Clutch replacement help - remove trans, bellhousing, headers?? - ZR-1 Net Registry Forums

emmvette · 11-13-2015

Time to work on the clutch, it's pretty much toast and undriveable. Car is a '90. Put it up on the lift today and am sort of stuck before starting. Took apart everything inside and moved to the underneath - with my cars mods / setup, I don't see how to get to the clutch easily. See pics below, does anybody else have old headers like this (they are one piece, looks like they were fabricated to the existing CATS). I have been led to believe these headers where made by Calloway.

I have two basic questions -

1. After the ZF is removed, does anybody know if the bellhousing will move 3" toward the rear of the car without hitting the fiberglass tunnel up top? It looks like it will hit the tunnel and that it won't come out. It would be very close.

2. Standing at the rear of the car underneath looking up at the bell housing (looking toward the front end), can the bell housing rotate clockwise a bit?

I'm guessing the engine was put in with the headers/cats and bell housing all installed. The header bolts are not all accessible from the top or bottom, and the headers are one piece including the CATS. So the bell housing will not drop straight down because it will hit the CATs.... But the CATS can't come off without pulling the engine to get to the header bolts.

If the bell housing will slide back 3 -3.25", then it will clear the CATs and it can be lowered and I can continue. There is only about 1/8" clearance between the CATs and the bell housing, maybe a 1/16" more on the driver's side. Is this how the ZR-1 left the factory or are my CATS in a different place than normal.

My question #2 is because there is an aluminum bump out on the bell housing on the drivers side near where the slave cylinder is that also won't clear the CAT unless I can rotate the bell housing clockwise about 30 - 40 degrees.

Any thoughts on this? Any Callaway owners that have shorty one piece headers and CATs that might have run into this? I really don't want to pull the engine just work on the clutch. I was already feeling like I didn't have time for the "small" project. I don't know that I can take on that large of a project - especially this time of the year with an uninsulated garage - its getting cold outside....

5ABI VT · 11-13-2015

Those appear to be factory manifolds and cats. I did the whole shebang just last winter ill try and find the thread. pretty sure once the tranny is pulled out there is room to move the bellhousing back and out. Need a memory refresh before I post more

emmvette · 11-13-2015

They are not factory, I should put it back in the air and take a photo more from the front, they are short headers, the header flanges are extremely thick about 1/4" +

They were put on the car at Lingenfelter in '95 before long tube headers became the way to go.

Regardless, I would appreciate your thoughts / experience!

tccrab · 11-13-2015

Looks to be plenty of room to get the trans out.
I'm going to guess you will have to cut the passenger side exhaust to drop the rest of the exhaust system, but once it's out of the way, just unbolt the transmission and drop it out.

'Crabs

Pete · 11-13-2015

You have to remove the exhaust (not manifolds/headers) and your throttle body snorkle.

Once you take the C-beam off start to lower the trans jack to have access to trans screws (5) then start tilt and pull you have to clear shifter put it in 3rd gear no worries motor can tilt without hurting anything.

Once trans is out the motor will be tilted n bell housing will come off.

I kept this short hoping you know to take off the obvious i.e. slave cylinder,cover plate etc,

If you need or have more detailed questions just ask.
Pete

Dynomite · 11-14-2015

Like Pete says

TRANSMISSION
Post 35 - Pilot Bearing
Post 36 - See Item #6 ZR-1 Transmission Install and Lift Tricks

