I have a 1994 F-150 Ext. Cab 5.0 V8.
I know i'm an idiot for buying a vehicle off of Craigslist and not having it checked out before purchase, but it's my truck and i've inherited the problems.

That being said, i'm trying to figure out what it will cost to replace the entire cooling system. Some of the problems I can do myself. Others, i'll take it to a mechanic.

My everyday use is not affected by the cooling system, but if I try to tow my boat, the temperature gauge skyrockets and the truck overheats.
Firestone has already told me there's junk somewhere in it, but if they do extensive cleansing, there's a possibility that it could cause more problems.
So, I just want to not worry and replace the entire cooling system.

So, i'm thinking the cooling system consists of:
1) Radiator
2) Coolant Reservoir
3) Water Pump
4) Cooling fan. (Which is working.)
5) Thermostat
6) Heater Core
---Am I missing anything?

I'm pretty sure the only things I cannot do myself is the water pump and the heater core.
Does anyone know about how many hours it would take a mechanic to fix those two problems? (So I can calculate the labor cost. I have already researched part prices.)
I'd rather fix the problems than buy a whole new truck.

Thank you for any answers given!!

 

Well, no matter what used vehicle you buy you are getting somebody else's problems. A vehicle from a dealer is just a likely to have as many issues than from a private individual, possibly even more so and you are likely to pay a lot more besides.

On your list of the cooling systems components you may want to include the radiatior hoses and the belt that turns the water pump. Also, the fan itself usually isn't an issue, its the clutch that engages it, and its not that easy to tell if its working or not. Just because it is turning doesn't mean the clutch is working correctly.
Also, I wouldn't go to the expense of replacing the whole cooling system until you know what the problem is.

I would be leery of a garage that just told me there is junk in the cooling system for a couple reasons.

The first one is that its not that hard to figure out where the problem is if the system is actually blocked up somewhere. You can feel if the thermostat is opening by feeling the upper radiator hose. You can shut the truck off after that and tell if the radiator is working by feeling it for cold spots, water pump should circulate water, etc....

The second reason is that cooling systems usually don't magically clog up. I'm not saying it can't happen, but its much more likely somebody put something in the cooling system to cause it to clog up.

There are two common reasons why somebody would put something in there, the first one is because it had/has a water leak.

This could be because of one of the cooling system components we have already talked about, or because a freeze plug or plugs were/are leaking. Some careful observation will generally tell you if this is the case, it may stop the leak, but doesn't eliminate the evidence there was a leak.

The other reason is because of a head gasket/cracked head and/or block. Its pretty common for people to dump a bunch of sealer in a system to cover this up and sell the vehicle. Its also common for them to ThinK it has this problem and dump the sealer in and sell it.

Any half way competent mechanic/garage should know these things and should have told you about them. Not just said, "Got junk in there".

You want to find out for a fact why it is overheating under a load before you replace anything, otherwise you may spend all that time and money and still have exactly the same problem.

You can figure out what is wrong by yourself, but it may involve a fair amount of effort, but very little cost.

You may indeed have a partially clogged radiator, in which case you can flush it out yourself with a garden hose good enough to find out for a fact if it was the problem or not. Just bear in mind there is a reason why it is clogged.
You might have a weak fan clutch, which you can test and replace easily. When the engine is cool the fan should turn fairly easily by hand, but when it is at operating temp turn the engine off and turn it by hand again, it should have considerably more resistance.

I mention these two things as they are common sources of overheating under a load.

Head gaskets are another common reason. You can buy a tester at Napa that is fairly easy to use and will tell you if there are combustion gases present in your cooling system. It costs about $20 and comes with a bottle of liquid that changes color and directions for use.

Personally, if I bought a vehicle off Craigslist and it was overheating under a load I would start by checking the headgasket to make sure I'm not chasing my tail by replacing cooling system components.

edit: If your heater core is the same as my truck I just replaced mine and it was the easiest heater core I've ever done, not sure if they changed the setup when they changed the interior but if they didn't then you can do it yourself. The water pump is another story. They like to break bolts off because of the aluminum on steel oxizidation problem. They can either come apart easily, or be a bear and require removing the timing cover. A good mechanic should know about this, meaning he should tell you about the possibility ahead of time. I personally try to avoid small block ford water pumps, but if I do one I let the customer know what the issue is. If one breaks off and I have to pull the timing cover I charge more.

 

The Heater Core is not going to make it over heat.
If the bottom radiator hose does not have a spring in it this can make it over heat under load.
Some will leave the spring out of the new hose when they change it out and then the hose will collapse under load.

 

I would look for a "heavy duty"or "towing" radiator. No need to replace everything.

 

i agree with bdelmar2. i dont have as much knowledge as him but i know enough to understand. dont go crazy until you spend more time pinpointing things. i definitely agree with his comments about mechanics. theyre mechanics for a reason. they know more than "theres junk in it" lol like i said i dont know enough to give you mechanical advice but be patient with your money until you can figure out the true problem