help me find my coolant leak!

[90MTXSHO]

Alright - some time ago, my car sprung a leak. It really smells of coolant, both with the heater on and off, vents open or closed. I can open the window and get some relief, but I don't like whiffing coolant whenever I drive.

Here's what I know. The leak is coming from the back of the engine, dripping on the back cat, and sometimes vaporizing, thus the smell, or dripping on the ground. The temperature of the engine runs hot until I put more coolant in...then it's stable. There are no odd noises, but the car does feel a little hesitant at first, until around 4k when it goes back to normal and flies. I was just under the car and noticed that there's a little wetness near the middle axle coming from the tranny, but the two I believe heater hoses (near the top of the engine, just behind the intake?) are dry, and the water pump feels dry (when I run my hand under the pully against the block. The car hasn't had symptoms of a bad CPS, which leads me to think - after all this time of not killing - it isn't the water pump. Finally, the head gasket's in tact (just to throw that out), no leaking from it.

What the **** am I missing here? And more importantly...how much is this going to cost me to fix?! Thanks!

 

[projectSHO89]

Here are two things to check:

1. Use an inspection mirror and a flashlight to THOROUGHLY inspect both of the heater hose to heater core connections. These have been known often to leak and to spray coolant into the heater box through the holes in the firewall. The leaking can be very difficult to find unless you use the mirror and light.

2. See if there is an evidence of coolant dripping from the drain immediately below the lower AC line connection. Any coolant dripping from there (make sure you do not confuse it with the condensate from the AC since it's the same drain) is coming out of the heater box. If there was absolutely no evidence of the leaking from step one, you likely have a leaking heater core.

If you're lucky, it will be just a matter of tightening the heater hose clamps. If the diagnosis is that the core is leaking, then you are looking at a job that a shop will charge 8 to 12 hours for. The core is 20 bucks at Autozone. I just replaced mine this last week for the 2nd time (don't ask..) and it's not any fun.

Just one of the reasons I got my SHO for 200 bucks...

Steve
89

<small>[ September 29, 2002, 08:21 PM: Message edited by: projectSHO89 ]</small>

 

[SW SHO]

Check the hoses coming down from the Throttle body. I don't what they are called, but there are two, one kinda above the thermostat and the other in a bit and on the right side for the TB. Take the cover off your air box, get a flashlight, let the engine get to temp, and manually flick the throttle up to 2.5-3k rmp looking in the direction of the TB.

I ended up replaceing both of those hoses and it fixed my mystery leak!

 

[rangerj]

90MTXSHO,

Looking at the back of the engine, that is looking over the left front fender, there are three small hoses connected to the throttle body. At the other end of the heater hoses, the metal pipes have a short piece of hose that connects to the engine below and to the right of the T-stat.

There is a shot piece of hose that connects to the pipe that runs from the water pump to the thermostat and it connects to the engine. This short piece of hose is of large diameter, about 2 inches.

If these are all original hoses on your 90 SHO, then any one of them could be leaking. A leak from any one of these would flow down onto the transmission, and could easily end up where you found the wetness.

You may want to try watching for the leaking fluid just after you shut down the engine. The fluid is still hot, and under pressure from expansion of the fluid. If there is a pinhole leak in a hose, it should show up at this time.

If you are smelling the anti-freeze that strongly in the car, you may want to check for wetness on the carpeting under the dash. (heater core)

All of the hoses I mentioned, with the exception of the large dianeter short hose, are pre-formed hoses, and may be available from very few sources.
I was able to get the heater hoses from a Ford dealer parts department.

The other hoses were from SHO Nut. The short piece of hose clamped onto the metal heater hose pipes can be removed and replaced with regular heater hose and clamps, as long as the pipe is not rusted through.

If these hoses are original, it would be a good idea to replace them for two reasons; 1, the rubber deteriorates with age and they are 13 years old, 2, they are pre-formed and not readily available from the local auto parts store, and 3, they may not be available in the future.

Here is a list of the Ford part numbers;
E9DZ-8548-A Throttle body to block near oil filter
E9DZ-8548-B Short "C" shaped hose at oil filter
E9DZ-8548-C Small hose on throttle body
E9DZ-8548-D " " " " "
E9DZ-8548-E " " " " "
E9DZ-8548-FA 2 1/2 long X 2 inch ID Behind the T-stat (to the right)
E9DZ-18472-D heater hose
E9DZ-18472-E " "

You can get prices from SHO Nut, and/or Ford Parts on line. Hope this helps, rangerj

 

[Red Raspberry]

If you can smell it while driving it's got to be the heater hoses. Just get some 5/8" and 3/4" bulk hose and a 5/8 x 3/4" adapter.

You can replace all the hoses on you SHO with bulk hose with the exception of E9DZ-8548-B Short "C" shaped hose at oil filter and E9DZ-8548-FA 2 1/2 long X 2 inch ID Behind the T-stat (to the right).

A lot cheaper than the manufactured ones.

 

[90MTXSHO]

Sweet! Thanks for the help guys. As soon as I get a chance (most likely next friday or saturday), I'll be outside hunting. I noticed there was a little wetness near what looked like an A/C line, but it had rained last night, so it could've just been from that. I'm really hoping it's a line and not the core (...how hard would that be to change myself, with little skill?). Thanks again!

 

[Red Raspberry]

"not the core (...how hard would that be to change myself, with little skill?). "

Not an easy job at all. Maybe a 2-3 dayer if you've never done it before.

 

[90MTXSHO]

ah joy!

i just checked out side. couldn't find a leak at all...carpet's dry...but there's a slight amount of condensate in the tail pipes. it doesn't appear to be enough to signal a blown head gasket, though...and the car isn't running bad all the time.

i hate these things sometimes.

 

[projectSHO89]

Moisture in the tailpipe is normal until the exhaust system gets hot enough to evaporate it all. Don't worry about that for now.

It took me a week and a half the first time on my 89. That included 3-4 days of trying to figure out how to remove the corroded-on AC lines and a couple days of walking past the car and kicking it (Hey, I only had 200 bucks in it then).

I did it again last week in about 11 hours, which included a complete replacement of the dashboard shell. I could probably do it again in less than 8 hours depending on those AC lines and how hard they would be to get off.

Go ahead and get the engine hot, then start inspecting. You should be able to locate the leak visually with some patience.

Steve
89

 

[rangerj]

90MTXSHO,

You may want to do a compression test on the cylinders. This should give you an accurate indication of a blown head gasket, or not.

You can also get a test kit from an auto parts store that will tell you if there is exaust gas in the coolant, another indicator of a blown head gasket.

The fact that you are smelling the antifreeze is indicative of a leak, rather than a head gasket problem, but you may want to do the test to rule out the head gasket.

Keep at it and you will find it. rangerj

 

[SW SHO]

Red Raspberry:
If you can smell it while driving it's got to be the heater hoses. Just get some 5/8" and 3/4" bulk hose and a 5/8 x 3/4" adapter.

You can replace all the hoses on you SHO with bulk hose with the exception of E9DZ-8548-B Short "C" shaped hose at oil filter and E9DZ-8548-FA 2 1/2 long X 2 inch ID Behind the T-stat (to the right).

A lot cheaper than the manufactured ones.

Not really. I had one of the coolant lines going to the TB cracked and when I rev'd the engin it sprayed cooland down toward the tranny case. It took taking off every TB hose to locate the small cracked hose (right next to the hose clamp). I could certainly smell coolant while in the car, while driving.

So to say "if you can smell it while driving must be the heater hose" that is true, but not the only way it could happen.