FAQS

Start with our Beginner Guide. It explains the main engine types in plain English and helps you choose by budget and experience. When you're ready, browse the Beginner Engines collection.

Still not sure? Email service@stirlingkit.com with your budget and what you'd like the engine to do, and we'll recommend one.

Yes. Most of our engines are real working engines that run on fuel, steam or heat, just like the full-size engines they're modeled on. A few, such as our TECHING models, are driven by a small electric motor instead, so they need no fuel at all. Every product page says how the engine is powered.

Each engine type runs on something different. The product page and manual always name the exact fuel for your model.

Why don't you send fuel? Gasoline, nitro fuel, alcohol and fuel tablets are flammable, so international postal and air shipping rules classify them as dangerous goods and don't allow them in parcels. That's why every engine ships without fuel. The good news: the fuel you need is easy to find locally.

Fuel and batteries are not included, so please buy them locally. Fuel engines often need a battery for the ignition, and nitro engines need a glow plug igniter. Some engines also need a starter to spin them up. Steam and Stirling engines usually need only their fuel and a little oil.

Some of our engines also come as a Full Set, which adds the other accessories you need to get it running (fuel and batteries still not included). See all Full Sets & bundles. Check the "What's in the box" list on the product page, or email us your model and we'll tell you exactly what to get.

Some can. Our SEMTO nitro engines are made to drop into your own RC car build, and several steam and stationary engine kits come with a small generator and lamp so you can see them make electricity. The product page says what each engine can drive.

We sell both. Every product page says which one it is. If you'd rather skip the build and run it straight away, see Ready-to-Run Engines.

It depends on the model and your experience. Every kit comes with a step-by-step manual, and you can download most manuals before you buy from our Download Manual page to see exactly what's involved.

Our engine models are designed for ages 16+. Younger builders can enjoy them with an adult supervising, especially for running fuel-powered engines.

Most products are in stock and ship right away. See everything ready to ship in In Stock: Ready to Ship.

Pre-order and restocking items are listed on our Production Updates page with their latest expected dates. High-performance engines are made in batches, and a new batch usually takes about 2–3 months once one sells out.

You pay when you place your pre-order, which reserves your engine from the production batch. If you change your mind, you can cancel for a full refund at any time before it ships.

Sometimes. Pre-order dates are estimates from the production schedule, and final testing or shipping can move them a little earlier or later. We update the latest dates on our Production Updates page, and if your order is delayed, you can wait or cancel for a full refund.

Yes. There are no price tags on the product and no prices in the package. Leave your gift message in the order notes at checkout and we'll include it in the parcel.

Looking for ideas? See our Gift Guide.

Yes, we ship to almost every country. Orders ship from our China warehouse, and many popular engines are also stocked in our US and EU warehouses for faster delivery: see Ships from USA and Ships from EU.

Standard shipping is free worldwide, with duties and taxes included, for engines, parts, tools and STEM toys.

• Express shipping is a paid upgrade, shown at checkout.
• Next-day delivery is available as a paid option for items in our US or EU warehouse.
• Rush processing is available as a paid option if you need your order handled first.

RC helicopters ship differently. See the RC Helicopter FAQ.

• China warehouse, standard: usually 7–14 days. In-stock orders placed before 5 PM Beijing time ship the same day.
• US or EU warehouse: usually 3–7 days, and orders ship within 1 business day.
• Express: usually 3–5 days.
• Pre-orders: ship according to the dates on Production Updates.

During busy periods like Black Friday and Christmas, and over Chinese public holidays such as Chinese New Year, orders from our China warehouse may take a few extra days to process and ship. Orders from our US and EU warehouses are not affected by Chinese holidays, so they're the fastest choice when you need it in time. We post holiday shipping notices on our site in advance.

• Standard shipping: no. Duties and taxes are included, so there's nothing extra to pay on delivery.
• Express shipping: duties and taxes are paid by you on delivery.
• EU orders over $1,000: ship by express, with import taxes paid by you. We always confirm with you before shipping.