6. Clutch Replacement TIPS (REMOVAL)
1. Drop the exhaust manifolds and release the exhaust system from the two transmission hangers and differential hangers (Or drop exhaust pipes after CATS only). Drag exhaust out of the way.
2. Place jack under oil pan with 2x4 between oil pan and jack plate. Jack up a tad and go to item 3.
3. Remove "C" Frame Bolts and remove "C" Frame. Have in hand ZF Doc "C" Frame Plates for the re-installation of "C" Frame Later.
4. After "C" frame is removed, Lower engine (jack under oil pan) a few inches.
5. Remove universal joint on drive shaft to rear by differential. Mark drive shaft so you get it installed for possible correct balance later. Pull drive shaft from transmission. Beware of transmission fluid leaking all over once drive shaft is removed from transmission.
6. I would drain transmission fluid before I start this job and replace with new Castrol TWS 10W-60 later after reinstallation of transmission. Get yourself a 17 mm Allen Wrench also for transmission plugs. Castrol TWS 10W-60 I just buy Castrol TWS 10W-60 as well as Amsoil 10W-40 (Engine) online. Transmission ZF S6-40 takes 4.4 pints or 2.1 Liters of Castrol TWS 10W-60.
7. On top side remove shifter knob, and shifter boot so you can lower transmission later with shifter attached. The lower you can get the rear of the engine the better but make sure your cam covers do not hit brake booster of fire wall as you lower rear of engine a bit.
8. Remove clutch slave cylinder and leave it hang.
9. Remove transmission bolts (jack under oil pan and with another jack under transmission (the best is transmission jack), use BIG flat head screw driver between transmission and bell housing as it takes some pressure as you jack up and down a bit to free the transmission from the pilot bearing. There are some electrical connections on transmission you remove before pulling the transmission free.
10. Remove bell housing bolts. Pull Bell housing off but watch the throw out bearing as it stays with the pressure plate. The black label and blue label transmissons take different throw out bearings.
11. Remove pressure plate bolts being carefull to loosen bolts equally all around the pressure plate a step at a time. Do not just remove one bolt at a time. Remove pressure plate (it will fall off once all bolts are removed. The clutch plate will also fall off.
12. You might want to now inspect the pressure plate surface and surface of the flywheel.
13. You also want to remove the pilot bearing (there are pilot bearing pullers if it will not come out with flat screw driver wedging it out). I would have a new pilot bearing/bushing on hand.

Post 37 - Vibration Issues Diagnosis
Post 38 - Throwout Bearings and Clutch Forks
Post 39 - C4 Beam Plates and Installation

emmvette · 11-16-2015

Thanks, gents, it all came out. Not without struggles, but what fun would that have been. Next up, get it all cleaned up, some machining, and a few parts.

spork2367 · 11-17-2015

Quote:

Originally Posted by emmvette

They are not factory, I should put it back in the air and take a photo more from the front, they are short headers, the header flanges are extremely thick about 1/4" +

They were put on the car at Lingenfelter in '95 before long tube headers became the way to go.

Regardless, I would appreciate your thoughts / experience!

What leads you to believe this? From the bottom they look like the factory one piece units (actually short headers).

emmvette · 11-23-2015

Thanks for the encouragement, gents! It did come out as you said it would. Just needed to do a little tweaking under the oil pan as suggested and some patience.

New clutch back in and it seems to grab well, at least in and out of the driveway. Didn't want to scare the neighbors too much with the exhaust off. I'll have time to finish it up next week. The one thing that was a little more difficult than expected was removing the boot on the shifter. Not sure if it's the same all years. Mine is a '90. Is there a trick to getting it reinstalled? It basically sits alongside a seam on the left side (driver's side) as you are sitting in the seat facing forward. Look like a bear to get it back on due to the lack of room on the left side. I don't want to tear it during the reinstall.

