DIY Coolant Valley Leak Repair

[ASUMTNEER]

Ahh gotcha. I used a short socket on an extension to back that bolt out and then used a magnet on a stick to grab it and retrieve it. If you’re using a socket and don’t have a magnet, I’ve used something like electrical or painters tape over the open end of the socket and then press the socket onto the bolt and that extra tape taking up some room inside the sockets lets it have a friction fit that grabs and holds the bolt head.

If your socket is running into the fuel line as you back out that bolt the last few turns, then you could use a Phillips screwdriver to back it out those last few turns, I believe my bolts had a Phillips head relief cut into them. Then a magnet, sticky tape or needle nose pliers to help grab the bolt head and retrieve it.

Good thought. I'll grab a magnet today and I'm borrowing a 1/4" ratchet, socket and extension from work to make sure the bolt is backed out all the way. The problem with the 3/8" extension is that it rubs between the manifold and the hard coolant line and feels like there's pressure every turn, so you don't know if the bolt is completely backed out or not. I'll report back tonight with my progress. FWIW, the bolt heads have some sort of star shape cut into them. I'll find the size and post it tonight for reference.

 

[ASUMTNEER]

Ahh gotcha. I used a short socket on an extension to back that bolt out and then used a magnet on a stick to grab it and retrieve it. If you’re using a socket and don’t have a magnet, I’ve used something like electrical or painters tape over the open end of the socket and then press the socket onto the bolt and that extra tape taking up some room inside the sockets lets it have a friction fit that grabs and holds the bolt head.

If your socket is running into the fuel line as you back out that bolt the last few turns, then you could use a Phillips screwdriver to back it out those last few turns, I believe my bolts had a Phillips head relief cut into them. Then a magnet, sticky tape or needle nose pliers to help grab the bolt head and retrieve it.

just to be clear...that fuel hose and bracket with the 10mm bolt isn't attached to the black plastic wire loom cover, right?

 

[jmanscotch]

just to be clear...that fuel hose and bracket with the 10mm bolt isn't attached to the black plastic wire loom cover, right?

If I recall, the 10MM bolt goes through the wiring harness hard plastic and then through a bracket for the fuel crossover pipe, so yeah, it holds both on and needs removed otherwise the wire loom will remain attached to the intake manifold.

 

[ASUMTNEER]

OK, quick update with some notes:

A 1/4" drive shallow 12mm socket with a 6" extension is the ticket for that back passenger side manifold bolt. I think it was hanging on by one thread the day before, when I was working with the 3/8" drive tools, and holding the manifold on. As soon as I backed that bolt off another turn, I was able to lift the manifold off easily. I'm still a little concerned about how I'm going to get that bolt back into place when the manifold is seated back down.

I disconnected the fuel crossover line on both sides of the manifold and didn't lose any gas. I believe that when I broke the seal loose on the manifold (before I disconnected the fuel line), it released pressure so I wasn't sprayed with fuel when I disconnected those lines. This would be my suggested method for anyone doing this job. I could barely even feel the head of that bolt on the rear of the manifold with my finger, there was no way I was getting a tool to it and turning it. That bolt does not go through the wire harness, so the line will come right off with the manifold when you lift it. This way you will only have to disconnect the drivers side wire harness clip (easy to do) and break the passenger side clip (a little nerve racking because of all of the cracking noises when you do it).

Also, I drained the radiator and the block on the passenger side and it drained enough coolant so that when I lifted the valley plate off the head coolant didn't run out everywhere. I don't think I'd mess with doing the drivers side as I couldn't figure out how to get access to drain it.

I got the valley plate sealed and placed back on the set overnight. I think the coolant transfer tube slid on appropriately, but I'll fond out for sure tonight when I refill it with coolant. Keeping my fingers crossed on that one!

 

[jmanscotch]

Good notes and nicely done!

 

[r2m]

OK, quick update with some notes:

A 1/4" drive shallow 12mm socket with a 6" extension is the ticket for that back passenger side manifold bolt. I think it was hanging on by one thread the day before, when I was working with the 3/8" drive tools, and holding the manifold on. As soon as I backed that bolt off another turn, I was able to lift the manifold off easily. I'm still a little concerned about how I'm going to get that bolt back into place when the manifold is seated back down.

