Flywheel/clutch Need Replacing?

Tim83

Member
Sep 18, 2016
47
14
18
Good afternoon folks,

I'm replacing a leaking rear main seal and I was hoping you can weigh in on whether or not my clutch, flywheel, pivot stud, throw out bearing, or spacer plate need replacing. I've including some pictures and my own thoughts but please let me know what you think. Thank you for your time.

- Flywheel: The clutch side feels smooth and has a blueish hue. It's not the factor flywheel as there is a Centerforce sticker on it so if anything I think it might need to be resurfaced?

In the photo of the engine side of the flywheel there are raised sections that feel sharp and jagged. I feel like they shouldn't be there.

- Spacer plate: It feels a little warped but otherwise fine. Do you see the scoring in it? I think this was caused by the jagged section of the flywheel.

- Clutch: How does this look? I never had any problems with slipping or pedal feel.

- Pivot stud: The inside of the bellhousing was very dirty but I can't tell if the pivot stud needs replacing.
 

Attachments

  • IMG_5645.JPG
    IMG_5645.JPG
    635.9 KB · Views: 558
  • IMG_5646.JPG
    IMG_5646.JPG
    627.8 KB · Views: 473
  • IMG_5647.JPG
    IMG_5647.JPG
    716.4 KB · Views: 403
  • IMG_5648.JPG
    IMG_5648.JPG
    512.6 KB · Views: 393
  • IMG_5649.JPG
    IMG_5649.JPG
    588.9 KB · Views: 440
  • IMG_5650.JPG
    IMG_5650.JPG
    647.4 KB · Views: 482
  • IMG_5651.JPG
    IMG_5651.JPG
    473.7 KB · Views: 431
  • Sponsors (?)


Oh Jesus. It looks exactly like someone put a Centerforce clutch in a Mustang. Like a disk with a ton of surface friction but a stock pressure plate; so it just burns like hell when you engage it. And yes, Centerforce and I have some bad blood, so I am very biased.

You can resurface that flywheel no problem, it's not expensive. The friction material is unevenly worn (because it is not properly engineered), and in some places far too close to the rivets. I would go ahead and replace that clutch before it causes more problems. There are a ton of options out there, but I'm just saying, nobody ever had anything negative to say about a King Cobra clutch. SPEC and Mcleod make some great stuff too.

With any clutch, the inside of the bellhousing is going to be filthy. The pivot stud rarely needs replacing. If it has sharp edges on it, go ahead and replace it. They are not expensive. Put a solid wad of grease on the new one. The clutch release bearing should be replaced every time, and sometimes in between. Make sure it's a quality bearing. Something that is made by BCA/National, SKF Sweden, or NTN if at all possible. Also replace the pilot bearing out of principle. Autozone and Advance have a free rental tool to remove the old one with ease. You just hammer the new one in with a big socket. Most of the clutch kits come with a pilot bearing, clutch release bearing, and an alignment tool. The bearings can be of dubious quality, even if it's a quality clutch.

Kurt
 
That spacer plate was rubbing on the flywheel. That thing had to be making noise at some point.

The clutch friction plate looks worn...the grooves are disappearing towards the center. The pivot stud does look like it has some wear.

The flywheel looks to be billet steel and could be turned. The spacer plate could be straightened out and put back on ( it just takes up space between the engine and trans.

The clutch pressure plate, friction plate, pilot bearing, throw out bearing, and pivot stud should be replaced. Also, check the bearing retainer sleeve on the transmission. If it is scored you may want to replace it too. The after market ones are steel...way better than the stock aluminum ones.

Stay away from cheap throw out bearings.
 
Kurt/90sickfox,

Thank you both for taking the time to respond to me. I'm going to replace all the parts per your recommendations. I looked at some clutch choices briefly and figured I would provide some detail on my particular car. With the current set up it made 280HP and 313TQ at the wheels when I had it on the dyno this spring. As the car stands now I do not plan to add any additional power but I do plan to put a naturally aspirated 331 or 347 in it within the next near or two. With that in mind, would it be better to get a stage 2 clutch?
 
Yes...stage 2 would be better... The stroker motors could push you above the 350tq mark.

They tend to be a little grabby. A dual friction clutch would probably be best. I've never had one but my next clutch will be dual friction. Unless, I do a hydraulic clutch conversion. :nice:
 
@Tim83
Everything said rings pretty true, good, honest replies, some of the content goes a bit over my head, but I can still contribute something. There is plenty of space between the front of the flywheel and the spacer plate normally. The only way it could contact the flywheel would be due to a "hit" where it's exposed below the crank centerline, a rock, maybe, small animal, something which pushed it in far enough to contact momentarily, then it sprung back out. Other than covering the lower part of the housing, sole purpose for that plate is to locate the starter accurately via the big round hole. Left out, as my nephew wanted to do, the starter will be mislocated and possible damage to gear teeth will result.

