POSTED BY 69MyWay
Swapping the rack & pinion in a C4
The rack first appeared in the Y body chassis as standard equipment on the 1984 Corvette. This tested and proven technology offered less weight, less moving parts, and more precision steering than systems of the past. Two version were available with the Z51 quick ration and FE soft ride cars for different driving styles. Over time, the rack has a tendency to develop leaks around the seals, and or develop performance issues resulting in loss of power steering during spirited driving and slows power assistance.
While the rack & pinion is buried deep in the front suspension, it is not that difficult of a task for the average do-it-yourselfer to swap out using only basic hand tools and a little garage space. Our rack had developed a slow leak around the bottom input shaft seal. This means the internal seals were leaking allowing excess fluid to puddle in the void behind the dust cap and steadily drip out whether while in use or just sitting in the garage. In a matter of 1,000 miles the reservoir could drain to the point the pump would growl.
Our swap started with a trip to the local Parts America. We picked up a rebuilt unit for a cool $140 out the door less the $125 core deposit. We also picked up a bottle of Royal Purple synthetic fluid to top off the reservoir once the bottom was sealed tight.
Back in the garage we jacked the car up high enough to remove the tires and have ample room to slide underneath. A large oil drain pan worked perfect for catching the excess fluid once the system was ready to drain. From the topside we used a 7mm socket to remove the fastener around the steering input shaft cover. Once that was removed we used a 11mm socked on a long extension to remove the pinch clamp bolt holding the steering shaft to the rack. The head of the bolt was pointing straight up with the steering wheel locked in the center position.
The feed and return line on the rack use a 18 mm tubing wrench. We found it best to remove the return line first to gain the most access to the pressure line. Once these lines are off the system will start draining into the catch pan. With a flathead screwdriver we released the return hose clamp and slide the return hose off the reservoir. We also slipped under the car with a 10 mm and 7 mm to release the clamp brackets retaining the return hose assembly to the rack and then lifted the entire return line assembly out of the car. If equipped with a steering cooler, we would be pulling the cooler out at this time along with this line.
Using a 15 mm wrench and socket we removed the main rack mounting bolt from the driver side of the rack followed by removing the two retaining clamp bolts on the passenger side with a 13 mm socket. At the tie rod end, we pulled the carter pin and used a 18 mm socket to remove the tie rod nut, then pounded the tie rod free with a pickle fork. We had a fork on hand, but if you don’t have one, they can be rented at your local auto parts store.
In order to get the rack out of the car you have to remove the sway bar. We used a pair of 15 mm wrenches to release the bar from the side mount brackets, then used a 15 mm socket to release the sway bar mounts from the frame rails. There are two bolts on each side that hold the sway bar mounts in place. With a bit of wiggle and twist the sway bar slid out through the driver side. With the sway bar out of the way we simply pried the rack free from the frame and twisted and turned until it slid out the driver side as well.
We took this time to spray some engine degreaser on the cross member and supporting suspension components that suffered the fate of the fluid leak mixed with road grime. This is the best time to get the area clean as there is very little access once the rack is in place.
We had recently had an alignment on this car and didn’t want to run right back down and do it again. The challenge was to get the replacement rack in the exact same adjustment as the original one. We solved this by taking a five foot long 2x4 and placing the old rack on top with the steering input centered. We drilled a 3/8†hold in the wood directly in line with the main rack frame mount support hole. Using a long 3/8†bolt, we secured the rack to the board and aligned the tie rod ends facing threads up on each end. We marked the location of the grease fittings, moved the ends, then drilled a small pilot hole for them to rest in place.
With the template complete we removed the old leaking piece and pulled the tie rod ends with a 19 mm wrench and vice grip. With the old rack removed we mounted the replacement rack on the board installed the tie rods ends. With the input shaft centered, we adjusted the tie rods until the grease fitting fit in the exact position of the prior rack.
Once we were satisfied with the alignment, we tightened the tie rod locking nuts and pulled the rack from the board.
We reversed the process starting with slipping the rack back through the driver side. Tightening the mounting bolts was a breeze with extra room gained by the sway bar out of the way. With all the mounting bolts tight we installed the new o-rings provided with our rack on the lines and tightened them in place starting with the pressure line and finishing with the return line. Once these lines were connected we installed the return line support clamps along the body of the rack. We slid the reservoir line in place, pushed the steering shaft on and replaced the pinch clamp bolt. After snugging the pinch clamp bolt tight we slid the cover on and secured it with a 7 mm socket on the lone retaining screw. The tie rod ends popped back into the spindle. We used our 18 mm wrench to torque them in place and line up the castle nut with the hole in the stud to slip the carter pin in place and lock things down.
