how to adjust a h-body clutch

Best technical articles on the forums. Send nominations to the admins. You can reply to topics but only admins can make new ones.

Moderator: Moderators

how to adjust a h-body clutch

Postby peterpan » Thu Dec 13, 2007 2:59 am

scaned this for others to use
You do not have the required permissions to view the files attached to this post.
second star to the right strait on till morning
User avatar
peterpan
 
Posts: 1786
Joined: Mon Jun 26, 2006 11:51 pm
Location: rock springs wyoming

1972 Chevrolet Vega


Postby marco_1978_spyder » Sat Dec 29, 2007 7:33 am

Thanks for posting that, great info.

There's also the ball stud adjustment procedure for the clutch fork.

That can make the pedal alot more comfortable, and less strain on the firewall.
1978 Monza Spyder V8 4speed, posi
1978 Sunbird Formula V6, 5 Speed, Hatchback
1978 Sunbird notchback 4cyl Auto
2006 Chevrolet Aveo 5 speed Hatchback
Yes, you can refer to me as Mark
Please visit my blog... http://chevymonza.blogspot.com/ Follow if you like!
Featuring special guests; Carl Beraytor and Ray D'atore

My Red spyder now has a youtube channel please Like and Subscribe!!!
https://www.youtube.com/channel/UCOzzSR ... ISuing7KLA
User avatar
marco_1978_spyder
Senior Moderator
 
Posts: 5242
Joined: Sun Jun 25, 2006 5:20 pm
Location: Western, New YorK / Rochester

Postby 73astregt » Sat Dec 29, 2007 1:18 pm

hey guys are the clutch cables the same from v6 to v8? i was given a listing on ebay for cables but it says for 231 v6 help guys! these are a hell of a good deal im gonna buy more than one if theyll fit the v8 monza sunbird setup cables are 8.00 each buy it now!
73 astre gt 355 small block 435 hp 435 torque edelbrock performer rpm power package
User avatar
73astregt
 
Posts: 2216
Joined: Sun Aug 12, 2007 4:50 pm
Location: Bridgewater Nova Scotia Canada

1973 Pontiac Astre GT

Re: how to adjust a h-body clutch

Postby 73astregt » Sun Mar 15, 2009 12:49 am

moderators, please put this topic in best of thanks!
73 astre gt 355 small block 435 hp 435 torque edelbrock performer rpm power package
User avatar
73astregt
 
Posts: 2216
Joined: Sun Aug 12, 2007 4:50 pm
Location: Bridgewater Nova Scotia Canada

1973 Pontiac Astre GT

Re: how to adjust a h-body clutch

Postby marco_1978_spyder » Sun Mar 15, 2009 9:30 am

Topic Moved.
1978 Monza Spyder V8 4speed, posi
1978 Sunbird Formula V6, 5 Speed, Hatchback
1978 Sunbird notchback 4cyl Auto
2006 Chevrolet Aveo 5 speed Hatchback
Yes, you can refer to me as Mark
Please visit my blog... http://chevymonza.blogspot.com/ Follow if you like!
Featuring special guests; Carl Beraytor and Ray D'atore

My Red spyder now has a youtube channel please Like and Subscribe!!!
https://www.youtube.com/channel/UCOzzSR ... ISuing7KLA
User avatar
marco_1978_spyder
Senior Moderator
 
Posts: 5242
Joined: Sun Jun 25, 2006 5:20 pm
Location: Western, New YorK / Rochester

Re: how to adjust a h-body clutch

Postby 73astregt » Sun Mar 15, 2009 9:30 pm

thanks marco!
User avatar
73astregt
 
Posts: 2216
Joined: Sun Aug 12, 2007 4:50 pm
Location: Bridgewater Nova Scotia Canada

1973 Pontiac Astre GT

Re:

Postby GrandPa » Sun May 10, 2009 2:25 am

[quote="marco_1978_spyder"]Thanks for posting that, great info.

There's also the ball stud adjustment procedure for the clutch fork.

That can make the pedal alot more comfortable, and less strain on the firewall.[/quote]

Anybody got details, I've got a '79 starfire GT with a hole in the firewall and a left roundhouse that'd make chuck norris proud.
GrandPa
 
Posts: 0
Joined: Sat May 09, 2009 2:30 pm

Re: how to adjust a h-body clutch

Postby spencerforhire » Sun May 10, 2009 7:10 am

Not to nit-pick, but this is the clutch CABLE adjustment; Marco mentioned the ball stud which is actually how the clutch release gap must be adjusted. Often, you have to go back and forth between the 2 to get a clutch dialed in properly.
User avatar
spencerforhire
 
Posts: 2364
Joined: Mon Jul 03, 2006 9:02 pm
Location: Halifax, Nova Scotia

1972 Chevrolet Vega Hatchback

Re: how to adjust a h-body clutch

Postby cjbiagi » Sun May 10, 2009 8:13 am

You are correct, it's a combination of two adjustments. Here is a repost of how I adjust the ball stud and cable. I have been speaking with Dave English about using the GM tool to adjust the ball stud but after thinking and looking at the adjustment with this tool I believe this approach will accomplish the same result.

