Jackshaft Hsng Assembly 1001200MA

Remove the blade, remove the nut from the jackshaft pulley. Remove the 5 bolts from the cracked mandrel. Install the new mandrel. (The new mandrel is not threaded, but the bolts to mount it are self tapping bolts) Place the pulley on the mandrel shaft and tighten the nut. Then install the blade. If you feel like you need more space and don't want to scrape your fingers arms and hands you can remove the deck to do this repair.

1. Remove cutting deck from Murray tractor mower.
2. Remove the blade.
3. Remove the 5 bolts holding the mandrel to the deck. These are self-tapping bolts and extremely tight requiring a two-foot pipe extension on my socket wrench handle.
4. With the mandrel free, clamp the pulley in a vise and remove the top nut, also extremely tight.
5. The shaft of the new mandrel was not a perfect fit. I had to machine some spacers from the old parts to reattach the pulley and blade.
6. Reattach the mandrel to the deck. The old self-tapping bolts were in bad shape so I bought 5 new 5/16 bolts with locking nuts.
7. Replace the blade and reinstall the deck to the tractor.

It was very simple. I disconnected the belt, removed the blade, and removed five bolts. I put the new mandrell in place, and reused/reinserted the old five bolts, blade and belt. The diagrams on line were very helpful in seeing how they went together.

1. Removed belt from pulley attached to the Jackshaft Housing Assembly.
2. Removed pulley on upper Jackshaft Housing Assembly.
3. Remove 5 bolts holding Jackshaft Housing Assembly onto the deck.
4. Removed blade from lower Jackshaft Housing Assembly.
5. Greased new part
6. Reversed order to reinstall

Used air ratchet to take off & replace both jackshaft housing assemblies & blades.

Bought a mower lift to elevate mower this was priceless
cleaned area, removed blade, removed bolts holding assembly, put belt out of way, greased new jack assembly prior to installing, reinstalled jack assembly, replaced blade, replaced belt, lowered mower.

I removed the deck from the mower. Remove the blade bolt and washers and the blade. Removed the bolt on the jack shaft pulley, remove the pulley. Then removed the five bolts holding the mandrel on. The old mandrel fell right off. Lined up the new mandrel to the bolt holes on the deck and tighten them in cross pattern, until the were tight. The mandrel is not threaded, but the bolts are self threading. I then attached the pulley to the mandrel shaft and tightened the nut. Attached the blade then attached the deck back onto the mower. I then removed the muffler and the muffler adapter and replaced the gaskets.

Remove old jackshaft and blade and pulley. Replace new jackshaft, blade and pulley. realign belt on pulleys . Easy repair.

Replaced jackshaft assembly put blade on before attaching thru deck.. very easy. Replaced pulley for blade belt. Easiest ever.

I jacked up the front of the tractor, lowered the deck all the way down. Used my impact wrench to remove the pulley nut, then used it to remove the retaining bolts. 1 wrung off so I used a 5/16 X 2" bolt, 2 flat washers & 1 lock washer in the open hole. The other bolts I was able to reuse as they were self-tapping bolts. I actually ran them through the housing first after spraying them with WD-40. They made their own threads and I was able to bolts it back together. I used my impact wrench to install the blade from underneath. Put the belt back on, raised the deck, lowered it back down and went out & mowed the grass.