Products powered by a Robin petrol engine (EX & EY) use the BR6HS spark plug. Contact your local service agent to make an order now.

Models: EX13,  EX17, EX21, EX27, EX40, EY15, EY20

Models: All engines

I recently had a customer complain about the seizure of his new motor, even though he had checked the oil and the motor was fitted with an oil alert sensor. It was discovered that he removed the motor from the carton, pulled out the dipstick and saw there was oil on it. The motor was mounted and started (and stopped straight away obviously because the oil sensor had kicked in). After several more attempts on starting at full throttle the motor seized requiring new piston, rings and conrod. The oil on the dipstick was remnants from factory testing. When purchasing a new engine, make sure to read the operating manual and double check oil levels.

Models: DY41, DY42

In certain conditions, such as high humidity, salty air, etc, the oil sensor solenoid on the DY41 & DY42 can become stuck and fails to operate. This usually happens over a period of time.

Note: At the time of manufacture the solenoid is lubricated and should always be checked as part of regular servicing (ie. make sure the engine turns off at key) of the engine.

Models: DY27

The diagram in the owners manual regarding connecting battery lead to the starter motor is a little ambiguous. If you are installing the electric start motor and it is not fitted with battery leads, make sure you contact your local Service Agent for the correct terminals to connect the battery to.

Models: Drive-units, DU53, DU53H, DU53BF, DU53HBF, DU47YD, DU47YDE, DU10YDE

On occasions, if the engine speed has been set to a fairly low (no load) level ie. under 2800rpm (Sometimes done for Flexible Pump and Vibe Shaft Drive Units), this can cause excessive vibration under load and result to damage to the muffler. A smoother performance will be achieved by setting the speed to between 3000 to 3400rpm for extended periods of use.

Models: All engines

Nearly all Robin engines require a restrictor in the intake when fitted with a Donaldson Air Cleaner (excludes Diesels DY23/27, DY41/42, Petrol EH65 engine series). Please be aware that nearly all Crommelins manufactured products have restrictors fitted to the Precleaner or the Rain Cap and that if the restrictor is removed or lost there are possibilities that a Robin engine may suffer severe surging under load, higher revs and the engine may run hot.

Models: All engines

Recently, I have had some end-users seize motors (from new) that are fitted with oil sensors. Robin sensors will not stop motors from starting. If customers repeatedly attempt to start motors without oil, they will cause the motor to seize (usually on the con-rod bearing).

Models: All engines

When fitting exhaust extensions be careful of pipe size & muffler type. The wrong parts can cause excessive back pressure and the motor to run rich, therefore fouling the plugs.

Models: Robin engines

A chart is available with the majority of repair specifications for all current and some superseded models. Contact spare parts on 1300 554 524 or free call fax 1800 636 281 for availability. Part No. EMDET1786

Models: DY engine

We have customers in the field who have run a Robin DY41 Diesel engine (fitted to a generator) for approximately 8000 hours without a fault (more than 5 years!),  we also know of two robin diesel DY27 powered generators that have done 7-8000 hours – all of these units had regular oil and filter changes but little else.

Models: All engines

When experiencing fuel in the oil, engines the first step is to check the needle and seat are in good condition. Often leaking can be caused by the fuel tank cap vents being blocked – or in extreme cases, with the tank being fitted with a non-spill cap.

Models: DY23, DY27, DY30, DY41, DY42

These engines fitted to water pumps that experience heavy and consistent
use may become hard to turn over. One cause of this is wear to the crankshaft thrust bearing. Check this by measuring the end float of the crank, it should be .004TH – .012TH (.1-.3mm). If it exceeds these specifications, replace the thrust washer.

Models: EX Engines

Align gold links on timing chain with timing dots on cam gear and crankgear.

Models: Micro Engines

Check which way the engine was stored  (vertically). If the engine is hung at the top, to try hanging with the engine down – this could be the cause.

Models:

Small engines such as Robin, Honda, Briggs & Stratton, etc. when fitted with a Donaldson or similar type of air cleaner, require some sort of restrictor to prevent the engine hunting. When replacing any part of the intake system make sure the restrictor is fitted. (An exception to this is the Robin EH41 and Robin twin cylinder motors as they do not need restrictors.)

