Excerpt from July-August, 1966 Ford Shop Tips

Written by Don Stewart | 31 May 2004

I was rummaging through some papers a few weeks ago and found several old Ford publications called Shop Tips. The tips were for distribution to the public, usually by local Ford dealers. They typically contained 4 to 10 pages and had all sorts of information that could be useful if you did some of your own vehicle maintenance. The July-August, 1966 issue quoted here was devoted to clutch service. The dealer address on the front cover says I got the issue from Bill Marsh Ford, Inc. located in Newtown, Bucks County, PA. Bill Marsh Ford was my preferred Ford store in the ‘60s; I bought several cars from them (all Fairlanes).

CLUTCH SERVICE

All Ford cars use a centrifugal, single dry disc type clutch. The principal components are the clutch disc, pressure plate and release bearing. The clutch is operated by linkage which must be properly adjusted and free of any conditions which might cause binding or excessive force to apply. The transmission, pressure plate, housing, clutch disc, flywheel and crankshaft must be properly aligned to prevent slippage, vibrations and noise. Ordinarily, the clutch does not require periodic service unless one of the trouble symptoms in the Diagnosis Guide is encountered.

CLEANING AND INSPECTION

RELEASE BEARING

Wipe all oil and dirt off the release bearing. THE BEARING IS PRE-LUBRICATED AND SHOULD NOT BE CLEANED WITH SOLVENT.

Inspect the bearing retainer for loose spring clips and rivets.

Inspect the release bearing assembly for burrs which may cause the assembly to drag on the transmission bearing retainer. Any such burrs should be cleaned up with fine crocus cloth. If burrs are found, inspect the transmission input shaft bearing retainer for evidence of scoring. Scoring should be polished out with crocus cloth. Coat the bearing retainer with a thin film of lithium-base grease (Ford Part Number C1AZ-19590-B). Prior to release bearing installation, apply a light film of Lubriplate on both sides of the release lever fork where it contacts the release bearing hub and retaining springs, and to the release bearing surface that contacts the pressure plate fingers. Care must be taken to avoid contaminating the clutch disc with any lubricants as this will cause slippage, and chattering.

Check the release bearing for roughness or noise by holding the bearing inner race and rotating the outer race while applying pressure. If rough or noisy, replace the bearing.

Most release bearing failures are caused by improper clutch pedal adjustments. If the clutch linkage does not have enough free travel, the release bearing will constantly touch the release fingers and will spin whenever the engine is running.

Release bearing failures may also be caused by a bent release lever. Check for excessive wear on one side of the release bearing assembly where the release lever contacts it.

Misalignment between the engine and transmission can also cause release bearing failure.

PRESSURE PLATE AND COVER

Inspect the surface of the pressure plate for burn marks, scoring or ridges. Generally, pressure plate resurfacing is not recommended. However, minor burn marks, scores or ridges may be removed if the flatness of the pressure plate is maintained. If the pressure plate is badly heat-checked or deeply scored, replace the pressure plate and cover assembly. Clean the pressure plate surfaces with a suitable solvent such as carbon tetrachloride, to be sure they are free of oil film. DO NOT USE CLEANERS WITH PETROLEUM BASE AND DO NOT IMMERSE THE PRESSURE PLATE IN THE SOLVENT.

Lay the plate on the floor, being careful not to score or scratch the surface, and force each individual finger down, then release quickly. If the finger does not return quickly, a binding condition is indicated and the pressure plate should be replaced.

Lubricate the pressure plate with lithium-base grease between the driving lugs and the edges of the pressure plate openings as shown in Figure 2. Depress the pressure plate fingers fully, apply the lubricant, and then move the fingers up and down until the lubricant is worked in. DO NOT APPLY EXCESSIVE AMOUNTS OF LUBRICANT.

Editor's Note:Did you notice that Carbon Tetrachloride was recommended as a cleaning agent? Of course, we know today that exposure to Carbon Tetrachloride can cause cancer, visual problems, liver damage, kidney damage, and reproductive disorders. As a result, its use is not recommended.

CLUTCH DISC

Inspect the clutch disc facings for oil or grease. ELIMINATE THE SOURCE OF ANY OIL OR GREASE BEFORE REPLACING THE DISC. An excessive amount of grease in the pilot bushing or release bearing hub will find its way to the disc facings. Too much lubricant in the transmission or a plugged transmission vent will force lubricant out the input shaft and onto the disc facings. Likewise, lubricant leaks from the rear of the engine will also find their way to the clutch disc facings.

Inspect the clutch disc for worn or loose facings. Check the disc for distortion and for loose rivets at the hub. Check for broken springs. Springs loose enough to rattle will not cause noise when the car is operating. Replace the disc assembly if any of these defects are present. BE ESPECIALLY CAREFUL WHEN INSTALLING THE DISC NOT TO CONTAMINATE IT WITH OIL OR GREASE.

PILOT BUSHING

Check the fit of the clutch pilot bushing in the bore of the crankshaft. The bushing is pressed into the crankshaft and should not be loose. Inspect the inner surface of the bushing for wear or a bell-mouthed condition. If the bushing is worn or damaged, replace the bushing.

FLYWHEEL HOUSING ALIGNMENT

Alignment of the flywheel housing bore and rear face with the engine should be checked as a possible cause of any of the following: excessive transmission gear wear; transmission jumping out of gear, especially third gear; drive line vibration; excessive pilot bushing wear; noisy release bearing; or excessive clutch spin time.

Maximum "face" runout is 0.009" and maximum "bore" runout is 0.015". Not more than 0.010 inch thickness shims may be used between the flywheel housing and the engine to bring the face and bore alignment within specifications. If a 0.010 inch shim will not bring the face and bore alignment within specifications, replace the flywheel housing.

ADJUSTMENTS

CLUTCH PEDAL

Adjust the clutch pedal free travel whenever the clutch does not disengage properly, or when new clutch parts are installed. Clutch free play (free travel) is the distance the clutch pedal pad travels from the top (released) position until the release bearing contacts the pressure plate fingers. At this point, a definite resistance can be felt.

1. Disconnect the clutch return spring from the release lever.

2. Loosen the release lever rod locknut (Figures 6).

3. Turn the adapter portion of the adjusting assembly until a firm resistance is felt. The release bearing is now contacting the clutch pressure plate fingers (levers).

4. Back the locknut off (forward) and insert a feeler gauge (0.128 inch thick for 8 cyl.; 0.178 inch thick for 6 cyl.) against the back face of the rod adapter. Then, tighten the locknut finger-tight against the gauge.

5. Remove the feeler gauge. Hold the locknut in position and tighten the adapter against the nut. Torque the adapter 10-15 ft.-lbs.

6. Install the clutch return spring.

7. Check the free travel at the pedal. It should be from 7/8 to
1-1/8 inches. Readjust if necessary.

As a final check, measure the pedal free travel with the transmission in neutral and the engine running at about 3000 rpm. If the free travel is not a minimum of 1/2 inch, readjust. Otherwise, the release fingers may contact the release bearing continuously, resulting in premature bearing and clutch failure.