I disconnected the fuel crossover line on both sides of the manifold and didn't lose any gas. I believe that when I broke the seal loose on the manifold (before I disconnected the fuel line), it released pressure so I wasn't sprayed with fuel when I disconnected those lines. This would be my suggested method for anyone doing this job. I could barely even feel the head of that bolt on the rear of the manifold with my finger, there was no way I was getting a tool to it and turning it. That bolt does not go through the wire harness, so the line will come right off with the manifold when you lift it. This way you will only have to disconnect the drivers side wire harness clip (easy to do) and break the passenger side clip (a little nerve racking because of all of the cracking noises when you do it).

Also, I drained the radiator and the block on the passenger side and it drained enough coolant so that when I lifted the valley plate off the head coolant didn't run out everywhere. I don't think I'd mess with doing the drivers side as I couldn't figure out how to get access to drain it.

I got the valley plate sealed and placed back on the set overnight. I think the coolant transfer tube slid on appropriately, but I'll fond out for sure tonight when I refill it with coolant. Keeping my fingers crossed on that one!

View attachment 3446909

View attachment 3446910

View attachment 3446911

Awesome job! Heck, you can hire yourself out for $75.00 - $125.00/hr and quite your day job!!

 

[ASUMTNEER]

I got it all put back together last night, filled the system with coolant, and fired her up! Everything is good. No leaks, no lights on the dash. It's idling a little high at start up, but I'm hoping that settles back down. I cleaned the throttle body and EGR system while it was out of the car, so maybe the car is adjusting to this?
Huge thanks to all of you on this forum that have contributed to this thread. There is no way I would have tied this job without all of the info here, and info linked here. To all of those considering doing this job on your own, I encourage you to attempt it. This is the biggest job I've ever done, granted I've ben working on my own stuff for 20 years now, this is the most involved job by far. I probably had 8'ish hours in it from beginning to completion. I probably read through this DIY 30 times, no joke, getting up the courage to tackle this.
@jmanscotch thank you for everything and kudos to you for hanging around this forum to help out folks like me. I will be doing the same.

 

[jmanscotch]

Well done and cheers bud!

 

[r2m]

I got it all put back together last night, filled the system with coolant, and fired her up! Everything is good. No leaks, no lights on the dash. It's idling a little high at start up, but I'm hoping that settles back down. I cleaned the throttle body and EGR system while it was out of the car, so maybe the car is adjusting to this?
Huge thanks to all of you on this forum that have contributed to this thread. There is no way I would have tied this job without all of the info here, and info linked here. To all of those considering doing this job on your own, I encourage you to attempt it. This is the biggest job I've ever done, granted I've ben working on my own stuff for 20 years now, this is the most involved job by far. I probably had 8'ish hours in it from beginning to completion. I probably read through this DIY 30 times, no joke, getting up the courage to tackle this.
@jmanscotch thank you for everything and kudos to you for hanging around this forum to help out folks like me. I will be doing the same.

Eight hours is not that long for such an undertaking!
Newly married, it seemed forever when I did a valve job on my old BMW. We were in an apartment with only a carport (no garage) I had to put all the parts and tools away along with cleaning up every time I was done after the couple hours I had after my day job to work on it.

 

[crolison]

acquired all the gaskets, fipg, coolant to diy the valley plate leak on my wife’s gx460.

Started today with focusing on the connectors, bolts on the backside of the intake manifold. The passenger side connector was so brittle and just came apart, the fuel line bolt and drivers side connector took about 45 minutes to undo.

Stopped there for the day, as snow is coming saturday and wanted a couple days to knock it out in good weather. So pushed back till late next week. When started up to check on things I noticed a whine coming from the front of the engine. So May go ahead and throw on a new water pump, tensioner, idler, and belt.

 

[ASUMTNEER]

acquired all the gaskets, fipg, coolant to diy the valley plate leak on my wife’s gx460.

