coolant leak from transit tube (metal)running through belt tensioner/pulley assembly

[commodoredave]

VTII V6 no turbo or Scharge
Coolant has started leaking from near where the rubber hose joins the metal through pipe in the tensioner assembly. The rubber hose comes in from the upper heater tap port. Hose is fine as is the clamp. An O-ring rubber seal( not visible without removing the tensioner). prevents leaks but the seal seems rather delicate and the metal tube needs a quarter turn to fix it in.. Used a rubber mallet to tap the tube back into place and this seems to have temporarily solved the coolant leak. Has any had this problem? How did you solve it? There is a marker notch on the tube does anyone know exactly the optimal posotion of the notch? Could the notch position relate to the optimal positioning for the pipe and thus the integrity of the seal?

 

[Immortality]

If you have disturbed that O ring seal and it's leaking it's time to replace the O ring. Make sure to clean all the surfaces and use some sort of lube when re-fitting the O ring to lessen the chances of pinching it and damaging it causing another leak.

Worst case scenario, pull it out, clean it up and use RTV but good luck getting it back out in the future.

 

[Grimes]

You need to coat the o ring in a smear of rubber grease before you push the tube back in, otherwise it will resist the way you’ve described. If you simply pulled it out and re-used the old o ring, it will start leaking again.

 

[SLIfox]

rubber o ring flattens on two sides as it gets old if it's leaking it's definitely going to need to be replaced along with the other metal coolant pipe around it, as it'll be next to go too.

 

[commodoredave]

If you have disturbed that O ring seal and it's leaking it's time to replace the O ring. Make sure to clean all the surfaces and use some sort of lube when re-fitting the O ring to lessen the chances of pinching it and damaging it causing another leak.

Worst case scenario, pull it out, clean it up and use RTV but good luck getting it back out in the future.

The gentle rubber mallet tap back into place seems to have fixed the coolant leak for now. Even so it needs another o-ring seal. Its a while since I changed the belt tensioner assembly. Is it possible to slide out the tube without needing to undo/remove the whole belt tension unit.?

 

[Grimes]

It is, but then you won’t be able to clean up the seat where the o ring goes. You run the risk of putting in a new o ring and having it seat on some crud. I’d take the time to remove the tensioner so you know it’s done properly.

 

[losh1971]

Any grease will do. Orings are safe with oil, grease and petrol. Viton is better as it handles more heat.

 

[commodoredave]

It is, but then you won’t be able to clean up the seat where the o ring goes. You run the risk of putting in a new o ring and having it seat on some crud. I’d take the time to remove the tensioner so you know it’s done properly.

Use good quality coolant and flush regularly. When work needs to be done it is surprising just how clean things are inside.

 

[vxcalais_01]

You need to get a hook and clean the surfaces where the O-ring sits, especially is sealant was used prior. I know O-rings should only be greased but Holden used the O ring in such a poo location as well as the one that goes in the front I coat them with some Permatex Grey or Wurth Super RTV. When you push that pipe on, push it until the bolt hole and metal frame line up on the other end. Then give it 2 hours for the RTV to set. Fill up and off you go. You can also take off the thermostat housing to look in from the other side to see if pipe has gone it correctly. Without using grease or sealant, it can nick the o ring and cut it. Again don't blame yourself for the creative manner Holden Engineers decided to do this.