Models: Micro Engines

The owners manual specifies 10W-30 oil. However, we have found that weather temperatures above 20 degrees can cause excess oil in the air filter of these engines. We recommend that SAE 30 monograde oil (as specified in the service manual) be used instead of a multi-grade.

Models: EX Engines

Most fluctuation problems in small engines are caused by bad fuel, dirt or water in the carburetor. We have found, however, that after the normal procedure (cleaning of fuel system) EX Series engines can still hunt. This can be caused by damage to the lower part of the carburetor insulator allowing excess cooling air across the air vent for the carby bowl.

Models:

Recently I had a customer who purchased a 9.0 HP diesel engine Model DY42 to replace his “High Speed” 6.0 HP diesel. After 3 months the motor would not start. On investigation, it was found the compression rings were seized in the piston. It was then discovered that his original motor was a 2000 RPM LISTER, which is a low RPM old style engine. Consequently, when using the same pulleys and driving a positive displacement pump it severely overloaded the new motor. When selling a replacement engine, make sure it is replaced with a similar engine! This can easily be done with a check on the model number, or even sighting the engine to replace.

Models: All engines

The most common cause of engines ‘hunting or surging’ is stale fuel evaporating, leaving residue on the main jet or dirty fuel causing partial blockage of the jet. If the motor runs smoothly on partial choke, this usually indicates main jet restriction. **Other causes can be worn or cracked early insulators or poor sealing gaskets

Models: EX Engines

If you find the EX Series engines run smoothly on idle or slight throttle
but begin to hunt or surge at high revs, check the condition of the carburettor insulator. If it is damaged on the right hand side near the blower housing this will cause the engine to hunt or surge as it will provide increased air flow across the back of the carburettor vent which will upset the fuel level. In this instance, a replacement of the insulator will be necessary

Models: All engines

This may sound obvious to many, but it is still common practice to connect NEGATIVE to POSITIVE, causing the rectifier to short out. So, when selling motors to clients who wish to fit the batteries themselves, make sure know and connect to the correct terminals.

Models: PV45SRN, PV45S, EH035, SP52CR, SP82CR

To avoid what appears to be oil leaks, it is necessary to squeeze excess oil from the element every 2-3 hours of use as the owner’s handbook states.

Models:

In the past few months, I have had several reports of wasps building nests in the exhausts of small engines. The symptoms indicate a sticky intake valve, whereas it is actually the muffler that is blocked. Usually, this problem is after a long storage period, though in one instance the muffler blocked over a weekend.

Models: PV45SRN, PV45S, EH035, SP52CR, SP82CR

Apparently, some people have noticed leaking, presumably from their ‘fuel taps’. These machine’s engines do not have fuel taps. If there is any leakage, it would be oil. However, if the oil dipstick and its seal is clean and screwed in tight it should not lose oil. As with all makes of brush cutters, be aware that damage can occur to the throttle cable bracket/ carburetor insulator if the unit is allowed to roll around, i.e. the back of a station wagon or ute, so it is important to make sure the unit is secure while traveling.

Models: EY Engines

Problem – No spark when motor fitted with electronic ignition. Test the pulser coil and exciter coil with the multimeter.

Readings should be:

  1. Pulser coil 66 Ω + – 20%
  2. Exciter coil 0.9 Ω+ – 20%

Models: All engines

Regardless of make, model or size of the engine, it is imperative that the oil level is checked frequently, e.g. after every tank full of fuel until the motor has properly bedded rings to the cylinder. This is even if the motor has a sensor unit, as the location or angle of the machine can cause false readings.

Models: Robin engines

There are 4 steps to storing your engine:

  1. Drain fuel from tank and carburetor,
  2. Remove the spark plug and squirt a small amount of engine oil into the cylinder,
  3. Replace plug and wind motor over 2 or 3 times,
  4. Bring the piston up on compression stroke.

Note: If in damp conditions, put tape over the intake and exhaust and give the unit a light spray with a mix of diesoline and oil or similar.

Models: DY23, DY27, DY30, DY41, DY42

Although the owner’s handbook specifies no oil change is required before 100 hours of running time has occurred, it is preferable to change the oil at 50-hour intervals.