11-13-2015	#1
emmvette Join Date: Jul 2013 Location: Central Iowa Posts: 188	Clutch replacement help - remove trans, bellhousing, headers?? Time to work on the clutch, it's pretty much toast and undriveable. Car is a '90. Put it up on the lift today and am sort of stuck before starting. Took apart everything inside and moved to the underneath - with my cars mods / setup, I don't see how to get to the clutch easily. See pics below, does anybody else have old headers like this (they are one piece, looks like they were fabricated to the existing CATS). I have been led to believe these headers where made by Calloway. I have two basic questions - 1. After the ZF is removed, does anybody know if the bellhousing will move 3" toward the rear of the car without hitting the fiberglass tunnel up top? It looks like it will hit the tunnel and that it won't come out. It would be very close. 2. Standing at the rear of the car underneath looking up at the bell housing (looking toward the front end), can the bell housing rotate clockwise a bit? I'm guessing the engine was put in with the headers/cats and bell housing all installed. The header bolts are not all accessible from the top or bottom, and the headers are one piece including the CATS. So the bell housing will not drop straight down because it will hit the CATs.... But the CATS can't come off without pulling the engine to get to the header bolts. If the bell housing will slide back 3 -3.25", then it will clear the CATs and it can be lowered and I can continue. There is only about 1/8" clearance between the CATs and the bell housing, maybe a 1/16" more on the driver's side. Is this how the ZR-1 left the factory or are my CATS in a different place than normal. My question #2 is because there is an aluminum bump out on the bell housing on the drivers side near where the slave cylinder is that also won't clear the CAT unless I can rotate the bell housing clockwise about 30 - 40 degrees. Any thoughts on this? Any Callaway owners that have shorty one piece headers and CATs that might have run into this? I really don't want to pull the engine just work on the clutch. I was already feeling like I didn't have time for the "small" project. I don't know that I can take on that large of a project - especially this time of the year with an uninsulated garage - its getting cold outside.... Last edited by emmvette; 11-13-2015 at 10:20 PM.

11-13-2015	#3
emmvette Join Date: Jul 2013 Location: Central Iowa Posts: 188	Re: Clutch replacement help - remove trans, bellhousing, headers?? They are not factory, I should put it back in the air and take a photo more from the front, they are short headers, the header flanges are extremely thick about 1/4" + They were put on the car at Lingenfelter in '95 before long tube headers became the way to go. Regardless, I would appreciate your thoughts / experience!

11-13-2015	#4
tccrab Join Date: Oct 2004 Location: Folsom CA Posts: 1,663	Re: Clutch replacement help - remove trans, bellhousing, headers?? Looks to be plenty of room to get the trans out. I'm going to guess you will have to cut the passenger side exhaust to drop the rest of the exhaust system, but once it's out of the way, just unbolt the transmission and drop it out. 'Crabs

11-13-2015	#5
Pete Join Date: Dec 2003 Location: Chicagoland,IL Posts: 2,667	Re: Clutch replacement help - remove trans, bellhousing, headers?? You have to remove the exhaust (not manifolds/headers) and your throttle body snorkle. Once you take the C-beam off start to lower the trans jack to have access to trans screws (5) then start tilt and pull you have to clear shifter put it in 3rd gear no worries motor can tilt without hurting anything. Once trans is out the motor will be tilted n bell housing will come off. I kept this short hoping you know to take off the obvious i.e. slave cylinder,cover plate etc, If you need or have more detailed questions just ask. Pete __________________ '91 #1635 PoloGreen 350 LT5 11.09 @ 129.27 11.04 @ 128.86 474RWHP 400RWTQ http://www.youtube.com/watch?v=SFNFOhGGlR4 http://www.youtube.com/watch?v=ZlRIOMwaDYY https://sites.google.com/site/peteszr1garage

11-16-2015	#7
emmvette Join Date: Jul 2013 Location: Central Iowa Posts: 188	Re: Clutch replacement help - remove trans, bellhousing, headers?? Thanks, gents, it all came out. Not without struggles, but what fun would that have been. Next up, get it all cleaned up, some machining, and a few parts.

