Z150 and Z1 FR Service Manual

It seems that for the past two years ('03 and '04) Marzocchi have decided not to publish the service manuals for their forks. Probably because they can make more money by offering to do the service themselves. Since they don't publish one, i thought i would give it a go. I'm reasonable technically minded so know what i should be doing or not. Luckily it was very simple and not many tools were required! I took a few photos to add to it, though not many as i didn't really want to get fork oil all over my camera.

The service was done on a pair of 2003.5 Z150's which i believe are just about the same as the Z1 Freeride fork.

Following the bellow instructions is totally at your own risk. I hold no responsibility for any damage caused to the forks or bike they are attached too and any injury/death that may be cause as a result of the following instructions. This sucks but i have to say this, American's might be reading it :-p

Tools

- 21mm socket

- 12mm socket (a long narrow one, see below)

- Ratchet (or other tool to attach the sockets)

- 10mm open ended spanner

- Fresh 7.5wt oil around 500ml ideally (see below)

- A load of old news papers for the area you're working. It'll get messy!

- Container for the old oil

- A cloth of some sort to clean the forks down. I used kitchen roll.

Process

Remove the forks from the bike and clean the outer bits up a little, you don't want any mud falling inside the internals. Remove any air preload if there was any in there.

Using the 21mm socket un-do the top cap on the HSCV leg (right hand leg rider perspective, with the rebound adjuster on). Turn the ETA dial to lock the fork out and compress it as much as you can

Just below the top cap there will be a red 10mm nut. This is fixed to the damper shaft and is used to tighten the top cap to the damper (basically it holds the top of the fork to the bottom so be careful with it!). With the 21mm socket on the top cap still undo the red 10mm nut clockwise (as if you were looking down on the top cap) hold the 21mm socket in place. It may feel stiff occasionally (not sure why but mine did) don't let this put you off putting some force on it. Keep unscrewing turning it until the top cap can be removed from the damper.

Lift the spring out of the fork at the same time (yellow spring) along with a round washer that is on top of the spring.

Tip the fork upside down over a container of some kind to catch the oil. Quite a lot will come out, cycle the damper shaft quite a few times, fast and slow to make sure as much as the oil comes out of the fork.

Once all the oil is out of the HSCV damper leg switch the dial on the ETA leg to allow the forks to rebound. You will have to remove the ETA knob attachment is it hasn't already broken off ;-) to get the 21mm socket onto the top cap. Again, undo this cap and compress the uppers (the springs won't be trying to rebound the forks now). Find the red 10mm nut and undo as on the HSCV leg and remove the spring (slightly shorter red one).

Tip the fork upside down once again to remove all the oil. Cycle the ETA damper shaft up and down as in the HSCV leg to make sure as much oil as possible comes out of the fork. The ETA damper may feel really stiff to cycle up and down, there appears to be loads of stickshion (is that really a word?) in it (feels a bit sticky to get moving).

Once all the oil has been removed you can undo the 12mm foot nuts at the base of the fork. Undo the foot nut bolts the usual way (anti-clockwise) if looking at the base of the fork from the bottom. They may appear to slip a little bit, this is because the damper is rotating, try holding it still from the top of the fork. It will undo.

Once the foot nuts are un-done put them in a safe place along with the top caps etc you can now remove the stanchions from the lowers. They'll just slide out nicely. Remove the little circular springs around the dust seals on the lowers and put them with the foot nuts and top caps. The dampers will probably be left in the lowers if the forks were up right while removing the stanchions. Take both dampers out and put them somewhere safe in some news paper (oil will still be in them and they will leak a little). NOTE: feel the weight difference between the uppers and the lowers!

Now, start cleaning the insides of the uppers and lowers, try to get as much as the old oil out as possible. The old oil will contain bits of the bushings (as they wear and bed-in bits will rub off) and i found a few pieces of the powder coating from the springs in there! Once they are totally clean and oil free place them to one side.

Take the ETA damper shaft. These are sealed units so you can't open them and please don't attempt to! Cycle both up and down to remove as much oil as possible leave up-right (the same orientation as it came out of the fork) to allow any oil to drain out.