With a bit of twist, turn, and pause, we slid the sway bar in place and bolted it back to the mounts on either side of the frame. Getting the end links to line up required a bit of jacking on the spindle assembly to help align the bolt through the end link holes. After tightening those bolts we topped of the system with our new Royal Purple synthetic fluid.
Purging the air from the system is easy with the car on jacks. We started the engine and turned the wheel lock to lock checking and adding fluid while also observing for leaks under the car. Once satisfied it was full and dry…there was nothing left but to drop it down and head out on the road.
Our total cost was under $160 and a Saturday afternoon. The alignment is as good as it was and we are ready to go terrorizing some curves…without any more nasty drips, leaks, and stains on our driveway!
Photos/Captions:
100-3551 Dreaded weepy rack syndrome. Believe it or not, the undercarriage on this car was factory clean just 2,500 miles ago after a full engine swap and rebuild. (This could/should be the intro pic for the article).
100-3552 Using an 18mm wrench to remove the feed and return lines from the rack. Removing the return line first gives the most room to access the pressure line.
100-3555 Using a long extension on an 11mm socket, we were easily able to access the steering shaft pinch bolt.
100-3556 The main rack mounting bolt is loose and ready to slide out of the bracket.
100-3562 Popping the tie rod end off with a pickle fork.
100-3557 Using a pair of 15mm wrenches and removing the sway bar end link bolt.
100-3558 Sliding the sway bar free of the frame.
100-3559 Working the rack out the driver side of the frame.
100-3561 mounted the old rack on a 2x4 to create a template for setting the tow on the replacement rack.
100-3563 Topping off the reservoir with Royal Purple synthetic fluid.
100-3565 This needs some photoshop work, but it is a pic of the old rack removed and could also make a good lead shot for the story if the blue blanket can be manipulated.
Source:
Parts America
http://www.partsarmerica.com
part# 22111
Royal Purple Synthetic Oils
http://www.royalpurple.com
888-382-6300
Swapping the rack & pinion in a C4
The rack first appeared in the Y body chassis as standard equipment on the 1984 Corvette. This tested and proven technology offered less weight, less moving parts, and more precision steering than systems of the past. Two version were available with the Z51 quick ration and FE soft ride cars for different driving styles. Over time, the rack has a tendency to develop leaks around the seals, and or develop performance issues resulting in loss of power steering during spirited driving and slows power assistance.
While the rack & pinion is buried deep in the front suspension, it is not that difficult of a task for the average do-it-yourselfer to swap out using only basic hand tools and a little garage space. Our rack had developed a slow leak around the bottom input shaft seal. This means the internal seals were leaking allowing excess fluid to puddle in the void behind the dust cap and steadily drip out whether while in use or just sitting in the garage. In a matter of 1,000 miles the reservoir could drain to the point the pump would growl.
Our swap started with a trip to the local Parts America. We picked up a rebuilt unit for a cool $140 out the door less the $125 core deposit. We also picked up a bottle of Royal Purple synthetic fluid to top off the reservoir once the bottom was sealed tight.
Back in the garage we jacked the car up high enough to remove the tires and have ample room to slide underneath. A large oil drain pan worked perfect for catching the excess fluid once the system was ready to drain. From the topside we used a 7mm socket to remove the fastener around the steering input shaft cover. Once that was removed we used a 11mm socked on a long extension to remove the pinch clamp bolt holding the steering shaft to the rack. The head of the bolt was pointing straight up with the steering wheel locked in the center position.
The feed and return line on the rack use a 18 mm tubing wrench. We found it best to remove the return line first to gain the most access to the pressure line. Once these lines are off the system will start draining into the catch pan. With a flathead screwdriver we released the return hose clamp and slide the return hose off the reservoir. We also slipped under the car with a 10 mm and 7 mm to release the clamp brackets retaining the return hose assembly to the rack and then lifted the entire return line assembly out of the car. If equipped with a steering cooler, we would be pulling the cooler out at this time along with this line.
