Replacing rear axle seal on YM1600 – 1610

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Replacing rear axle seal on YM1600 – 1610

Post by norfolktoad »

Thanks to “agirlandhertractor” for the informative step by step guide and her excellent pictures of this procedure, which made this task relatively easy.

1 Drain oil from the transmission, but remember to use a container of at least 4
imp gals (5 US Gals)

2 Unbolt the top link unit and pry off with old screwdriver or wood chisel

3 unbolt PTO unit. Only undo the 6 bolts around the outside. If you undo the 4
Large and 2 small bolts you may well have a pile of cogs etc in the transmission housing. The PTO unit will have to be prised off using old screwdriver and wood chisel. The main drive shaft and connector will drop out as you pull the unit out. You will need to twist the bottom of the unit to the left to release the PTO lever.

3 Unbolt the 4 bolts on the hub and prise the gasket apart.

4 Remove the circlip holding the bull gear in place. You will need a pair of external circlip pliers which are at 90o.

5 Knock out the shaft by hitting the hub with a bounce free hammer. This will
Allow the bull gear to be removed from the transmission housing.

6 The shaft will come out of the housing with another circlip and a large washer
Attached, you may have to wiggle the shaft out to get the washer around the internal casting within the axle housing.

7 Remove the circlip and washer.

8 Either press off the bearing with a bearing press or use the holes in the hub and long bolts as a means of pushing off the bearing. Once loose from the outer end of the shaft it will have to be driven off the splined end of the shaft.

9 Prise out the seal from the hub.

10 Remove the old collar; this can be done using a punch and hammer.

11 Clean up the shaft and hub and remove gasket material from all surfaces.

12 Check the transmission oil screen is clean. No need to remove it if clean as it can be seen from the PTO aperture.

13 Smear a little grease on the shaft surface and press on the new axle collar. It may need tapping on gently with the old seal as protection.

14 Grease the collar and press on the new seal remembering the flat side to the outside. This may have to be driven on using the old seal again as protection.

15 Push on the bearing so its fits into the hub. This will need driving home or use a press.

16 Reinstall the outer circlip and the washer. Place new gasket on hub.

17 Push the shaft into the axle housing... You may have to wriggle it to get the washer past the internal casting in the housing.

18 Once in the housing tap the hub so the shaft goes into the inner bearing. The bearing will probably come out of it housing. Therefore gently knock it back, so about ¼ inch of the shaft is exposed in the transmission. Reinstall the bull gear on the shaft. Gently knock the hub with a hammer and alternately knock the thick part of the bull gear until the circlip grove is exposed. Tighten up the 4 bolts on the hub.

19 Put circlip on to secure the bull gear

20 Reinstall PTO unit. Secure new gasket with a little grease. Pack the main shaft coupler with thick grease to help keep it in line with the PTO unit. Unbolt the bracket which old the PTO sector and tap from inside transmission as far as it will go. Make use the sector is as far forward as possible.

21 Push the PTO unit in and hopefully it will line up with the main shaft (you may have to turn the PTO to get it lined up).

22 Tighten up the PTO selector shaft and loose fix the PTO unit bolts.

23 Check the PTO engages. With the PTO engaged the splined shaft should not
Turn. With the clutch depressed the PTO should turn easily. Select neutral on
The PTO selector and the PTO should turn easily.

24 Tighten up all bolts.

25 Reinstall the top link with a new gasket.

26 Replace rear wheel. Lift arms and PTO guard.

27 Fill transmission to upper mark on dip stick with Tractor Universal Fluid. May require about 15 litres (3 S gallons). Checks for leaks and operation of the PTO when engine running.

This proved to be a relatively simple task. Just take your time and keep everything clean.

Parts used Rear Axle Collar, Oil seal 57 75 12mm, Gasket paper or individual gaskets (hub, top link and PTO), grease, and approx. 15 - 20l of tractor universal fluid either SAE 10W-20 or 10W-30 which ever is available.

Tools required ½ drive socket set, ring spanner set, 90o external circlip pliers, selection of old screwdrivers and wood chisels, non bounce mallet, use of a bearing press, hammer and punches, scraper for removing old gasket.

Hope you find this useful.

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Re: Replacing rear axle seal on YM1600 – 1610

Post by winston »

Nice set of instructions. Thanks for posting