M60 Intake Manifold Re-Seal

[stargazer_61]

Procedure for Intake Manifold Gasket Re-Seal. Thanks to Whit and Winfred for their help with the injector harness removal.

M60 owners know of this issue if they have studied the archives of this board. Winfred and Bill R. have posted pictures of the culprit parts, such as the PCV plate. Here are step-by-step instructions for removal of the intake and replacing the gaskets.

1) Disconnect the battery
2) Remove the engine cover and the ignition coil covers.
3) Disconnect the ignition coils by pulling out on the silver retaining clips, then lifting up on the coil connector. Leave them hanging.
4) Remove the air intake boot from the air box and the throttle assembly.
5) Pull the air regulating valve from the throttle housing. Silver, cylindrical shaped. There is a rubber bracket holding it to the accelerator cable bracket. Refer to http://www.realoem.com/bmw/showparts...84&hg=13&fg=15
6) Disconnect the throttle cables from the throttle assembly. You can try to remove the two T30 torx bolts that hold the bracket to the throttle assembly. I had no luck here, so just pinch the plastic tabs and work the cables out through the slots. Lay the cables over by the brake fluid reservoir.
7) Put towels underneath the input and return fuel lines and disconnect them from the fuel rail. The return line is a beast to get off, as it is really tight in there. I just cut mine and replaced it new.
8) Disconnect two hoses on the underside of the throttle assembly. These are easily accessed.
9) Remove the injector harness connections from each cylinder bank. There are three for each bank. Label them appropriately, as they will be moved around a lot. Just pinch the wire clips and lift up to disconnect.
10) Disconnect the connector to the throttle assembly, on the passenger side. There may be a similar, three-pole connector that is hanging there loose. I do not know what it is used for. Label both so that you know which one is used, if your car was set up like mine.
11) Disconnect the sensor connector from the intake manifold. It is at the front side of the manifold, on the passenger side.
12) Remove four 10mm hex nuts, two on each side, from the injector harness wire boxes.
13) Remove the injector harnesses. I tried to use a dentists pick to loosen the wire spring clips, but with no success. Per Whit’s suggestion, I used a large, flat blade screwdriver. Wedge it between the harness box and the fuel rail and ever so gently apply pressure to loosen the connection to the injectors. Work one injector at a time so as to not damage the plastic ears. Lay the driver side harness over by the air box to keep it out of the way. It remains attached to the passenger side harness.
14) Remove the two 10mm plastic nuts that hold the coolant overflow tank to the firewall. There is no need to remove the tank, just loosen it and let it hang there.
15) Remove the ten, 10mm nuts that hold the intake manifold to the engine. Use needle nose pliers to pull the nuts up, so they don’t fall down and get lost. Also pull out the ten sleeves that line the intake up on the mounting studs.
16) If possible, have an assistant hold the coolant overflow tank up out of the way while you lift off the intake manifold. It comes off with the fuel rail and injectors still attached. There is no reason to remove the injectors unless you want to replace the o-rings while you are in there.
17) Lift up on the manifold from the driver side, then slide it toward the firewall to disconnect the oil pipe from the PCV plate. There is a metal bracket that is on the end of the oil pipe that you just lift up on with a flat blade screwdriver and slide back. It is tight in there, but doable. Remove the manifold from the engine as an assembly and place on a clean work surface.
18) Now is a good time to get out the shop vac and clean out the debris in the valley. Most of the stuff in mine was just flaked off cosmolene from the valve covers. You will want to get all the crud out of there so that it does not fall into the valve train.
19) Clean the surface where the manifold mates with the heads using a lint free cloth.
20) Time to disassemble the intake manifold. As per previous posts, the T30 bolts will most likely be tight, and the heads may strip when you try to loosen them. If you had luck getting off the Bowden cable bracket from the throttle assembly, then good for you. I had to bend the ear of the bracket to get Vise-Grip pliers in there to get the bolt loose. In fact, just about all the bolts had to be Vise-Gripped loose. You can replace them with M6 hex head bolts.
21) Remove the six T30 bolts from the throttle assembly and the seven T30 bolts from the PCV plate so you can replace the gaskets.
22) The front and rear gaskets look similar, but the front side one has a slight indent on the bottom side. They will fit perfectly into the slots in the intake, so be sure to mark which gasket is front and rear.
23) Install a new PCV plate and cap along with the gasket. The cap is purchased separately. The PCV plate will come with a new o-ring for the oil pipe.
24) Replace the four gaskets on the underside of the intake after cleaning the mating surface.
25) When installing the intake, make sure that the oil pipe is reconnected to the PCV plate. To do this, push the pipe as far forward as possible, then lay the intake into the engine, pushing it toward the back.
26) The injector wiring harness connectors get moved around a lot. Be sure that you have them secured out of the way so that they can be routed back for installation.
27) Work the oil pipe into position in front of the nipple of the PCV plate. Use a flat blade screw driver to push the pipe rearward so that the firewall end engages with the PCV plate, then work the clamp into place, so that the tab locks over the ridge of the plastic.
28) Install the ten alignment sleeves, then the ten nuts for the intake manifold. Torque it to 11 ft. lbs. from the inside out, alternating sides. After torquing the nuts, go back and retorque, just to be sure.
29) Install the injector harnesses. One of the connectors on mine turned a little so I lifted it back off and aligned it prior to pressing it into place. It takes just a little push to get it to lock in.
30) The remainder of installation is the reverse of the removal.
31) Upon first restart, turn the key to position two and let it sit there for a few seconds before trying to start it. Most, if not all, of the fuel dumped out of the fuel rail and the system needs to re-pressurize. It will run rough for a minute, then smooth out.
32) Drive and check for fuel leaks.

