Clutch pedal adjustment?

[FiremarshalBill49]

When shifting the 4-speed on my 72' (L-16) 620, I need to push the clutch pedal hard against the firewall floor to make a smooth shift.  Is there an adjustment I can make to the pedal travel so that the clutch pedal engages the engine maybe an inch from the floor rather than pressed hard against the floor? Thanks

[datzenmike]

Well first check that there is about 1/16" (about 2-3mm) of pedal clearance by pushing down on the clutch with your thumb. It should move freely and then become much stiffer over about 1/16"

 

 

Your clutch master cylinder beside the brake booster may have run out of hydraulic fluid.

 

If that checks out ok you probably have some air trapped in the hydraulic system. There is a bleeder screw on the slave cylinder on the front right side of the transmission. Press down on the pedal and loosen the bleeder and let out any fluid and air bubbles. Hold the clutch down and tighten the bleeder then repeat. Pedal down and hold, loosen bleeder, let out fluid, tighten bleeder, let pedal up and repeat. At no time let the reservoir run dry when doing this so get help. 5 or 6 repetitions should fix this. 

[banzai510(hainz)]

after you do the above ck and bleed you can adjust the threaded rod also. I believe they are 12mm. jam nut and a half moon which pushes the clutchfork. Here is where you want that 1/16 play. so you dont wear ou the Throw Out bearing

[datzenmike]

Hainz, the 620 ('73 FSM) does not use the adjustable push rod. That stopped with the 521 the 510 and the early 610 at least. The 710 is supposed to have one but my '76 didn't.

[flatcat19]

My 71 521 had a fix push rod. No adjustment. All one piece to the cylinder.

 

When I replaced the master, I removed this rod and installed to new. No issue.

 

 

Follow above instructions. Check back side of master, in cab, to see if there is fluid seepage. Pull back boot on slave to check for leaking there too.

 

Have someone hold pedal and check rubber hose going in to slave. See if hose sweats or bulges.

[Stoffregen Motorsports]

Hainz, the 620 ('73 FSM) does not use the adjustable push rod. That stopped with the 521 the 510 and the early 610 at least. The 710 is supposed to have one but my '76 didn't.

True, but many parts have found their way onto other vehicles over the years. I used to buy the adjustable slaves and install them on vehicles that came with non-adjustable slaves.

[banzai510(hainz)]

I wasn't sure the on the 72s as my 521 is listed as a 72.

I like the adjustable  slave rods anyway and have it on my 200sx 5 speed so I use a 71 510 fork,71  slave cylinder with threaded rod.

 

order whatever your year vehicler requires.  as a 200sx rod is non treaded and shorter but the clutch diaphrame height for a 200sx is different than a 510 even dough they both are 200mm clutches.