Quote:
Originally Posted by dford  Hello,
What all is involved in replacing the intake manifold gasket on my 83 Z28 305 Crossfire? Anything special to replace/pay special attention to?
Dan |
Dan
You can use the FelPro MS91440 gasket set. It includes both the left and right intake gaskets, the cover gasket, two gaskets for the base of the TBI units and a gasket for the distributor. You may also need to get a gasket for the EGR valve. You do not need to remove the TBI units from the intake cover to replace the intake gaskets.
Two items are no longer available new, so take care to preserve what you have. They are the water hose from the heater core to the rear of the mainfold and the EGR vaccum solenoid swithch. The EGR vaccum solenoid is mounted behind the passenger side TBI, just in front of the EGR valve.
The EGR vaccum solenoid is mounted on a stud with a nut on top. The problem here is that that stud also bolts the cover to the intake. On the two cars I have worked on, the stud has been loose on both. The nut holding the valve is on solid and it is extremely hard to get a wrench on the stud nut so you can remove the nut holding the solenoid. I have not figured out how to do this yet.
There are two or three other studs holding the TBI cover on the intake, with nuts on them tieing down other items.
The biggest problem you may have is removing the fuel lines to the throttle bodies. You have no room to work with and the flare nuts and lines are forzen in place. I have managed to round the flare nuts on both TBI cars I have worked on. After that, the only way to get the fule lines out is to cut them. This is another item that is not readily avaiable anymore.
I highly recommend that you take a lot of picture before and while you remove items. It will help you get thing back together correctly if you stop and start this work over several months.
The basic sequence is this:
1. Pulll the fuel pump relay and start the car. This will burn off some of the fuel in the TBIs and releive the pressuer in the fuel lines. After the car stalls, turn it over a few more times.
2. Remove the air cleaners and the hoses attached to the air cleaner.
3. Remove the generator backet, the generator, the AC compressor and the compressor bracket and support.
4. Remove the air valve on the right front of the passenger side. This is part of the pollition equipment.
5. Disconnect the wire harness to the TBI area: connector to the throttle position indicator on the driver's side TBI, both IAC connectors (lower right side of each TBI when viewed from the fron of the car), the connector on the top of each TBI at is connected to the injector, the coolant temp sensor conector, the ground wires under one of the stud nuts....
7. The AIR pump hose between the block and the AIR valve
6. Drain the radiator.
8. Remove the EGR vaccum solenoid. The the EGR valve.
9. Remove the PVC hose from the TEE connection back to the TBI cover plate. Note the the piece the hose is connect to has a nut on it and it unscrews to remove if from the TBI cover. Don't be suprised if this nut is loose also.
10. You will need to remove the supply fuel line from the filter on the right front of the block below the AIR pump to the passenger side TBI. You will need a 5/8" flare nut wrench and a 3/4" open wrench. The flare nut screws into a reducer that bolts into the base of the TBI.
11. Remove the return fuel line from the driver's side TBI to the hose connection by the rear of the block, under the steering wheel. Note that this line runs between the intake and the valve cover to teh back of the block where it turns down and is held by a clamp to the back of the block, below the valve cover.
(Before removing the fuel lines, I would go to the parts store and get tow brass hose fitting and screw in end caps, a few hose clamps and a foot or so of fuel line hose. Assemble a length of hose ( 2~3 inches, the hose fillting and the end cap. Make sure the connection between the end cap and the hose fitting is tight.) Use these to seal the fuel lines closed after you remove the fuel lines. You do not want the leave the fuel lines open and let gas from the tank evaporate into the air.)
12. Remove the metal vaccum hose to the power brake booster. Remove the vaccum hoses from the vaccum port at the left rear of the TBI cover.
13. If you have curise control, remove the throttle cable and support attached to the right TBI. The cable is held on by a clip. I used a small screw driver to pry the clip open and a pair of needle nose pliers to move th clip to its release point.
14. Remove the transmission detent(?) cable. You will need to lossen it and slide if forward to loosen it, and then you can disconnect it. Remove the throttle cable from the rear TBI.
15. Now you can remove the 14 bolts and studs around the perimeter of the TBI cover. Pay attention to their positions as some of the studs and bolts are different sizes. Before trying to pull the cover, there are two more items to remove. The are the shafts that the air cleaner covers are bolted to. They rise out of each TBI unit. One they are out, give the cover a few light taps. Then you should be able to remove it. Be careful not to get gasket parts into the intake manifold.
16. Remove all the spark plug wires from the distributor cap. Best to make a diagram and lable the wires before disconnecting any of them.
17. Remove the distributor hold down bolt and the distributor. There is a way to mark the distributor position prior to removing it so you can reinstall it in the correct position. Sorry, but I don't have that info handy.
18. Remove the bolts holding the intake manifold. Note that a few of these are outside the manifold, and incluce the bolts holding down the motor lifting lugs on the passenger rear and drive front side of the mainfold. You may need to remove the thermostate cover to remove the bolts on the front lifting lugs. The hardest two bolts to get to are the two at the rear of the intake, one on each side. Now you should be albe to remove the intake manifold.
19. Remove the gasket material as necessary.
20. Reassemble in reverse order.
Let me know if you need any photos or nut sizes. I have an intake manifold and cover, with the TBIs, that I pulled off an 83 Firebird CFI in junk yard a few moths ago. I also have most of the items removed in preperation for pulling the cover and intake on my 82 CFI. I stopped last summer after I rounded the nuts on the fuel lines. I have since cut the lines out and intend on replacing them this summer.
