Exmark 116-2090 Splined Drive Jackshaft Lazer Z Triple Twin Ultra Vac QDS Bagger

What It Is

This is an OEM Exmark splined drive jackshaft (part #116-2090) that transfers power from the mower’s engine to the vacuum impeller on Lazer Z Triple, Twin, and Ultra Vac QDS bagger systems. It’s a critical wear item for commercial operators using high-capacity bagging setups.

Fitment & Compatibility

• Exact fit: Exmark Lazer Z Triple, Lazer Z Twin, and Ultra Vac QDS bagger models. Does not fit standard Lazer Z or non-bagger decks.
• Deck sizes: Compatible with 60” and 72” decks (verify your deck’s spindle-to-impeller distance).
• OEM only: No aftermarket alternatives exist for this splined shaft—using a non-OEM part risks shearing or misalignment.
• Check before buying: Measure the length of your current jackshaft (approx. 12.5” from spline end to keyed end). Count splines on the input side—must match 16 splines. Inspect the bearing support bracket for wear; a worn bracket can cause premature shaft failure.

Key Things to Know

• Installation difficulty: Moderate. Requires removing the bagger chute, belt, and pulley. You’ll need a puller for the pulley and a spline alignment tool (or a steady hand) to seat the shaft into the gearbox.
• Common gotcha: The shaft’s splines are easily damaged if forced. Apply anti-seize to the spline end before installation to prevent future seizure.
• Quality: OEM Exmark steel shaft with hardened splines—holds up well under heavy bagging loads, but expect replacement every 500–800 hours in commercial use.
• Price note: At $288, it’s a premium part, but a broken jackshaft will stop your bagger completely. No cheaper alternatives that fit.

Should You Buy It

If you own an Exmark Lazer Z with a factory Ultra Vac or QDS bagger and your current shaft is worn, cracked, or stripped, this is the only correct replacement. It’s a must-buy for commercial landscapers who need reliable bagging—don’t gamble with used or generic shafts. For residential users with light bagging, check if the splines are just dirty before ordering.