V6 Valve Cover Gasket Replacement
09-12-13, 05:12 AM
#1
Lexus Champion
Thread Starter
V6 Valve Cover Gasket Replacement
Introduction
Thanks to all the useful information found on Toyota Nation and Club Lexus, I was able to replace my V6 valve cover gaskets.
Here is a tutorial on how to replace the valve cover gaskets on the 1MZ-FE 3.0L V6 Engine. The procedure is the same as the V6 Toyota Solara, Camry, Avalon, Highlander, Sienna, Lexus ES300 and RX300.
The only difference for the ES300 is that it uses rear ignition coils instead of wires, and has a double throttle body instead of a single one on the VVT models.
Requirements
-Basic mechanical knowledge
-Hand tools, such as sockets, ratchets, torque wrenches, screwdrivers, etc.
-Repair manual for torque specs
-A strong back
-A friend for company
-Patience and a free weekend
Parts list
-Felpro valve cover gasket set with spark plug tube seals
-Intake plenum gasket
-PCV Valve and grommet
-Throttle Body and IACV gasket (optional)
-EGR valve and tube gaskets
-Spark plugs and wires (optional)
-Permatex RTV gasket maker
-2 Jugs of Toyota Long life coolant & distilled water
-Engine degreaser and brake cleaner
-New valve cover bolts and/or 5/16” washers
-Throttle body cleaner, toothbrush and rags
-Air filter (optional)
DIY Video
The video explains the valve cover gasket replacement procedure in detail. A brief pictorial follows.
EDIT: The photos from imageshack are now gone. Here's a link to the photos on a cloud drive. They're not labeled but are in order:
https://mega.nz/#F!qxxwBQxI!O_uyTkgS6IkpwDcWs4o7PA
Procedure
The 1MZ-FE 3.0L V6 engine. Have a good look at it before you start tear down.
Disconnect the battery.
Remove the engine cover, two torx bolts, depending on model.
Remove the strut tower brace if you have one.
Drain the engine coolant. Look down below the fans on the passenger side. There is a white plug that you turn counterclockwise to drain the coolant. Don’t turn it all the way out.
A better view of the radiator drain plug from underneath. Note the hole in the under-body cover to allow coolant to drain without removal.
Follow this thread to drain the engine coolant from the front and rear block drain ports:
https://www.clublexus.com/forums/es3...r-97-01-a.html
Remove the air box. There are two vacuum lines and an electrical connector for the MAF sensor that connect to it.
Remove the air resonator tube. Unscrew the tube clamp and remove the front valve cover ventilation hose.
Remove the throttle cables.
Remove the cable bracket (two 10mm bolts) and disconnect the spring.
Remove a few electrical connectors going to the throttle body and idle air control valve.
Disconnect the brake booster vacuum hose.
Remove two 12mm bolts and two 12 mm nuts on the throttle body. Note: it’s not necessary to remove the throttle body, as it can be removed with the plenum. However, it’s better to remove it for cleaning.
There are three lines going to the throttle body, the center one is a vacuum line, and the outer two are coolant hoses that must be removed.
Remove the throttle body.
Remove the plenum bracket nearest to the throttle body. Then remove two bolts holding the EGR valve onto the EGR tube.
Remove the EGR valve. Note the gaskets.
Remove the upper radiator hose.
Thanks to all the useful information found on Toyota Nation and Club Lexus, I was able to replace my V6 valve cover gaskets.
Here is a tutorial on how to replace the valve cover gaskets on the 1MZ-FE 3.0L V6 Engine. The procedure is the same as the V6 Toyota Solara, Camry, Avalon, Highlander, Sienna, Lexus ES300 and RX300.
The only difference for the ES300 is that it uses rear ignition coils instead of wires, and has a double throttle body instead of a single one on the VVT models.
Requirements
-Basic mechanical knowledge
-Hand tools, such as sockets, ratchets, torque wrenches, screwdrivers, etc.
-Repair manual for torque specs
-A strong back
-A friend for company
-Patience and a free weekend
Parts list
-Felpro valve cover gasket set with spark plug tube seals
-Intake plenum gasket
-PCV Valve and grommet
-Throttle Body and IACV gasket (optional)
-EGR valve and tube gaskets
-Spark plugs and wires (optional)
-Permatex RTV gasket maker
-2 Jugs of Toyota Long life coolant & distilled water
-Engine degreaser and brake cleaner
-New valve cover bolts and/or 5/16” washers
-Throttle body cleaner, toothbrush and rags
-Air filter (optional)
DIY Video
The video explains the valve cover gasket replacement procedure in detail. A brief pictorial follows.
