vz commodre alloytec v6 water leakage

[alloytec sludge]

ide send pics but dont know how

 

[Group C]

Was a thread on here not long ago about water leaking down back of engine turned out to be something in front not 100% sure what but mech's where quoting heads turned out to be much smaller and cheaper maybe search/or someone may remember what it was

 

[alloytec sludge]

http://forums.justcommodores.com.au...-mechanic-w-sydney-blue-mountains-area-3.html

 

[marko1au]

replaced the "o" ring in the engine pipe that goes into the thermostat ...... i thought that coolant only leaks when its cold not hot ........ will explore welsh plugs ........ checked tonight when i got home from work about a 30 k drive and all looks good, couldnt see any signs of leaking ...... but ive been tricked before ....... i dosnt seem to be a fast leak more intermittent leak if its possible to have one of them ....... will check coolant level tomorrow night if i get home early enough, and i must admit that even before replacing the thermostat last weekend i hadn't noticed losing coolant other than the stain on the bell housing.

 

[marko1au]

i should of stated that i hadn't noticed losing coolant after i fixed the front inlet pipe leakage

 

[Group C]

Silly Question but have you or anyone else pressure tested system??

 

[chriso-k]

Ok, here we go. The thermostat housing on the VZ& VE Commodores' is a bitch to get to. More so on the VE because there is even less access. If your thermostat area is still leaking , I'd say you've possibly upset something during the repair. There is three areas of interest here. The first > the actual thermostat housing gasket itself, the two "O" rings, for the stainless steel heater pipes, at the back of the thermostat housing, and the big "O" ring on the end of the upper radiator hose, stainless steel transfer pipe, which slips into the thermostat housing. Things you need to think of > did you clean the thermostat housing gasket mating surfaces properly? It's so restrictive in this area that you need a mirror to assess the end cleaning result. Did you slip the thermostat housing into the transfer pipe smoothly and correctly? Lastly, I'll disclose a trick of the trade for Just Commodores members.. The heater pipes at the back of the thermostat housing are held on by two little bolts. But these little buggers are near impossible to get to in such a confined area where you're working by feel rather than sight. So, before installing the thermostat housing on the back of the engine, discard the two little bolts and install two little studs in where the two little bolts would go. Replacing the little bolts with studs and nuts, ensures a quick installation alignment of the heater pipes to the back of the thermostat housing and, guarantees no distortion or pinching of the two sealing "O" rings on the housing. The "O" rings sit in a recess at the back of the housing and if they're installed offset in any way, they will be pinched. Hope this helps. Chris

in the last two weeks i have replaced the water pump, the front inlet seals and noticed that there was coolant coming from the rear of the motor. so this weekend i set about replacing the thermostat housing, thermostat and heater hose seals and after 5 hours it still leaks from somewhere on the rear of the motor. i can see coolant on the left hand side on the bell housing ......... what have i missed ????? where else can it leak from ...

 

[diysv6]

I have made a link to a contributor who has an image of the two welsh plugs in the valley of the alloytec engine block.

Many thanks to sus steven for his information.


http://forums.justcommodores.com.au...2004-2006/198404-rebuilding-190-alloytec.html

 

[marko1au]

ok ....... replaced a water pump about six months ago ..... at my last service ( about 4 weeks ago ) my mechanic noticed coolant sprayed around the front of the engine bay again, did a pressure test (keeping in mind the engine is still warm) left the tester hooked up for about half an hour while he did other service things and the reading did not change so we determined that the water pump was the issue, so that weekend i replaced it (couldnt see anywhere that it was leaking from) all good for a couple of weeks and the i started to smell coolant. again coolant in the front engine bay so i decided to replace the seals in the front inlet pipe,i could see where it had been leaking from so i thought i had the problem licked ....... two weeks later guess what ???? i could smell coolant again and this is when i noticed the dry coolant stains on the bell housing passengers side ....... so ..... time to replace the thermostat housing. i bought the replacement kit from gmh with the extra o rings or seals whichever you prefer and set about replacing these ...... 5 hours later ...... and a lot of abuse and cuts,abrasions i thought id fixed the problem (also note that i couldnt see anywhere after removing them that the thermostat housing was leaking from, nor the heater pipes) on start up i had coolant back on the bell housing ( this is the first time i had seen it wet ) i felt around the back of the motor (at this stage my arm was used to doing this) i could feel dampness on the very top of the bell housing (paas side) directly behind the head, but i could not feel it anywhere else ....... so i used a rag so i could press it into the places my fingers couldnt reach and it came up dry (around the thermostat areas) so im at a loss to work out from whence it came

 

[alloytec sludge]

it must of failed . those o rings for heater pipes have to go over the pipe then fit in housing not sit in housing first . also people are saying that front one can leak and travel to the back by traveling in the valley between heads