Keeping combines on the move

Daily maintenance and fire prevention checks are essential to keep combines working safely and efficiently in high temperatures, writes Derek Casey

OUR recordbreaking dry summer has meant combines have been asked to come into action much earlier than usual this year.

It’s a busy and testing time for these kingpin machines, with long hours in the field sure to throw up some unwanted breakdowns.

Thankfully ground conditions appear to be excellent in what is probably the only silver lining in farming terms from the drought.

PREVENTING FIRES

These warm temperatures of mid to late 20s are leading to tough working conditions for both man and machine.

The unusual conditions seen so far in harvest 2018 also present some added risks for dust and crop residue fires as machines work hard in hot conditions.

For a few unfortunate operators, each year disaster strikes when an expensive combine goes up in flames in a matter of seconds.

To reduce the chance of this happening, be rigourous in your daily ritual of removing fuel for potential combine fires, i.e. built-up grain, chaff and dust layers on the machine.

Warn drivers to have a regular cleaning schedule each evening before finishing up.

Use an air compressor every day to blow away any crop residue that has wrapped around bearings, belts and other moving parts.

Remember: residue can catch fire even when the machine is parked up for the night as the engine heat slowly dissipates without the cooling effect of the machine being in motion.

Specific areas to blow out include:

÷The engine, especially the exhaust manifold, turbocharger, muffler and exhaust pipe ÷Hydrostatic pump, motor, hydraulic lines and tubes ÷Brake and transmission housings

÷Electrical components ÷Engine drives and all moving parts ÷Batteries and battery cables ÷Straw chopper drive gear compartments

It is possible to eliminate some heat sources from the combine.

Covering up hot exhaust surfaces and replacing any exposed electrical wiring is a good place to start.

Worn bearings and belts can easily generate enough heat to make fine dust and crop residue catch fire.

While the hope is that it doesn’t come to it, in the event of a combine fire you have to be prepared.

Always keep at least one fully-charged and certified dry chemical fire extinguisher in the combine cab.

Mount a second fire extinguisher on the outside of the machine that can be reached from ground level.

Finally, remember to check and recharge any old or partially discharged extinguishers if you haven’t done so already.

REGULAR ROUTINE

Once the harvest starts the aim should be a regular combine maintenance routine.

Carrying out this well-rehearsed routine in the morning rather than at night (with the exception of cleaning off the chaff and dust) works best for a couple of reasons.

First of all you have good lighting sufficient to have a clear look at the machine in order to find potential problems like worn bearings or cracked parts.

The other benefit is that the combine will be cooler and therefore easier to work around than it would be after a long day in the fields.

Some operators argue that for certain jobs, for example greasing, the grease will travel in more effectively around warm bearings than cold ones.

This is a fair point, but the main thing to remember is you are trying to get the operator into the habit of doing all vital checks at a given time of day.

And don’t forget the golden rule: switch off the engine and remove the key before carrying out any maintenance. Daily checks

All 10 hour nipples should be greased on a daily basis. A good habit to get into is doing a couple of related jobs in one sequence.

For example, when filling the machines with fuel, check both engine and hydraulic oil levels, and then check the radiators to see if they have sufficient water – critical during long, hot days when engine demand is at its peak for high yield crops.

Stone traps do not necessarily need to be checked every day if the crop is generally clean, but in modern combines access is simple so it is worth taking the 10 seconds needed to have a look.

The header is a very important part of the combine and contains a lot of moving parts. Every day you need to look for any serious damage to the knives, skids or fingers.

The wobble box should be getting a full inspection in a pre-season maintenance programme at your local dealer or in your own garage. A wobble box working for around 200 hours per season will generally last for anything from eight to ten years depending on the operator.

Every two days you should check and clean the air filters, grease any 25-hour or 50-hour nipples, and check chain tensions - particularly the feeder house chains.

On some machines the feeder house chains sit on pieces of timber that look similar to roof slats. Over time, the chains can wear into these timbers and slacken. Watch out for broken or bent chain reels on the intake as well.

Other common parts that tend to wear out over time include bearings, chains, belts, sprockets, sickle sections and injector lines. A good visual inspection is key. Check belt tensions for wear and tear.

How do you know if a belt is slack? You should only be able to get half a twist by hand on a belt that is properly tensioned. If you can twist a belt all the way around, 360 degrees, it needs to be tensioned to prevent excessive wearing and subsequent replacement.