EDIT: The photos from imageshack are now gone. Here's a link to the photos on a cloud drive. They're not labeled but are in order:
https://mega.nz/#F!qxxwBQxI!O_uyTkgS6IkpwDcWs4o7PA
Procedure
The 1MZ-FE 3.0L V6 engine. Have a good look at it before you start tear down.
Disconnect the battery.
Remove the engine cover, two torx bolts, depending on model.
Remove the strut tower brace if you have one.
Drain the engine coolant. Look down below the fans on the passenger side. There is a white plug that you turn counterclockwise to drain the coolant. Don’t turn it all the way out.
A better view of the radiator drain plug from underneath. Note the hole in the under-body cover to allow coolant to drain without removal.
Follow this thread to drain the engine coolant from the front and rear block drain ports:
https://www.clublexus.com/forums/es3...r-97-01-a.html
Remove the air box. There are two vacuum lines and an electrical connector for the MAF sensor that connect to it.
Remove the air resonator tube. Unscrew the tube clamp and remove the front valve cover ventilation hose.
Remove the throttle cables.
Remove the cable bracket (two 10mm bolts) and disconnect the spring.
Remove a few electrical connectors going to the throttle body and idle air control valve.
Disconnect the brake booster vacuum hose.
Remove two 12mm bolts and two 12 mm nuts on the throttle body. Note: it’s not necessary to remove the throttle body, as it can be removed with the plenum. However, it’s better to remove it for cleaning.
There are three lines going to the throttle body, the center one is a vacuum line, and the outer two are coolant hoses that must be removed.
Remove the throttle body.
Remove the plenum bracket nearest to the throttle body. Then remove two bolts holding the EGR valve onto the EGR tube.
Remove the EGR valve. Note the gaskets.
Remove the upper radiator hose.
Last edited by speedkar9; 02-15-16 at 07:33 PM.
09-12-13, 05:14 AM
#2
Lexus Champion
Thread Starter
Remove the ignition wires from the coils.
Remove all the electrical connectors going to the vacuum manifold. Label all connections for safety.
Remove the bolt and clips holding the spark plug wires and move them out of the way.
Remove two 10mm nuts to remove the vacuum manifold.
On the side of the plenum, there is a ground nut to remove, and a 14mm bolt holding it against the bracket at the firewall.
Use a socket to remove the 14 mm bolt.
Remove two 14mm nuts and two hex bolts holding the plenum on.
Remove the plenum. There’s a ground nut and the PCV hose behind the plenum to disconnect before freeing it from the vehicle.
Tape off the intake manifold so debris won’t fall into the engine.
Disconnect the rear fuel injectors and unbolt the two 10mm nuts holding it to the rear valve cover.
Reach down to the power steering pump and disconnect this wire. It will give you some wiggle room with the harness on top of the valve cover.
Remove two bolts holding the harness to the rear valve cover.
Remove this bracket near the dog-bone engine mount to give more room for the engine harness.
Follow the EGR tube down to the engine and remove the two 10 mm bolts. Do this by feel.
EGR tube removed.
Remove all the electrical connectors going to the vacuum manifold. Label all connections for safety.
Remove the bolt and clips holding the spark plug wires and move them out of the way.
Remove two 10mm nuts to remove the vacuum manifold.
On the side of the plenum, there is a ground nut to remove, and a 14mm bolt holding it against the bracket at the firewall.
Use a socket to remove the 14 mm bolt.
Remove two 14mm nuts and two hex bolts holding the plenum on.
Remove the plenum. There’s a ground nut and the PCV hose behind the plenum to disconnect before freeing it from the vehicle.
Tape off the intake manifold so debris won’t fall into the engine.
Disconnect the rear fuel injectors and unbolt the two 10mm nuts holding it to the rear valve cover.
Reach down to the power steering pump and disconnect this wire. It will give you some wiggle room with the harness on top of the valve cover.
Remove two bolts holding the harness to the rear valve cover.
Remove this bracket near the dog-bone engine mount to give more room for the engine harness.
Follow the EGR tube down to the engine and remove the two 10 mm bolts. Do this by feel.
EGR tube removed.
09-12-13, 05:15 AM
#3
Lexus Champion
Thread Starter
One more bolt on the valve cover holding the harness on.
And two more bolts on the transmission side of the engine.
Disconnect the connector going to the rear oxygen sensor. Be careful, I broke one of my wires.
Open heart surgery trying to patch the broken wire on the engine harness.
Lift up the engine harness away from the valve cover. Use rope to tie it to the wipers.
