care not to get too close to the paper itself with the air stream. Clean out the filter cannister, check the cannister to carburator gasket, and reinstall with the correct torque on the wingnut or retaining fastener. Oil in the filter element can indicate a faulty ventilation system or excessive blow by of the pistons from worn or broken rings. If the tractor has an oil bath cleaner assembly then remove the unit and disassemble on a work bench. Lift out the wire mesh and clean it in mineral spirits or equivalent solvent and let it air dry. Dispose of the oil in the lower body assembly, clean out the cannister bottom, and refill with fresh oil to the fill line. Check the tube that the air flows through to the engine (if so equiped) for dirt build up and debris. Also check the oil bath air cap assembly (if so equiped) for weed seeds and dirt. This unit is designed to make the incoming air create a vortex which moves much of the heavier material to the outside of the breather cap through centifugal force. The heavier debris then settles along the outside rim of the cap or dust collector instead of going into the oil bath itself. Before closing the cowl on the air breather service, check any intake air hoses between the engine and filter for cracking, drying out, oil contamination, or pin holes. In a dusty field even the smallest hole can let in damaging dirt.

Our engine should now have clean air and oil to extend it's life span and give it the ability to perform at its peak. Our topic next time will cover the cooling and fuel system along with miscellaneous tips on diagnosing engine maladies.

by Curtis Von Fange

Our tractor is coming right along. The old oil and filter has been taken to the recycler and the air filter replacement has breathed new life into our motor. Let's take a closer look, now, at the cooling system since it has to work so hard in the summer heat.

Cooling systems can be real cantankerous in their old age. Radiator cores clog up with rust, lime or other mineral deposits and the fins clog up with weed seeds and debris. The metal headers slowly corrode away from years of use and the seams seem to always be moist with residual antifreeze. On hot days the radiator cap bellows out a stream of steam and reminds one of an old model T along side the road with an overheated engine. So how can we recognize potential problems and catch them before they happen?

The radiator, usually at the front of the tractor, is a good place to start. Check the front and rear for a build up of bugs, seeds, and weeds from the pasture. Water from a garden hose sprayed from the fan side of the radiator will remove a lot of the built up debris. Next check for moisture around the radiator core and headers. If there is leakage it will be moist and smell sweet. If ther is leakage it would be wise to have the radiator professionally flow tested and checked for lime buildup and core leakage. Next, remove the radiator cap and inspect its bottom. The cap is designed to raise the pressure in the cooling system so the coolant boils at a higher temperature. Each pound of pressure raises the boiling point by 3 degrees. A six pound pressure cap would raise the boiling point of the coolant by eighteen degrees, or from 212 degrees to 230 degrees. Make sure and check the manual for the proper pressure cap as one that is too high has a tendency to blow hoses and radiator cores. The bottom of the cap should be clean and must fit snugly onto the filler neck. Check the rubber bottom for swelling, nicks, or cracks. Also check the brass filler neck for uniformity on the sealing surfaces. A warp or hairline crack will cause pressure to leak out when in use.

Before continuing with our antifreeze inspection it is wise to check all the cooling system hoses. Hoses that are hard, brittle or cracked need to be replaced. On other hoses look for small patches of moisture on the hose surface and then gently knead that area and hunt for a hairline crack or pinhole. These areas tend to leak only when the tractor is at operating temperature and under pressure and can be difficult to notice. When leaking, though, they can shoot a hair-sized stream of hot antifreeze onto electrical parts and cause engine misfiring. Look for hoses that have swelled up because of oil contamination. They feel greasy and spongy when kneaded. Replace any hoses that are marginal. It's good to change the hose clamps also as dirt and grit can make them hard to properly torque. Also make sure and purchase the correct hose size. A hose that is too big or too small will only cause problems at a later date, especially if a sealing compound like silicone is used to try to water tighten a connection.

Antifreeze, nowadays, is a mixture of ethylene glycol and water. It used to be a mix of ethyl or methyl alcohol and water. With technological advances and different sealing compounds along with higher engine temperatures the alcohol mix became antiquated as it would evaporate or not provide adequate internal part protection in regular use. Pure ethylene glycol works as a catalyst when mixed with water. In its pure state it freezes around nine below zero but when mixed in proper proportions with water it will provide protection up to 50 or so below zero. In addition to freezing protection the solution provides a chemical soup of internal engine protectors. It contains a rust retardant, particle suspension compounds, a lubricant for the water pump seals and bushings, and corrosion resistors. When these chemical compounds wear out the antifreeze will change color and/or get cloudy. A rusty antifreeze color, for example, means that the rust inhibitor has lived its useful life. Examine the color of the antifreeze compound in the unit you are inspecting. It needs to be a clean and green. Take a temperature tester and see what the freezing point is. If the antifreeze has been in the unit for more than three years it is a good idea to replace it. Changing the stuff isn't that big a deal. Drain the radiator contents into a container. Make sure not to spill any because the dog will love the sweet taste but it is highly toxic if ingested. Also find the drain cock on the side of the engine and drain the extra few quarts out of the block. Re tighten the block drain and refill the radiator with fresh antifreeze and, preferably, distilled water (this will reduce mineral buildup over time since it is relatively mineral free).

