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FAQ

Project.
Clutch FAQ
Various Contributors

Q: Are spider clutch cables different lengths for certain models? I have to tighten mine all the way to the end of the threads for the clutch to work properly. It acts as if it were too long. I have a new clutch, pressure plate, throw-out bearing and clutch fork.

A: The aftermarket ones do seem to be a bit longer but not enough to worry about. This can also be caused by the cable siezing, which will cause it to break. This can also lead to pedal bending or breaking, cracks in the firewall, and the clutch release lever breaking. Check and/or run a new ground strap for the engine. The old ground strap does not function as well as it should. When this happens the engine will ground through the clutch and accel. cable, drying out and corroding both cables.

For cracks in the firewall, the right fix welds in some reinforcing metal. I’ve heard some people disassemble and use a megawasher to spread the load. My car had the click for 80K miles before it was diagnosed so if it is the firewall you can keep an eye on it until you can really fix it.

A: the pedal will rise as the clutch wears, it could be a remanufactured clutch that is too thick,more likely the wrong throw out bearing as the early bearing was thinner

Q: I’m replacing 850 clutch soon, but I’d like to read a few horror/success stories before the floor jack rolls. How much did you pay for a new plate?

A: The pressure plate, disk, and throw-out bearing are less than $100.

Q: Will a broom make a decent 850 alignment tool?

A: I don’t think so - the input shaft is only about ½ inch in diameter.

Q: How many people do I need to help change the clutch?

A: You can do it alone, but it’s would be nice to have at least one extra pair of hands.

Q: What sort of clutch wear should I expect/look for?

A: If the clutch is slipping, I wouldn’t even look at it just take it off and throw it away. Look for unevenness on the flywheel, and consider having it surfaced [low cost, big benefits. You don’t want to be back in here anytime soon, right?

Q: How do I get the top bolt out of the starter? From underneath with a three foot extension and a universal on my ratchet. The long extension allows for a gradual angle to link up with the bolt head. Someone on top helping to line things up makes it a lot easier. It’s a little tricky but it does work.

Q: How do I get the top bolt out of the bellhousing ? From the engine compartment, with a special tool. Actually, it’s a 19mm wrench with a spceial bend in it.

Q: How do I adjust the clutch on my 124?

A: With the clutch fork return spring removed, push the fork forward until it hits the TOB. Snug up all the slack in the cable then take an extra ¼". Re-attach the spring. Have someone operate the clutch while you observe the action of the clutch fork from underneath. Make sure it’s not hitting the bell housing before the pedal is to the floor. (That’s how cables are broken and pedals are bent)

(Eli, this procedure works OK on my ‘78 Spider, but hasn’t been tested elsewhere - bs)

Q: I’ve heard my flywheel described as a ‘two step’ flywheel, what’s that mean?

A: If you look at a stock wheel, you will see the outer step, where the pressure plate is bolted, is above the inner step, where the disk contacts the flywheel. If you cut the flywheel to a single step, the released pressure on the disc is higher and the effective release dimension is reduced. With a new fat disc and a new pressure plate surface the clutch may not release. Contrary to some opinion, you should always face the flywheel. It will smooth clutch action, increase clutch life and recduce clutch temperature.

Q: I recently purchased the complete set of clutch plate, throw out bearing and cover. The units look right, but the cover/pressure plate has a circle of curved metal pieces (like inward facing flower petals for lack of a better description) that seem to line up with the throwout bearing when I’ve eyed it. There isn’t any center race or whatever that is on the stock unit. The word "Valeo" appears on both the plate and the cover. The bearing is Borg-Warner, I believe.. This stuff all seems to fit together, but is this an original mod or a new idea?

A: I just had the ‘flower petal’ type installed on my Sedan to replace a pressure plate of the old design. It works perfectly quiet, good engagement. Methinks it’s just a newer design that has fewer parts and is easier to make with automation.

