rear timing belt case coolant leak 7mgte

[san supra]

i am 95% sure my timing belt case is leaking and my question is, can you replace the gasket without removing the head?
could i break torque on the head and scrape the rtv off the head and timing case and then reinstall with new rtv and then retorque?

my t case bolts loosened up and i think it ruined the gasket, when i tighten the nuts it almost stopped the leak but its getting worse now.

i checked the 90 degree hose on the t-stat housing and the coolant line that goes to the back of the motor

 

[CyFi6]

If your timing case was leaking, you would be leaking oil not coolant. Unless of course it is cracked or if the water pump is leaking. You said you checked the line that goes to the back of the motor, are you sure it isnt leaking there? Its got a flange and two nuts that hold it ot the rear timing cover, under the exhaust manifold. Thats a pretty common place for a coolant leak.

 

[san supra]

oil? i guess i didnt look too much into it. that makes me feel better

i have checked that line many times and i haven't seen anything. its not even wet like it was in the past when the 90deg hose leaked on it.

why would the leak slow down a bunch when i tighten the t-case nuts by the water pump and the water pump is dry along the botom.
Thats why i thought it could only be the t-belt cover.

 

[san supra]

Ok, i have now replaced the coolant block gasket and the water pump gasket. There is no change in the leak and i still think it is the rear t-belt cover.
While i had the water pump off you can clearly see a gasket inside the water pump.
The 90deg hose is not leaking and neither is the hard line gasket in the back of the water pump.

Soooo can i replace the gasket without taking the head off?

 

[IJ.]

Almost impossible due to the dowel pegs in the front ofe the block, you'll end up with a head leak a pan leak and a timing case leak.

 

[san supra]

FML!
i just rebuilt this motor

anything else you would try to do first?

 

[CyFi6]

Ya the timing cover gasket does seal coolant for the main water pump passage, but its not extremely likely it would just be leaking there. I would make 100% sure that is where you are leaking before you go pulling the head and pan just to do that gasket. Get a cooling system pressure tester, it will make it MUCH easier to spot the leak.

 

[san supra]

http://cygnusx1.net/Supra/Library/Gaskets/graphics/11312-42010_h.jpg

the large opening sits behind the water pump and two of the pumps studs go threw it

 

[IJ.]

FML!
i just rebuilt this motor

anything else you would try to do first?

No, the time you spend fucking around and fail could be used to do it properly.

 

[san supra]

so pulling the motor is the best way?

 

[IJ.]

I would, it'll be easier in the long run.

 

[san supra]

is sifi6 correct about the gasket not going behind the water pump and if so what was the gasket i saw on the inside of the pump.

 

[IJ.]

There IS a gasket between the timing case and block that seals Coolant and Oil.

 

[Poodles]

And you'll more than likely end up mixing the two causing damage if it's not fixed properly.

 

[san supra]

thanks everyone

 

[san supra]

i didn't want to start a new thread.
my related question is, what should i put on the t-case gaskets?
i was thinking rtv

last time i put some brown liquid non-hardening stuff with a brush. I believe most people use it for water pumps.

 

[dragracer]

Get this gasket from Toyota. I built one motor using FelPro (always were good on my old muscle cars), and I had problems with several.

If both surfaces are CLEAN and smooth, you shouldnt use any sealers. In theory that is. Sealants will soak into the gasket and change the sealing properties.

What ever you do, dont use a scotchbrite wheel (or something similar) on a grinder to clean the gasket surfaces. Scrape them clean without gouging. Scotchbrite on aluminum will ruin the mating surface. I guarantee the surface will not be flat afterwords.

Just mt two cents worth

 

[Poodles]

They make gasket remover in a spray can that will dissolve the old gasket as well.

 

[IJ.]

Genuine Toyota gaskets have a coating of sealer.

 

[san supra]

good info
the gasket i have is felpro but i have to use it (no time)

thanks again