If working on a budget, like most of us do-it-yourselfers do, you might consider filtering out your old antifreeze. I made a filter out of some gravel, coarse sand, filter paper and cotton. It took a while for the solution to filter but when it came out the other end it looked great. But don't stop with just the filtered antifreeze. Get some litmus paper to see what the acidic content is and then get some antifreeze suplement at the auto store. This stuff has the additives in a mix that can be added to the old filtered antifreeze that will give it some additional lifespan. Like I said, it is a budget measure.

Time to check the belts on the engine. Most tractors will only have one, at most two belts. They usually run the fan/water pump assembly and generator. Grasp each drive belt and roll it around so that the bottom and one side are clearly visible. Look for signs of cracking, oil soaking, hard glazed contact surface, splitting or fraying. Replace any belt showing these signs. Make sure when installing new belts or when retightening old ones to get the correct belt tension. A belt too tight will cause premature wear on the bearings; a belt too loose will squeal, flap, and cause other unit problems.

One last tidbit to check on this section is the fuel filter. This often neglected item can cause no end to an engine running funny. When plugged it will lean out the fuel mixture and cause backfiring, spitting, and misfiring. When the engine dies back pressure from expanding vapor from the fuel pump will push debris from the filter back into the tank and let fuel flow freely....for a little bit. The engine will start up and run like normal until debris, once again, finds its way back into the filter element. If suspect, replace. It is a very low cost item. Also check the fuel hoses, if rubber, for kinking, pinching from tight bends, or internal swelling due to using a hose that is non compatible with gasoline. Also check to see if a fuel line is running near an exhaust manifold or pipe. The extra heat will sometimes cause a vaporizing problem on hot days where the fuel will turn to a gas in the line and cause the fuel circuit to 'vapor lock', or stop delivering fuel to the carb. If this happens a wrapping of aluminum foil around the fuel line and attached with bread twisties will reflect the radiated heat and help alleviate the problem.

by Curtis Von Fange

Buried somewhere beneath the sheetmetal, under the gas tank, or stuffed in front of the radiator is the battery. This elusive and neglected component of the tractor is the hardest to get to when it is dead and in need of a jump. But usually, the storage battery is a storehouse of electrical energy waiting to be released a the flick of a switch. A few maintenance tips and periodic cleaning will keep it charged for the duration of its life span.

The battery is made up of a number of lead based plates submersed in a solution of suphuric acid. One set of plates, the positive ones, comprised of lead peroxide, are separated by an insulating material from the second set of plates made up of sponge lead. Each of the separate plate sections are connected together by a positive or a negative lead lug. This insulated and autonomous unit is called a cell. When submerged in battery acid, a mixture of about 38 percent sulphuric acid and distilled water, it creates a potential of approximately 2.1 volts across the cell. The voltage is pretty uniform regardless of the number of plates used as it is a result of a chemical reaction, not a result of plate volume. But, the more plates that are found in each individual cell, the more amperage capacity the battery will have. Three of these cells combined together in series create a six volt battery, six connected together make a twelve volt battery. The hard black plastic case provides the inert mounting skeleton for the individual cells and gives a solution tight container for the acid. The battery terminals protruding from the case are for the respective positive and negative sections of the cells. Note that the positive battery terminal is always larger than the negative terminal.

Even though the battery appears tough and rugged it is important not to wrestle and jostle it around. As a battery ages sediments from the charging and discharging cycle collect in the plastic grid at the bottom of the cells. Shaking or rough handling of an older battery can loosen some of this material and cause it to lodge between the positive and negative plates. This can short out a cell and ruin the battery. When viewing down the cell filler plugs a cloudy appearance of the acid solution can indicate a shorted cell.

As mentioned earlier, the amount of lead plates in each cells determines the amperage capacity of that cell. Therefore, a high amp battery will have a larger number of lead plates in the cell than a lower capacity battery. Sometimes, though, this extra number of plates has to be installed in a battery case of the same size as a lower capacity battery. In order to do this the battery company makes the thickness’ of the lead plates thinner so as to fit more plates in the same area. There is only so much capacity that can fit into a given space. That is why tractors or trucks with large engines that require large electrical capacity to start have two or more large batteries. The extra plates needed to create the necessary capacity and give adequate battery life before the plates disintegrate from the chemical reaction require the added size. Take care in moving around the higher capacity batteries because the cell structure with added plates tend to make them a little more fragile.

