Jump to content
SAU Community

Recommended Posts

Hi all. As topic states.

Car: R32 gtst RB20DET.. stock clutch, gearbox etc.

Problem: Shifting is not a problem. However, when i quickly clutch in and put it to first (when the car is stationary) it sometimes crunches.. though the frequency is getting alot higher.

To be safe, I have to slowly step on the clutch ALL the way down to the bottom. AND THEN and only then can I engage first gear.

It happens in situations for example: When your sitting at the lights and then all of a sudden the lights change to green. I quickly try to gear in to first and it crunches. It slowly eats a little of my heart out each time i hear/feel it crunch my gears.

What could it be?

Thanks in advance, Ben.

Link to comment
https://www.sau.com.au/forums/topic/183796-crunching-first-gear/
Share on other sites

I was thinking it was more to do with the clutch.. because when i clutch in first then engage the gear it feels like the clutch hasnt fully engaged yet.

I've had previous problems with my clutch before. Last time the slave cylinder blew and when i got it replaced, the mechanic didnt bleed it in properly and it was slipping like hell.. he sorted that out.. but yeah..

maybe bubbles in my clutch line?

from what ive read, first gear doesnt have syncro's (hence you cant shift into it whilst rolling, unless you rev-match)

My one acts similar, it doesnt slide into 1st gear when stationary, i feel a resistance, notchy but no actual grinding.

I'll be replacing my clutch in a couple weeks time, so can comment then if i have a change in shifting etc

well yeah.. that kinda doesn't really solve my problem.

My problem now is crunching when quickly gearing into first: at times for example when i'm at the lights and it suddenly goes green. If I gear in slowly i.e. clutch in all the way to the bottom (slowly) then engage first theres usually no problem.

From what I feel, it feels as though when i quickly step on the clutch pedal, the actually mechanisms (after the clutch pedal) are laggy in engaging the clutch. like the clutch itself has a slower reaction time into actually engaging.. For example if you were to as quickly as possible step on the clutch pedal. I.e. STAMP on it and then chuck it into first gear it will definitely crunch. Which brings me to question whether or not there are bubbles in my clutch lines/reservoir.

How can you check for bubbles? I've tried getting someone to pump the clutch while i open the lid of the reservoir and see if theres any bubbles or anything.. (no avail)

Blah.. hard to explain i guess.. if i figure this out i'll post up a proper explanation/solution.

Edited by chinkeboi
from what ive read, first gear doesnt have syncro's (hence you cant shift into it whilst rolling, unless you rev-match)
Since when ????

Not since 1970s. My family's 1968 Falcon had synchro on first.

chinkeboi, why don't you keep an eye on the lights so you can be in first gear when they change?

Since when ????

Not since 1970s. My family's 1968 Falcon had synchro on first.

chinkeboi, why don't you keep an eye on the lights so you can be in first gear when they change?

Lol.. thats not really the point man, however bliss ignorance is.. something is wrong with the car and i want to try and ATLEAST source the problem. as for me being alert at the lights thats no problems..

I'm getting the gearbox oil changed next service and i'll let u know if that helps or not

give the clutch fluid a good flushing. and dont slam it into gear :S even if the light goes green, only takes a extra 1-2seconds to wait for the clutch to engage... or upgrade ur clutch and pressure plate so it grabs sooner/faster/harder....

I found this, hope it may help;

===================================================

Service Information - Bulletin Number 23 01 99

SUBJECT: Manual Transmission Difficult to Shift - Diagnostic Tips

MODEL: All with Manual Transmission

SITUATION: Transmission may be difficult to shift especially first gear

engagement and/or gear shift linkage is binding. Note: Field observations

have indicated that a transmission which is difficult to shift (especially

into first gear) is primarily a clutch related problem and only in isolated

cases a failure in the transmission itself.

PROCEDURE:

Verify the customer complaint:

Note: Engage the parking brake and assure that no people or objects are in

the vehicle's path.

- - Run the engine at idle speed

- - Press the clutch pedal to the floor

- - From the neutral stick shift position engage first gear

If first gear is difficult to engage, hold the stick shift at the

resistance point (approximately half of the total stick shift travel) with

constant force.

