Modeller Support

How to send Macgregor/Saito Engines for repair

If you need to return your Saito Four-Stroke Engines for investigation or repair, please send it to:

MacGregor Industries Limited
Modeller Support
Cordwallis Street

We recommend that all parcels and packages are returned to us via Royal Mail Special Delivery, if you wish to send the item(s) to us via normal post it is AT YOUR OWN RISK. The original packaging, or equivalent, provides excellent protection and should be used wherever possible. Remember that MacGregor Industries does not accept responsibility for damage for loss occuring during transit to us.

Include a note giving brief details of the problems that you have experienced, or the work that you wish us to carry out. Details of the events leading up to the problem are useful as these provide invaluable clues. Please do not rely on a reference to a telephone conversation to convey details of the fault. Our telephone engineers work under great pressure and it is likely otherwise, that vital details will be missed. Please print your NAME and ADDRESS in BLOCK CAPITALS so that we can correctly identify you. Our records are accessed and filed by means of the customer names and an indecipherable signature, with no further identification, will inevitably cause delays in dealing with a progress or payment query.


Upon receipt, all items sent for repair are examined and a full written report is given detailing the examination results, any necessary repairs and the associated costs. Since any fault diagnosis usually involves effecting a repair, we do not normally send an estimate before completing the work. If you specify that you require an estimate only, we will endeavour to give one but the figure is necessarily approximate. We reserve the right not to service or repair any Saito product not originally supplied by us. When such items are accepted an additional service charge will apply.

Please note that in the case of an examination where no fault is found, the investigation cost must still be paid in full.

If you suspect that your repair is to be covered under warranty please supply a copy of your sales receipt as proof of purchase.


Payment may be made by Cheque, Postal Order, Credit Card (Visa, Mastercard or American Express) or by Debit Card. Credit and Debit Card payments are accepted by telephone. For Visa, Mastercard and American Express, the card number and expiry date are needed. For Debit Cards, the card number, the issue and expiry date are required and for a Switch card the card issue number is also required. The name and address of the cardholder is required for all card transactions. Once payment is received, the goods are returned to you by a secure postal method. If you can provide a business address we can alternatively send the parcel using the Securicor 24 hour service . If we advise that the repair is uneconomic, our only charge is the return post and packaging.

DIY Checks

Before returning an engine to us, please eliminate the following common user errors. Please remember that the examination cost must be paid even if no fault is found:

1. The most common error is to run four stroke engines too lean. If the engine is rough running, cuts abruptly without spluttering or is difficult to set up, please try opening the main needle at least half a turn. Always fly the engine at a richer setting than found during ground runs.

2. Saito engines benefit from prolonged running in. Please do not be in a great hurry to lean your engine out. It is not un-common for a Saito to need at least four gallons of fuel before starting to give its best. If you feel that the engine is not delivering enough power to fly your model safely when running rich, please bench run it until you are happy with its performance (Please use a suitable engine test stand). Bench running also allows you time to become familiar with the engine.

3. If in doubt, change the plug!

4. If the engine runs ok on the bench but gives trouble in the model, then the problem probably lies with the installation. Please check that the tank and fuel lines are free from splits and leaks. The fuel tubing need to be of sufficient bore. Check that the clunk does not meet with the back of the tank, which can restrict fuel flow. Do not use an over-size tank. Large quantities of fuel surging to the back of the tank on take-off can raise the pressure in the fuel line and cause the engine to flood. While the engine is running-in at a rich setting, limit yourself to gentle aerobatics. Always be alert for a rich cut. Fly high enough to be able to land safely if the engine rich cuts.

5. If in doubt, read the instructions.

6. If the engine is mounted inside a cowling make sure that you have approx 3 times the exit area to entry area. Some installations benefit from a baffle inside the cowl to restrict/direct cooling air over the cylinder.