Using a 15 mm wrench and socket we removed the main rack mounting bolt from the driver side of the rack followed by removing the two retaining clamp bolts on the passenger side with a 13 mm socket. At the tie rod end, we pulled the carter pin and used a 18 mm socket to remove the tie rod nut, then pounded the tie rod free with a pickle fork. We had a fork on hand, but if you don’t have one, they can be rented at your local auto parts store.
In order to get the rack out of the car you have to remove the sway bar. We used a pair of 15 mm wrenches to release the bar from the side mount brackets, then used a 15 mm socket to release the sway bar mounts from the frame rails. There are two bolts on each side that hold the sway bar mounts in place. With a bit of wiggle and twist the sway bar slid out through the driver side. With the sway bar out of the way we simply pried the rack free from the frame and twisted and turned until it slid out the driver side as well.
We took this time to spray some engine degreaser on the cross member and supporting suspension components that suffered the fate of the fluid leak mixed with road grime. This is the best time to get the area clean as there is very little access once the rack is in place.
We had recently had an alignment on this car and didn’t want to run right back down and do it again. The challenge was to get the replacement rack in the exact same adjustment as the original one. We solved this by taking a five foot long 2x4 and placing the old rack on top with the steering input centered. We drilled a 3/8†hold in the wood directly in line with the main rack frame mount support hole. Using a long 3/8†bolt, we secured the rack to the board and aligned the tie rod ends facing threads up on each end. We marked the location of the grease fittings, moved the ends, then drilled a small pilot hole for them to rest in place.
With the template complete we removed the old leaking piece and pulled the tie rod ends with a 19 mm wrench and vice grip. With the old rack removed we mounted the replacement rack on the board installed the tie rods ends. With the input shaft centered, we adjusted the tie rods until the grease fitting fit in the exact position of the prior rack.
Once we were satisfied with the alignment, we tightened the tie rod locking nuts and pulled the rack from the board.
We reversed the process starting with slipping the rack back through the driver side. Tightening the mounting bolts was a breeze with extra room gained by the sway bar out of the way. With all the mounting bolts tight we installed the new o-rings provided with our rack on the lines and tightened them in place starting with the pressure line and finishing with the return line. Once these lines were connected we installed the return line support clamps along the body of the rack. We slid the reservoir line in place, pushed the steering shaft on and replaced the pinch clamp bolt. After snugging the pinch clamp bolt tight we slid the cover on and secured it with a 7 mm socket on the lone retaining screw. The tie rod ends popped back into the spindle. We used our 18 mm wrench to torque them in place and line up the castle nut with the hole in the stud to slip the carter pin in place and lock things down.
With a bit of twist, turn, and pause, we slid the sway bar in place and bolted it back to the mounts on either side of the frame. Getting the end links to line up required a bit of jacking on the spindle assembly to help align the bolt through the end link holes. After tightening those bolts we topped of the system with our new Royal Purple synthetic fluid.
Purging the air from the system is easy with the car on jacks. We started the engine and turned the wheel lock to lock checking and adding fluid while also observing for leaks under the car. Once satisfied it was full and dry…there was nothing left but to drop it down and head out on the road.
Our total cost was under $160 and a Saturday afternoon. The alignment is as good as it was and we are ready to go terrorizing some curves…without any more nasty drips, leaks, and stains on our driveway!
Photos/Captions:
100-3551 Dreaded weepy rack syndrome. Believe it or not, the undercarriage on this car was factory clean just 2,500 miles ago after a full engine swap and rebuild. (This could/should be the intro pic for the article).
100-3552 Using an 18mm wrench to remove the feed and return lines from the rack. Removing the return line first gives the most room to access the pressure line.
100-3555 Using a long extension on an 11mm socket, we were easily able to access the steering shaft pinch bolt.
100-3556 The main rack mounting bolt is loose and ready to slide out of the bracket.
100-3562 Popping the tie rod end off with a pickle fork.
100-3557 Using a pair of 15mm wrenches and removing the sway bar end link bolt.
100-3558 Sliding the sway bar free of the frame.
100-3559 Working the rack out the driver side of the frame.
100-3561 mounted the old rack on a 2x4 to create a template for setting the tow on the replacement rack.
100-3563 Topping off the reservoir with Royal Purple synthetic fluid.
100-3565 This needs some photoshop work, but it is a pic of the old rack removed and could also make a good lead shot for the story if the blue blanket can be manipulated.
Source:
Parts America
http://www.partsarmerica.com
part# 22111
Royal Purple Synthetic Oils
http://www.royalpurple.com
888-382-6300