Front Water Bypass (solved with write up)

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Saw a couple drops of coolant on the ground this morning, thought it was power steering leak, but the compressor had drops accumulated on it's bottom. Traced it, something is dripping onto the compressor, but what looks like from the throttle body/on top of the manifold at some gasket? I've never familiarized myself with this part of the engine cause I've never had to do a starter/intake work. It doesn't look simple unfortunately. The first picture is zoomed out to show where I am. The others are different angles of where coolant has landed... not as important.

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After taking initial pictures, I like to clean area really good. Then watch daily for leak source to reappear, so I can pinpoint.

It's hard to tell with your pictures, if coolant hoses, front water by-pass or both are leaking.

See The Redbaron post #45 then again at #58, for front water by-pass leak on a VVt-i engine. With VVT-i it's necessary to remove intake manifold, this may not be the case with non VVT-i like yours.
 
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After taking initial pictures, I like to clean area really good. Then watch daily for leak source to reappear, so I can pinpoint.

It's hard to tell with your pictures, if coolant hoses, front water by-pass or both are leaking.

See The Redbon post #45 then again at #58, for front water by-pass leak on a VVt-i engine. With VVT-i it's necessary to remove intake manifold, this may not be the case with non VVT-i like yours.
And thank you, ahead of time:)
 
Yes, but don't spend too much time there with tip of power washer. Water will run into valley of engine and flow out drain ports at back under starter. If any old mice nest under there, it plugs the drains somewhat and may flood the starter. The Denso starter is sealed, but seals get old and shrink/leak. Also don't hit hoses & wires with tip of HP washer to close, it will cut them.

Rear & front water bypass joint.jpg
01 Engine valley drain holes.jpg

You'll be blow water right where intake gasket meets the head. So don't stay too long or water may get into heads intake post. This is more of issue with VVT-1.
Coolant leak detection cleaning (9).JPG

After clean (power washer, degreasing & scrubbing with tooth brush). Then watch after running engine and or driving over next few days. Look each time you stop.
Coolant Water by-pass joint, front PS front nut with pointer.JPG

This is on VVt-i engine which have the AI pump stuff in valley along with starter. Non VVT-i just have the starter.
052.JPG


Keep water away from drive belt, idler & tensioner pulley bearings. I just remove those when doing a really heavy power washing. Reason is water can enter seal of bearing and they then go bad faster or faster.

I like to washer while on a slight hill (front higher than rear) so water flow to rear.

Again; Run engine and go for a drive as soon as done. This with dry water that may have gotten into head ports, valley, spark plugs tubes or wherever.

You're more than welcome!
 
Yes, but don't spend too much time there with tip of power washer. Water will run into valley of engine and flow out drain ports at back under starter. If any old mice nest under there, it plugs the drains somewhat and may flood the starter. The Denso starter is sealed, but seals get old and shrink/leak. Also don't hit hoses & wires with tip of HP washer to close, it will cut them.

View attachment 1585911 View attachment 1585915
You'll be blow water right where intake gasket meets the head. So don't stay too long or water may get into heads intake post. This is more of issue with VVT-1.
View attachment 1585913
After clean (power washer, degreasing & scrubbing with tooth brush). Then watch after running engine and or driving over next few days. Look each time you stop.
View attachment 1585912
This is on VVt-i engine which have the AI pump stuff in valley along with starter. Non VVT-i just have the starter.
View attachment 1585914

Keep water away from drive belt, idler & tensioner pulley bearings. I just remove those when doing a really heavy power washing. Reason is water can enter seal of bearing and they then go bad faster or faster.

I like to washer while on a slight hill (front higher than rear) so water flow to rear.

Again; Run engine and go for a drive as soon as done. This with dry water that may have gotten into head ports, valley, spark plugs tubes or wherever.

You're more than welcome!
I can confirm that it is the driver side gasket that is leaking. I just hope to the good lord that it isn't corroded. I'm going to replace both gaskets on the front water bypass. Unfortunately, the procedure isn't illustrated in the FSM so I will have to wing it. Looks like I have to remove the TB to get to it. Any recommendations you can think of? The other crappy thing is I have to remove the water inlet, which takes the grossly expensive FIPG. Any alternative around that? Thanks much!