As a side note, this cleared my 1221 fault code that I thought was an O2 sensor. Cold starting is much quieter and it idles smoother.

[Bill R.]

remove it as well as after, otherwise garbage tends to fall in as your lifting the manifold off, where it builds up between the heads and the manifold..
Also feel free to sprinkle some of these pics in there to break up the text some if you like.

Procedure for Intake Manifold Gasket Re-Seal. Thanks to Whit and Winfred for their help with the injector harness removal.

M60 owners know of this issue if they have studied the archives of this board. Winfred and Bill R. have posted pictures of the culprit parts, such as the PCV plate. Here are step-by-step instructions for removal of the intake and replacing the gaskets.

1) Disconnect the battery
2) Remove the engine cover and the ignition coil covers.
3) Disconnect the ignition coils by pulling out on the silver retaining clips, then lifting up on the coil connector. Leave them hanging.
4) Remove the air intake boot from the air box and the throttle assembly.
5) Pull the air regulating valve from the throttle housing. Silver, cylindrical shaped. There is a rubber bracket holding it to the accelerator cable bracket. Refer to http://www.realoem.com/bmw/showparts...84&hg=13&fg=15
6) Disconnect the throttle cables from the throttle assembly. You can try to remove the two T30 torx bolts that hold the bracket to the throttle assembly. I had no luck here, so just pinch the plastic tabs and work the cables out through the slots. Lay the cables over by the brake fluid reservoir.
7) Put towels underneath the input and return fuel lines and disconnect them from the fuel rail. The return line is a beast to get off, as it is really tight in there. I just cut mine and replaced it new.
8) Disconnect two hoses on the underside of the throttle assembly. These are easily accessed.
9) Remove the injector harness connections from each cylinder bank. There are three for each bank. Label them appropriately, as they will be moved around a lot. Just pinch the wire clips and lift up to disconnect.
10) Disconnect the connector to the throttle assembly, on the passenger side. There may be a similar, three-pole connector that is hanging there loose. I do not know what it is used for. Label both so that you know which one is used, if your car was set up like mine.
11) Disconnect the sensor connector from the intake manifold. It is at the front side of the manifold, on the passenger side.
12) Remove four 10mm hex nuts, two on each side, from the injector harness wire boxes.
13) Remove the injector harnesses. I tried to use a dentists pick to loosen the wire spring clips, but with no success. Per Whit’s suggestion, I used a large, flat blade screwdriver. Wedge it between the harness box and the fuel rail and ever so gently apply pressure to loosen the connection to the injectors. Work one injector at a time so as to not damage the plastic ears. Lay the driver side harness over by the air box to keep it out of the way. It remains attached to the passenger side harness.
14) Remove the two 10mm plastic nuts that hold the coolant overflow tank to the firewall. There is no need to remove the tank, just loosen it and let it hang there.
15) Remove the ten, 10mm nuts that hold the intake manifold to the engine. Use needle nose pliers to pull the nuts up, so they don’t fall down and get lost. Also pull out the ten sleeves that line the intake up on the mounting studs.
16) If possible, have an assistant hold the coolant overflow tank up out of the way while you lift off the intake manifold. It comes off with the fuel rail and injectors still attached. There is no reason to remove the injectors unless you want to replace the o-rings while you are in there.
17) Lift up on the manifold from the driver side, then slide it toward the firewall to disconnect the oil pipe from the PCV plate. There is a metal bracket that is on the end of the oil pipe that you just lift up on with a flat blade screwdriver and slide back. It is tight in there, but doable. Remove the manifold from the engine as an assembly and place on a clean work surface.
18) Now is a good time to get out the shop vac and clean out the debris in the valley. Most of the stuff in mine was just flaked off cosmolene from the valve covers. You will want to get all the crud out of there so that it does not fall into the valve train.
19) Clean the surface where the manifold mates with the heads using a lint free cloth.
20) Time to disassemble the intake manifold. As per previous posts, the T30 bolts will most likely be tight, and the heads may strip when you try to loosen them. If you had luck getting off the Bowden cable bracket from the throttle assembly, then good for you. I had to bend the ear of the bracket to get Vise-Grip pliers in there to get the bolt loose. In fact, just about all the bolts had to be Vise-Gripped loose. You can replace them with M6 hex head bolts.
21) Remove the six T30 bolts from the throttle assembly and the seven T30 bolts from the PCV plate so you can replace the gaskets.
22) The front and rear gaskets look similar, but the front side one has a slight indent on the bottom side. They will fit perfectly into the slots in the intake, so be sure to mark which gasket is front and rear.
23) Install a new PCV plate and cap along with the gasket. The cap is purchased separately. The PCV plate will come with a new o-ring for the oil pipe.
24) Replace the four gaskets on the underside of the intake after cleaning the mating surface.
25) When installing the intake, make sure that the oil pipe is reconnected to the PCV plate. To do this, push the pipe as far forward as possible, then lay the intake into the engine, pushing it toward the back.
26) The injector wiring harness connectors get moved around a lot. Be sure that you have them secured out of the way so that they can be routed back for installation.
27) Work the oil pipe into position in front of the nipple of the PCV plate. Use a flat blade screw driver to push the pipe rearward so that the firewall end engages with the PCV plate, then work the clamp into place, so that the tab locks over the ridge of the plastic.
28) Install the ten alignment sleeves, then the ten nuts for the intake manifold. Torque it to 11 ft. lbs. from the inside out, alternating sides. After torquing the nuts, go back and retorque, just to be sure.
29) Install the injector harnesses. One of the connectors on mine turned a little so I lifted it back off and aligned it prior to pressing it into place. It takes just a little push to get it to lock in.
30) The remainder of installation is the reverse of the removal.
31) Upon first restart, turn the key to position two and let it sit there for a few seconds before trying to start it. Most, if not all, of the fuel dumped out of the fuel rail and the system needs to re-pressurize. It will run rough for a minute, then smooth out.
32) Drive and check for fuel leaks.

