Welcome to the official FridayParts FAQs hub! As a trusted supplier of aftermarket parts for heavy equipment, we receive a wide range of practical questions every day—from machinery owners, mechanics, and operators alike.
To help you find the right parts faster and solve common issues more easily, we’ve gathered our most frequently asked questions right here. This is a living document. Our team will continue to update it with new questions and answers based on your feedback. Think of it as your go-to guide for troubleshooting and parts buying. Let’s dive in.
FAQs: Real Customer Questions Answered
Q: How do I know which glow plugs to buy for my Kubota D1105 engine?
You need to confirm if your engine’s cylinder head is threaded for M8 or M10 glow plugs. The Kubota D1105 engine was manufactured with two different glow plug thread sizes. Ordering the wrong size is a common mistake.
If you aren’t sure which size you need, the easiest way to guarantee a match is to take a clear picture of your cylinder head and send it to our customer service team. We can help you identify the correct size.
Q: Does a “complete cylinder head assembly” always include the camshaft?
No, not for heavy machinery. On cars, a cylinder head assembly usually comes with the camshaft. But for construction and agricultural machines, a “complete assembly” normally means the bare cylinder head plus valve parts like valves, springs, and seals. The camshaft is almost always sold separately.
Tip: Always check the product description to see exactly what’s included. Don’t assume the camshaft is included—most of the time, you’ll need to buy it separately unless it clearly says otherwise.
Q: Can I order a complete engine assembly with just the model and serial number?
Unfortunately, no. To make sure the engine matches, we need a clear photo of the full engine nameplate, including engine RPM and power details.
Engine makers often have different versions of the same model, with different power and RPM settings. The model and serial number alone don’t show all these details, but the nameplate does. Before ordering a complete engine assembly, take a clear picture of the engine nameplate.
Q: Do I need to provide extra info to order an engine overhaul kit for my Kubota D1105 or ZB600?
No! This is one of the easy ones. Unlike many other engines that come in different versions, the Kubota D1105 and ZB600 use standardized internal components. For these models, we provide one complete overhaul kit that is designed to fit correctly.
There is only one overhaul kit for the Kubota D1105 and ZB600 engines. You can confirm it directly by model—no need to request a price quote.
Q: I run my Komatsu PC300-8 in a hot climate. What kind of hydraulic oil should I use?
For continuous work in high temperatures, we recommend SAE 46 hydraulic oil.
Viscosity means how thick the oil is. When it gets hot, oil becomes thinner. If it’s too thin, it won’t protect the hydraulic pump well, which can reduce performance and cause faster wear. SAE 46 is thicker and holds up better under heat, so it keeps better protection.
Tip: Always choose hydraulic oil based on your working load and the outside temperature. Using the right oil is an easy way to extend the life of your hydraulic system.
Q: The valve plate in my hydraulic pump overhaul kit doesn’t fit, and the nameplates are gone. What now?
Don’t worry, there’s a way to solve this. Just take a clear photo of your old original valve plate and send it to our team for identification.
Many hydraulic pumps are directional, meaning they can be left-hand (counter-clockwise) or right-hand (clockwise) rotation. The valve plate inside has to match that rotation. If the nameplate is missing, the best way to find the right replacement is to match it with the old part visually.
Tip: When you take a pump or motor apart, don’t throw the old parts away right away. Keep them until the new ones are installed and working. They’re the best reference when part numbers are not available.
Q: I bought a seal kit for my excavator, but it doesn’t fit. The nameplate is worn out. What went wrong?
Your machine may have a non-original hydraulic cylinder from a past replacement.
This issue is very common on used equipment, such as the 2012 Hitachi excavator. Operators regularly swap out parts as machines age. Even with your exact equipment model, the original seal kit will not fit an aftermarket hydraulic cylinder.
Heavy use or frequent modifications often wear away the machine’s nameplate, especially steel-stamped plates. Measure your hydraulic cylinder before ordering a seal kit, so your new parts fit perfectly.
Check our guides here: “How to Measure Your Hydraulic Cylinder” and “How to Select Hydraulic Cylinder Seal Kits by Size”.
Q: Why do I see two different prices for what looks like the same part?
You may see an older product listing that shows an outdated price.
If you paid a higher price, please do not worry. Some of our listing pages are old and we have not updated them yet. We have adjusted our prices recently because raw materials are in short supply and overall costs keep rising.
If you run into this issue, you can reach out to our customer service team. We will check your order and refund the price difference based on your specific situation.
Q: I found a number stamped on my old flexible coupling. Can I just order a new one using that number?
No, you shouldn’t rely only on that number. The same stamped number is often used on couplings of different sizes and types.
The number stamped on the part often refers to the casting mold, not the final part’s specifications. The two most important details are the overall size and the design of the center hole.
How to avoid this issue:
- First, confirm the size (e.g., “16size”).
- Then, look at the center hole. If it has a “stepped” design, you need an AS model (e.g., 16AS). If it has a straight, non-stepped hole, you need the standard A model (e.g., 16A).
Q: How do I know if a solenoid valve is “normally open” or “normally closed”?
Just check the product title or description for NO or NC — these tell you the valve’s default state when no electricity is applied.
- NC (Normally Closed): The valve is closed, blocking flow. Power is needed to open it.
- NO (Normally Open): The valve is open, allowing flow. Power is needed to close it.
Tip: We are working to add this critical parameter to all relevant product descriptions. If you don’t see it listed for a part you need, just ask our team! We’ll find the information for you.
Q: I installed my new ECU, but I’m getting a “programming error” code. What’s the problem?
Even though we pre-program the ECU (engine control unit) based on standard engine specs, some machines still require extra parameters linked to the vehicle’s specific VIN.
The ECU needs to communicate with both the engine and the specific machine it is installed on. Our standard programming covers the engine, but if it doesn’t match the machine’s unique VIN-related settings, a “programming error” code may appear.
Tip: When ordering an ECU, please provide the engine nameplate information and the full VIN of your machine. This helps us program the ECU correctly for your exact setup and avoid compatibility issues.
Q: I’m looking at a Parker cycloidal motor. The part number matches except for the last four digits. Is it compatible?
Yes, it should be compatible.
For Parker cycloidal motors, a difference in the last four digits of the part number usually does not affect compatibility. Those last digits are often just non-critical details like production batch, small revisions, or surface finish. They don’t change how the motor fits or works. The main specs, like mounting size, shaft, and displacement, stay the same.
This is generally a reliable rule for Parker motors, but if you’re not sure, it’s still a good idea to double-check with our team.
Q: How can I be 100% sure I’m ordering the correct Kubota injection pump?
The most reliable way is to send us the nameplate from the machine itself, not just the engine nameplate.
Kubota engines are used in a huge variety of equipment, and the same engine model can be paired with different injection pumps depending on the application. Currently, there is no universal database to accurately identify the pump using only the engine serial number. The machine’s nameplate gives us the context needed to cross-reference and find the exact part.
When asking about a Kubota fuel injection pump, always try to provide the machine make, model, and a clear photo of the nameplate. This helps save time and avoids ordering mistakes.
Have a question that wasn’t answered here? Reach out to our expert customer service team anytime. We’re here to help keep your equipment running smoothly.
