Help with water leak...

[Chris Wire]

OK, last night I finished plumbing the radiator, jacked up left side, filled to top of radiator, jacked up right side and filled to top of filler neck. All is good, right? So as I am on to other (worse) jobs like wiring the tach and shift lite, I notice a small trickle of water running out from under the car. OK, loose hose or a water port I forgot to cap off, not to worry. Well upon further inspection, it appears that the water is running out from between the intake and engine right underneath the outside intake ports. In looking at the old engine on the ground, there is a rectangular port under the ports front/rear but the gasket on the old motor had them sealed off. There does not appear to be a corresponding port on the intake to match up with it.

My question is: is this port normally sealed with gasket maker between the gasket and engine? The factory manual makes no such recommendation, and the old gasket had no additional sealant on the old motor. It looks like I'll have to pull the lower intake back off, but I'd like to have a plan before I begin. Open to any and all suggestions.

TIA,

Chris

[Redshift]

Sorry if this is a dumb question, but what engine/car combo are we talking about here?

[C. Ludwig]

On the NA cars there is no water that passes from the engine to the intake at the junction of the LIM and the engine. The water can't be leaking from there unless:

1) You've used turbo rotor housings and didn't plug the coolant ports. We won't go there.
2) It's actually leaking from between the rotor housing and an iron. I hope you don't have to go there.


It's more likely leaking from above and you just haven't found the origin.

[Chris Wire]

Sorry if this is a dumb question, but what engine/car combo are we talking about here?
[/b]

Not a dumb question at all, since I totally zeroed out the initial post.

1989 NA 13b RX7

Sorry.

Chris,

Housings are not an issue, they're identical to what came out of the car.

This pic is a starter for what I'm referring to, although this lower coolant port is obviously below the inner intake ports:

http://home.iprimus.com.au/bluey3/portsPage/4inlet1.jpg

Here is what I'm really getting at. I hope this helps clear it up:

[C. Ludwig]

That's not a coolant port. It's an EGR port. Pull the intake off and pressurize the system. You'll quickly find the leak.

[Chris Wire]

Thanks for the help, Chris.

I tried to fill it again last night and above a certain level, the water leaks out quickly. When the drip stops, the radiator is still full, which leads me to believe that the leak is somewhere up high. I'll check it this weekend.

[C. Ludwig]

I have a pressure tester like this one. It makes finding these kinds of leaks a lot easier. Though, if it's running out that quickly, it shouldn't be that hard to spot.


http://cgi.ebay.com/ebaymotors/SNAP-ON-TOO...sspagenameZWDVW (http://cgi.ebay.com/ebaymotors/SNAP-ON-TOOLS-RADIATOR-COOLANT-PRESSURE-TESTER-SVT-262_W0QQcmdZViewItemQQcategoryZ43989QQihZ013QQitem Z230156990924QQrdZ1QQsspagenameZWDVW)

[Chris Wire]

Yeah, one of my co-workers has the same setup. I may borrow it this weekend.

Cross your fingers for a leaky hose or gasket! :023: The last thing I need is to have to yank that motor back out.

[Chris Wire]

Points for Ludwig!

I took your advise and borrowed the cooling system pressure tester and found the leak. When pressurized to 15 psi, the cap I put on the throttle body port on top of the motor started pouring water out. The pressure made the leak easier to locate, when it wasn't pressurized the leak was slow and harder to see. Either way I was going to pull the upper intake, but this way gave me piece of mind a lot sooner.

Problem fixed......now on with the show!

P.S. The pressure tester did show some minor leakage at various hose connections, one of which I had to double clamp. (That hose will be replaced with better stuff once I know the motor is up and running.)

Thanks again Chris.

[C. Ludwig]

Take my next piece of advice and ditch those caps before they cost you an engine. Do it now before you run the car. I lost a good engine because I never got around to replacing those caps with a proper threaded plug. The rubber cap came apart, the coolant spilled out in short order, and the engine got warm enough to detonate the rear rotor. It's very easy to drill and tap the rear iron and water pump for NPT plugs, even in the car. 1/4" NPT on top and back of the water pump and I think it's 3/8" NPT for the heater outlet on the side.

[Chris Wire]

Point well taken. I'll definitely look into doing just that. Thanks again.