Full details are in our Shipping Policy.

Enter your tracking number on our Track Your Order page. You'll find it in your shipping confirmation email.

Standard parcels usually travel with YunExpress, UBI or Sunyou (tracking numbers starting with SYUS or SYDE). Express parcels travel with DHL or UPS. If your tracking hasn't updated for a while, email us your order number and we'll check.

Tracking hasn't updated for a while? Email us your order number and we'll check with the carrier. If the carrier confirms your parcel is lost, we'll resend your order or give you a full refund.

Marked as delivered but you can't find it? Please check with neighbours, building reception and your mailbox, and allow 2 business days, as parcels are sometimes scanned before they arrive. Still missing? Email us and we'll help you file a claim with the carrier, who is responsible for parcels marked as delivered.

If you added Shipping Protection at checkout, we'll resend your order or refund you directly. See below.

Shipping Protection is an optional add-on at checkout that covers your parcel from our warehouse to your door.

With Shipping Protection:

• Lost parcel: we resend your order or give you a full refund, with no waiting for a carrier investigation.
• Stolen, or marked "delivered" but not received: we resend your order or give you a full refund.
• Priority handling: your replacement ships within 2 business days when in stock, and within 1 week otherwise.

Without it: we resend lost parcels once the carrier confirms the loss. Parcels marked as delivered are the carrier's responsibility, but we'll help you file a claim.

Either way: parts damaged in transit are replaced free, and every engine comes with our free 1-year warranty. Shipping Protection is not a warranty.

Claims for parcels marked as delivered must be made between 48 hours and 14 days after delivery. We may ask for a carrier investigation number or a police report, and we'll usually resend your order rather than refund it. Shipping Protection covers the address entered at checkout and allows one delivered-but-not-received claim per customer every 12 months.

Not always. If your order mixes in-stock and pre-order items, or items from different warehouses, we ship the in-stock items first so you're not kept waiting. Each parcel gets its own tracking number.

Prefer everything together? Tell us before your order ships.

No. All engine fuels are flammable, and international postal and air shipping rules treat them as dangerous goods that can't travel in parcels. So every engine ships without fuel, and the product page and manual tell you exactly which fuel to buy locally. Most are easy to find at a gas station, hobby shop, pharmacy or camping store.

Yes, as long as it hasn't shipped yet. Email service@stirlingkit.com with your order number and the change as soon as possible.

Visa, Mastercard, American Express, JCB and PayPal.

Check that your card details and billing address match your bank's records, then try again. If it still fails, your bank may have blocked the payment as a security check: contact them, or pay with PayPal instead. If nothing works, email us and we'll help.

Email service@stirlingkit.com with your order number before it ships, and we'll cancel it with a full refund.

Yes. Students, military members and first responders can get a special discount. See Student, Military & First Responder Discounts for how to apply.

Yes. Payments are processed through Shopify's secure checkout or PayPal. We never see or store your full card number.

The Download Manual page has the official instructions for each model. The User Guide has our own setup tips, first-start guides and troubleshooting articles.

It depends on the model: the product page and manual list what you'll need. Find the right tools in Engine Tools.

Each engine needs a specific fuel and lubricant, listed on its product page and in its manual (see the overview under What fuel does each type of engine use? above). Always use the type specified: the wrong fuel can damage the engine and isn't covered by the warranty.

It depends on the engine. Fuel-powered engines (gasoline, nitro and diesel) are loud and give off exhaust fumes, so always run them outdoors or in a well-ventilated workshop, away from anything flammable. Steam engines can run indoors on a heat-proof surface in a well-ventilated room, never on carpet. Stirling engines and electric models are quiet and fine to run on a desk or shelf.