11-13-2015	#2
5ABI VT Join Date: Jun 2013 Location: Toronto Posts: 780	Re: Clutch replacement help - remove trans, bellhousing, headers?? Those appear to be factory manifolds and cats. I did the whole shebang just last winter ill try and find the thread. pretty sure once the tranny is pulled out there is room to move the bellhousing back and out. Need a memory refresh before I post more

11-14-2015	#6
Dynomite Join Date: Aug 2009 Location: South Dakota/California Posts: 3,816	Re: Clutch replacement help - remove trans, bellhousing, headers?? Like Pete says TRANSMISSION Post 35 - Pilot Bearing Post 36 - See Item #6 ZR-1 Transmission Install and Lift Tricks 6. Clutch Replacement TIPS (REMOVAL) 1. Drop the exhaust manifolds and release the exhaust system from the two transmission hangers and differential hangers (Or drop exhaust pipes after CATS only). Drag exhaust out of the way. 2. Place jack under oil pan with 2x4 between oil pan and jack plate. Jack up a tad and go to item 3. 3. Remove "C" Frame Bolts and remove "C" Frame. Have in hand ZF Doc "C" Frame Plates for the re-installation of "C" Frame Later. 4. After "C" frame is removed, Lower engine (jack under oil pan) a few inches. 5. Remove universal joint on drive shaft to rear by differential. Mark drive shaft so you get it installed for possible correct balance later. Pull drive shaft from transmission. Beware of transmission fluid leaking all over once drive shaft is removed from transmission. 6. I would drain transmission fluid before I start this job and replace with new Castrol TWS 10W-60 later after reinstallation of transmission. Get yourself a 17 mm Allen Wrench also for transmission plugs. Castrol TWS 10W-60 I just buy Castrol TWS 10W-60 as well as Amsoil 10W-40 (Engine) online. Transmission ZF S6-40 takes 4.4 pints or 2.1 Liters of Castrol TWS 10W-60. 7. On top side remove shifter knob, and shifter boot so you can lower transmission later with shifter attached. The lower you can get the rear of the engine the better but make sure your cam covers do not hit brake booster of fire wall as you lower rear of engine a bit. 8. Remove clutch slave cylinder and leave it hang. 9. Remove transmission bolts (jack under oil pan and with another jack under transmission (the best is transmission jack), use BIG flat head screw driver between transmission and bell housing as it takes some pressure as you jack up and down a bit to free the transmission from the pilot bearing. There are some electrical connections on transmission you remove before pulling the transmission free. 10. Remove bell housing bolts. Pull Bell housing off but watch the throw out bearing as it stays with the pressure plate. The black label and blue label transmissons take different throw out bearings. 11. Remove pressure plate bolts being carefull to loosen bolts equally all around the pressure plate a step at a time. Do not just remove one bolt at a time. Remove pressure plate (it will fall off once all bolts are removed. The clutch plate will also fall off. 12. You might want to now inspect the pressure plate surface and surface of the flywheel. 13. You also want to remove the pilot bearing (there are pilot bearing pullers if it will not come out with flat screw driver wedging it out). I would have a new pilot bearing/bushing on hand. Post 37 - Vibration Issues Diagnosis Post 38 - Throwout Bearings and Clutch Forks Post 39 - C4 Beam Plates and Installation __________________ Clickable links On Iphone Touchable Links -Solutions- LT5 Modifications/Rebuild Tricks Low Mileage ZR-1 Restoration 1990 Corvette (L98) Modifications LT5 Eliminated Systems LT5 Added Systems LT5/ZR-1 Fluids 1995 LT5 SPECIFIC TOP END REBUILD TRICKS Last edited by Dynomite; 11-14-2015 at 02:37 AM.

11-23-2015	#9
emmvette Join Date: Jul 2013 Location: Central Iowa Posts: 188	Re: Clutch replacement help - remove trans, bellhousing, headers?? Thanks for the encouragement, gents! It did come out as you said it would. Just needed to do a little tweaking under the oil pan as suggested and some patience. New clutch back in and it seems to grab well, at least in and out of the driveway. Didn't want to scare the neighbors too much with the exhaust off. I'll have time to finish it up next week. The one thing that was a little more difficult than expected was removing the boot on the shifter. Not sure if it's the same all years. Mine is a '90. Is there a trick to getting it reinstalled? It basically sits alongside a seam on the left side (driver's side) as you are sitting in the seat facing forward. Look like a bear to get it back on due to the lack of room on the left side. I don't want to tear it during the reinstall.