Miller Trailblazer 325 Problems (Plus Quick Fixes)

Miller Trailblazer 325 is a very powerful fuel-efficient welder, and it has been very popular in the market for years. But have you ever experienced problems with your Miller Trailblazer?

Well, we did have some issues with it, and I am pretty sure you did too, as you are here today. Solving or understating these problems can be tricky, and the user manual can be rather confusing.

Worry no more because today we will discuss about the Miller Trailblazer 325 problems and quick fixes to solve all these problems.

Miller Trailblazer 325 Problems

Specifications of the Miller Trailblazer 325

  • Engine weld speed: Auto-speed™ technology
  • Fuel type: Gasoline
  • Output: 325 A at 28 V, 100% duty cycle
  • Current type: DC
  • Net weight: 486 lbs
  • Warranty: 3 Years

What are the tools required to fix the Miller Trailblazer 325?

Fixing a welding machine is not an easy task and you will need a few tools at hand. Always make sure to keep all these tools within reach before fixing your welding machine.

The tools you will need are as follows:

  • Grinders
  • Extra Fuel
  • Filler Metals
  • Screwdriver
  • Spare Parts in case of a damaged part

What are the common problems with the Miller Trailblazer 325 and how do you address them?

Even though we are talking about the Miller Trailblazer, most welding machines can suffer from these common issues.

Below, we will look into all these issues in detail. Moreover, we will also share with you the fixes you can do in case of these idling problems.

• Cracks on the machine

The most common problem Miller Trailblazer 325 faces is a crack. Whenever a welding machine with cracks is used repeatedly, the crack grows over time until the machine would no longer function, leaving it idle.

Solution: If your welding machine suffers from cracks, solving the problem is pretty complicated. It is not the work for any amateur and you will need professional repairman knowledge about the functionality of a welding machine.

The solution is to fill the cracked area with filler metals or any other recommended material.

Hence, to avoid cracks, you need to maintain the correct grinding time according to the Trailblazer manual and make sure to not overdo. Also, make sure to correctly fit all machine plates and edges and recheck before using them because this is the main reason for cracks.

Moreover, always use recommended heat and clean the machine on a regular basis to remove dust and other debris.

• Undercuts

Undercut in any welding machine occurs due to three main reasons: using a higher voltage rating than the recommended rating; or using a thicker welding rod; or placing the welding rod in the wrong location or angle.

Another cause of undercut is when a welder is welding any metal at a rapid rate of motion.

Solution: If you wish that your Miller Trailblazer 325 not suffer from undercut problems, follow these methods. When welding metal rods, always double-check the amount of weave you’re using.

Also, stick to the prescribed welding rod size and avoid using too big welding rods. Furthermore, use the welding rod in the proper position and avoid using it vertically.

Make sure to check the speed you’re using, and you’re not going faster than the recommended pace.

• Blocked parts and porosity

Porosity is also very common in Miller Trailblazer 325 and can be caused by corrosion, water, paint, oil on parts of the machine itself. Also, when you need less gas for shielding, porosity can quickly occur in your Trailblazer 325.

If you do not know what porosity is, read below to better understand.

Porosity is a condition where gases such as Oxygen, Nitrogen, and Hydrogen are absorbed and left free of solids after being immersed in the welding metal.

Solution: You need to follow many necessary steps carefully to ensure that the Trailblazer 325 does not suffer from porosity. Re-brake the welding machine and clean it often, especially the machine plates. Also, make sure the plates are completely dry and devoid of any dampness or water.

Check the welding torch that comes with the machine and repair any leaks. Finally, inspect the gas nozzle’s condition and clean it more frequently.

Whatever you do, do not make the mistake of using all types of consumable welding rods. Only use the recommended ones from the manufacturers.

• Spatter

Spatter happens when a few drops of a molten metal gets too close to the welding arc. Spatter is especially noticeable when using the gas metal arc welding method, often known as GMAW.

Spatter can also occur when utilizing a large amount of power with the wrong polarity or when using inadequate gas for shielding during the welding process.

Solution: Spatter issues can be easily avoided with a few simple tricks. Rather than using a high current, make sure to use the recommended current. Moreover, increase the torch-plate angle to the appropriate angle.

Before starting the welding operation, double-check the arc length. Furthermore, ensure that the gas flow rates and polarity are proper and that they are set to the required values.

Last but not least, the gas nozzle should be cleaned on a regular basis when you see any types of spatter problems.

• Machine deformation

Many Miller Trailblazer 325 users complain about the deformation of the machine, and it is mainly caused by the welding rod contracting and hardening over time.

Moreover, deformation can also be caused by a variety of factors, including incorrect welding sequences and inadequate clamping.

Solution:  The first and foremost solution to avoid the deformation of the machine is to clean the welding rod regularly. Use the suggested welding sequence, changing it whenever you see distortion, and making a few passes throughout the welding operation.

Do not use any fancy welding rod; stick to the welding rod that is recommended by the manufacturer and correctly weld all sides.


Miller Trailblazer 325 problems are very common problems that users face during welding. If you do not adequately know how to detect the issues, finding the solution to the problem won’t be easy.

Hence, today our article focused on the ideal Miller Trailblazer 325 problems and the solutions. Make sure to read this guide carefully before you go and try out the solutions yourself.