Yes, for fuel-powered engines. Run it gently for the first few tanks: short runs at low to medium speed, with a slightly richer fuel mixture, letting it cool between runs. This lets the moving parts bed in smoothly and gives your engine a longer life. Your manual has the exact break-in steps for your model.

Follow the starting steps in your manual. Many models also have a step-by-step first-start article in our User Guide.

Let it cool down, empty any leftover fuel, and wipe off oil and residue. Before storing it, add a few drops of oil where your manual recommends to keep the moving parts smooth. Model-specific care tips are in our User Guide.

The most common causes are easy to fix:

• Too much fuel (flooding): close the needle valve a little, spin the engine with the fuel off, then try again.
• Weak spark: charge or replace the ignition battery and check the plug lead is firmly connected.
• Wrong or old fuel: use fresh fuel of the type your manual specifies.

Then look up your model in the User Guide for model-specific tips. Still stuck? Email service@stirlingkit.com with your order number and a short video of the engine, and we'll help you fix it.

Yes. Our engines and kits come with a 1-year warranty against manufacturing defects. We'll send free replacement parts or an exchange, even after you've built the kit.

The warranty doesn't cover damage from misuse, modifications, drops or the wrong fuel. RC helicopters follow a different warranty: see the RC Helicopter FAQ.

Every kit is checked before it ships, but if something is missing or damaged, email service@stirlingkit.com within 7 days of delivery with your order number, the model and photos. We'll send the part free of charge.

Tip: film a short video when you unbox your kit, and keep the box and packaging until everything is sorted. It makes any claim quick and easy.

In our Replacement Parts Center, sorted by brand and model.

Open the manual for your exact model and version and find the part in its parts list or exploded diagram, then search for that name or number in the Replacement Parts Center.

Can't find it? Email service@stirlingkit.com with:

• Your order number
• The model and version (for example, CISON V8 PRO V1.1)
• The part name or number and how many you need
• A clear photo of the part, or of the manual page with it circled

If you're not sure of the part number, don't guess: just tell us which build step it's in and we'll identify it for you. For older or discontinued models, parts depend on remaining stock, so we'll confirm what's available.

Yes. Look for it in our Replacement Parts Center, or email service@stirlingkit.com with your model and the part name or number from your manual. We'll check availability and confirm the price and shipping with you before we send it.

Parts that arrive missing or damaged are replaced free when you tell us within 7 days of delivery.

Yes, within 30 days of delivery, if the item is unused and in its original packaging. Clearance items and kits that have been partly or fully assembled can't be returned for a change of mind, but quality problems are always covered by the warranty.

See the full Returns & Refunds policy.

Yes. Items bought during promotions such as Black Friday follow our normal 30-day return policy.

Clearance items can't be returned for a change of mind. Quality problems are still covered by our warranty, so if something is faulty, missing or damaged, we'll make it right.

1. Email us first. Every return needs our approval before you send anything back.
2. Ship it from your local post office. We don't use RMA numbers, prepaid labels or home pickup. Send us the tracking number once it's on its way.
3. We'll tell you where to send it. Items from our US or EU warehouse go back to that warehouse. Everything else goes back to China, which usually takes 15–30 days in transit.

If the item has a quality problem, we cover the return shipping. For change-of-mind returns, return shipping is paid by you. Full details are in our Returns & Refunds policy.

Within 7 business days after your return arrives and passes inspection, to your original payment method. See our Returns & Refunds policy.

Once we've issued your refund, it can take a few business days to appear, depending on your bank or card provider. If it's not there yet:

1. Check your bank or PayPal account again.
2. Contact your bank or card company, as it can take some time before a refund is officially posted.
3. If you've done this and still haven't received it, email us with your order number and we'll look into it.

Yes. Email service@stirlingkit.com with the model and quantity, and we'll send you a quote.

Yes, for both small and large batches. See our Custom Engine Service.

Yes. Email cecily.wong@stirlingkit.com or see our Wholesale & Distributors page.

We'd love to. Send us a link to your channel through our Contact Us page.