How to remove pre-cat?
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HyperREV.com
Joined: Mar 2001
Posts: 1,162
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From: Oregon
hey snoopster i got this off the teamfc3s board, from a link to one of the members on here (thanks by the way).
Removing the turbo unit from a Turbo II (Rob Rike)
· 1. Remove Intercooler
· 2. Remove Air Box
· 3. Remove Air pump
· 4. Go ahead and disconnect lower radiator hose to drain radiator and get hose out of the way for now.
· 5. Remove the BAC valve and move it out of the way .
· 6. Remove the Air Control Valve and be careful not to lose the reed valve looking thing contained in it. If it does fall off, when reinstalling the small round piece goes into the engine side.
· 7. Jack the car up and get down to the dirty task of removing the heat shields. (DISCLAIMER: They are a royal pain in the *** and I cut or broke the majority of mine off) The heat shield around the turbo will not come off until the pre-converter is removed and you can slide it out from underneath the car.
· 8. Unhook the split air pipe running from the Main Cat to the engine. It is secured to the engine by two nuts.
· 9. I went ahead and disconnected the middle exhaust system mounts and the rear ones since the pre-converter has to come off next. It will give you extra room to wedge it out.
· 10. Once the mounts are loose, take a 17mm deep well socket and remove the nuts connecting the pre-cat to the exhaust pipe.
· 11. Now it is time to remove the pre-cat. It is held in place by 3 bolts running to the Turbo's turbine housing. With the heat shields off, one is accessible from the top of the engine with a 14mm wrench (not enough room for a socket). The other 2 are accessible from under the engine. With one, I used some 14mm socket and extension combination and got to it fairly easy. The last one I used the same combination along with every extension bar I had plus a universal joint right behind the socket. I went up along the tranny tunnel at an angle and worked the socket onto it. Saves much frustration and scraped knuckles.
· 12. Make sure you have unplugged the O2 sensor and prepare to lower the cat. It is heavier than it looks so don't drop it on your head.
· 13. Now it is time to disconnect the assorted coolant and oil lines to the turbo.
· a. (TIP- The tire iron in the back of the car is the perfect size to fit the nut on the coolant pipe flange bolt) Disconnect the flange bolt and then disconnect the 2 nuts that secure the pipe to the engine.
· b. Disconnect the oil line fitting with a 17 mm wrench and a pair of vise grips on the other bolt.
· c. Disconnect the oil drain line. It is a braided hose with 2 10mm bolts securing it to the engine mounting.
· d. Finally, disconnect the coolant return line. It is a rubber hose running into what looks to be the water pump. It is a 90 degree hose and now is a good time to replace it.
· 14. With everything presumably loose or disconnected, it is time to remove the turbo. It is held in place with 4 14mm bolts to the exhaust manifold. A combination of 14mm socket and extension bars with get the right to bolts from above the car and then crawl under and remove the left two with a wrench.
· 15. You should now be able to lift the turbo up and out of the engine. It takes some twisting and wedging but trust me, that is the only way that bastard is coming out of there.
Installing the Turbo unit in a Turbo II (Rob Rike)
· 1. Sit the turbo back on top of the exhaust housing and make sure that the compressor intake pipe lines up and does not hit the engine anywhere, etc. Assuming all is correct, go ahead and put the two right hand side bolts of the turbo on and finger tighten them. Then get under the car and finger tighten the left two on and go ahead and snug down the lower left one. Get back up top and snug down the upper right one and then back under for the upper left one. You guessed it, back up to the top and tighten the lower right one and that baby is back on.
· 2. Now is a good time to go under the car and insert the main heat shield up in its approximate position. It is almost impossible to do from above the car.
· 3. Go ahead and put the pre-cat back on the car and bolt it down tight.
