FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: FE4SPDMustang on May 02, 2021, 11:03:31 AM
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I am not sure if I should break my issues into two post or leave it combined. I created an account because I read another post dealing with a similar issue I suffer.
I used the suggested spacers shims and I have as much as .070 which allows the rockers to float on the shafts. ( I have the POP stands/spacers rockers on Edelbrock heads) I have some tappet noise. The preload is correct. I thought the rocker may be floating on the shafts and slapping against the stands. Does that seem logical with .070+ in a couple places?
My second issue is the difficulty of getting the trans into first while running and reverse sometimes. I think the pivot on the clutch release has some movement. Would this keep the clutch from full disengagement?
The transmission was rebuilt and has about 3200 miles on it.
Any pointers would be appreciated.
The car is a 67 big block mustang.
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Welcome,your in the right place for FE info.
On the rocker side clearance Doug (POP) told me .015” total between rocker arms total. Tighter ok on the single end rockers. My end ones are about .020” because a .015” shim makes it too tight cold IMHO.
The aluminum rockers have their own sound though especially if you have cast valve covers. Are you sure the rockers are not hitting the baffles,that makes a very lifter like noise.
As for the clutch issue,need more info.
What clutch?
What linkage?
What headers? (Yes this makes a difference,I’ll get into if you have the ones I had a problem with)
Transmission?
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Well, lets put all the information out there. The headers are Hooker Super Comps. Factory clutch linkage, NOS. I took the clutch pedal support to Mustang Steve and had him install his full roller bearing pedal pivot kit. it's smooth as a baby's ass compared to Ford's plastic bushed pedal. Centerforce clutch. ( Never has it stayed down at RPM) Stock bellhousing and four speed Top loader.
I have factory aluminum penthouse valve covers. There is no contact with the valve cover. ( Had that issue with factory adjustables)
I noted slight movement were the lever pivot is riveted to the bellhousing.
I hope that allows some insight for possible causes and remedies.
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Two things...
1. Check the distance between the throw out bearing and the pressure plate at rest. You should have 1/16-1/8" of free play there.
2. I've been selling clutches since 2008 and this is the biggest gripe I hear from people calling to replace Centerforce clutches. Their little counterweight design adds clamping force at the most inopportune times, causing drag like this.
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Is it a short pilot FE top loader?
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Thank you. I started running the Centerforce on my 1969 Datsun 1600 SSS car in the early 80's being the factory clutch wouldn't hold the engine. The 50MM side draft Mikuni/Solex. Even Datsun in 1969 used a hydraulic clutch. Never an issue other than exploding the 4 speed transmission counter shafts.
BLykins, what was your thought on rocker shims? I did measure. .060 on one end was the largest spacing. Most sets averaged .018-.025. Should I disregard or address this before I button it back up?
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It is the original trans to the car. The trans was rebuilt and second gear was changed.
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I would look at the shifter and all bushings,make sure the lever arms are properly centered in neutral.
If the shifter is sloppy it can cause two transmission arms to try and engage gears.
Once in gear is the clutch pedal a light switch or do you have good take up travel?
The loose pivot may not be helping ,it does sound like the clutch is not releasing ,what about shifting to other gears ,engine running at a stop?
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Thank you. I started running the Centerforce on my 1969 Datsun 1600 SSS car in the early 80's being the factory clutch wouldn't hold the engine. The 50MM side draft Mikuni/Solex. Even Datsun in 1969 used a hydraulic clutch. Never an issue other than exploding the 4 speed transmission counter shafts.
BLykins, what was your thought on rocker shims? I did measure. .060 on one end was the largest spacing. Most sets averaged .018-.025. Should I disregard or address this before I button it back up?
I would tighten it way up. You don’t want any slop there.
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FE4SPDMustang, welcome. I’m new here as well but I’ve got the same car as you (‘67 S Code Coupe) and will be going through some of the same things that you are. Hopefully we can learn from everyone here on the issues. I agree with Cyclone03 regarding the sloppy pivot. That can certainly cause clutch engagement/disengagement issues.
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What cam and lifters are you running?
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FE4SPDMustang, welcome. I’m new here as well but I’ve got the same car as you (‘67 S Code Coupe) and will be going through some of the same things that you are. Hopefully we can learn from everyone here on the issues. I agree with Cyclone03 regarding the sloppy pivot. That can certainly cause clutch engagement/disengagement issues.
It's a 67 Q code. Isky 3/8" pushrods, Johnson lifters on a custom grind. 232/242@ 50 respectively with .567/.579 lift. I need more cam but I can't completely compromise vacuum because of power brakes.
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I would look at the shifter and all bushings,make sure the lever arms are properly centered in neutral.
If the shifter is sloppy it can cause two transmission arms to try and engage gears.
Once in gear is the clutch pedal a light switch or do you have good take up travel?
The loose pivot may not be helping ,it does sound like the clutch is not releasing ,what about shifting to other gears ,engine running at a stop?
I had Bill Heeley restore the factory shifter. It's tight and adjusted correctly. The nuts haven't shifted and it's smooth while it's not running.
No bushing issues with any linkage. I am leaning towards the fact the pivot is loose. I thought with all the years experience here someone had a similar issue.
There is VERY little free free travel before it picks up. I did adjust the lower rod assuming the problem was the clutch had broken in and it just needed to be a bit longer. I also used the old trick of using a 65-6 emergency brake lever spring and running it from the lever to the lower control arm pivot. It keeps the throw out bearing from riding the plate.
I know many have ran into unique issues and I hope the vast experiences would yield an answer to unusual situations.
On the rocker shaft two of the thread inserts in the Edelbrock heads had started to pull, so the nuts on the studs absolutely weren't at 50lbs. I have a feeling the shaft was flexing being it was two studs on one end. I am going to try and make the repair on the engine. I came up with an idea for a drill and tap guide. The machine shop in our repair facility is going to CNC it for me. I ordered a Big Sert set for 3/8-16 to make the repair.
I would assume Edelbrock would have a lot of insert failures being they use a standard helicoil insert.
Thank you all for the information.
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If you are failing helicoils with that mild cam you probably have mechanical interference or the fasteners were not properly tightened.
I agree with others that you need to tightened up the side to side clearance to .015 or so.
Any twist in the clutch linkage is a problem. The mechanical linkage on my personal car was transformed once we straightened it out.
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