Once you are satisfied that as much oil is out of the dampers as possible take the HSCV damper and unscrew the external rebound adjuster anti-clockwise (as if you were decreasing the rebound damping or speeding up the fork). Lift if out of the damper shaft. CAUTION! the rebound adjuster is a very thin rod with looks rather fragile so handle it with care.

Clean up both that damper shafts well to remove any surface oil. Leave the rebound adjuster rod out of the HSCV leg for now.

Find some high quality grease, i find that Manitou M-Prep, Pace, Fineness, Finish Line and Rock 'N' Roll produce some great grease for forks. Put a small amount in between the dust seals (outer most seals around the stanchions) and the inner oil seals. Place it where it will come into contact with that stanchions but not so it will mix with the oil in the lowers.

Now once you are satisfied that everything is clinically clean you can start to put it all back together. Firstly slide the stanchions back into the lowers, don't forget to put the little circular springs that fit around the dust seals onto the stanchion before putting them into the lowers. If you forget you'll have to take them apart again! Make sure the dust seals don't fold under the stanchions, it may damage them.

Slide the stanchions right into the lowers, as far as they will go down. Place the damper cartridges back into the correct legs (ETA leg into the left leg and the HSCV into the right rider perspective). Put the foot nuts back onto the bolts at the base of the lowers. Tighten to the same torque as they were when removed (i don't know the actual value).

Start to fill the forks with shock oil, do it very slowly to stop any air getting trapped in the dampers. Fill the forks when they are fully compressed. Cycle the dampers up and down several times slowly to make sure there is no trapped air. Trapped air will cause a lack of oil and possible loss of damping which could be dangerous while riding. Fill both legs with oil till the oil height is 70mm below the top of the stanchion (top of the treads where the top cap screws in is the best indication).

Carefully fill the HSCV damper through the hole where the rebound adjuster came from. Very little oil will be needed. Make sure the damper is fully extended. Place the rebound adjuster back into its hole and allow is to sink down on its own. This will avoid any air getting trapped. Very carefully screw the adjuster back into place, leave about half a millimeter of screw thread showing. CAUTION! make sure the thread is screwed in properly and not cross threaded as it is a very fine thread. Therefore easily damaged!

Cycle the HSCV damper several times to make sure no air is trapped again. Do whatever you think will get any possible trapped air out of the damper.

Place the shorter (possibly red) spring onto the ETA damper, place the washer on top of the spring and start to screw the top cap back onto the top of the damper shaft. Using the 10mm spanner on the nut and the 21mm socket on the top cap screw the top cap back onto the damper. CAUTION! make sure it is done up tight as it hold the forks together!

Fit the spring and top cap to the HSCV leg, as the ETA leg. Once both fitted correctly, use the 21mm socket to screw the top caps back into the crown/stanchions to the correct torque (again, i don't know the correct value). CAUTION! i've been informed that the top cap threads are a bit cheese like (i.e. they'll strip pretty easily) so carefully make sure the threads engage with each other correctly by hand. If a lot of resistance is felt then unscrew the cap and try again.

Attach all the ETA knobs etc and stick the forks back on your bike.

Check the forks over to make sure they aren't rocking or anything and that the uppers and lowers are firmly attached together.

GO RIDE and be amazed at the smoothness of the forks...

12mm Socket

The official Marzocchi socket tool is very hard to find in the UK, the one i bought was to remove something out of a Mazda! Even then, the outer diameter was too large to fit into the very tight recess where the foot nut is. I spent a while grinding it down with a Dremel electric tool, its a good fit now and I've saved myself about £30 by doing that (i could only find the official one online for USD$25 + USD$40 postage. Then there's import duty and VAT on that!). If you can find a tool that fits without all the grinding then please email me to say where you got it from and i can post it up on here.

Oil

I used Motorex (Oil of Switzerland) 5-10wt fork oil. It may seem a little general but my forks have never worked better. They feel much plusher and there is a noticeable increase in damping adjustment.

Again, following the above instructions is totally at your own risk. I hold no responsibility for any damage caused to the forks or bike they are attached too and any injury/death that may be cause as a result of the above instructions. This sucks but i have to say this, American's might be reading it :-p