Water By-Pass Joint leak (1 Viewer)

[bgflyer34]

I've finally located the slow coolant leak on my 2004 GX (144K). The leak is at both gaskets on the "water by-pass joint." See attached picture from the FSM.

The FSM doesn't specifically mention replacing the Water by-pass joint (at least what I've found so far), it only mentions replacing the water pump. My question to anyone who knows...do I need to remove the timing belt to get to water by-pass joint? Has anyone had a similar issue?

The water pump and TB were done at 90k...I can only assume the gaskets on the Water by-pass joint weren't changed.

 

[GXO]

Not sure if you can do that without pulling the intake. Pretty sure you can do it without touching the wp/tb

 

[GXO]

Oh...and if you pull the intake put a starter in it to save headaches later.

 

[scooterp7]

What did you end up doing? I found the same leak today. It looks doable without pulling the intake, only the throttle
Body. Thanks.

Scott

 

[bgflyer34]

Out of curiosity, how many miles do you have? What year is your GX?

I took it to the shop and had it fixed along w a new starter. The mechanic pulled the intake to do the job.

Heads up, if you pull the intake, the FSM calls for new fuel injector gaskets when they come out. The Indy mechanic I used didn’t do this and it resulted in a fuel leak.

 

[scooterp7]

05 with 155k on it. Thanks for the tip on the fuel injectors.

 

[vwynn]

ive done this job to replace the REAR bypass joint... but also replaced the front. No need to remove timing belt.... i actually did my timing belt a week or so before doing this job so i know.

Regarding the front and rear the intake manifold needs to come off. Pretty straight forward with no "gotcha" things in the way. Search up youtube for GX470 SAIS replacement and you will be on your way.

The front gaskets are painless but messy if you dont drain your coolant before hand... so do that. Make sure you clean off all old gasket that happen to bake on the housing... mine was 25% baked on and required me to go in there and scrape it with a razor blade and sand paper.

The rear gaskets requires god to calm you down... In order to lift the rear bypass joint off you have to unbolt the check valves in the rear + cut off the air hose in the pump... (buy replacement hose!)

My recommendation

- Buy all the 4 gaskets (2 front 2 rear)
- Buy air hose tube for the air pump
- Buy intake manifold gasket
- But Throttle body gasket

replace said above.

WOOPS... typed all this and realized you are non VVTI... do you dont have to worry about the check valves in the rear... makes it much easier to do

 

[vwynn]

05 with 155k on it. Thanks for the tip on the fuel injectors.

You might be able to pull the whole manifold with injectors out... i did it on mine (2006)

 

[scooterp7]

Mine is a VVTI engine. The o-ring on the back of the front bypass is what is leaking. It connects to the metal heater pipe that runs down the passenger side under the intake. I should not have to remove the the bypass assembly. Intake gaskets, tb o-ring, bypass o-ring and starter rebuild parts. I am putting a SAI bypass on, so no need to mess with that
Stuff. I may order the front bypass gaskets just in case.

 

[vwynn]

I highly recommend replacing those bypass gaskets only because you will have access to them once everything is out of the way. Might as well have a small headache now instead of a huge one later.



Video i used for removal... best video to date.

 

[scooterp7]

Thanks

 

[arg143]

ive done this job to replace the REAR bypass joint... but also replaced the front. No need to remove timing belt.... i actually did my timing belt a week or so before doing this job so i know.

Regarding the front and rear the intake manifold needs to come off. Pretty straight forward with no "gotcha" things in the way. Search up youtube for GX470 SAIS replacement and you will be on your way.

The front gaskets are painless but messy if you dont drain your coolant before hand... so do that. Make sure you clean off all old gasket that happen to bake on the housing... mine was 25% baked on and required me to go in there and scrape it with a razor blade and sand paper.

The rear gaskets requires god to calm you down... In order to lift the rear bypass joint off you have to unbolt the check valves in the rear + cut off the air hose in the pump... (buy replacement hose!)

My recommendation

- Buy all the 4 gaskets (2 front 2 rear)
- Buy air hose tube for the air pump
- Buy intake manifold gasket
- But Throttle body gasket

replace said above.

WOOPS... typed all this and realized you are non VVTI... do you dont have to worry about the check valves in the rear... makes it much easier to do

I know this is an old thread but I’m hoping for some help. I’m at the point of removing the air pumps from the back of the rear bypass but can’t get them out because they are running into the firewall. Any suggestions? Thanks!