Stihl HT 101 Telescopic Drive Tube is rotating back and forth instead of staying in fixed position even when clamp screw is tightened?

Hi Little Bird
Chances are that the clutch needs servicing or replacement.
Here's a link that explains:
http://www.lilredbarn.net/Stihl-HT-101-Pole-Pruner-Clutch-s/29554.htm
Cheers

For the 2.5L v6 engine:

Disconnect the negative battery cable. There is a remote negative connection at the left strut tower with an insulator grommet. Place this grommet on the stud to prevent the negative cable from accidentally grounding.
Remove the following: the bolt attaching the air inlet resonator to the intake manifold. Loosen the clamps holding the air cleaner cover to the air cleaner housing. Remove the PCV air hose from the air inlet tube. Loosen the hose clamp at the throttle body.
Remove the air cleaner cover, resonator, and inlet tube. Remove the EGR tube.
Mark for identification and remove the spark plug wires from the distributor cap.
Remove the distributor cap-there are two hold down screws. Mark the rotor position relative to the distributor body. Then remove the rotor.
Unfasten the two electrical connections from the distributor.
Remove the two distributor hold-down nuts and washers. If necessary, remove the spark plug cable mounting bracket.
Remove the transaxle dipstick tube. Then remove the distributor from the engine.
To install: Inspect the distributor's O-ring seal and replace if necessary Carefully engage the distributor drive with the slotted end of the camshaft. Verify rotor alignment with the previously made mark. Reinstall the hold-down nuts and washers and tighten to 9 ft. lbs. Connect everything back in reverse order.

If timing was disturbed while distributor was out: rotate the crankshaft until the #1 piston is at TDC of the compression stroke. Rotate the rotor to the #1 terminal position on the distributor cap. Put the distributor in place, engaging the distributor drive with the drive on the camshaft. With distributor seated, the rotor should be on the #1 terminal. Reinstall the hold-down nuts and washers.

Well, that's all! So much stuff is in the way, it makes it difficult. Post back if you need more help. Good luck.

More information please. Where will the cain not engage in the bar sprocket or on the drive sprocket

http://www.magic-parts.co.uk/acatalog/Stihl-HT-101-Pole-Pruner.php

The water pump can be removed and installed without discharging the air conditioning system (if equipped).

1. Disconnect battery negative cable.
2. Drain cooling system. Refer to Draining and Filling found under Cooling System, Service and Repair.
3. Do not waste reusable coolant. If solution is clean, drain coolant into a clean container for reuse. WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER 6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20) MAY BE USED FOR LARGER CLAMPS. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS. CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with matching number or letter.
4. Remove upper radiator hose clamp and hose at radiator.
5. The thermal viscous fan drive is attached (threaded) to the water pump hub shaft. Remove fan/viscous fan drive assembly from water pump by turning mounting nut counterclockwise as viewed from front. Threads on viscous fan drive are RIGHT HAND. A Snap-On 36 MM Fan Wrench (number SP346 from Snap-On Cummins Diesel Tool Set number 2017DSP) can be used. Place a bar or screwdriver between water pump pulley bolts to prevent pulley from rotating. Do not attempt to remove fan/viscous fan drive assembly from vehicle at this time.
6. 6. If water pump is being replaced, do not unbolt fan blade assembly from thermal viscous fan drive.
7. Remove fan shroud attaching hardware (two bolts at bottom-two clips at top).
8. Remove fan shroud and fan blade/viscous fan drive assembly from vehicle as a complete unit.
9. After removing fan blade/viscous fan drive assembly, do not place thermal viscous fan drive in horizontal position. If stored horizontally, silicone fluid in viscous fan drive could drain into its bearing assembly and contaminate lubricant.
10. Do not remove water pump pulley bolts at this time.
11. Remove accessory drive belt as follows: The drive belt is equipped with a spring loaded automatic tensioner. Relax tension from belt by rotating tensioner clockwise (as viewed from front). When all belt tension has been relaxed, remove accessory drive belt.
12. 12. Remove four water pump pulley-to-water pump hub bolts and remove pulley from vehicle.
13. Remove lower radiator hose clamp and remove lower hose at water pump.
14. Remove heater hose clamp and heater hose from heater hose coolant return tube.
15. Loosen heater hose coolant return tube mounting bolt and remove tube from water pump. Discard the old tube O-ring.
16. Remove seven water pump mounting bolts.
17. Loosen clamp at water pump end of bypass hose. Slip bypass hose from water pump while removing pump from vehicle. Discard old gasket. CAUTION: Do not pry water pump at timing chain case/cover. The machined surfaces may be damaged resulting in leaks.