Pry up the valve cover and remove it.
This engine is in decent shape, just tarnished. It has only 257,000 km on it. No sludge.
Rear valve cover removed.
Replace the PCV valve and grommet.
Use a screwdriver and hammer to lift up the tab holding the spark plug tube seal. Pry out the seal.
Thoroughly clean up the valve cover with some degreaser.
Freeze the new spark plug tube seals overnight. Use a heat gun to heat up the valve cover and press in the new seal. A bit of grease works well as a lube. Use a large socket to tape the seal all the way down.
Bend the tabs back over the seals.
Use brake cleaner to clean up the gasket area on the valve cover and on the engine.
Install the new valve cover gasket.
Apply some Permatex gasket maker around the sharp corners where the valve cover gasket will sit, including around the cam bearing and where the surfaces aren’t flush.
And two more bolts on the transmission side of the engine.
Disconnect the connector going to the rear oxygen sensor. Be careful, I broke one of my wires.
Open heart surgery trying to patch the broken wire on the engine harness.
Lift up the engine harness away from the valve cover. Use rope to tie it to the wipers.
Pry up the valve cover and remove it.
This engine is in decent shape, just tarnished. It has only 257,000 km on it. No sludge.
Rear valve cover removed.
Replace the PCV valve and grommet.
Use a screwdriver and hammer to lift up the tab holding the spark plug tube seal. Pry out the seal.
Thoroughly clean up the valve cover with some degreaser.
Freeze the new spark plug tube seals overnight. Use a heat gun to heat up the valve cover and press in the new seal. A bit of grease works well as a lube. Use a large socket to tape the seal all the way down.
Bend the tabs back over the seals.
Use brake cleaner to clean up the gasket area on the valve cover and on the engine.
Install the new valve cover gasket.
Apply some Permatex gasket maker around the sharp corners where the valve cover gasket will sit, including around the cam bearing and where the surfaces aren’t flush.
09-12-13, 05:16 AM
#4
Lexus Champion
Thread Starter
Reinstall the rear valve cover. Make sure the spark plug tube seals seat properly.
One of the flaws of the 1MZ-FE engine were these valve cover bolts. They are only thread a certain distance, and often bottom out before the specified torque is reached, causing a leak. Additionally, they are equipped with crushed washers, once compressed, cannot be properly torqued again. Add two 5/16” washers to the bolt to prevent more leaks from under-torquing.
Install eight valve cover bolts. Torque spec is 59 in – lb.
Front Valve Cover
Remove the ignition coils.
Remove the front valve cover ventilation hose that goes to the air intake.
Remove eight 10mm bolts holding the valve cover on and pry it off.
A look under the front valve cover.
Clean up the valve cover and install the new gaskets and seals.
Reinstall the front valve cover, remembering to put two 5/16” washers on the bolts to take up the slack of the crushed washers.
Torque the bolts down to 59 in –lb.
Reinstall the ignition coils. Good time to change spark plugs.
Both valve covers replaced. Begin reassembly.
There are five bolts that hold the engine harness on the rear valve cover.
Reinstall the bolt holding the power steering line to the plenum bracket. Tighten up the plenum bracket bolt at the bottom of the engine if it was loosened.
Reinstall the spark plug wires. Good time to change these out too.
Reconnect the oxygen sensor, power steering pump sensor and this connector on the transmission side of the engine.
Reconnect the rear fuel injectors and tighten down the wiring harness on the rear valve cover.
Use some throttle body cleaner to clean up the intake plenum. The EGR port was especially clogged.
Reinstall the EGR tube. Don’t forget the gasket.
One of the flaws of the 1MZ-FE engine were these valve cover bolts. They are only thread a certain distance, and often bottom out before the specified torque is reached, causing a leak. Additionally, they are equipped with crushed washers, once compressed, cannot be properly torqued again. Add two 5/16” washers to the bolt to prevent more leaks from under-torquing.
Install eight valve cover bolts. Torque spec is 59 in – lb.
Front Valve Cover
Remove the ignition coils.
Remove the front valve cover ventilation hose that goes to the air intake.
Remove eight 10mm bolts holding the valve cover on and pry it off.
A look under the front valve cover.
Clean up the valve cover and install the new gaskets and seals.
Reinstall the front valve cover, remembering to put two 5/16” washers on the bolts to take up the slack of the crushed washers.
Torque the bolts down to 59 in –lb.
Reinstall the ignition coils. Good time to change spark plugs.
Both valve covers replaced. Begin reassembly.
There are five bolts that hold the engine harness on the rear valve cover.