Ok, here goes. What many people do on these cars is mistakenly adjust the nut on the end of the cable to get there pedal freeplay. This happens because some people don't even know about the clutch ball pivot on the top right side of the bellhousing.
What you want to do is make sure that the clutch fork is pulled all the way to the rear of the car. The return spring should accomplish this, but just make sure it is all the way back. Now you want to adjust the cable by turning the nut at the clutch fork to remove all the slack. You must also make sure that the pedal is all the way up, it helps to have someone pull the pedal up against the rubber bump stop while you adjust the nut to remove any slack in the cable. What you are trying to accomplish is, clutch fork all the way back, pedal all the way up, no slack in the cable. Once this is done now you can adjust the pivot ball on top of the bellhousing. The best way to do it is to actually measure the gap between the clutch disc and the flywheel when the pedal is depressed to the floor. For a diaphram clutch you should have about .030. The only problem is there is no easy way to measure this without an inspection hole in the bottom of the bellhousing. I drilled a small hole in mine, big enough to insert my feeler gauge. It has to be drilled at the point where the disc mates with the flywheel. At this point you loosen the large locknut on the adjusting screw and turn the pivot ball to get the proper gap with the pedal depressed, then lock down the locknut. Since most folks don't have any way of measuring this gap, the more common method of adjusting the pivot ball to result in 1" of pedal freelplay will also work fine. The important thing to remember is that you want the freeplay to be the result of a gap between the throwout bearing and the pressure plate fingers. Having freeplay as a result of a loose cable is not what you want. That's why you want to make sure that there is no slack in the cable to throw off your freeplay measurement. With no slack in the cable, the clutch fork will begin moving immediately when you start to depress the pedal. The clutch fork and throwout bearing will also begin to move immediately, taking up the small gap between the throwout bearing and pressure plate fingers (which gives you your pedal freeplay) and all will work fine. With the cable and pivot ball properly adjusted the throwout bearing will not be in contact with the pressure plate once the pedal is up and there will be no chance of clutch slippage since the pressure plate will be allowed to fully engage. You can fine tune the stud to suit your preference but this puts you very close to where it should be. The important thing is to not have any slack in the cable when you are done, that is just wasted motion and it does not accomplish freeplay where you need it. Different brands of pressure plates and throwout bearings will effect where the stud needs to be. Some clutch assemblies are a little thicker and not all "short" throwout bearings are the same length. Hope this makes sense, if not ask me again!
*** I am adding this simple step by step process which summarizes the above.

1) Have someone pull the clutch pedal against the rubber bump stop.
2) pull clutch fork all the way toward the rear of the bellhousing
3) adjust cable nut to remove any slack
4) Loosen nut on pivot ball stud
5) adjust pivot stud to obtain 3/4" - 1" freeplay at clutch pedal.
6) recheck cable to make sure there is no slack

Clyde
User avatar
cjbiagi
 
Posts: 7973
Joined: Sun Jun 25, 2006 2:37 pm
Location: Glenwood, Illinois

1975 Chevrolet Monza

Re: how to adjust a h-body clutch

Postby jetman » Thu Dec 16, 2010 6:50 pm

[quote="spencerforhire"]Not to nit-pick, but this is the clutch CABLE adjustment; Marco mentioned the ball stud which is actually how the clutch release gap must be adjusted. Often, you have to go back and forth between the 2 to get a clutch dialed in properly.[/quote]
I have a 1975 Monza and it has a half round " pot metal " pulley that the cable goes around. It doesn't look like the pic.
jetman
 
Posts: 2
Joined: Tue Dec 07, 2010 8:54 pm

Re: how to adjust a h-body clutch

Postby cjbiagi » Thu Dec 16, 2010 8:40 pm

The pulley type pedal assembly was used on 71-75 H bodies. Later ones went to a direct pull type pedal without the pulley. Obviously they require different cables. If the pulley you have is pot metal then someone replaced it with a non GM part, the original ones and GM replacements are plastic. You are correct that sometimes you do have to go back and forth to get both the cable and clutch adjusted correctly as they both are dependent upon each other. My main point in my adjustment technique was to make sure people don't just get pedal freeplay and think everything is correct, the freeplay at the pedal must be the result of a proper cable and ball stud adjustment. Generally you are performing both adjustments to get the clutch adjusted. Basically there should be no slack in the cable, the pedal freeplay should result from the gap between the throwout bearing and the clutch fork.
User avatar
cjbiagi
 
Posts: 7973
Joined: Sun Jun 25, 2006 2:37 pm
Location: Glenwood, Illinois

1975 Chevrolet Monza


Return to Best Of

Who is online

Users browsing this forum: No registered users and 1 guest