INSTALLATION

1. Clean gasket mating surfaces.
2. Using a new gasket, install water pump to engine as follows: Guide water pump nipple into bypass hose as pump is being installed. Install water pump bolts. Tighten water pump mounting bolts to 40 Nm (30 ft. lbs.) torque.
3. Position bypass hose clamp to bypass hose.
4. Spin water pump to be sure that pump impeller does not rub against timing chain case/cover.
5. Install a new O-ring to the heater hose coolant return tube. Coat the new O-ring with antifreeze before installation.
6. Install coolant return tube and its mounting bolt to engine. Be sure the slot in tube bracket is bottomed to mounting bolt. This will properly position return tube.
7. Connect radiator lower hose to water pump.
8. Connect heater hose and hose clamp to coolant return tube.
9. Install water pump pulley. Tighten bolts to 27 Nm (20 ft. lbs.) torque. Place a bar or screwdriver between water pump pulley bolts to prevent pulley from rotating.
10. Relax tension from belt tensioner. Install accessory drive belt.
11. CAUTION: When installing the serpentine accessory drive belt, the belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. Refer to Illustration above for correct belt routing. The correct belt with correct length must be used.
12. Position fan shroud and fan blade/viscous fan drive assembly to vehicle as a complete unit.
13. Install fan shroud.
14. Install fan blade/viscous fan drive assembly to water pump shaft.
15. Fill cooling system.
16. Connect battery negative cable.
17. Start and warm the engine. Check for leaks.

Each leg lock has a leg locking lever and a screw that hold the clamp assembly tight to the leg. Unlock the leg lock lever, loosen the screw above it that holds the clamp tight to the leg. The legs should fit into each other sice each leg is slightly larger or smaller then then next one. Slide the clamps in the approprite places and tighten the screw enough to hold the clamp assembly tight, but do not over tighten it. Over tightening will damage the 679 tubes.

The Metal Clamp referenced clamps directly on the end of the '2-Piece Gear Box Assembly'. The gear box assembly is an aluminum casting held together by 3 machine screws. The Metal Clamp does not actually lock the drive shaft housing into the gearbox assembly. The flexible drive shaft cable engages the engine output shaft, and the gear box assembly. This is a fixed length (non-adjustable) assembly.

First ensure that the drive shaft assembly is fully engaged at the quick connect fitting and that the "snap" is engaged. Then make sure the knob is fully tightened. The quick connect allows you to quickly switch between various attachments offered on this unit.

Now, based on your description, it sounds like the 'anti-rotation screw' 791-182519 has backed out or is gone. This will allow the entire cutting assembly (gearbox forward) to slip off of the drive shaft housing and disengage the flexible drive shaft. If your cutting assembly is attempting to rotate while in operation, or the drive is not engaged as you described.
Do not continue to operate the unit until you get this fixed as you could strip out the drive shaft end or cause other serious damage to the equipment or yourself.

If it is the anti-rotation screw, then make sure to push the drive shaft housing firmly into the gear box and ensure to align the holes in the drive shaft housing and the gear box. If the screw is lost, then find one similar sized, but be CERTAIN that it is not too long as it will actually engage the flexible drive shaft and prevent rotation, or cut the drive shaft.

Back to the clamp: If it is still wanting to move, then remove the lock nut and place slightly oversized washers on the bolt head and the lock nut. This will force more pressure (does not take much) on the clamp and will lock it down.

I just fixed mine today (071809) in fact and had to drill a new hole in the drive shaft housing as the original was completely wallowed out.

I hope this helps.

DROPNDEAL

3.0L or 3.8L engine?

please rate as fixed if this solves your issue.

Section 03-01B: Engine, 3.8L 1996 Windstar Workshop Manual
IN-VEHICLE SERVICE Water Pump SPECIAL SERVICE TOOL(S) REQUIRED Description Tool Number Fuel Line Disconnect Tool Set T90T-9550-S
Removal

1. Drain engine cooling system. Refer to Section 03-03 .
   

1. Loosen drive belt tensioner (6B209) and remove drive belt (8620). Refer to Section 03-05 .
   

1. Raise vehicle on hoist. Refer to Section 00-02 .
   

1. Disconnect lower radiator hose (8286) from radiator lower hose tube (8291) and radiator (8005).
   

1. Disconnect radiator lower hose tube from water pump (8501).
   

1. Remove lower nut on both front engine support insulators (6038).
   

1. Lower vehicle.
   

1. Disconnect battery ground cable (14301). Refer to Section 14-01 .
   

1. Remove generator (GEN) (10346) from power steering pump support (3C511).
   

1. Position drain pan and disconnect power steering pressure line from power steering pump (3A674) using Fuel Line Disconnect Tool Set T90T-9550-S.
   

