Help finding coolant leak?

[Dono]

Ok, I have had this issue on my 2000 ohv also. Sucking coolant forever. My lower intake manifold gaskets were to blame.
The Symptom was exactly as you explained. Always sucking coolant at a slow rate, and no visible effects of it anywere. I didn't see milky oil, no whitish sludge on the oil cap, nothing.

Then my ex started leaking oil. The oil leak was a valve cover. I did the lower intake and valve cover gaskets(had to, only way to change the valve cover gaskets). When I pulled the lower intake I could see where the coolant was being sucked in to the motor.

The gaskets a *****. Now I have very slight coolant seep on the outside of the motor. A few drops on the garage floor every now and again. No big deal. Cooland resevoir now stays where its suposed to be. There are many threads on this. Apparently the ford gaskets are not the best(They are the one piece gasket). Thats what I used. If I decide to try again, I'll use the 3 piect gasket.

My moneys on that lower intake gasket.

 

[J.J. BIGGS]

Apperently I have no idea what I am Talking About according to these guys. I do agree do A pressure test but let me know when you find out it DEFF is not your head let me know I might know a little about what I am Talking about. By The Way it is prob in a weird area like the one guy said Thats why I sugested to use baby powder It shows the leak every time. JJ

 

[Knox5.0]

Apperently I have no idea what I am Talking About according to these guys. I do agree do A pressure test but let me know when you find out it DEFF is not your head let me know I might know a little about what I am Talking about. By The Way it is prob in a weird area like the one guy said Thats why I sugested to use baby powder It shows the leak every time. JJ

I think someone suggested not to use the baby powder because it could stick to other fluids that may be leaking on the outside of the engine giving the original poster a false result. He would be better off using the UV dye or a pressure test to locate a coolant leak.

I wouldnt be so offended by the other posters comments towards you. You havent actually seen the car in person and it is a little bold to tell a complete stranger that you 100% know that their head and head gasket is not leaking. Its like a doctor diagnosing a patient over the phone. Chances are that his head and head gasket are fine but i think what the other posters were trying to say is if you're wrong in your diagnosis then your opinion could possibly end up costing the original poster a good deal of money.

 

[Dono]

I think we chased Lazzman away.

I wonder how he is making out with his coolant loss issue.

 

[syn-]

if you run the truck and then park it, pop the hood see if you have bubbling in the reservoir and if you see bubbling then you have bad head gaskets or cracked heads. Just went through this on my 2nd motor.

 

[Cobraguy]

Hey man I read all the messages and WOW dont listen to anything that you have read so far I am as close to a cooling system expert as you can get with out a CERT I have had seen this problem in different makes and models. if you have no idea where the leak is doesnt mean its not there I can guarantee its not your head or gasket. If your engine isnt leaking any oil your best bet is to put baby powder all over the engineyou will see the leak then take an air hose and blow off the powder it will all come off except the for the wet Powder And There Is your leak its gone be near the end of a hose Let me know JJ BIGGS

My God. Expert??? Wow. Don't listen to any of the other suggestions? Amazing.

All suggestions are welcome...even that one of yours. But really dude...

 

[Lazzman]

I am thinking it is the heater core, because the coolant stays exactly where it should when I do not use the heater. First noticed this occurence when I started making 100mi round trips on the highway several days a week and I used the heater at those times. Recently it has been warm around here and I have not used the heater on the highway trips, surprisingly the coolant in the resevoir has been staying at the same level??

Going to have to go in for a closer look. With 200k mi on the clock and all original it could be a lot of things.

I'm thinking I should change my hoses soon

 

[Cobraguy]

ALL hoses!!

If the core is leaking, you really should be able to smell it. Also, it should fog the inside of your windshield when on defrost. It's possible it's leaking at the core on the firewall at the hose connection and running down the firewall...but you would see a puddle, or at least some sign of it burning off the exhaust if it's hitting there. Also, the carpet should be damp on the passenger footwell if the core is leaking. But by turning the heater off and having it stop using coolant is a very good indication of where your problem is. Good diagnosis so far!

 

[Lazzman]

Yes, all the hoses. I guess it would be prudent to replace them. Is there any one or two in particular that are more important than the others or wear faster?

I do not have any of the symptoms of the heater core issues you describe, but will go in for a closer look. No sweet smelling anti-freeze no puddles on carpet and no fogging on window. I want to dye the system and them check it out.

 

[iwannabamedic]

if it is the heater core would the windshield fog up more and more?, my old 88 f150 did that really bad a night after replacing the fogging stopped.
My $.02

 

[Lazzman]

No fogging on the windows.

Going to dye the cooling system next and check it.

I have not used the heater in about a week and the coolant level has stayed the same so far.

 

[budwich]

Its likely the "standard leaky control valve, disappearing coolant on the hot manifold" problem but the dye certainly won't hurt.

 

[Lazzman]

Is the control valve the same as the Thermostat? If not where is the control valve located so I can inspect it?

Thanks

 

[96eb96]

Is the control valve the same as the Thermostat? If not where is the control valve located so I can inspect it?

Thanks

Nothing to do with the thermostat.
follow the hoses coming out of the heater core. It is about 1' away from the firewall. It has a vacuum line attached to it.

 

[Lazzman]

Thanks for the update 96, I will check this out tomorrow.

 

[48prerunner]

Did you ever find the leak? having the same type of problem

 

[Alaskanredneck]

Mine was leaking coolant at about the same rate i have been looking for a week just found it today it had to be running when i checked it, and sure enough drip..............drip.................drip ect...

 

[Lazzman]

Have not found the leak yet, but I am suspecting it could be the lower thermostat housing.

I can smell coolant after a decent ride but never see it on the ground, seems to be leaking down from somewhere, quite a lot of coolant residue in the area of the right cylinder head gasket, but I am hoping that it is leaking down from the thermostat housing.

Plan to replace lower thermostat housing soon.

 

[48prerunner]

mine has 198k only looses about a pint or so . Did steel seel in it a year or so ago cause thought maybe a head gasket really only use it on bad days in the winter and once aweek in the summer just to run it. does seem to be a little damp where the two halves of the thermostat housing go together but i put a new o ring in there when i changed the antifreeze out last year.

 

[pifordparts]

Could be anything, but I know for a fact that the thermostat housing on the manifold is a fast selling part on this model. Not only by working for a Ford parts outfit, but by personal experience. I have a 98 4.0 sohc that had the same characteristics, including what looked like a leak out of the right side head. I could also see what appeared to be another leak just above the crank sensor. I did a pressure test, and the leak revealed itself. The vehicle does not create enough pressure at idle, so a pressure test is crucial. If it is the problem, you will see it. Mine leaked to the rear of the t-stat housing, filled the valley, and then to the ground, sounded like it was raining. Anyways, it is a fairly expensive part, about $300 at the dealer. Comes with all new sensors and a new thermostat. Hope it is it, still easier than a head gasket.