All right guys, I'm having a problem and can't seem to figure it out. For the last three months while driving my truck, at any random moment I get a strong odor of antifreeze inside the cab of my truck. First thing I have done was to put my pressure tester on and check for a leak. Unfortunately, the gauge registers a very slow leak but there is no sign of a leak. I have check, checked and rechecked all my hoses, heater core (being I replaced it recently), water pump, radiator etc. I cannot find a leak whatsoever. Usually when I hook up my pressure tester if there is a leak it shows itself....I know the system is rated for 16 pounds, but even when pressurized to 25 pounds...no leak is presented except for the confirmation on the gauge. There is no odor coming from the vents whether the blower is on or off so I know that rules out the heater core, but I cannot locate the problem. After three months I have checked the coolant and I have lost a 1/4 gallon of anifreeze. Exhaust never smokes other than the black fuel smoke which has always been there, but does anybody have any kind of clue what is going on?

 

Ever get more fog on the windshield when you first turn the defroster on?

With a strong smell in the cab, I am going to bet you have a leak in the heater core.
It could be the hoses to the heater core leaking under the hose clamps, dripping down on the core causing the smell.

Another place to look after the hoses, in the intake manifold webs, toward the heads on both sides.
Coolant there can drop down on the exhaust manifold, strong smell.

 

yea my heater core went and it turned my defroster into a fog machine.

 

It only takes a couple drops to make a very strong smell if the heater core is hot.

Likewise it only takes a couple drops on the exhaust manifold to make a very strong smell.

 

im positive its not the heater core....no fog, also remember, I just replaced it...when i converted to serpentine belt i replaced the heater hoses so its not seeping there either....what do you mean the inake "webbing"? as stated earlier even with the system pressurized to 25lbs there is no visible leak.

 

dave? are you there?

 

Hello??????????

 

am I just talking to myself here?

 

Another place to look is the back corners of the heads. Mine started leaking there and they would only do it when the motor itself was warm it would hold pressure cold but once the head and block warmed up it started a drip on to the exhaust manifold and down to the starter. That ment head gaskets and head studs for me.

 

thank you that is one place i haven't checked.....do you know what dave was talking about with the webbing?

 

Re-tighten the Heater Hoses at the core.

 

I'm not positive but when i had mine apart i think the intake has coolant ports that meet with the heads. If i were you id do some checking as soon as you start getting that smell again. mine would be fine for weeks then it would loose coolant all at once. i finally found my leak in a nice like puddles where it was idling at the car wash.

 

Sometimes you might have a leak only when the engine is warm. I would check around the head gaskets myself, especially the two rear-most cylinders. Cleaned the CDR recently? That's an oily smell, but if you don't clean it every other oil change it could bite you in the rear...especailly when you find yourself replacing the head gaskets because that stinking tuna fish can wasn't cleaned. Intake webbing...give me a minute. I'll go take a picture.

 

Mine is doing the same thing. The only time that it leaks coolant is when it is all warmed up. My head gaskets are leaking up by the thermostat. I am trying to decide if or when I should tear into that project.

 

ASAP. If you're leaking a lot of coolant into the cylinders, there's a possibility of hydro-locking a cylinder. The fluid enters the cylinder and will be compressed from the piston...something has to be the weak link....