Back of block Coolant leek

Ok so i have a coolant leak from the back of the block it is not the heater core hoses, where else could it be, how easy is it to replace, i have the box out, anyone got any tips on where to start, cheers Baz

 

by the way the under plenum bypass has been completed

 

Turbo coolant lines. Fun.

Andy loves changing them You can do it with the plenum and gearbox on but they are not fun at all.

 

so you are saying it is most likely them or it is them, how many other possibilites are there?

The box is out so does that make it easier?

 

you and me both buddy.

 

Likely them. Pulling the box will give a lot more room but is not required. if you are doing the clutch soon, then I would do it at the same time (but soon).

 

box is out, car is on a hoist, lol

 

Last Year this happened to me

I took my zed down to the garage (about 1km) and came back home and parked in the driveway, not the garage, as I was going straight back out again. Which was lucky for me, as I walked past the front of the car and noticed steam coming from the back of the bonnet. So I popped the bonnet and went to have a look and then I noticed a huge pool of coolant appearing from under the passenger side of the car ( I had blown the bastard hose at the back of the engine ).

To replace the hose my mechanic dropped the gearbox to get at it , others I think have removed the plenum to get at it.

Have a look at this link
http://www.aus300zx.com/forum/showthread.php?t=281774

Gary

 

There's a small hose that comes off the passenger side heater bypass hard pipe, which then connects to another small hardline, which then connects to a 4 inch or so long piece of hose which runs along the back of the motor on the passenger side before it connects to a hardline which follows to the turbo water lines, I think this hose is about the only one I haven't bother to replace engine in since it's an absolute pain in the ass to get your hands to.
For the sake of your sanity I hope it's not this one lol.

PS: When I was a Z noob I took the car to Nissan to replace a holed turbo water line, cost $370 or something ridiculous like that - I got reamed!

 

Ok so it is drivers side, so it is not the passenger turbo line, any other ideas people, the mechanics have ruled out head gasket as a problem so not that

 

There's a little right angled coolant hose for the turbo inlet. If you've done the bypass properly, this would be the only hose left to change on the drivers side. Easiest to remove the master cylinder as I couldn't get my paws down there without removing it.

Where is the car, I can come point it out for you.

 

car is at the mechanics in manly vale, bypass was done by zed4life so it was done properly

 

manly vale...too lazy to go down there thats 20minutes away!

Tell your grease monkey to put the car on the ground, look at the master cylinder, diagonally right towards the plenum and down you'll encounter the hose. Replace it with a 4" piece of 8mm heater hose, pressurise and test.

Why doesn't he just pressurise the whole system and look for the leak? What sort of backyard grease monkey is this?

Oh and while the box is out get him to replace the hoses that run down the back of the block on the passenger side from the heater pipes to the turbo, these are easiest with the box out, and an absolute PITA with it in.

 

i was able to replace this hose with plenum off

its a bastard of a job but not impossible.....make sure though, when putting the new hose back on not to kink it and restrict coolant flow, is easy to do if your piece of hose is too long.....

 

They said they could not find it, so yeah not sure, but hey i am sure they will get it sorted

 

yeah, you don't need to remove the plenum to change any cooling hoses (except of course those under the plenum) and you can do the bypasses with the plenum on. That hose is accessible with the master cylinder removed, which is by far easier than the plenum. I think 90TTZ reckons he could do it with the MC in place and plenum on, but I didn't screw around, i just ripped it out. 2 bolts and to fittings, then you have unimpeded access to it.

 

yeah i had the plenum off anyway for other things.....master cylinder off would yield the same result access wise, or close enough anyways.....

 

I tried for several hours to get to mine without removing the master cylinder, only resulted in frustration and skinned knuckles. After I bit the bullet and got the MC off it was fairly straightforward, just is a prick having to bleed the brakes when it's done..

 

They couldnt find the coolant lines for the turbo ?? or the leak??