Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak)
- Thread starter cc93cruiser
- Start date
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TLC2013
SILVER Star
kms254
SILVER Star
Pretty much wrapped it up today.
I tested the coolant system for pressure. It had 15psi for 30 minutes!
After that I started to reassemble. Note: the crank case oil seperator should probably go in before the SAIS valves. I had to wiggle and undo those bolts a few times before I could get the back bolt in for the crank case oil separator!
The diagram I saw said the two gaskets between the tubes and SAIS valves were non reusable. They probably are but I replaced them for the grand total of 7 bucks..
Mostly assembled now. I’ll probably leave it like this and do plugs while it’s apart…
I bought a top side creeper and it worked quite well.
I tested the coolant system for pressure. It had 15psi for 30 minutes!
After that I started to reassemble. Note: the crank case oil seperator should probably go in before the SAIS valves. I had to wiggle and undo those bolts a few times before I could get the back bolt in for the crank case oil separator!
The diagram I saw said the two gaskets between the tubes and SAIS valves were non reusable. They probably are but I replaced them for the grand total of 7 bucks..
Mostly assembled now. I’ll probably leave it like this and do plugs while it’s apart…
I bought a top side creeper and it worked quite well.
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kms254
SILVER Star
Engine buttoned up last night, started up first try and no codes or leaks! . Burped the coolant system with just over 3 gallons of coolant.
- Thread starter
- #125
Glad to see everyone using this thread as a small resource. A lot of knowledgeable members contributed to this thread. Honestly this is a repair that seems like it happens way to frequently with the 3urfe in the 200 series (if you own a 200 and haven't dealt with this yet, consider yourself lucky..lol). Maybe @Romer can sticky this thread in the 200 series FAQ in Repairs /Maintenance-Engine?
kms254
SILVER Star
I figured rather than making another post I just dumped what I learned in here for that reason.
TLC2013
SILVER Star
This is a great thread and resource. Nice work @kms254. Wish I had the time and a patient better half to allow me tackle this my self lol. Appreciate you documenting your process/progress.
I have a small leak at the valley plate and will be having my Indy Mechanic take care of this in a Couple weeks. What I find interesting is that both a Lexus dealership and a Toyota dealership claimed there isn’t a stated hourly rate for this job. Lexus wanted 12 hours and after talking with their service manager he said he would come down to 8 and give me a deal. Toyota claimed 6-7 hours shop time ($1,200 labor) and said their rate is based on what they charge for removing the intake manifold plus a couple extra hours of shop time for the valley leak repair.
I have a small leak at the valley plate and will be having my Indy Mechanic take care of this in a Couple weeks. What I find interesting is that both a Lexus dealership and a Toyota dealership claimed there isn’t a stated hourly rate for this job. Lexus wanted 12 hours and after talking with their service manager he said he would come down to 8 and give me a deal. Toyota claimed 6-7 hours shop time ($1,200 labor) and said their rate is based on what they charge for removing the intake manifold plus a couple extra hours of shop time for the valley leak repair.
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Done
- Thread starter
- #129
If my arm wasn't messed up, I'd tell you to swing by.. If you decide to tackle it yourself, I still have the Toyota Black Sealant left over-In Hayward.
kms254
SILVER Star
Well if I saved 1200 bucks, I guess I can justify the full set of bud built skids I just bought…
Really, I could do this job in half the time the second time. For a professional mechanic who knows what they are doing with all the parts and tools there 6 hours seems reasonable.
Things I wasted time on in no particular order:
- Trips to the store for more coolant, pressure tester, paper towels. Waiting on amazon for a new torque wrench, the top side creeper, fluid transfer pump, the SAIS exhaust gaskets, magnetic pickup tool..
- Trying to pull the crank case oil separator out before the SIAS valves
- Installing the SAIS valves before installing the crank case oil separator
- Undoing the front of the SAIS tubes
- Dropping a 3/8 stubby extension with Torx driver behind the back passenger side of block doing the LAST intake manifold bolt(2 hours retrieving)
- Hand cleaning every single bolt, hand checking the fitment of each bolt before installation
- Cleaning the valley plate
- Continuity cleaning the valley area whenever anything landed in it..
- Removing any sign of pink reside from all parts so if the leak ever shows up I will know it is new
- Taking off all the skid plates
- Angling the truck from side to side while draining the block to get out every last drop(not really needed)
The top side creeper was super helpful and if any one in the Denver/Boulder/Fort Collins area wants to use it I'm sure we can work something out.
TLC2013
SILVER Star
Right on, appreciate the offer @cc93cruiser. Hope that arm feels better. Good to hear from a fellow Bay Area cruiser enthusiast.
Been following these posts and purchased all the parts (o rings, sealant and gaskets), just waiting on delivery.
does anyone know the bolt part number for the intake mainfold?
I see one bolt missing on the large black plastic cover which is the intake mainfold cover.
I see one bolt missing on the large black plastic cover which is the intake mainfold cover.
