HI guys i have a 98 f150 4x4 that has some problems and i think they might be very serious. first i smell antifreeze burning under hood cant seem to find a leak anywhere. also truck has no heat ac works great but no heat also found a milky looking substance under oil cap and only on start up it blows out white smoke. to me this sounds very bad. Anybody that has any input i would be thank full also temperature reading inside truck only goes a little way up maybe a little more than a quarter of the way to half way mark were it should sit at when engine is warm. the truck seems to run just fine has plenty of power. i hear a vacuum leak but cant seem to find it thought i would add that into the factors also one code i believe its running lean.

 

Let's see.....

The usual suspect are....

First check the coolant level make sure that up

Pressure test the cooling system for leaks

Check the water pump weep hole and make sure its not wet

Feel the heater core hoses by the firewall if ones cooler than the other than the heater core has an obstruction....

White scum in oil cap can be attributed to short trips also....

Maybe a compression test is order also

Start with the simple stuff and then work your way up.....

 

found a very s,all leak in front of radiator id that would cause it just looks like a wet spot on the metal grill looking part of the radiator. also i am having a hard time finding the heater core hoses their is 4 hoses like that going to fire wall a picture would be great. also coolant level is normal from what i can tell.

 

Here's a thread..... https://www.f150online.com/forums/v8...placement.html

 

check your dipstick...if there is the milky substance on their you would have blown an intake gasket and your leakin antifreeze into your oil...

 

1. Milky Oil is normal (under the cap), -just a bi-product of the weather and driving habits.

2. Vacuum leak is most likely behind the intake, -close to the firewall. The PCV connection in particular.

3. Coolant smell is either coming from the heater core hard line that's attached to the water pump. Take a flashlight and look behind the alternator, on top of the block cavity. Coolant will collect there if the hardline is leaking.

Could also be one of the two heater core hoses back by the firewall. They can leak, only while under pressure, -intermittently. -Making it hard to determine the problem.

 

okay still cannot find a leak but still smelling antifreeze outside car found my two heater core hoses that come out of the firewall they are connected together so i basically makes a circle? what does this mean. why would the previous owner of this truck do this? found no collection of antifreeze behind alternator so leak is not their is it possible for it be the actual radiator leaking and it still have that burning smell to it?

 

Your heater core is disconnected its has a hole in it and the entire dash needs to be ripped apart to replace it. Huge job take all day (at least) to do it.. Those bypassed heater core hoses are likely leaking..

 

Wouldnt hurt to really take an eye to the lower corner of your rad. Both the F150's I have owned developed small leaks in the lower corners, and were very hard to spot. I could smell coolant after a good drive. Never a drop on the ground and the level always stayed good. Eventually found a little wet spot on the bottom lower rad fins... Replaced radiator in my last truck. This one, well.. havent done anything yet.

But, since someone has bypassed your heater core, that means it was probably leaking at one point and they did not want to replace it. Whether or not it could still be leaking since it has been bypassed, I don't know.

 

will it be fine if i just leave it for now with the bypass hoses on it and where would they leak at if they were to leak at i have seen a little wet spot at the corner edge of radiator would that make the smell just thought something that small wouldnt be able to smell so bad.

 

If your smelling it from under the hood, or after you get out smell it through the front grill I would say yes. That is all that mine was on my previous truck. It was not loosing a noticeable amount of coolant but could smell it. I knew I was going to sell the truck and that is a big turn off and question mark for a buyer. So I opted for a new radiator. That may not be all of your problem though, since you have a previous leak at the heater core. Plus your not reaching operating temp, according to your gauge. Might be possible that the thermostat has been removed? Or an air bubble in the system. Maybe it wasnt burped properly when the core was bypassed.

 

why would someone remove the thermostat what would that do just give a false reading. i actually bought a new thermostat but havent put it in yet but ima do it soon. and also how would i fix the bubble in the system.

 

Ive seen it done before with someone having troubles with thermostats or overheating. It takes forever to get up to operating temps and has a hard time staying there. Runs cooler. Not good for it. Not saying they took yours out but, if it is not reaching op temps, it's a possibility. I would still purge the system though. There is a write up around here on the proper procedure. Maybe when someone made the bypass, air got in the system. Typically with air in the system, it can create hot spots and would show signs of over heating. Just depends where the air is.

 

hi guys okay found the leak its the radiator small leak on top and bottom corners. but when i start the truck it blows out white smoke if it has sat for awhile. the engine has been rebuilt could this have anything to do with not cleaning parts well enough when they were reinstalled on engine if so what could it be and is their anything i can do to fix it.

 

When it sits for a while and blows out "white smoke" is it harder to start? You can pick up cheap hydrocarbon test kits at auto parts stores to test your coolant for exhaust gasses. Which would indicate or rule out a head gasket leak. You may also have a leaky injector.. Either cases could cause hydrolock, which is catastrophic failure. So check your coolant with a hydrocarbon test, check for leaky injectors. Wouldnt hurt to pull your plugs and see what they look like. They may indicate what the issue is.