When a neighbor departed I purchased from her a Murray 14.5hp 40″ lawn tractor. The engine fired but the tractor wouldn’t budge. After some basic repairs I got it running fine and have kept it going the past 3 years. Since I use it over rough ground it occasionally needs repairs – such as replacing shattered mandrels when the blades hit concealed rocks, beating out the housing from rock collisions and replacing the mower drive belt. I now use my big tractor with a pto bush hog for the rough ground and tough grasses, and hope to nurture this lawn tractor along and use it for more confined areas such as the chicken paddocks and between the fruit trees. I also use a scythe for occasional clearing.
All was well until a couple days ago when after cutting a chicken paddock area and closing the gate, I shifted the gear selector to forward and, though the engine continued to run, the tractor was stationery. I selected each of the other forward gears and the reverse position and the tractor did not move. A new challenge.
Today I worked on the tractor. My reasoning was the problem could be one of 3 things: the gear lever was not communicating with the transaxle (transmission); the transmission was defective; the transmission and the gear lever were fine but the transmission was not receiving power from the engine.
First step was to access the transaxle.
I disconnected and removed the battery from its housing.
With the battery removed you can see the big pulley which is attached to the transaxle. The engine at the front of the tractor turns two drive belts – one belt rotates the mower blades and the other, which is well concealed, provides the power to drive the wheels via the transaxle.
Also visible above the pulley is a large spring. This is attached to the idler pulley. There are three pulleys – the pulley the engine turns, the pulley attached to the transaxle and the idler pulley which keeps the belt taut when the tractor is moving.
So what was wrong – there was a belt on the big transaxle pulley so it seemed the transaxle must be receiving power from the engine. I selected a gear and pushed the tractor and to my surprise the big pulley turned. I put the gear selector in neutral and pushed and the pulley did not turn. I selected reverse and pushed and the pulley turned again but in the opposite direction. I then breathed a big sigh of relief. The gear selector was working, the transaxle was working and the belt must be loose. I navigated to the engine end and felt underneath and found the pulley which drives the belt to the transaxle and the belt was also there and intact but it was not on the pulley. So the belt had come off the pulley. Now why had this happened. In maneuvering my hand under the engine I pulled on the engine and it rocked forward. It typically has 4 engine bolts and the rear two were missing. Incidentally when I first got the tractor the same 2 bolts were missing and I replaced them – so I was familiar with these bolts. I surmise that when I engaged the gear the engine rocked forward which meant the pulley underneath rocked back and the belt came off. Probably also because the belt has stretched. Rather than replace the belt I decided, for the time being, to reseat the belt and order and install the 2 missing engine bolts.
But it is very difficult to work on the pulley under the engine – it is barely accessible and there is no room to apply leverage on the belt to force it back onto the pulley. Then I remembered the idler pulley – if I could move it aside it would free up a lot of belt slack. I tried approaching the idler pulley from underneath and then concluded that a long crowbar via the battery housing would secure a good grip and move it aside, which it did. But I could not hold the crowbar in place at the rear of the tractor and reseat the belt under the engine at the front of the tractor at the same time. I needed a helper.
I cut a piece of strong wire and shaped it into a loop. Then with the crowbar I pushed the idler pulley to the side and with the wire band secured part of the idler assembly to the shaft of the gear selector which acted as my anchor. With the idler pulley now held out of the way by the wire band, it was then a simple matter with one hand to reseat the belt over the engine pulley.
When the engine bolts arrive I will complete the repair and in future make a careful check that all the engine securing bolts are in place.