ok as you can read in the title i have an antifreeze leak on my 87 gxl, everytime i park it theres a puddle of antifreeze under the car but no signs of where its coming from. i looked at it last night and found a puddle of antifreeze under the intake manifold. its not the water pump thats new, and its not the thermostat. what can this be from????? im so confused and this is my only car and i drive it everywhere. please help me.

 

Sounds like your running the turbo engine. On the lower intake manifold flange are coolant passages that feed coolant to the turbo coolant lines. These passages are selead with a rubber o-ring that can break and crack over time. You probably won't see the leak until the system is underpressure.

Anyways, the whole intake system must be removed in order to change out the o-rings. Its a good days worth of work. If possible, I would try and take it off in twp pieces, so just unbolt the UIM bolts if possible, take off all intake hoses to turbo and whatnot, take off the injector harness and any vac lines that lead off the intake system to the other parts of the car then remove the top portion. When thats off you'll need to remove the rats nest and LIM and you'll see the coolant passages.

There is a shitload of more work than just that, so I would suggest searching and reading up on how to do it. Or take a look at the factory service manual.

have fun with that...

 

this isnt a turbo motor, but i really appreciatte your input on it. thanks

 

fill the coolant, start the car, rev the engine, and see where it is coming from. i had a similar problem, but there was never any coolant on the ground. i thought i had bad seals, but just turned out to be a bad hose

 

all hoses are good and i did start it and rev it but i couldnt see where its coming from. thank you for replying.

 

If there's a puddle under the intake manifold (sitting on top of the engine block), chances are good that one of the lines going to the throttle body has failed. Fix those lines (or bypass them & remove the cold start unit & readjust the idle), and you should take care of the leak.

-=Russ=-

 

hey thanks a lot man, do i have to take off anything to get at these lines?

 

hey thanks a ton man, i just looked at a couple of the lines and found a little hole in one of them. i cant express how much i sppreciatte this man. thanks again

 

No problem. Guess how I know what a coolant leak on top of the engine block most likely is?

The hoses are some goofy molded shapes, depending on which hose it is. If you can't get a direct replacement locally (unlikely) and can't wait for Mazdatrix or such, you can get a standard L-hose from your local parts store, and bypass the whole setup. You run the nipple on the rear iron to the back of the water pump, bypassing the entire throttle body. If you do this, you'll either have to remove/adjust your thermowax, or live with a 1500 RPM idle until you replace the coolant lines to the throttle body.

-=Russ=-

 

You'll have to pull the upper intake manifold, depending on which line it is. If you still have all your emissions intact, this will be painful - I suggest using masking tape to mark the vacuum lines. There are a LOT. If you've removed the emissions, pulling the UIM off is pretty trivial.

If you haven't done it before, be aware that there are 5 connections between the upper & lower manifolds. There are 4 nuts around the edge, and then a bolt in the center towards the center of the car. You'll need to release a few bolts on the other side (driver's side) as well, and disconnect the throttle cable & cruise control cable (if you have it).

I'd suggest taking pictures of how it goes if this is your first time pulling it apart. If not, enjoy!

I have no emissions stuff left, and I can pull the UIM in about 15 minutes (if I'm not in a hurry).

-=Russ=-