Well, I was losing coolant from the reservoir so I scoped it as best I could. Found this:
Untitled by Jeff Nada, on Flickr
So, I started pulling it apart and the culprit was easily visible:
Untitled by Jeff Nada, on Flickr
Untitled by Jeff Nada, on Flickr
So, I fixed it using all the tips and tricks depicted here. Burped it and thought I was good....
Untitled by Jeff Nada, on FlickrSo, I started pulling it apart and the culprit was easily visible:
Untitled by Jeff Nada, on FlickrUntitled by Jeff Nada, on FlickrSo, I fixed it using all the tips and tricks depicted here. Burped it and thought I was good....
Noticed the coolant level in the reservoir was coming down like 3/8 of an inch from full... Chalked it up to additional air in the system. Took it for a 60 min drive today and noticed it was down another 3/8 of an inch again. Borrowed a pressure tester and found the following:
Initial pressurization:
Untitled by Jeff Nada, on Flickr
At 15 min past:
Untitled by Jeff Nada, on Flickr
At 30 min:
Untitled by Jeff Nada, on Flickr
At 45 min:
Untitled by Jeff Nada, on Flickr
At 1 hr:
Untitled by Jeff Nada, on Flickr
So, do I need to pull this whole thing back apart??? I was meticulous about my assembly so I hope it's not the coolant valley plate. Even worse, I hope it's not a head gasket! Any and all advice is appreciated!
Initial pressurization:
Untitled by Jeff Nada, on FlickrAt 15 min past:
Untitled by Jeff Nada, on FlickrAt 30 min:
Untitled by Jeff Nada, on FlickrAt 45 min:
Untitled by Jeff Nada, on FlickrAt 1 hr:
Untitled by Jeff Nada, on FlickrSo, do I need to pull this whole thing back apart??? I was meticulous about my assembly so I hope it's not the coolant valley plate. Even worse, I hope it's not a head gasket! Any and all advice is appreciated!
I had to refill mine for 3-4 heat/cool cycles before it stayed steady. The coolant system pressure decay is concerning though. You used the recommended Toyota sealant and two new orings? Lubed the orings with coolant? Torqued the valley plate bolts to 15 ft lbs?
Thanks @Supra88 - I used the Aisin sealant that some others have used successfully. I doubt that's the issue as it would take a while for it to fail if that's the issue (Aisin FIPG Formed-In-Place-Gasket AB1207B1 - https://www.yotashop.com/aisin-fipg-formed-in-place-gasket-ab1207b1/). It's rated for the pink coolant and I applied based on the instructions (within 3 min of application, torqued at 10 min post application)
I did use two new o-rings and lubed them with coolant, use a new gasket for the check valves and even new gaskets for the coolant bypass in the front.
I did use two new o-rings and lubed them with coolant, use a new gasket for the check valves and even new gaskets for the coolant bypass in the front.
You did everything correctly. The decay isn't linear and that makes me think that it's not your sealant and more likely a hose. It appears that 13 psi is the threshold where it's allowing air or coolant to slowly escape. You'd think you'd see coolant though.
My suggestion before pulling things apart:
1. Top off the coolant for a couple more heat/cool cycles.
2. Pressurize the system to 17-18 pounds to amplify the problem. Check all hoses, particularly the ones you removed for the job, thoroughly.
3. Use a borescope to look under the intake manifold.
4. Check heater tees/hoses. My tees crumbled and showed signs of leaking.
Well, I checked things out but didn't get too invasive... Pulled the throttle body off so I could get a borescope down the passenger side under the runners. It all looked as clean and dry as when I put it back together. Did as @Supra88 suggested and pressurized to ~17lbs and looked the entire engine over carefully from top to bottom. No sign of leaks found.
Given this, I'm going to top it off, heat cycle it for a few days and see where things settle (or if they do). If I keep consuming coolant, I'm going to do a head gasket test and, if that's negative, I will put dye in the coolant and get the UV light out to see if I can track it down.
If anyone has better ideas, I'm wide open to them! Thanks all!
Given this, I'm going to top it off, heat cycle it for a few days and see where things settle (or if they do). If I keep consuming coolant, I'm going to do a head gasket test and, if that's negative, I will put dye in the coolant and get the UV light out to see if I can track it down.
If anyone has better ideas, I'm wide open to them! Thanks all!
Is it possible that your tester has a slight leak? Did the 17 psi show any decay?
My 100 series had a slow decay and it ended up being coolant leaking into the transmission warm up circuit in the radiator. I doubt that's your issue. Would be surprised it's a head gasket too.
I think topping it off 2-3 more heat cycles is a good plan. I was really surprised how long it took mine to finally stabilize after doing the coolant valley fix.
My 100 series had a slow decay and it ended up being coolant leaking into the transmission warm up circuit in the radiator. I doubt that's your issue. Would be surprised it's a head gasket too.
I think topping it off 2-3 more heat cycles is a good plan. I was really surprised how long it took mine to finally stabilize after doing the coolant valley fix.