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Replacing the throttle body gasket is not a bad idea.

Drain coolant from radiator and both block drains, will make job less messy. You don't have to get it all, ~2 gallons should do. If coolant is newer you can reuse, provide you keep clean. Keep clean by attaching 5/16 ID hoses to the block & 1/4" ID (5/16 well do) radiator coolant drains and running into clean jugs. Use a 10mm socket with universal (swivel) and two long extension for block drains.

Make sure to clean spotlessly and don't scratch before assembly or seals may leak.

If you have pitting you can fill with the same FIPG.

You're lucky it's front water by-pass, which is easy to get at.

BTW: ebay has the FIPG cheap. We just don't know if it's legit or bootleg.

Stay warm.
 
I decided to tackle this this evening and decided to take pictures to document and give someone something to look at this tuesday evening. Was pretty straightforward except for the rear 12mm bolt on the passenger side water bypass. The fuel rail that comes across makes it exceptionally difficult to loosen and tighten. You can see in one of the pictures that I used a magnet wand to get it back on. The parts don't look corroded but I tried to get them as cleaned up as I could. A mouse (or rat from the size of the droppings) made a home in the valley at some point so I was happy to have that tidied up with the free access. I also tried to clean up the intake manifold as much I could. Didn't use a new gasket there so hopefully it'll be fine.
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Before:
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After:
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Sudz it up:

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Nice Job. Any picture of old water by-pass gaskets you care to share?

Hate to be the bearer of bad news but looks like you may have one more to tackle. That the rear water by-pass. If lucky it's the hose or heater tee above dripping down. Needs investigation. Clean & watch if it's something new to you.
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Rate took nap!

Funny The WhiteLady came from the West Co Springs area below the Pikes Peak and had mice living in valley chewed up the wires.

Just pulled the intake off a 2008 4Runner and it had a nest also.
 
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Well s***tttt. I can't believe I took that picture and didn't even look closely enough to see it. I cleaned all that dried up stuff off. I think it's from when I did the T's, I spilled a little bit. I'm also banking on that can there isn't any fresh or signs of dried coolant in the valley or off the back of the bell housing of the transmission. So I sprayed it down a tad and will be watching for yet another coolant leak! Thanks for spotting that!
If I remember to dig the gaskets out of the trash before tomorrow I'll take a picture. I didn't think they looked bad enough to be leaking but who knows.
 
The lumping or build-up indicate leak not a spill.
Based on what I can see at rear water by-pass, there is 3 possible sources.

1) Press fit where pipe attaches to water by-pass. It's the one pipe I'm very careful to not pull on when doing the DS heater tees. The pipe is not very secure, and too much disruption it may loose. Only cure is replace of rear water by-pass if that the leak.
2) Is hose at top of pipe may weeping a bit, running down pipe. This also happens when hose disturbed during heater tee replacement. If hose is reused it's generally best to place clamp and hose in exact spot they were in.
3) Often times when new heater tees and new hoses are installed they weep for awhile. This may be from improper placement of clamps or hose just by a mm or two, which can produce a leak. Paying close attention to where factory placed hoses and clamp is key to a good install.

Often times if number 2 or 3 weep will just stop. But usually takes a little adjusting hose and clamps.

As far as leak you fixed on front water by-pass, that gasket will reveal it's leaking spot. If that gasket looked good it most likely was. It is possible it just needed retorquing, but I've yet to see that help. I suppose if leak was found very soon after began from loose nut, re-torque may work and gasket would be difficult to determine leak spot. If gasket failure they look bad.

Time plays a role in how leak location looks. But sign are there if leak was present. Re Torque of these nuts didn't work, nor did they feel loose. So resean factory installed gasket failed is blue sky.
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If your gasket, head or water by-pass showed no sign, leak may have been elsewhere. But take heart, all your work probable stop it.

Driver side rear you can see rear water by-pass, pipe and DS heater tee hose and tee. I did post this picture earlier, and thought it worked well here also.
Rear & front water bypass joint.jpg
 
Thank you for the pictures!!!
On the last picture in the above post, is the heater line that runs right next to the starter and comes all the way to the front is the return line? I need to flush the core.
Thanks!
 