· 4. Rehook all of the hoses to the turbo that you disconnected. When reconnecting the coolant line that faces the passenger side of the car, make sure you connect the end that goes to the engine first!!!!! (Trust me here, I busted the bolts off the intake manifold end while trying to torque these down to stop a leak. The flange bolt is a lot stronger than the 6.0 X 1.0 mm bolt studs. If for some reason you do break one along the way, you should be able to get it out with a pair of vise grips, it is not very tight. Replace it with a 6.0 X 1.0 bolt of appropriate length)
· 5. Go ahead and connect the oil lines and other fittings to the turbo (I used a little liquid Teflon tape on the oil pipe fitting)
· 6. Re-connect the hoses that you removed and go ahead and refill and air bleed the radiator.
· 7. Go underneath, reconnect the exhaust pipe to the pre-cat and re-attach all of the system hangars.
· 8. Double check all of your fittings and make sure all hoses are tight. Watch that coolant pipe going to the turbo for leaks.
· 9. Since the Turbo has probably been removed to be rebuilt, I would go ahead and remove the EGI fuse and crank the engine over for several seconds to get some oil into the turbo bearings. You don't want to start it up and have that fast idle thing kick it up to 3,000 rpm's on dry bearings. For that matter, when you do start it you may want to leave it in first to prevent the fast idle.
10. Once the engine starts to warm up a bit the turbo will probably start to smoke under the hood. I am told this is normal as new oil used during rebuilding burns off the housings and as the solvents heat up and burn off. Just keep an eye out for oil and coolant leaks and let it idle for about 15 minutes before driving it. This way you can be sure the bearings have plenty of oil.
snoopster - extra note, i took off some of the hangers off the exhaust so i could pivot it out with my feet for extra room, its very tight squeez i actually bent the bolts alittle, but got it off without taking off the whole thing.
good luck, and be patient.
brandon
Removing the turbo unit from a Turbo II (Rob Rike)
· 1. Remove Intercooler
· 2. Remove Air Box
· 3. Remove Air pump
· 4. Go ahead and disconnect lower radiator hose to drain radiator and get hose out of the way for now.
· 5. Remove the BAC valve and move it out of the way .
· 6. Remove the Air Control Valve and be careful not to lose the reed valve looking thing contained in it. If it does fall off, when reinstalling the small round piece goes into the engine side.
· 7. Jack the car up and get down to the dirty task of removing the heat shields. (DISCLAIMER: They are a royal pain in the *** and I cut or broke the majority of mine off) The heat shield around the turbo will not come off until the pre-converter is removed and you can slide it out from underneath the car.
· 8. Unhook the split air pipe running from the Main Cat to the engine. It is secured to the engine by two nuts.
· 9. I went ahead and disconnected the middle exhaust system mounts and the rear ones since the pre-converter has to come off next. It will give you extra room to wedge it out.
· 10. Once the mounts are loose, take a 17mm deep well socket and remove the nuts connecting the pre-cat to the exhaust pipe.
· 11. Now it is time to remove the pre-cat. It is held in place by 3 bolts running to the Turbo's turbine housing. With the heat shields off, one is accessible from the top of the engine with a 14mm wrench (not enough room for a socket). The other 2 are accessible from under the engine. With one, I used some 14mm socket and extension combination and got to it fairly easy. The last one I used the same combination along with every extension bar I had plus a universal joint right behind the socket. I went up along the tranny tunnel at an angle and worked the socket onto it. Saves much frustration and scraped knuckles.
· 12. Make sure you have unplugged the O2 sensor and prepare to lower the cat. It is heavier than it looks so don't drop it on your head.
· 13. Now it is time to disconnect the assorted coolant and oil lines to the turbo.
· a. (TIP- The tire iron in the back of the car is the perfect size to fit the nut on the coolant pipe flange bolt) Disconnect the flange bolt and then disconnect the 2 nuts that secure the pipe to the engine.
· b. Disconnect the oil line fitting with a 17 mm wrench and a pair of vise grips on the other bolt.
· c. Disconnect the oil drain line. It is a braided hose with 2 10mm bolts securing it to the engine mounting.