Q: I just bought an 82 Spider 2000FI. Got it running yesterday well enough to go to the gas station and put good gas in it. I noticed that when I stepped on the clutch it would click. Shifting seemed smooth enough, (sloppy shifter). Any ideas.

A: Might want to check the point where the cable clips in to the pedal. I’ve had curious clutch pedal sounds coming from the stress/strain of bending metal right before the pedal breaks & I’m walking. Due to poor design, misadjusting or whatever, these pedals tend to bend then break right below the cable attachment. then again, there is a spring which could just need oiling & bushings on the pivot shaft.

A: The point where the cable passes the firewall can stress and crack the firewall. The right fix welds in reinforcing metal. I’ve heard some people disassemble and use a megawasher to spread the load. My car had the click for 80K miles before it was diagnosed so if it is the firewall you can keep an eye on it until you can really fix it.

A: I was up under the car last night and it appears that the fork sticking out of the trans was getting hung up on the Speedometer cable. Zip tied the speedometer cable to the ground.

Q: My clutch is frozen! I hot-water washed the engine compartment in january prepping for my engine compartment repaint/general wiring cleanup/etc. Any ideas on freeing this up?

A: If you press the clutch pedal and someone can confirm that the clutch lever is moving, then the quick fix method I have used to cure this is to start the car in 1st gear by pushing, keep the clutch pedal depressed while driving around accellerating and decellerating the engine. If the clutch disk is rusted to the flywheel, which it sounds like, it should pop loose with no damage to the components nvolved.

A: Sounds like you might have sprayed some water between the flywheel and clutch disc.

Everytime I clean the engine compartment in any of my cars, I immedietly drive it up the road and back for about 10 miles to make sure everything is dried off.

Q: When I got into my car yesterday morning the clutch pedal went straight to the floor. I bought a spare clutch cable, but to my surprise the clutch pedal itself was broken at the top and was very much out of shape. I have got the pedal repaired and strengthened (with a bit of modification) so my question is are there any alternative for replacement in the fiat range to the 124 pedal, i.e. will any of the 126/7/8 x-19 model’s fit as a replacement?

A: Might be worth looking for a 124 Sedan part, or just investing a lot of time in fixing the existing part., there are other items you need to look at-Typically when the clutch pedal or cable break, it’s because the clutch has gotten horribly stiff. We usually reinforce cluch pedals with a small triagnular bit of metal up at the top, but with a stiff clutch and this mod, the next thing that might happen is that your firewall will go away where the clutch cable goes through!

Q: My Spider seems very ‘jerkey’ whem I’m starting off. What can cause this?

A: Replacing the tranny mount and the worn engine mounts with new mounts can reduce and virtually eliminate the problem.

A: Spiders with the bell crank type carb linkage will have jerkiness. As the engine rocks or moves it pulls and pushes on the carb linkage thereby working the throttle. The linkage is a solid connection between the engine and body and cannot absorb relative motion between the two. The cable linkage got rid of this problem. More rigid motor mounts would reduce this effect.

A: Check the doughnut at the back of the transmission. If it’s broken

it can cause this ‘jerkeyness’

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Helpful hint: I recently had a new clutch installed in my 124 and a new cable installed about 4 months ago. Last week the clutch started to get grabby and pulling away in first gear was hard to do smoothly. Since everything was relatively new I was concerned. I pulled off the clutch cable and shot it full of spray lithium grease, making sure it ran all the way to the other end. Put the cable back on and voila smooth, easy clutch action. Just goes to show that even a new cable can benefit from this.

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For the parts substitution section:

While scrounging for parts one day I noticed a set of VW rubber clutch and brake pedal pads on a 78 Spider! Looks like they fit like a glove.

