Front Water Bypass (solved with write up)

[Rolocado]

That’s a good question I’d like to know as well. Also, what is FPR?

 

[2001LC]

FPR = fuel pressure regulator. You'll see some talk about the FPR in post #20 When to Clean or Replace fuel injectors $100 part easy to replace at anytime.

Replacing the rear water by-pass without removing intake, I've never done. As I said I "think" you can. Root around on the forum and you may find some that have. To me it looks like it can be done easily, on the non VVT engine. If you really don't want to pull intake as you said, try without. Then if it gets to difficult just pull the intake to get out of your way.

Pulling intake is no big deal. The biggest part is cleaning the heads and intake for new gasket, while keeping crud out of intake ports of head. I'd guess 2hr without intake removal, 5hr with.

You'll need to drain block & radiation down about a gallon each. This is necessary if pulling intake, and not a bad idea even if not.

 

[2001LC]

@Rolocado I've been looking for a picture of the back of intake manifold, for one more bolt you may need to remove. I've don't recall nore can I find a picture of the non VVti manifold. But if there is one more bolt it would be around same place as on the VVT plastic intake manifold.

Here the one on the VVt for reference. It's on DS near the heater tube that is leaking.

 

[Rolocado]

@Rolocado I've been looking for a picture of the back of intake manifold, for one more bolt you may need to remove. I've don't recall nore can I find a picture of the non VVti manifold. But if there is one more bolt it would be around same place as on the VVT plastic intake manifold.

Here the one on the VVt for reference. It's on DS near the heater tube that is leaking.
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Awesome, thanks much! Haven’t paid attention to it with the holidays but I’m going to look at parts costs and see what’s worth doing. Thanks for the pics!

 

[NoVaGator]

looks like I'll be doing this job soon, thanks to LC2001's helpful troubleshooting today!

 

[GVegasG]

I think I have a similar issue - leak at least the front by pass joint.
I noticed a coolant under the car which was coming down from the top - side of the engine on driver side, ac condenser, axle and ground. Also noticed coolant in the engine valley.
I got a coolant compression tester and it showed an active leak from same places and same flow.
I definitely think front water bypass joint seals are not good. However I wonder if that is it. I can’t tell if rear one is leaking or not. How can I be sure, perhaps using a mirror?
The pink spots in front of the intake manifold is something I don’t remember ever seeing it.
I just hope it is just a front bypass joint and no other major issues such as head gasket.
I just got the car and don’t know the history. I am not sure if I am going to keep it or not yet and I know once I start, I will want to take care of everything like starter, WP, TB etc.

 

[2001LC]

I think I have a similar issue - leak at least the front by pass joint.
I noticed a coolant under the car which was coming down from the top - side of the engine on driver side, ac condenser, axle and ground. Also noticed coolant in the engine valley.
I got a coolant compression tester and it showed an active leak from same places and same flow.
I definitely think front water bypass joint seals are not good. However I wonder if that is it. I can’t tell if rear one is leaking or not. How can I be sure, perhaps using a mirror?
The pink spots in front of the intake manifold is something I don’t remember ever seeing it.
I just hope it is just a front bypass joint and no other major issues such as head gasket.
I just got the car and don’t know the history. I am not sure if I am going to keep it or not yet and I know once I start, I will want to take care of everything like starter, WP, TB etc.

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Your pictures of small black hose circled in black, is vacuum hose for EVAP system. Under it is the throttle body, which has a very common and very small weep from a cap. This is not your coolant leak.

The water bypass front BK1 mounting point, is not leaking. Or so I can't see a puddle or pink crusty. This is not to say, it's not leaking from mount point on inside valley area.

The coolant in the valley and on front side of BK1 block. Without signs of leak on top side of engine. Make me think either a blotched water pump install. In which the small O-ring of the water cross over pipe, and water pump seal on BK1 side are both leaking. Or A head gasket of BK 1 both in valley & outside of head.
But if your parked where front of engine lower than rear or at and angle. We could have leaks coming from other points. Like heater tees, their hoses and pipes. Where coolant running/travel forward.

Study the picture in page 1 of this thread. I've some where I point to all water leaks points in valley. This will help you know where to look an at what your seeing.

You'll need to look deeper into valley, studying all 4 points of the water bypasses front & rear joint/mounting point where they attach to head. Also the water cross over tube o-ring where it enters the water pump at front. Also heat Tee hoses and the pipes from water pump (cross over pipe) and rear water bypass BK1 (driver side).

Addition the head gaskets. With air pipe off, a flash light and mirror you can see about 60% into valley under intake manifold. But to really get a good look. A bore scope will be really helpful. Drain snake camera (bore scope) that hooks to a smart phone, are ~$20. Their not great, but will get the job done.

Additional study the head gasket on outside of block, both sides. This can be done with skids off. Just get a flash light and look up from below. You can see 95% of where cast iron block meets aluminium heads.

Also stud the front of engine starting at lower timing cover weep hole. Also look below both heads timing covers, at iron block case.

Follow leak from bottom up. They all start at a point.

Get some good picture and post them.

BTW here's what head gasket leak looks like. Which we hope is not your issue.

Old leak head gasket leak, where likely stop-leak used and was not Toyota coolant at time of leak.

 

[GVegasG]

I looked into the leak bit more yesterday and today. Before the car was parked front higher than rear - driveway. Yesterday I changed the position where front is lower than rear. Engine valley still has plenty of coolant.
When I did the coolant pressure test today, it leaked again with similar coolant path - over ac condenser and down on the driver side. However this time it also leaked from front bottom coolant whip hole.
I think your right on about leak not coming from water bypass but rather from the pipe going into the water pump. It is time to replace water pump since last job was 100k ago.
Thinking about it more I think WP and TB job will fix the leak. Thanks

 

[GVegasG]

I drove just a bit today to a stop sign and back. Noticed leak from a different spot at the bottom but I think it is all tied together.
After the short drive initially it got parked in driveway front higher then rear. I assume engine valley filled up and it went to the back and down.

 

[ninedude]

Apologies for resussicating this but it may help someone in the future:
What are the part numbers for the front bypass gaskets? I have looked for a long time and come up empty... thank you!

 

[2001LC]

Apologies for resussicating this but it may help someone in the future:
What are the part numbers for the front bypass gaskets? I have looked for a long time and come up empty... thank you!

I kind of avoid giving P/N. I give you the ability to find your own. "Teach a one to fish"

Many variation and many P/Ns, through the years and where in the world built for use.

Type in your VIN#, at: www.partsouq.com It will bring up your vehicle, even the colors. You love this.