Here is the picture of mine before. I tried to tighten them before I dug into everything but they were cranked.
As for the rear, time and driving will tell if it is leaking. I don't believe the gaskets are leaking, however the one spot it might be is the the tower coming out of the rear bypass (circled in pink in your picture- for color of coolant heh heh).

Again, what's weird is there is not spillage anywhere else except that spot. The front bypass leak dripped all the way down the side of the motor onto the ground, that's how I initially found out about it.

If the rear is leaking at that spot, could I seal it with something instead of tearing into that whole animal?

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Rear & front water bypass joint.jpg
 
Thank you for the pictures!!!
On the last picture in the above post, is the heater line that runs right next to the starter and comes all the way to the front is the return line? I need to flush the core.
Thanks!
That is return line on PS.

Notice in my video, I'm back flushed by sucking with pump. This keep my makeshift pump fitting & hoses from blowing apart.
 
Here is the picture of mine before. I tried to tighten them before I dug into everything but they were cranked.
As for the rear, time and driving will tell if it is leaking. I don't believe the gaskets are leaking, however the one spot it might be is the the tower coming out of the rear bypass (circled in pink in your picture- for color of coolant heh heh).

Again, what's weird is there is not spillage anywhere else except that spot. The front bypass leak dripped all the way down the side of the motor onto the ground, that's how I initially found out about it.

If the rear is leaking at that spot, could I seal it with something instead of tearing into that whole animal?

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That old seal does look a bit rough, but inconclusive. I would need to see both sides and close ups. Along with metal surface it seal on water by-pass and head.

Yes your circle is the pipe pressure fitted into the rear water by-pass. Over the years there has been a good number of threads on that pipe. Only sure cure is replacement rear water by-pass which comes with pipe pressure fitted, that I know of.

But clean and watch closely, as coolant may be or have been dripped from hose fitting on the pipe or even hose fitting on tee. Trick is to get perfectly clean, then watch to catch and see that first drip as it appears. Keep in mind, fluid move down and back in most cases.

It's been my feeling that this pipe loosen at pressure fitting because it was moved while replacing tees, more so than just failing.
 
So the rear water bypass is for sure leaking st the pressure fitting. The part isn’t too expensive, have any idea if I can get to it without taking off the manifold? Would really love not to have to do that. There looks to be a good bit of wiring on top of the bypass too.
 
I think you can. Seems I've seen post(s) where some have done without removing intake, and it sure looks like you can. The wire housing block will be in the way so you'll need to pull bolts, 2 of them IIRC. There are other bolts, but I don't recall on the non VVT like pictured. You need to then move it back just a few inches.
01 LX 215K (1)a.jpg

They look like 10mm bolts holding wire housing.
Z 01 LX470 day 8 Starter 031.JPG

Note: When installing don't put side to side pressure on that tube of new water by-pass. Or you may cause to leak at same point again.

Try without doing following first, but you may find easier: Disconnecting the wire housing retainers that support the wires along each side of the engine, which may give some more wiggle room with wire housing block. It may also give you additional wiggle room if you disconnect all of it's wires from the engine (injectors & coils). Try without first, but disconnecting wires will make pushing back block housing out of the way easier. IIRC 4 wire blocks held on transmission by a bracket, which has one bolt holding it. Removing that bracket retaining bolt may loosen up the area some more, but probably not necessary either. Here's one more bolt you shouldn't need to remove, but I'll point out just in case the starter white wires housing block hang you up.

Bolt comes through from rear to secure white wire housing block to starter.
Z 01 LX470 day 8 Starter 030.JPG


Keep in mind at 200K it's not a bad idea to replace starter contacts & plunger. With rear water by-pass off those PITA starter bolts are a little easier to get at. So consider rebuilding the starter and replacing the intake gasket.
If you look in Whitelady opening post (near the bottom), it has links at bottom that will help you with these extras. Below are some of those links:
Best starter for the money today?

If you really want to get after it you could; send the fuel injectors out while in there for servicing, and replacing the FPR. But those can be done without removing intake manifold, easily at any time. When to Clean or Replace fuel injectors
 
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