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For the performance modifications section:

Flywheel and Clutch Assemblies - For competition use, the flywheel and the clutch must be modified so that downshifting at high speed will not damage the clutch pressure plate. If this is not done, the reversed loads when the engine is used for braking (either intentionally or inadvertently) will buckle the drive straps on the pressure plate and cause a severe unbalance. This is immediately followed by the flywheel shearing off the flywheel attaching bolts.

The flywheel is modified by installing three large dowel pins. The pressure plate has three bosses which are drilled and reamed to fit over the three dowel pins. These pins provide drive torque in both directions and prevent the clutch drive straps from buckling under reverse loads.

The flywheel can be lightened by machining material away on the back side. Sufficient material must be left to provide adequate support for the large dowel pins.

The flywheel and pressure plate must be balanced after modifications are complete.

A sintered metallic clutch disc is recommended for racing. This and the modified flywheel and pressure plate are all available as an assembly from PBS.

The sintered metallic clutch disc is not recommended for street use because it must be broken in properly to give satisfactory results. Break-in procedure involves slipping the clutch until it heats the flywheel and pressure plate surfaces enough to glaze them. This results in a hard, wear resistant surface on the cast iron parts. If a material other than cast iron is used for the flywheel, it must have a hardened clutch surface to be compatible with the metallic disc.

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I’ve left this whole thread out as it’s all inconclusive. Several wrong theories, and conflicting advice makes it too confusing. Maybe we can make sense if it at some point, but right now we don’t have enough solid data to reach any conclusions. I’m leaving the text in this file for now just to keep track of it, not to be part of the FAQ. - bs

Dan, James, Bill, and anyone out there replacing your clutch. I had similar problems during the restoration of my ‘75 spyder. I had my flywheel resurfaced at a local "machine shop", and installed it along with a new pressure plate, disk & TOB all exact dupes of the parts I had on the car & working correctly. However, the fun started when I was unable to adjust the clutch freeplay w/o the fork hitting the forward edge of the opening in the bell housing. The problem is with the machinist who decided to remove approx ¼ in. of my flywheel, leaving me 13mm of thickness on the outer ring, 18mm on the inner. The used replacement measures 19 & 24 mm respectively. This translates out to approx ¼ inch. That is why the TOB is unable to get the clutch disengaged. It’s just too far away. Bill compensated for the thinner flywheel by raising the height of the pivot, but the problem remains, and may get worse because the thinner flywheel may encounter warpage, heat checking etc due to its thinner mass.

My point is simply this. If you are going to have your flywheel resurfaced make sure you find out just how much is going to be removed and compare your numbers with those above. Keep in mind new flywheels are rare & expensive. Good luck Mike ‘75 124 spyder.

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I’ve never turned a flywheel when replacing a clutch. At the Saab-Alfa-Hyundai dealer I worked at they never did either. I’d like your guy to explain to me what physical effect from not turning the flywheel would cause a clutch to not completely disengage. He is full of it. The reason you are supposed to turn the flywheel is to give the new disc a clean, flat surface to contact (like the face of the shiny new pressure plate). However, I’ve never experienced a problem with not doing it. In fact, Acura specifies that the Integra flywheel be replaced with the clutch as the surface cannot be turned, as it will reduce the flywheel height and the clutch will then slip!

The clutch "warranty" is also a bunch of b/s, as unless it explodes shortly after install they will blame any failure on improper installation or abuse. Technically, it is BEST to resurface a flywheel, but few if any actually do it.

I have no idea what a two-step flywheel is supposed to be.

Dwight V.

1970 124 Spider

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The two step. If you look at a stock wheel, you will see the outer step, where the pressure plate is bolted, is above the inner step, where the disk contacts the flywheel. If you cut the flywheel to a single step, the released pressure on the disc is higher and the effective release dimension is reduced. With a new fat disc and a new pressure plate surface the clutch may not release. Contrary to some opinion, you should always face the flywheel. It will smooth clutch action, increase clutch life and recduce clutch temperature.

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Right. Guy Croft says that the step should be 20 +/- 2 mils.