Started today with focusing on the connectors, bolts on the backside of the intake manifold. The passenger side connector was so brittle and just came apart, the fuel line bolt and drivers side connector took about 45 minutes to undo.

Stopped there for the day, as snow is coming saturday and wanted a couple days to knock it out in good weather. So pushed back till late next week. When started up to check on things I noticed a whine coming from the front of the engine. So May go ahead and throw on a new water pump, tensioner, idler, and belt.

Did you finish?

 

[jeremy j]

Really appreciate this thread. Looks like I'll be doing this repair soon.

I've had the GX almost a year and 6 months ago I noticed it was low on coolant and topped it off. I've been monitoring it since then and it losing maybe a 1/2 pint per month from the overflow. I had been looking for leaks and never could find anything but I could smell coolant sometimes. I just kept an eye on it and made sure it was ok.

Well today, I crawled under it and found this mess:

 

[crolison]

Did you finish?

started today:
- got the intake ready to pull
- down to the water pump
- changed the tensioner and idler
- pulled the fan pulley bracket

Wasn’t planning on pulling the tan pulley bracket, but spun it and it’s also a culprit in the pulley noise. The tensioner has been changed before and the bearing on that is bad too. Luckily oreilly has an aisin one locally that is only $50 more than rock auto.

Tomorrow I have a couple of hours to work, so planning:

Focus on water pump as it will also drain the block then I pull it. Then if I have time pull the intake.

Tuesday I have all day so should be able finish up. Then Wednesday will be bleed the coolant system.

 

[crolison]

In about three hours for the water pump installed, and the valley plate pulled and cleaned up.

Heading to the auto part store for a new tan bracket, and then kids dentist appointment.

After the appointment I’m planning on getting the valley plate installed and torqued down so the gasket maker has time to setup over night.

Then tomorrow will be finalizing it.

 

[crolison]

Further work today, have the serpentine belt system all installed with the new fan bracket.

Valley plate is installed, pcv and egr are buttoned up.

 

[crolison]

All done, approximately 8.5ish hours to do:
- reseal valley plate
- belt tensioner
- idler
- water pump
- new belt
- fan pulley bracket

 

[r2m]

Did you have to use any unique tools out of the ordinary metric socket set, hammer, various screwdrivers, maybe allen wrenches?
Did you need to torque the manifold back on? If so, what were the numbers?

 

[ASUMTNEER]

no special tools needed. Torque specs for both the manifold and the valley plate are 15ft lbs

 

[jeremy j]

Working on this today and sure wish I had read the entire thread before starting. I ended up doing the same as @ASUMTNEER did and disconnected the fuel rails so I didn't have to do the 10mm bolt on the back of the intake manifold. I have big hands and even after removing the heater lines above it, I still couldn't feel the 10mm. Disconnecting the fuel lines was very easy. I removed the drivers side clip by using an open end wrench on the bolt and slowly backed it out and then intentionally broke the passenger side clip.

While doing this, I made a big mistake. I thought I could slightly move the intake manifold a little and maybe get to the bolt but forgot to disconnect the throttle body connector.

I ordered this part from partsgeek and I think it is the right one. We'll see. At least it is something that I can do after I finish the rest of the work. Hopefully I can find the wiring diagram with colors for it. If not, I'll be begging @Acrad for some help.

14 2014 Lexus GX460 Electronic Throttle Body Actuator Connector - Fuel Injection - Standard Motor Products - PartsGeek

Buy a 2014 Lexus GX460 Electronic Throttle Body Actuator Connector at discount prices. Choose top quality brands Standard Motor Products.

www.partsgeek.com

After getting the intake manifold, it's pretty clear mine has been leaking for a while. Lots of crusty stuff around the EGR cooler.

Cleaning things up so I can get the FIPG back on before shutting down for the evening.

 

[jeremy j]

Got everything all buttoned back up and should be getting a new plug and pigtail for my throttle body today. Digging through the service manual, I found these diagrams and the connector looks the same and the colors match the wires I have. As you see in the pic above, I also have the black and white wires still connected and they match up to this so should be pretty easy to repair.