Okay, I'm a shadetree mechanic with no leaves on my tree.

My coolant system on my 99 F150 Triton V8 is leaking water bad.

The water is coming from the left rear area of the engine.
I have removed and examined the Heater Core hoses and Orings and they appear to be fine.
There is no water at the core inlets or inside the passenger side so I know my core is good still, Thank god. (don't want to mess with that one).

I am told there is no Heater Control Valve on the 99 F150?

Inside the Lame Haynes I see that a coolant temperature sending switch is located at the front left side of the intake manifold. ??? All I see are fuel injectors. Do they mean the left rear of the engine perhaps?

I have tried to use a mirror and flashlight to see where the water is coming from but there is absolutely no room for my big hands to navigate the mirror and use the flashlight to see the leak.

When I removed the heater hoses I connected a loopthru (bypass the heater core) just to check and it's still streaming down the back side.

All the water is coming from the left rear side of the engine, the right side is dry. The water is leaking down and over my starter mount and then all over my heat shields and exhaust.

One other note, I can see a little standing water below the intakes when I shine my flashlight between the gaps, the water does not seem to rise when the leak is occuring so this may be blow off when driving??

Any help would be appreciated.

 

Sounds to me like you may have a blown head gasket. Possibly could be a warped head as well. It seems like you checked the most likely(and most easily fixed things) already.

Did you have an overheating problem at some point? Or was there an occasion where it overheated even once? If so then I would suspect a warped head.

Aluminum heads are known for this and as a result have prompted gasket makers to develop gaskets that can deal with the issues of bolting aluminum to iron.

The worst case is you may have a cracked head or block. Make sure though that you have checked every hose, tube and fitting that carries coolant to the back of that block. As you already know this can be tough, but it has to be done.

Hope this helps.

 

Thanks for your response,

The Engine has Never overheated, the gauge shows proper working and gradually increases to 'normal' operating range.

The only problem I have had to date is that I had a small hole in the upper portion of the actual radiator. The other day I started adding water when a bystander pointed out that water was leaking pretty fast.

This is the first time I have noticed any problem with the coolant system minus the radiator itself.

 

UPDATE!!!

For anyone that may ever run across this situation, here's what happened and how we fixed it.

The heater core (inside the dash) has two pipes on the firewall, one inlet and one outlet.

The one hose comes from the water pump into the core and the other goes into a pipe connected to the intake manifold.

The pipe into the manifold is where my water was leaking from. For some reason a small hole was created in the pipe after the hose connection and just above where it connects to the manifold. The hole was on the back side of the pipe where it was very difficult to see even using mirrors and flashlights.

My brother in law happens to be a certified mech. running his own shop and told me to bring the truck to him to have a look, he found the hole in under 3 mins. and came up with a plan to fix.

He took a small 1 1/2" gear clamp and a piece of heater hose and wrapped the heater hose piece around the hole and clamped it down. Wow, no more leak.

I am so grateful this was not a bigger deal and that I have an awesome in law that fixed my truck up and said it was an early christmas gift.

Just wanted to give the update and if this defect ever happens to anyone else hopefully this fix will help you.

 

except i cut the pipe coming from the intake off but about 6 months later a new hole sprung so low i cant cut or patch. so now i thought i would pull the pipe out wrong broke off now this realy sucks any suggestions on getting the broke pipe out of the intake without removing it. thanks for any help.

 

Without ever having the intakes off my truck I couldn't tell you what the pipe looks like at the intake end or how it is secured.

My brother inlaw that made the repair said it was a 'pressed pipe' I guess meaning pressed compression?

If this is the case and again I don't know but from my experiences in the 'real world' could you maybe take a pipe puller? kindda like would be used in lawn sprinkler repair? Home depot sells these cheap and maybe insert the flared end and twist upwards?

I am guessing that if it is a compression joint you could insert something that would grab it cirmetrically and twist it back out.

What I can tell you is that the haynes manuals won't tell you anything other then important torque ratings. They don't seem to dwell in the finer details that keep an engine running.

Let me and us know what you find out and I will try to look it up from my end, as I may be attempting another repair in the future from what you say.

 

i have a weird problem with my 97 4.6 L it leaks water when it is cold, and makes a weird whining sound, then when i barely press the gas, the sound goes away after 10-15 seconds.... after the truck gets warm, there is no more water leak, now i just recently replaced the plugs/wires, and am wondering if i had knocked the heater core hoses loose by a slight possibility.. any help would be appreciated

Jason