Exmark 103-0700 Jackshaft Kit Lazer Z Review

Overview

The Exmark 103-0700 Jackshaft Kit is a critical replacement part designed specifically for the Lazer Z series of zero-turn mowers. This is not a mower itself but a precision-engineered drivetrain component that transfers power from the engine to the hydrostatic pumps. It’s built for commercial operators and serious estate owners who rely on the Lazer Z’s legendary durability and need to restore factory-level performance after wear or damage. If your Lazer Z is showing belt slippage, vibration, or uneven cutting, this kit is the solution.

Who Should Buy This

1. Commercial landscape crews – If you run a fleet of Lazer Z mowers and need to minimize downtime, this genuine Exmark kit ensures exact fitment and long-term reliability compared to aftermarket alternatives.

2. Large property owners with 3+ acres – When your mower sees heavy weekly use, the jackshaft assembly wears out faster. This kit is for owners who prioritize keeping their machine in peak condition rather than patching it together.

3. DIY mechanics who do their own repairs – If you’re comfortable with basic tools and have a service manual, this kit lets you rebuild the drivetrain at home, saving hundreds in labor costs.

4. Anyone experiencing drivetrain noise or vibration – If you’ve already ruled out belt or pulley issues and the problem persists, this kit is the targeted fix for worn bearings, bent shafts, or damaged housings.

Key Features Breakdown

• Genuine Exmark OEM Part – This isn’t a generic replacement. It’s built to Exmark’s exact tolerances, meaning zero modification needed. The bearings, shaft, and housing are matched to the Lazer Z’s specific load requirements.

• Complete Assembly – The kit includes the jackshaft, bearings, spacers, and hardware. You don’t need to chase down individual components, which is a huge time-saver for busy operators.

• Steel Housing with Precision Bearings – The housing is heavy-gauge steel with sealed bearings rated for high-speed continuous operation. This prevents the slop that leads to belt wear and uneven cutting.

• Direct Fit for Lazer Z Models – Compatible with most Lazer Z series from the mid-2000s onward. Check your serial number, but this is the standard part for the vast majority of those machines.

• Replaces Worn Drivetrain Components – Over time, the jackshaft bearings can fail from dust, debris, and heat. This kit restores smooth power transfer and eliminates the “chattering” or “clunking” that signals impending failure.

Pros

1. Restores factory-smooth operation – After installation, the mower drives and cuts like new. No more belt flutter or uneven deck response.

2. Saves you from buying a new mower – A $548 kit can extend the life of a $6,000+ mower by years. That’s a no-brainer for commercial users.

3. All-in-one convenience – No need to source bearings, seals, or spacers separately. Everything arrives in one box with clear part numbers.

4. Durable construction – The steel housing and sealed bearings are built to handle the heat and debris of commercial mowing. Expect 1,000+ hours of service with proper maintenance.

5. Time-efficient repair – For an experienced mechanic, this swap takes about 2 hours. That’s a fraction of the time spent diagnosing and replacing individual parts.

6. Genuine warranty support – Exmark stands behind their OEM parts. If something is defective, you get a replacement without the hassle of fighting with third-party sellers.

Cons

1. Price is steep for a single component – At nearly $550, this is an expensive part. For casual homeowners, it might make more sense to sell the mower and buy a newer one.

2. Not universal across all Lazer Z generations – You must verify your model number and serial range. Buying the wrong kit means return shipping and downtime.

3. Requires mechanical skill – This isn’t a beginner-friendly swap. You’ll need a floor jack, basic wrenches, and the ability to safely support the mower deck and frame.

4. No instructions included – Exmark expects you to have a service manual or online access. If you’re not comfortable without a step-by-step guide, budget for a shop to do the install.

Bottom Line

The Exmark 103-0700 Jackshaft Kit is the right fix for a worn Lazer Z drivetrain, but it’s not for everyone. If you’re a commercial operator or a serious property owner who needs to keep a high-end mower running at peak performance, this kit is a smart investment that pays for itself in avoided downtime and extended machine life. For casual homeowners with a single-acre lawn, the cost and complexity may push you toward a newer mower instead. But if your Lazer Z is already paid off and you have the skills to install it, this kit will give you years of smooth, reliable cutting. Highly recommended for the right buyer.

Frequently Asked Questions

Q: How do I know if my Lazer Z needs this jackshaft kit?
A: Common symptoms include a growling or grinding noise from the rear of the mower, belt vibration that doesn’t resolve with new belts, or the mower pulling to one side. If you’ve already replaced belts and pulleys and the problem persists, the jackshaft bearings are likely shot.

Q: Will this fit my Lazer Z from 2008?
A: It fits most Lazer Z models from the mid-2000s onward, but you must check your serial number. Exmark changed jackshaft designs around 2012 for some models. Look up your mower’s serial on Exmark’s parts diagram to confirm compatibility before ordering.

Q: Can I install this without removing the deck?
A: Technically yes, but it’s much easier with the deck off. You’ll need to support the mower frame on jack stands, remove the rear wheels and fenders, and access the pump area. Most pros drop the deck first for better access. Plan for 2-4 hours if you’re experienced.