Then switch the ignition off with the other hand.

DIAGNOSIS 1:

If first gear now engages completely, i.e. the stick shift moves to the end

position without any additional pressure applied, there is a problem in the

clutch system.

Explanation:

Because the clutch does not uncouple completely, a residual torque is

transmitted to the transmission input shaft when the engine is running.

This inhibits the release and meshing of the sliding sleeve, in the

transmission, at the end of the synchronization process. Turning the

engine off relieves the input shaft of this torque thus simulating a

completely uncoupled clutch.

DIAGNOSIS 2:

If the stick shift remains at the resistance point, there is a problem in

the external gear shift linkage or in the transmission.

CAUSE:

DIAGNOSIS 1:

Possible causes for a clutch problem as per Diagnosis 1 above are:

- - Input shaft taper splines not lubricated properly/grease dried out.

- - Clutch disc difficult to move on transmission input shaft.

- - Clutch disc wobble.

- - Air in the hydraulic system of clutch mechanism.

- - Release bearing defective or difficult to move on the guide sleeve.

- - Clutch disc or pressure plate broken/worn out.

DIAGNOSIS 2:

Possible causes for gear shift linkage binding and/or internal transmission

problems as per Diagnosis 2 above:

- - External gearshift linkage binding (shift rod joints stiff).

- - Stick shift bellows boot incorrectly installed (positioned too high or

too low on the stick shift lever).

- - Sound deadening between the outer gear shift linkage and the body

incorrectly installed and/or distorted.

Possible causes inside of the transmission:

- - Faulty synchronization.

- - Internal gear shift linkage binding.

- - Water in the transmission fluid. (rare)

===================================================================

yeah. if it does it when its not moving then yes. its a clutch issue. and now its f**ked the synchro and selector sleeve on 1st. so you will have to just put up with it till you get a new clutch.

you do let it rest for a few seconds before you put it in gear? if not thats relativly normal if you just foot on clutch and bang it in gear.

if you put your ear on the shifer while its running you can here it spinning. put the clutch in and you should hear it slow down and stop. that time is how long you should wait till you put it in gear to avoid crunching

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I don’t really have any ideas how to set the timing on the CAS 😂, sounds like the top, sounds like it maybe misfiring as well as ticking,  got the box sorted 😌, must of been a air bubble on the clutch side
    • Use a 2' length of hose (that's 2 foot, not 2 inches) as a stethoscope to localise the source of the ticking. From cam covers? From exhaust or turbo manifold gasket? From injectors? From lower down in the engine? Etc. Use a timing light to set the timing. Put Redline Lightweight Shockproof in the box. It's not the very best thing for the box, but it will take a box that refuses to engage a gear with other oil, and make it engage a gear. I had to put it in when I installed the R33 box I have in my car. It would not select ANY gear when running. Smurf jizz made it work. That was >10 years ago and I still use it. I'm stuck with it now. Failing that - rebuild the box.
    • Well done Duncan. The fuel tank bulkhead lid is also in great condition (some of mine were stuffed). These are now out of production and good ones like that are becoming hard to come by.
    • Wow that's a steal, you've done well there. 
    • Exterior LEDs R34 2Dr R34 4Dr Position Lamp T10 T10 Winker front T20S T20S side T10 T10 rear T20S S25S150 Anti-hyfla relay TYPE3 TYPE3 tail T10 T20W Stop Lamps T20W T20W High Mount T16 T16 back T16 T20S number T10 T10 trunk T10 T10 Interior LED Item No.     Map Lamp BA9S single-sided     Room Lamps T10×31     Trunk Lamp T10     meter Early T6.5 pedestal     final T6.5 pedestal     NISMO T6.5 pedestal     Liquid crystal section T6.5 pedestal     Winker T6.5 pedestal     High Beam T6.5 pedestal     3 SERIES METER Early T6.5 pedestal     final T6.5 pedestal     NISMO T6.5 pedestal     air conditioner Early Liquid Crystal T3     Late LCD T4.2 Short     button T4.2 Middle     Hazard SW T3 Pedestal Short     Keyring T5     Cigar Socket T5
×
×
  • Create New...