Lancia Scorpiacarlo & FIAT X1/9 Rear Wheel Bearing Replacement Notes.
During the process of rebuilding the 1988 X1/9 we decided to replace both rear wheel bearings as most all of the rear suspension has already been removed from the car and the original bearings have done over 120,000 miles. The left rear is just beginning to make scrappy noises, right rear appears to be fine. The 1979 and later X1/9 5 speed rear suspension shares many common parts with the Scorpiacarlo. The uprights, wheel bearings, wheel flanges, CV joints, CV joint boots, Axle nuts & washers, lower A arm (bushings & ball joints. The Lancia has anti roll bar mounts which could be installed on the X1/9 A arm and use on the Lancia), Toe adjustment linkage with ball joints and bushings, brake rotor, caliper bracket and a number of nuts and bolts.
The FIAT X1/9 service manual has a good detailed description and photos of how to remove and install the rear suspension upright and wheel bearing replacement. A few special tools will make the chore of replacing rear wheel bearings easier to get done.
1. New wheel bearings, retaining rings, V-ring seals, seal plates (if needed).
2. A reasonable sized hydraulic bearing press.
3. Press bushings to remove the wheel drive flange.
4. Small to medium sized bearing separator.
5. A good sized two or three arm gear puller.
6. Bearing press bushings, including the center race from an old wheel bearing.
7. An old used wheel bearing with one of the two bearing sections removed as a bushing to press in the new bearing with no pressure applied to the center race.
8. Die grinder with cut off wheel.
9. Ball joint puller, like USAG 449 or similar. Do not use a tapered fork splitter as they tend to damage the ball joint boots and could damage the ball joint. Alternatively, a good strong whack on the side of the ball joint tapered shaft housing will usually free the connection. I will not free up ball joint tapered connections this way as it almost always damages something in the process, but it does work.
10. FIAT Tool# A57149 (65mm Octangle) retaining ring removal tool or similar aftermarket tool. Yes, the retaining ring can be removed other ways including hammer and punch, but the correct tool is the best and easiest way. Three sizes of octangle wrenching retaining rings have been used over the years, 65mm or 60mm on the rear and 52mm in the front uprights of Series One Scorpiacarlo and FIAT 128, 65mm and 60mm were used on the rear.
Once the rear upright has been removed from the car and the wheel drive flange has been pressed out of the bearing housing, the center race of the dual angular contact bearing usually stays on the flange. Removing this race can be challenging as there is usually no place for puller jaws to hold and using a chisel between the stuck bearing race and drive flange will damage the drive flange. A better way to remove this stuck race is to use a die grinder with a cut off wheel and gently cut two slots 180 degrees apart just deep enough to fit the jaws of a bearing separator. Be extremely careful to not cut the groove too deep as the cut off wheel can easily cut into the wheel flange. Once the slots have been cut and the bearing separator clamped on, use a gear puller or press the bearing race off the wheel flange. Remove the V-ring seal if it is still there. It is possible they V-ring seal has dissolved, split or ground flat in service. The bearing has seals, but the V-ring seal adds additional water, dirt and environmental protection for the bearing. There is one of these V-ring seals on the CV joint stub axle.
There is a section of the bearing retaining ring that has been peened against a cut out on the threaded side of the upright housing. to prevent the ring from coming loose. Use a brass punch to straighten the peened section of the retaining ring before removal. If the original peened section is not extreme and the retaining rings are still in good condition after removal, they can be re-used. Rotating the rings from left to right could bring a new retaining ring section to peen against the housing to lock it in place. These retaining rings have become precious recently which is why using a brass punch carefully on the peened section of the retaining ring with the hope it can be re-used is a good idea. The retaining rings tend to bow inward during service and should be straightened flat before re-using them if re-use is possible. New rings would be ideal and is the proper way to get this done. Use the FIAT retaining ring removal tool on with an ½” drive impact wrench (OEM FIAT tool is ¾” drive) or a long handled breaker bar or ratchet to un-do the bearing retaining ring. Use a bearing press or good sized gear puller, press out the wheel bearing from the housing. Use care to prevent damaging the sheet metal seal plate when pressing out the bearing. These are replaceable, and should be checked for dents and other damage. If these require replacement, they can be pressed out and replaced with new ones pressed in place. Observer seal plate direction and depth when replacing these plates.
Now it’s time to clean everything up for reinstallation. We used simple green and water to get the goop and grease off the upright and wheel drive flanges, media blasted the housing, treated them with rust preventive and painted them. The flanges were spun cleaned and polished with Scotch brite on a lathe then painted on the back side. A M12x1.25 (wheel bolts) and M8x1.25 (Wheel guide pins) tap was used to clean up the threaded holes on the drive flange. This is a heat treated steel part and it would be a good idea to check for cracks (magnaflux) or other possible problems before re-assembly. We media blasted the upright housings, treated them with rust preventive under coat and painted them with silver color enamel. The rear upright components are well designed and made and usually have few problems even with much greater than stock power levels.
The V-ring seals have proven to be a problem to obtain. This was true even when FIAT was still selling cars and parts in the USA. I had to special order the V-ring seals as part of the set of wheel bearing replacement parts. Harwal: http://www.harwal.com/
and J.W. Winco: http://www.jwwinco.com/products/section17/index.html
have 50mm V-ring seals listed as an industry standard part at available in Nitrile or Viton (more durable, longer seal life). I have not ordered any to confirm, but they should work according to the dimensions listed. Lubricate the V-ring seals with grease before installing the wheel drive flange.
Wipe off any excessive grease or oil on the outside of the new bearing and press the new wheel bearing into the housing by the outside rim of the bearing, if the pressure is applied to the inner race, the chrome steel balls inside the bearing will impale themselves (Brinell failure) into the bearing races causing in dents the bearing race and bearing to failure.
The wheel bearing has two angular contact races, one of the bearing sections can be easily removed by prying apart the center split located on between the two center bearing races if the bearing removal process has not already split the bearing in two sections. The old bearing makes a nice bushing to press in the new bearings by applying pressure only to the outer race of the bearing. Place the old bearing with the removed section on the new bearing and press the new bearing into the housing. This is a good tool to have when replacing wheel bearings. The inner race of the old bearing can be use to do the same when pressing the wheel drive flange into the wheel bearing.
Rotate the wheel drive flange to insure the newly installed bearing is smooth with no bumps or binding anywhere along its rotation.
The rear upright assembly is now ready for installation. The procedure for replacing the front wheel bearings is very similar to replacing the rear wheel bearings.
November 11, 2006