· d. Finally, disconnect the coolant return line. It is a rubber hose running into what looks to be the water pump. It is a 90 degree hose and now is a good time to replace it.
· 14. With everything presumably loose or disconnected, it is time to remove the turbo. It is held in place with 4 14mm bolts to the exhaust manifold. A combination of 14mm socket and extension bars with get the right to bolts from above the car and then crawl under and remove the left two with a wrench.
· 15. You should now be able to lift the turbo up and out of the engine. It takes some twisting and wedging but trust me, that is the only way that bastard is coming out of there.
Installing the Turbo unit in a Turbo II (Rob Rike)
· 1. Sit the turbo back on top of the exhaust housing and make sure that the compressor intake pipe lines up and does not hit the engine anywhere, etc. Assuming all is correct, go ahead and put the two right hand side bolts of the turbo on and finger tighten them. Then get under the car and finger tighten the left two on and go ahead and snug down the lower left one. Get back up top and snug down the upper right one and then back under for the upper left one. You guessed it, back up to the top and tighten the lower right one and that baby is back on.
· 2. Now is a good time to go under the car and insert the main heat shield up in its approximate position. It is almost impossible to do from above the car.
· 3. Go ahead and put the pre-cat back on the car and bolt it down tight.
· 4. Rehook all of the hoses to the turbo that you disconnected. When reconnecting the coolant line that faces the passenger side of the car, make sure you connect the end that goes to the engine first!!!!! (Trust me here, I busted the bolts off the intake manifold end while trying to torque these down to stop a leak. The flange bolt is a lot stronger than the 6.0 X 1.0 mm bolt studs. If for some reason you do break one along the way, you should be able to get it out with a pair of vise grips, it is not very tight. Replace it with a 6.0 X 1.0 bolt of appropriate length)
· 5. Go ahead and connect the oil lines and other fittings to the turbo (I used a little liquid Teflon tape on the oil pipe fitting)
· 6. Re-connect the hoses that you removed and go ahead and refill and air bleed the radiator.
· 7. Go underneath, reconnect the exhaust pipe to the pre-cat and re-attach all of the system hangars.
· 8. Double check all of your fittings and make sure all hoses are tight. Watch that coolant pipe going to the turbo for leaks.
· 9. Since the Turbo has probably been removed to be rebuilt, I would go ahead and remove the EGI fuse and crank the engine over for several seconds to get some oil into the turbo bearings. You don't want to start it up and have that fast idle thing kick it up to 3,000 rpm's on dry bearings. For that matter, when you do start it you may want to leave it in first to prevent the fast idle.
10. Once the engine starts to warm up a bit the turbo will probably start to smoke under the hood. I am told this is normal as new oil used during rebuilding burns off the housings and as the solvents heat up and burn off. Just keep an eye out for oil and coolant leaks and let it idle for about 15 minutes before driving it. This way you can be sure the bearings have plenty of oil.
snoopster - extra note, i took off some of the hangers off the exhaust so i could pivot it out with my feet for extra room, its very tight squeez i actually bent the bolts alittle, but got it off without taking off the whole thing.
good luck, and be patient.
brandon
Twisted Girl Chaser
Joined: Sep 2001
Posts: 348
Likes: 0
From: mountain home idaho
Shouldn't be hard on the TII's either
That procedure is to remove the turbo, the precat is only three at the top and two at the bottom along with the O2 sensor. My problem is gettting the three at the turbo loose, they won't budge. Today I'm going to try a 6 point 14mm socket on a breaker bar and a peice of pipe or something on the bar, I need my dp installed.
Eggs are like fowl cheese
Joined: Mar 2001
Posts: 574
Likes: 0
From: Daniel Island, SC
Yea I actually had to use a breaker bar on mine too. WOW those suckers were on there tight. My method was a foot and a half long breaker bar. I used my feet to turn it. I could not get it to budge with my arms, but with my legs it broke loose no problem. 
