Forward is slow

Likely there is air trapped in the system. Try raising drive wheels (safely) off the ground and operating forwards backwards. With minimal load on the hydo pump and motor, the air should purge.

If your 1986 Cub Cadet Hydro 1210 is experiencing difficulty moving forward but works fine in reverse even after changing the transmission filter and fluid, there could be a few potential reasons for this issue. Here are some steps you can take to troubleshoot the problem:
1. **Check Drive Belt:** The drive belt is responsible for transferring power from the engine to the transmission. A worn or damaged drive belt can affect forward movement. Inspect the drive belt for any signs of wear, fraying, or damage. If the belt is in poor condition, consider replacing it.
2. **Check Tension of Drive Belt:** Ensure that the drive belt is properly tensioned. A loose drive belt can lead to slipping and difficulty in forward movement. Adjust the tension according to the manufacturer's specifications.
3. **Inspect Linkage and Connections:** Examine the linkage and connections between the control lever, transmission, and the drive system. Loose or misaligned linkage can result in improper engagement of gears, affecting forward movement.
4. **Hydrostatic Transmission Issues:** Since your Cub Cadet Hydro 1210 uses a hydrostatic transmission, there could be issues with the hydrostatic unit itself. Check for any signs of leaks, damaged hoses, or worn components in the hydrostatic transmission system.
5. **Transmission Oil Level and Quality:** Ensure that the transmission oil level is correct and that you're using the recommended type of oil. Poor-quality or incorrect transmission oil can lead to performance issues.
6. **Air in the Hydraulic System:** If there's air trapped in the hydraulic system, it can cause issues with the hydrostatic transmission. Bleed the hydraulic system to remove any air bubbles.
7. **Transmission Pulley and Sheaves:** Check the transmission pulley and sheaves for wear or damage. If these components are not functioning properly, they can affect the movement of the drive belt.
8. **Check for Obstructions:** Inspect the underside of the mower deck and the drive system for any debris, obstructions, or objects that might be interfering with the forward movement.
9. **Professional Inspection:** If none of the above steps resolve the issue, it might be a more complex problem requiring the expertise of a professional technician. They can perform a more in-depth diagnosis of the hydrostatic transmission system and identify any underlying issues.
Keep in mind that working with mechanical and hydraulic systems requires knowledge and expertise. If you're not comfortable performing these checks and repairs yourself, it's recommended to consult a qualified technician who has experience with Cub Cadet or similar equipment.

John Deere mowers, for the most part, use hydrostatic transmissions. These use an oil of some type (they vary by model) in the transaxle to provide hydraulic pressure to move the tractor. Older tractors will eventually experience some oil leakage over time due to seal wear. If the level gets too low, then you fail to move. Check the oil level in the transaxle. The location of the reservoir varies from model to model. If it is low, after determining the correct oil to use, fill to proper level. Then, start the tractor and work the hydrostatic drive lever forward and backward slowly and continuously until you get full speed operations in both forward and reverse. This can take a few minutes until all the air has been purged from the system.

Check trans. oil for debris and quantity. If level is low try topping up first and if this works it would pay to disassemble in the near future, clean the oil filter and fill with clean oil.

If it's a hydrostatic transmission, I would have the transmission looked at. You may need to "purge" the system and check the fluid level.

The ones I've done called for the drive disconnects (the rod or lever which allows you to roll the tractor when the engine is shut down) to be in the flow bypass position. They also wanted the wheels off the floor, then the engine to be started, & the direction control to be worked SLOWLY to the front & rear positions 10-12 times. Then put the bypass valve back in its 'drive' position, fire the engine again & repeat the slow cycle of the direction control. The unit SHOULD be quieter now & perform better, but double check the oil level because expelling the air may have dropped it too low.

Her is a site that has the manual.

this hydrostat drive tractor is designed to max at 5.5 mph forward, 2.5 in reverse, check linkage at pedal if you dont think your achieving those speeds

HI

Im sure you have a hydrostatic or an automatic forward and reverse right well your ****** is on its way out when it warms up it likes to crawl in this case even if you attempt to check oil or even try draining and putting in different oil its a tough one ****** is expensive


Joe

Joe

If this is a hydrostatic drive. Check oil level in transmission. If you have been running it low on oil, it may be too late for the hydrostatic drive unit. If it has a drain plug, drain it and change the oil.

There is a breather tank or hose on the top of transaxle. Remove back hitch plate from tractor.There is either an allen wrench plug or a breather hose fitting you can remove to add oil to the transaxle. Add synthetic 15w-50 or 20w-50 motor oil,Amsoil,Mobil-1,Lucas oil or Purple power are good brands to use. Do not use hydrostatic oil.it is too thin.Fill to within 1.5 inch from top which will allow air for expansion. After filling, purge transaxle by putting it it in freewheel mode ,run engine at full speed with clutch out and work the drive back and forth between forward and reverse 10 times,then it should be good to go.