1. Remove power steering reservoir filler cap.
   

1. CAUTION: If using a prying device to assist in water pump removal, be careful not to damage the mating surfaces.
   Disconnect water bypass hose (8597) and oil cooler hose (6B850) from heater water outlet tube (18663).
   

1. Remove retaining bolts and disconnect heater water outlet tube from water pump.
   

1. Remove A/C bracket brace.
   

1. Attach engine lifting eye to left-hand (front) exhaust manifold (9430).
   

1. Attach lifting equipment to engine lifting eye and raise front of engine approximately 51 mm (2.0 inches) to provide necessary clearance for water pump removal.
   

1. Remove water pump pulley retaining bolts and water pump pulley (8509).
   

1. Remove drive belt tensioner pulley retaining bolt and drive belt tensioner pulley (6B217) from power steering pump support.
   

1. Remove power steering pump support retaining bolts and nut. Place power steering pump and support assembly aside in a position to prevent fluid leakage.
   

1. Remove water pump retaining bolts and nuts and water pump. Discard used water pump housing gasket (8507).
   

Installation

1. NOTE: Lightly oil all bolt and stud bolt threads before installation except those specifying special sealant.
   
   Clean gasket surfaces on water pump and engine front cover (6019).
   

1. NOTE: The threads of the No. 1 engine front cover retaining stud must be coated with Pipe Sealant with Teflon® D8AZ-19554-A or equivalent meeting Ford specification WSK-M2G350-A2 before installing.
   
   NOTE: Gasket and Trim Adhesive D7AZ-19B508-B or equivalent meeting Ford specification ESE-M2G52-A is recommended to hold the water pump housing gasket in position.
   
   Position a new water pump housing gasket on water pump housing sealing surface.
   

1. Position water pump on the engine front cover. Install retaining bolts.
   

1. Position power steering pump support and install retaining nuts and bolts. Tighten bolts and nuts to 40-55 Nm (30-40 lb-ft).
   

1. Install drive belt tensioner pulley and retaining bolt. Tighten bolt to 70-95 Nm (52-70 lb-ft).
   

1. Install A/C bracket brace.
   

1. Position water pump pulley on water pump hub and install retaining bolts. Tighten bolts to 8.0-11.5 Nm (71-101 lb-in).
   

1. Lower engine and disconnect lifting equipment from lifting eye.
   

1. Remove lifting eye from exhaust manifold.
   

1. Connect heater water outlet tube to water pump and install retaining bolts. Tighten bolts to 8-11.5 Nm (71-101 lb-in).
   

1. Connect water bypass hose and oil cooler hose to heater water outlet tube. Tighten clamps securely.
   

1. Connect power steering pressure line to power steering pump fitting.
   

1. Install power steering reservoir filler cap.
   

1. Install generator to power steering pump support. Refer to Section 14-02 .
   

1. Connect battery ground cable. Refer to Section 14-01 .
   

1. Raise vehicle on hoist. Refer to Section 00-02 .
   

1. Install lower nut on front engine support insulators and tighten retaining nut to 88-119 Nm (65-87 lb-ft). Install lower nut of rear engine support insulator and tighten to 77-104 Nm (56-76 lb-ft).
   

1. Connect radiator lower hose tube to water pump. Install retaining bolt and tighten securely.
   

1. Connect lower radiator hose to radiator lower hose tube and radiator. Position hose clamps securely. Refer to Section 03-03 .
   

1. Lower vehicle.
   

1. Position drive belt over drive belt tensioner and release drive belt tensioner. Refer to Section 03-05 .
   

1. CAUTION: This engine has aluminum cylinder heads (6049) and requires a special corrosion inhibiting coolant to avoid cooling system damage. Refer to Section 03-03 for the coolant specifications.
   Fill and bleed cooling system with specified coolant.
   

1. Fill power steering pump reservoir with specified fluid.
   

1. Start engine and check for coolant and power steering fluid leaks. Service as necessary.
   
   
   Water Pump
   

Does it move at all??? If so then the star bolt that goes in the center hole is the brake so to speak.
the lever that turns back and forth on the column has 2 small screws that attach to the lever.
tighten the center bolt until the wheel is secure, then set the tightening lever to the tight position and put the 2 screws in place. they will fit in between the star or teeth on the bolt and attach to the tightening lever.