Many tractor and truck batteries have the filler plugs or ports in them as previously mentioned. These ports have a dual purpose. When a battery discharges and recharges the chemical reaction process produces hydrogen as a by-product. The filler caps provide venting for this highly explosive gas to the atmosphere. When working with a battery always make sure any electrical load is turned off before removing the battery terminals. When charging a battery take care to unplug the charger when connecting or disconnecting the charging clips to the battery terminals. Even the smallest of sparks can ignite the escaping hydrogen and cause the battery to explode. When jumpstarting the battery, instead of clipping the negative clamp to the battery terminal, clip it to a grounded bolt or engine component away from the battery location. The corresponding spark from the charging vehicle will be controlled and isolated away from the battery, thereby avoiding a potential explosion. The second use for the ports is so one can replenish the water supply in the battery. Make sure and use only distilled water. Regular water from the tap can have impurities in it that will shorten the cell lifespan. Dissolved lime, for instance, can neutralize the suphuric acid if used in sufficient quantities. Other impurities can coat the lead plates with a microscopic film and reduce the effectiveness of the electrical reaction. Make sure and not overfill the cell; fill it to the base of the plug hole, and try to fill the cells while they are in the charging mode.

Now that we have a basic understanding of the battery lets discuss in further detail about its maintenance. An often neglected component of a battery is its holddown straps. An unsecured battery is an accident waiting to happen. The bouncing of a vehicle, especially a tractor over a plowed field, can cause a battery to scoot around in its housing and possibly short out against another metal component causing a fire. If not that, it can certainly break a terminal, cable, or case. Purchase a battery hold down kit and install it. It is cheap insurance against tractor damage and will increase the life span of the battery. Another great investment is a battery terminal remover tool. This cool tool looks like a small gear puller with clamps. After the terminal bolt is loosened, the puller makes removal of the terminal an easy job. Don’t screw a stuck terminal back and forth or use a screwdriver to try and pry it off. You can inadvertently crack the battery case or break the seal between the case and the protruding terminal. A puller is cheap, easy to use, and does the job correctly. Once the terminal end is removed, inspect the mating ends for corrosion, pits or cracks. A battery terminal cleaner works great for removing corrosion build up. This tool has two wire brush ends; one male, the other female. Use it to brush the ends until they shine. Sometimes a terminal end will have a hard blackish coating on it. This lead oxidation stops the electricity from flowing and creates excessive heat at the connection. It won’t always come off with the wire brush so you may have to use a small file. Make sure to rotate the file around the terminal as you go so you won’t create a lot of flat spots. Don’t remove too much material, then tidy up the terminal with the brush. If the bolt is corroded, replace with a new one. Excessive corrosion on the cable terminal can be removed by submersing the end in a coffee can of water and baking soda solution for a while. Remove, dry and then wire brush the mating parts. Terminal ends that are pitted, cracked, or missing due to acid corrosion, should be replaced. It is best, in the long run, to replace the entire cable rather than merely an end. If the terminal end needs replacing, the chances are good that the reason for damage has made its way up the cable under the insulation where it can’t be seen. Examples could be unseen corrosion damage, copper strands that have been too hot from resistance and have burned themselves into the insulation, or have been heat damaged, or have internal strand breakage.

After removing the hold down strap and terminal ends, remove the battery from the tractor and place on a plastic box or covering. Hose down the top of the battery and brush off the accumulated debris. Take a towel and dry off the entire casing. Remove the filler ports and check the levels. Place on charger and fill accordingly. One way to test the integrity of the battery is to check the specific gravity of each cell. A hydrometer, available at local auto stores, will measure the electrolyte acid content. It is best to read the directions that come with the tester thoroughly as variations due to temperature and states of charge can make the readings hard to interpret accurately. An easier method to determine battery integrity is to do a load test. With the battery installed in the vehicle, attach a voltmeter to the battery terminals. Ground the coil to keep the engine from starting and crank the motor over for 15 seconds. If the battery voltage stays above 9.6 volts, then the battery is in a reasonable state of charge. Below that amount indicates a shorted cell or a lowered capacity due to the battery reaching its useful life.

When reinstalling a used or new battery, use a terminal conditioner on the cable and terminal ends. The conditioner comes in a spray can and goes on like a red paint. The coating retards battery acid corrosion and lead oxidation and will lengthen the time between cleanings. One can also install felt pads onto the battery posts which have been saturated with baking soda. These also tend to retard acid corrosion. The negative cable has the smaller end and goes to the corresponding terminal. Don’t drive the terminal ends onto the posts using a hammer. The jarring action may damage the internal connections of the battery. Instead, use a terminal spreader. Don’t overtighten the terminal bolts as you can cause stress cracks on the ends. Reinstall the hold down brackets or straps making sure not to overtighten which can cause warpage and/or breakage of the battery case.

If a battery is to be removed for the winter months, take a few moments to ensure that it will be in good condition when spring comes. Clean the casing and dry with a towel. Clean the terminal posts and check the electrolyte level. Place the battery off of the floor, preferably on a wooden bench or shelf. Batteries left on concrete floors will lose their charge in a few short weeks. Place a trickle charger on the battery to bring it up to charge. Some chargers have an automatic shutoff switch that will shut the unit off when the battery comes up to a full charge, and then turn it back on when the charge falls below a predetermined level. This type of charger can be left on all the time. Other chargers must be removed to prevent overcharging. When the battery is fully charged store it in a cool, dry location out of the way of kicking feet or falling tools. A light coating of petroleum jelly on the posts will prevent any lead reaction to the elements. When spring comes the battery should be ready to go back to work for your tractor.