Rivets are mighty close to danger on the disc, I'd pitch it for sure. Clean the flywheel carefully with solvent, and look real closely for hairline cracks. See any, S.C. the flywheel. The engine is 5.0 HO? Externally-balanced, get the CORRECT flywheel counterweighting and # of ring-gear teeth, 50 in-oz balance, 164 teeth, someone correct me if I'm wrong on that!

Eng. side of flywheel (roughness) adds wind-resistance, prevents quick wrap-up? :O_o: Nah, but the surface which contacts the crankshaft flange should not have any serious dings in it.

Someone mentioned the Input Shaft Bearing Retainer: if it's still the factory aluminum one, pitch it for sure, even if it's not scored! The stock plastic cable quadrant under the dash can be a real PITA. I replaced my Cobra's with an aluminum one, and heavy-duty cable. This is all just my two cents worth. imp
 
I'm looking at picking up a Mcleod clutch kit which will come with the pilot and throwout bearings. Does anyone know how decent the throwout bearing is? I don't mind buying a better one but I won't if I don't have to.
 
  • Like
Reactions: 1 user
I'm looking at picking up a Mcleod clutch kit which will come with the pilot and throwout bearings. Does anyone know how decent the throwout bearing is? I don't mind buying a better one but I won't if I don't have to.
@Tim83
Sorry, can't tell you about the throwout they supply, but can say this: No matter whose bearing it is, it's gotta be better than the thing I found in my '96 F-150, ALL PLASTIC almost. imp
 
McLeod usually has some decent quality stuff. I've installed their clutches and bearings in a few cars and haven't had problems.
 
  • Like
Reactions: 1 user
Thank you again to everyone who offered assistance to me. My plan was to have the car back together by tomorrow but the McLeod clutch I ordered won't arrive before I leave for vacation this weekend so the project is going to have to wait. I already had my flywheel resurfaced so once the clutch comes everything will be reinstalled. I'll post another update when I get back. Thanks again!
 
A stroker engine needs a SPEC 3+ or comparable. If you are more into the experience (like myself), get a SPEC 4+ so it feels like your brain is going to pop out of your head when you drop the clutch on the line.

Kurt
 
What would you guys recommend for a NA 306 making 280 to the wheels through a T5? Street car with drag radials
I recommend beating the snot out of it, but be careful with that t5, and save up for an better transmission, the t5 will be ok if you treat it right, as for clutches, I've used the cobra clutch stuff for 50k with no problems, I beat the snot outta my ride regularly with a t5 but I use inexpensive nothing special rear tires that have marginal grip quality.
 
  • Like
Reactions: 1 user
I recommend beating the snot out of it, but be careful with that t5, and save up for an better transmission, the t5 will be ok if you treat it right, as for clutches, I've used the cobra clutch stuff for 50k with no problems, I beat the snot outta my ride regularly with a t5 but I use inexpensive nothing special rear tires that have marginal grip quality.

No power shifting or time at the strip.
 
  • Like
Reactions: 1 user
Just to put a cap on this thread. I replaced everything you folks recommended and it's all set. The Mcleod clutch grabs right off the floor. I realize now I had a little clutch chatter with the old set up.

Thanks again to everyone who took the time to read and respond!
 
  • Like
Reactions: 1 user
Just to put a cap on this thread. I replaced everything you folks recommended and it's all set. The Mcleod clutch grabs right off the floor. I realize now I had a little clutch chatter with the old set up.

Thanks again to everyone who took the time to read and respond!
Clutch Adjustment for stock and aftermarket setups
Revised 28-Apr-2016 to include need for longer cable with single hook quadrant

Clutch adjustment with stock cable and quadrant
There is a self-adjusting mechanism for the clutch cable. As the clutch wears the cable tension changes, that is why there is a self-adjusting mechanism built into the clutch pedal. There is a toothed plastic quadrant with a ratchet pawl that engages the quadrant. As you pull up on the clutch pedal, it ratchets and takes any slack out of the clutch cable. Mess around with the pedal or even bump it while the end that fits in the clutch fork is loose, and it tries to take up the slack in the cable. That has the effect of shortening the cable.

Do the clutch adjustment first before considering any other problems. With the stock plastic quadrant and cable, pull up on the clutch pedal until it comes upward toward you. It will make a ratcheting sound as the self adjuster works. To release to tension of the stock quadrant, use a screwdriver to lift the ratchet paw up and out of engagement with the quadrant teeth.

You can use a screwdriver to lift the ratchet pawl off the quadrant teeth. That will allow you to move the quadrant to allow more slack in the cable. If the cable is too loose, pull up on the pedal. The ratchet pawl will allow the quadrant to take up the slack in the cable and lock the adjustment.

Adjustable cables are used when the plastic quadrant is replaced with an aftermarket metal quadrant. The downside to this setup is that you have to get under the car to adjust the clutch. Add a firewall adjuster to an adjustable cable setup and you can spare yourself from getting back under the car to make any fine adjustment that you desire.