Reinstall the bolt holding the power steering line to the plenum bracket. Tighten up the plenum bracket bolt at the bottom of the engine if it was loosened.
Reinstall the spark plug wires. Good time to change these out too.
Reconnect the oxygen sensor, power steering pump sensor and this connector on the transmission side of the engine.
Reconnect the rear fuel injectors and tighten down the wiring harness on the rear valve cover.
Use some throttle body cleaner to clean up the intake plenum. The EGR port was especially clogged.
Reinstall the EGR tube. Don’t forget the gasket.
09-12-13, 05:17 AM
#5
Lexus Champion
Thread Starter
Install a new plenum gasket.
Reinstall the intake plenum. Connect the ground wire at the back and PCV hose before tightening down.
Tighten down the intake plenum. Two nuts, 2 hex bolts.
Then tighten up the 14 and 12 mm bolts on the back brackets near the firewall.
Reinstall the vacuum manifold.
Reconnect the electrical connections.
One more ground bolt on the side of the plenum.
Reinstall this bracket near the dog bone engine mount. Three 12mm bolts.
Reinstall the upper radiator hose.
Reconnect the brake booster vacuum line.
Make sure the clamp is on properly. You don’t want to lose vacuum suddenly in your brakes.
Use some throttle body cleaner and your brother’s toothbrush to clean up the throttle body on both sides. Open up the 4 Philips screws (if you can!) and clean up the idle air control valve.
Reinstall the EGR valve. Don’t forget the gaskets. Snug tight the 10mm nuts, otherwise you’ll hear an exhaust leak.
Replace the throttle body gasket with a new one.
Replace the throttle cables.
Replace a few electrical connections going to the throttle body, IACV and EGR.
Reinstall the intake plenum. Connect the ground wire at the back and PCV hose before tightening down.
Tighten down the intake plenum. Two nuts, 2 hex bolts.
Then tighten up the 14 and 12 mm bolts on the back brackets near the firewall.
Reinstall the vacuum manifold.
Reconnect the electrical connections.
One more ground bolt on the side of the plenum.
Reinstall this bracket near the dog bone engine mount. Three 12mm bolts.
Reinstall the upper radiator hose.
Reconnect the brake booster vacuum line.
Make sure the clamp is on properly. You don’t want to lose vacuum suddenly in your brakes.
Use some throttle body cleaner and your brother’s toothbrush to clean up the throttle body on both sides. Open up the 4 Philips screws (if you can!) and clean up the idle air control valve.
Reinstall the EGR valve. Don’t forget the gaskets. Snug tight the 10mm nuts, otherwise you’ll hear an exhaust leak.
Replace the throttle body gasket with a new one.
Replace the throttle cables.
Replace a few electrical connections going to the throttle body, IACV and EGR.
09-12-13, 05:18 AM
#6
Lexus Champion
Thread Starter
Replace the air resonator hose and the ventilation hose from the front valve cover.
Replace the airbox and two vacuum lines. Connect the MAF sensor.
Refill the engine coolant with a 50/50 mixture of Toyota Long Life Coolant (Red) and distilled water.
Premixing coolant in a jug makes for a big mess.
Turn on the car and let it run for 10-15 mins, with the radiator cap loose and HVAC set to HOT. This will allow air bubbles to escape and fluid to properly circulate through the system.
Double check the coolant levels and refill as necessary.
Make sure the temperature is within the normal range and go for a test drive.
Recommendations
Go for a test drive and listen for any unusual noises. I had a louder than usual exhaust note that turned out to be loose EGR tube nuts.
Degrease and wash the engine bay completely. This will remove spilled coolant residue and oil buildup from that leaky valve cover. Scrub the leaky valve cover area clean. New or other leaks will be easier sought.
Cleaning the IACV and throttle body will help a lot with the idle performance. I couldn’t get the IACV screws open, but my car now runs notably smoother with a clean throttle body, EGR port and intake plenum.
There are many other recommended services to perform when the intake plenum is off, such as replacing the coolant by-pass hose under the intake manifold, the rear oxygen sensor, spark plugs and wires, maybe the rear engine mount, knock sensors, cam/crank seals, valve adjustments, etc.
Conclusions
Replacing the valve cover gaskets on a V6 Camry isn’t difficult for the handy DIY’er. No special tools are required. However, it is time consuming and physically demanding, as you are required to bend over a lot to access the rear of the engine.
Make sure you use a torque wrench on the valve covers, and take your time and label vacuum hoses and electrical connectors.
