My question is I need to replace the drive belt on my 2004 Tiger Cub, is all you have to do is release the spring tensioner on deck belt and then release the tensioner on the drive belt and replace, is there any trick to getting those springs off, Thanks

To replace a transmission drive belt on a Cub Cadet LT1046 you need to remove the deck, preferably put the front wheels up on blocks or stands, unplug the PTO power (directly under the engine, which can be a pain ) You need a 5/8" socket to get the bolt out of the PTO pulley assy.(electric clutch). If you don't have an impact wrench take a spark plug out and push rope into the hole. This will bind the cylinder and keep the drive shaft from turning. Remove rope and replace plug when finished. Battery and/or spark plug wires should be removed for this process for safety.
The PTO may be stuck on there so you may want to tap it with a hammer and a block of wood carefully to release it. Loosen old belt from tensioner pulley. Lower engine pully on drive shaft, below pully "keys". It may be difficult to remove. Spray with "PB Blaster" or similar bolt loosener spray. Remove old belt from engine pulley first, transmission pulley last. Remember how belt goes around pulleys before doing so, make a diagram to help.

You'll need to put the belt on the transmission pulley first then thread the belt up to the engine pulley. Thread your belt back through the pulleys and tensioner (make sure your spring is strong enough to tension the belt or buy a new one).

The PTO pulley is "keyed" on the shaft. Replace bolt and washer. Torque bolt to 38-50 ft. lbs. using the rope meathod as described before. Put your deck back on and you're ready to mow again

It looks like in this manual there is a belt that ties the two deck spindles together the manual calls it a timing belt and looks like it is coged and there is a idler pulley that keeps this belt tight, that second spring pulls on the arm that the pulley is mounted on giving it spring tension If it is a timing belt I would look under the deck and make sure one blade is pointing forward and the other pointing sideways so they dont hit each other when passing.I have not seen anything like that sense the first Cub Cadet the made which did not have a Number because there was only one . Cub Cadet LTX 1040 Lawn Tractor Parts Manual

2004 Ford Freestar:
Accessory belt drive removal and installation:

1.Put the vehicle in neutral, and put it on hoist.
2.Rotate the accessory drive belt tensioner counterclockwise.
3.Push the spring clip towards the belt tensioner to lock the accessory drive belt tensioner in place and remove the belt.
4.To install the accessory drive belt, on the engine, rotate the accessory drive belt tensioner counterclockwise till the spring clip releases.
5.Install the belt.

Changing the Blade Drive Belts:
a.Set the parking brake. Remove ignition key and both spark plug caps.
b.Unscrew the wing nuts from the deck covers and remove both covers.
c.Using a 3/8" socket breaker bar or socket ratchet insert the drive end into the 3/8" square opening in the lower idler arm assembly and push the idler arm counterclockwise. While holding the idler arm back, loosen the blade drive belt from the pulley and slide the belt away from the pulley.
d.Remove tension of the PTO belt by moving the belt tensioning rod. Loosen the belt retaining bolt.
e.Pull the tensioner pulley away from the belt and remove the PTO belt then remove the blade drive belt.
f.Reverse the process to install the belt.

MTD uses several different configurations. Electric PTO's are tensioned all the time by an idler pulley on a spring loaded bracket. Manual PTO's with an engagement lever have a movable bracket attached to the lever via a cable that will tension the belt when the lever is engaged. Another configuration is the deck engages when the deck is lowered with the deck height lever and disengaged when the deck is raised. In this case the belt is tensioned by a large spring from the rear deck support bracket to a mount on the transaxle and tension is released by a rod that pull the deck forward when it is raised.

To replace a transmission drive belt on a Cub Cadet LT1045 or LT 1050 you need to remove the deck, preferably put the front wheels up on blocks or stands, unplug the PTO power (directly under the engine, which can be a pain ), use an impact wrench (you need the speed of the impact wrench because the engine will turn) and a 5/8" socket and reverse the bolt out of the PTO.

The PTO may be sized on there so you may want to tap it with a hammer and a block of wood carefully to release it. AT this point remove the 4 engine mount bolts from underneath (1/2" I believe). You will need to remove the left steering nut and arm to have access to the 4th bolt. Do not remove or replace engine mount bolts with impact wrench or bolts may break. Loosen old belt from tensioner pulley. Place pry bar under engine to slightly lift engine and move aft to expose belt from pulley and remove from pulley. Remove old belt from engine pulley first, transmission pulley last. Remember how belt goes around pulleys before doing so, draw a map if needed.

You'll need to put the belt on the transmission pulley first then thread the belt up to the engine pulley. Carefully push engine back into place and exhaust pipes into forward muffler will take some patience. Bolt engine back on being careful not to over tighten bolts. Place steering arm and nut back in place. Thread your belt back through the pulleys and tensioner (make sure your spring is strong enough to tension the belt or buy a new one).

The PTO is "keyed" on the shaft. Replace bolt and washer. Put your deck back on and you're ready to mow again. Give yourself an hour for this one.

HI,
I assume you are reffering to the mower deck pulley...however, the belt that drives the two hydraulic motors work the same way as deck pulley system.
First, there is no manual adjustment on the pulley system. Rather there is a spring loaded pivot arm to which an idle pulley is fastened to. The spring pulls the pivot arm in such a way the it forces the idle pulley to keep the belt tight at all times. The same setup is used on the ground drive belt.
Sometimes these springs become disconnected or break so that no tension is placed on the belt to keep it tight.
Check the tensioner spring to ensure that it is connected properly and applying tension to the belt. Otherwise, you may have the incorrect belt installed, the belt is routed incorrectly or the belt may be stretched out and need replacing.
Here is a diagram to clarify, the spring is the dark black item;




Here is a link to a large diagram that is easier to read;

Lawn Mower Parts Small Engine Parts Much More PartsTree com Briggs MTD...

MOST probably needs a new belt. Or, if you recently replaced belt, it's the wrong size (too long).
Make sure you get right sized belt, and get Kevlar belt - non-Kevlar belts wear out and stretch sooner.

Had the same problem after winter storage and couldn't find an answer anywhere. I noticed that the drive belt (not the ribbed deck belt) was loose when the deck was down below 4 and tight when it was up higher.
That told me either belt is stretched beyond the belt tensioner's or the tensioner wasn't working right. Found that the tensioner was hard to move and would stick. Greased the zerk on top of the large bolt, worked it back and forth a number of times by pulling on the belt. Problem fixed. But I'm thinking it may be time to order a new tensioner spring and belt anyway. Hope this helps someone down the road. If so pass it on. :) jerseyjimmers@yahoo.com

Take the belt and apply axle-grease to it alllll over. apply large amounts of grease to each pully - and then just slide it on.