Clutch, Synchros, or Normal?
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Joined: Aug 2003
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From: Nowthen MN
Clutch, Synchros, or Normal?
I have an 88 4+3 that has two issues:
#1 a heavy clutch pedal
#2 I have to shift into first and let out the clutch slightly before shifting into reverse or else it grinds
I read somewhere (I thought it was the C4 source book) that both of these things are normal for this vintage of car, but if they aren't normal I want to fix them before they cause a problem.
If they are normal, is there any way to remedy them?
Best Regards,
-J
#1 a heavy clutch pedal
#2 I have to shift into first and let out the clutch slightly before shifting into reverse or else it grinds
I read somewhere (I thought it was the C4 source book) that both of these things are normal for this vintage of car, but if they aren't normal I want to fix them before they cause a problem.
If they are normal, is there any way to remedy them?
Best Regards,
-J
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Joined: Jun 2008
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It's been a long time since I had a standard, however I remember a couple of things.
First of all, reverse isn't synchronized, so it has the propensity to grind.
What you're doing by shifting into another gear before reversing is stopping the gear train inside the transmission from turning. You can shift into the forward gears without grind because they are synchronized. It's possible the clutch isn't fully disengaging, or the flywheel is warped. This allows the input shaft to start moving as you are in the act of selecting reverse, or tend to keep moving if you were idling in neutral with the clutch out.
If this continues it will eventually put a hurting on your first gear synchro.
First of all, reverse isn't synchronized, so it has the propensity to grind.
What you're doing by shifting into another gear before reversing is stopping the gear train inside the transmission from turning. You can shift into the forward gears without grind because they are synchronized. It's possible the clutch isn't fully disengaging, or the flywheel is warped. This allows the input shaft to start moving as you are in the act of selecting reverse, or tend to keep moving if you were idling in neutral with the clutch out.
If this continues it will eventually put a hurting on your first gear synchro.
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Joined: Aug 2003
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From: Nowthen MN
It only grinds into reverse when I come to a complete stop and shift directly into reverse. Are there any tests that one can do to verify the problems that you mentioned?
I'm looking to throw some money at my car this fall and would prefer to buy a new cam and some other goodies, but I don't want to have a bad clutch rear its ugly head. I had a clutch explode on another car once and that was a bummer.
Thank you,
-J
I'm looking to throw some money at my car this fall and would prefer to buy a new cam and some other goodies, but I don't want to have a bad clutch rear its ugly head. I had a clutch explode on another car once and that was a bummer.
Thank you,
-J
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Joined: Mar 2008
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From: High Bridge New Jersey
If
I have an 88 4+3 that has two issues:
#1 a heavy clutch pedal
#2 I have to shift into first and let out the clutch slightly before shifting into reverse or else it grinds
I read somewhere (I thought it was the C4 source book) that both of these things are normal for this vintage of car, but if they aren't normal I want to fix them before they cause a problem.
If they are normal, is there any way to remedy them?
Best Regards,
-J
#1 a heavy clutch pedal
#2 I have to shift into first and let out the clutch slightly before shifting into reverse or else it grinds
I read somewhere (I thought it was the C4 source book) that both of these things are normal for this vintage of car, but if they aren't normal I want to fix them before they cause a problem.
If they are normal, is there any way to remedy them?
Best Regards,
-J
The heavy pedal shouldn't have anything to do with the wear of the clutch.
Drifting
Joined: Feb 2003
Posts: 1,978
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From: San Antonio Texas
The first thing I would do is to "Bleed" the Clutch Cylinders. If it isn't done correctly, it will give problems like you mentioned. It sounds like the Master and/or the Slave Cylinder might be going bad though.
Drifting
Joined: Oct 2006
Posts: 1,328
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From: Stafford Connecticut
I have an 86 with 4-3 trans.My factory owners manual says to put the trans in a forward gear before you put the trans in reverse so as to prevent grinding.What you are describing is normal for most stick shift trans.
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From: High Bridge New Jersey
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From: Nowthen MN
@Steven Mack - I knew I had read it somewhere, just couldn't place it. How heavy is your clutch pedal?
@Curveit - I replaced the master, slave, and hose between the two back in 2003 to try to help with the clutch effort issue, I had it bled by the local corvette shop because I couldn't get all of the air out of the system otherwise. Nothing changed once it was all said and done.
Thanks Guys!
-J
@Curveit - I replaced the master, slave, and hose between the two back in 2003 to try to help with the clutch effort issue, I had it bled by the local corvette shop because I couldn't get all of the air out of the system otherwise. Nothing changed once it was all said and done.
Thanks Guys!
-J
Drifting
Joined: Oct 2006
Posts: 1,328
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From: Stafford Connecticut
My clutch pedal effort is heavy.And yes Aurora the factory owners manual does say put the trans in a forward gear before putting the trans in reverse.It states specifically engagement of a forward gear,prior to engaging reverse will help avoid reverse gear clash.Page 2-9.As far as the newer 6 spd it's still a good idea to do the same.I have had many manual transmissions trucks cars you name it and have found this method useful to avoid reverse gear grind.
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
As already explained, reverse has no syncros and if in neutral and pushing in the clutch, you shift quickly into reverse, you will experience grinding and this is normal. If you suspect your clutch is doing something odd (I say this because it must be disengaging if you can shift from a forward gear into reverse without grinding) then while in neutral, push the clutch in and wait a full minute (provides time for the cluster gears to coast to a stop) and then shift into reverse. You should not experience grinding. If you do, your clutch may not be fully disengaging.
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
When I first got my 87 with a 4+3, the clutch seemed to be working fine but I had the same symptoms; hard to get into reverse without grinding. The car also got to where it was hard to engage 1st. It wouln't grind but it was physically hard to move the shifter into 1st.
I replaced the clutch and when the old disc came out, it was toast. With a new clutch and pressure plate installed, the grinding went away.
The clutch hydraulic linkage is not adjustable, in my case, I tried to bleed the hydraulics but it didn't help.
As far as a "heavy" pedal, it may be that the pressure plate is a HD unit and that would increase the force needed to depress the pedal.
I replaced the clutch and when the old disc came out, it was toast. With a new clutch and pressure plate installed, the grinding went away.
The clutch hydraulic linkage is not adjustable, in my case, I tried to bleed the hydraulics but it didn't help.
As far as a "heavy" pedal, it may be that the pressure plate is a HD unit and that would increase the force needed to depress the pedal.
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Joined: Aug 2003
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From: Nowthen MN
I believe that the clutch is not fully disengaging. While moving at about 55 mph O/D engaged, I push in the clutch pedal and disengage the O/D and I feel a slight clunk.
Another thing is that with the car off, the shifter can't be moved into reverse until the clutch pedal is depressed sometimes.
Sounds like it's time for a new clutch.
-J
Another thing is that with the car off, the shifter can't be moved into reverse until the clutch pedal is depressed sometimes.
Sounds like it's time for a new clutch.
-J
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
I believe that the clutch is not fully disengaging. While moving at about 55 mph O/D engaged, I push in the clutch pedal and disengage the O/D and I feel a slight clunk.
Another thing is that with the car off, the shifter can't be moved into reverse until the clutch pedal is depressed sometimes.
Sounds like it's time for a new clutch.
-J
Another thing is that with the car off, the shifter can't be moved into reverse until the clutch pedal is depressed sometimes.
Sounds like it's time for a new clutch.
-J