Once again, thanks to all on this board and on TN for a learning experience, and I hope I help someone with this DIY. If there are any recommendations I need to add, I am willing to update this post.
Replace the airbox and two vacuum lines. Connect the MAF sensor.
Refill the engine coolant with a 50/50 mixture of Toyota Long Life Coolant (Red) and distilled water.
Premixing coolant in a jug makes for a big mess.
Turn on the car and let it run for 10-15 mins, with the radiator cap loose and HVAC set to HOT. This will allow air bubbles to escape and fluid to properly circulate through the system.
Double check the coolant levels and refill as necessary.
Make sure the temperature is within the normal range and go for a test drive.
Recommendations
Go for a test drive and listen for any unusual noises. I had a louder than usual exhaust note that turned out to be loose EGR tube nuts.
Degrease and wash the engine bay completely. This will remove spilled coolant residue and oil buildup from that leaky valve cover. Scrub the leaky valve cover area clean. New or other leaks will be easier sought.
Cleaning the IACV and throttle body will help a lot with the idle performance. I couldn’t get the IACV screws open, but my car now runs notably smoother with a clean throttle body, EGR port and intake plenum.
There are many other recommended services to perform when the intake plenum is off, such as replacing the coolant by-pass hose under the intake manifold, the rear oxygen sensor, spark plugs and wires, maybe the rear engine mount, knock sensors, cam/crank seals, valve adjustments, etc.
Conclusions
Replacing the valve cover gaskets on a V6 Camry isn’t difficult for the handy DIY’er. No special tools are required. However, it is time consuming and physically demanding, as you are required to bend over a lot to access the rear of the engine.
Make sure you use a torque wrench on the valve covers, and take your time and label vacuum hoses and electrical connectors.
Once again, thanks to all on this board and on TN for a learning experience, and I hope I help someone with this DIY. If there are any recommendations I need to add, I am willing to update this post.
The following users liked this post:
99RX300PDX (06-29-18)
09-12-13, 10:42 AM
#7
Good job, but that's a lot more steps than i remember it being...
Engine cover, front cover was cake, take off the coil packs, then boom, access to it there.
Rear, It was airbox completely out, top half of intake manifold [like you did], but left the TB on it, no point in removing it. All vacuum & electrical unclipped, and that harness running down the middle pops out then you have access to the back as-is. About 2 hrs of labor all in all with hand tools.
Engine cover, front cover was cake, take off the coil packs, then boom, access to it there.
Rear, It was airbox completely out, top half of intake manifold [like you did], but left the TB on it, no point in removing it. All vacuum & electrical unclipped, and that harness running down the middle pops out then you have access to the back as-is. About 2 hrs of labor all in all with hand tools.
The following users liked this post:
99RX300PDX (06-29-18)
Trending Topics
09-12-13, 12:14 PM
#9
Awesome job for putting this together in pictures AND video. I think a lot of people will benefit from your work.
I recommend specifying the size the hex bolts on the intake plenum and the Torx bit for the wiring harness on the front valve cover. I bet it will come up in the future.
I recommend specifying the size the hex bolts on the intake plenum and the Torx bit for the wiring harness on the front valve cover. I bet it will come up in the future.
09-12-13, 07:34 PM
#11
Lexus Champion
Thread Starter
It was my first valve cover job, so I took my time and labeled everything, and took pictures and shot the video along the way. If I had to do it again, I'd average 5 hours for a proper, unrushed job.
Awesome job for putting this together in pictures AND video. I think a lot of people will benefit from your work.
I recommend specifying the size the hex bolts on the intake plenum and the Torx bit for the wiring harness on the front valve cover. I bet it will come up in the future.
I recommend specifying the size the hex bolts on the intake plenum and the Torx bit for the wiring harness on the front valve cover. I bet it will come up in the future.
The harness on the front cover is held in by the two torx screws holding on the plastic engine cover on the Solara. Presumably, the harness is held in by the Torx E6 studs on the ES300, as the cover design is slightly different.
I'm not sure where the knock sensors are located. Anyone else chime in?
09-12-13, 07:35 PM
#12
As always, a very detailed and well written DIY from Speedkar9. I definitely will benefit from this in the future and can only imagine others will be helped as well. Thanks for all the hard work in putting this together, I can only imagine its a bit of a pain to stop what you're doing to take pictures/video.
09-12-13, 10:12 PM
#13
Wow, this is a great write-up! I bet tons of people on here will benefit from this because sooner or later it seems these always start leaking. And it looks like you guys with these newer engines have a much easier time getting the rear wiring harness out of the way, wish it was that easy on the old cars 