As a side note, this cleared my 1221 fault code that I thought was an O2 sensor. Cold starting is much quieter and it idles smoother.

[stargazer_61]

I'll try to link the pictures. Thanks!

[tncbass]

My friend, you are a life saver for posting this. Used your instructions plus the pics in this thread to replace the seals on my 94 540iA this week. Could not find any instructions anywhere else other than buyng the expensive Bentley manual (which I should do anyway). The extra connector near the throttle body you spoke of is for the ASC system secondary throttle body. It has a similar throttle position sensor installed. My car has ASC and I also removed this throttle body with the intake, still attached to the main throttle. I had several ounces of oil in my intake so I cleaned both throttles when I removed them to replace the main throttle body-to-intake gasket. The secondary throttle also has a cable attached which goes to the ASC actuator. This is removed in a similar manner to the main throttle cable. Having the secondary throttle installed makes getting the vacuum line for the brake booster a MAJOR A$* pain and mine was deteriorated from oil so I just cut the hose and replaced it. I also had to clean oil out of the plastic portion of the brake booster line.

I was able to get the retaining clips for the injector connectors off but I was not able to get them back on. Considering the injector harness assemblies themselves are held in place by 10mm nuts, I do not see the point of the retainers. It's not like the connectors are going to come off.

If you can't get your fuel lines off the rail, and you don't want to cut them, just disconnect the lines from the other ends at the body. Left side is near the fuse box and the right side is under the DME box. These were easy to get to and came off easily. This is also a good way to keep from spilling fuel all over the rear of your engine and bellhousing. I was able to get a small jar under the right side line and catch the fuel. Once the lines were loose I removed them from the clip at the back of the intake and the pulled them up above the intake so they would come out of the car easily with the intake. I still replaced the lines though, as they were rotten. I also replaced those ridiculous band clamps with regular flat tip type hose clamps.

Thanks again for the detailed instructions.