The fancy 2 and 3 hook quadrants are for use with stock length cable and a firewall adjuster. Use the firewall adjuster and screw in and out to take the slack out of the cable and get the clutch engagement point just where you want it.

Binding clutch cable
A binding clutch cable will make the clutch very stiff. If the cable is misrouted or has gotten too close to the exhaust, it will definitely bind. The binding common to adjustable cables is often due to misplacement of the adjusting nuts on the fork end of the cable. This will also cause the cable to wear and fray. Both nuts should be on the back side of the fork so that the domed nut faces the fork and the other nut serves as jam or locknut to the domed nut.

Clutch pedal adjustment
Clutch pedal adjustment with aftermarket quadrant and cable: I like to have the clutch completely disengaged and still have about 1.5” travel left before the pedal hits the floor. This means that I have only about 1” of free play at the top before the pedal starts to disengage the clutch. Keep in mind that these figures are all approximate. When properly adjusted, there will not be any slack in the clutch cable. You will have 4-15 lbs preload on the clutch cable. With a non adjustable cable and a firewall adjuster, the cable needs to go in the second hook of the quadrant. Single hook quadrants used with a firewall adjuster may make the clutch too tight, causing it to slip. The possible exception to this is the Maximum Motorsports cable which is a bit longer to make it work with a single hook quadrant.

Adjustable clutch cable tips:
Loosening the cable adjustment nut (throwout bearing arm moves to the rear of the car) moves the disengagement point towards the floor.

Tightening the cable adjustment nut (throwout bearing arm moves to the front of the car) moves the disengagement point towards the top of the pedal.

Firewall adjuster tips
Turning the firewall adjuster IN makes the engagement point closer to the floor since it loosens the cable. You have to push the pedal to the floor to disengage the clutch. Too loose a cable and the clutch won't completely disengage and shifting will be difficult. Gears will grind and you may have difficulty getting the transmission in first gear when stopped.

Turning the firewall adjuster OUT makes the engagement point farther from the floor since it tightens the cable. You push a short distance to disengage the clutch. Too tight a cable will cause clutch slippage.

Aftermarket solutions to the problem:
The quadrant needs to be replaced if you use any type of aftermarket cable or adjuster. My preference is a Ford Racing quadrant, adjustable cable and Steeda firewall adjuster. The adjustable Ford Racing cable is just as good as the stock OEM cable. It allows a greater range of adjustment than a stock cable with a aftermarket quadrant and firewall adjuster. Combined with the Steeda adjuster, it lets you set the initial cable preload and then fine tune the clutch engagement point to your liking without getting under the car.

Using a stock OEM cable, firewall adjuster and a single hook quadrant may result in not having any free pedal travel before the clutch starts to disengage. I found this out the hard way.

See Summit Racing - High Performance Car and Truck Parts l 800-230-3030 for the following parts.

Ford Racing M-7553-B302 - Ford Racing V-8 Mustang Adjustable Clutch Linkage Kits - Overview - SummitRacing.com Cable and quadrant assembly $90

The Ford Racing Adjustable cable is available as a separate part:
Clutch Cable, Adjustable, Ford, Mercury, 5.0L, Kit FMS-M-7553-C302_HE_xl.jpg

[url=http://www.summitracing.com/parts/SDA-555-7021/]Steeda Autosports 555-7021 - Steeda Autosports Firewall Cable Adjusters - Overview - SummitRacing.com
Steeda firewall adjuster. $40

575166.jpg


Fix for the quadrant end of the cable popping out of the quadrant when installing a replacement cable courtesy of Grabbin' Asphalt
imag0825-jpg.85883.jpg
[/url]

Help for those who have replaced the clutch assembly and are still having problems with adjustment:
The next step doesn't make much sense it you already have the transmission installed, but just for sake of discussion, here it is:
The throwout bearing sits in the clutch fork arm with the wave springs pressing on the rear flange of the throwout bearing.

?temp_hash=3b781a008f68f70d0bde9d6310e08fdb.gif

Major differences between the distance between the flywheel surface and the clutch fingers may require tinkering with the clutch fork pivot ball. Stack your old pressure plate, clutch disc and flywheel up like they were when installed in the car. Tighten down all the pressure plate bolts and measure the distance between the clutch fingertips and the flywheel face.
Too much thickness will cause the clutch fork arm to sit too far back to get the clutch cable on the quadrant. It may even sit against the rear or the bell housing hole for the clutch fork arm. In that case, reduce the pivot ball height.
Too little thickness will cause the clutch fork arm to sit too far forward and bottom out against the front side of the bell housing hole for the clutch fork arm.. This will prevent the clutch from fully disengaging.
In other words, the clutch fork arm should sit positioned midway or a little towards the rear in the bell housing hole for the clutch fork arm when the cable is properly tensioned.