Where Do I Start? (overheating)

[86hatch5.0]

Alright so I know there are probably overheating threads all over but I couldn’t find much about this so...

I have an 86 5.0 5 speed, that is getting hot some times.. sometimes it runs within normal ranges and others it’s pegged over. The heat also works some times and sometimes doesn’t. It’s been consuming coolant but I don’t know if it’s leaking or from where due to Washington rainy season being in full swing.

As far as I understand it could be thermostat, water pump, or head gasket... or something else.

Any and all assistance is greatly appreciated.

 

[jrichker]

Since finding coolant leaks is mainly a visual process, the first step is to thoroughly clean the engine and engine compartment. Next, clean the area where the car is parked. The position of the puddle under the car will tell you where to start looking for the leak. Start looing under the engine at the front of the engine and work your way to the rear of the engine.

Next is the easy part; sit down and look at some YouTube videos to get some ideas of where to start looking. See https://www.youtube.com/results?search_query=find+coolant+leaks

 

[2000xp8]

You have to find the leak first.
Goto the autoparts store and see if you can rent/borrow the pressurizing tool.
Many times just adding pressure to the system exploits the leak.

It very well may be in your heater core too. That leaks on the passenger side firewall outside or inside the car.

It's important to find out asap that the coolant is outside the engine and not being ingested by it. Water in oil is about as bad as it gets.

 

[Noobz347]

Alright so I know there are probably overheating threads all over but I couldn’t find much about this so...

I have an 86 5.0 5 speed, that is getting hot some times.. sometimes it runs within normal ranges and others it’s pegged over. The heat also works some times and sometimes doesn’t. It’s been consuming coolant but I don’t know if it’s leaking or from where due to Washington rainy season being in full swing.

As far as I understand it could be thermostat, water pump, or head gasket... or something else.

Any and all assistance is greatly appreciated.

How long have you owned the car?
How many miles are on it?
What kind of maintenance has been done?

Please provide some good pics of the engine bay so we can get some idea of the shape that it's in.

 

[Mustang5L5]

If you aren't seeing visible signs of a leak, I'd suspect a leaking into one of the cylinders or Intake gasket potentially slipped. Have you changed intake manifolds recently?

Pull your plugs. Do any look realativeky clean compared to the others?

You can perform a compression test on the cylinders as well as pressure test the cooling system.

 

[86hatch5.0]

How long have you owned the car?
How many miles are on it?
What kind of maintenance has been done?

Please provide some good pics of the engine bay so we can get some idea of the shape that it's in.

I have owned the car less than a week, I got it as a project and as something to restore because it was my dream car growing up. It has 136,000 miles on it and I have no other information than that, I put a sheet of cardboard underneath it and found no spots but there was a piece of foam in the upper radiator hose connection and I also attempted to get all the air out of the system and then drove it for about an hour with no overheating issues.

 

[86hatch5.0]

If you aren't seeing visible signs of a leak, I'd suspect a leaking into one of the cylinders or Intake gasket potentially slipped. Have you changed intake manifolds recently?

Pull your plugs. Do any look realativeky clean compared to the others?

You can perform a compression test on the cylinders as well as pressure test the cooling system.

I have not done any work as of now, I am off tomorrow so I will pull the plugs and see. Can I do the the cooling system pressure test hot or cold? And then I will see about conducting the compression test this week.


Thanks for the ideas and help!

 

[86hatch5.0]

You have to find the leak first.
Goto the autoparts store and see if you can rent/borrow the pressurizing tool.
Many times just adding pressure to the system exploits the leak.

It very well may be in your heater core too. That leaks on the passenger side firewall outside or inside the car.

It's important to find out asap that the coolant is outside the engine and not being ingested by it. Water in oil is about as bad as it gets.

I have been checking the oil to see but no signs just smells a little like fuel, but not milky or off colored.

I have no moisture in the carpet or anything that I can find, and no sign of a leak on the cardboard under the car.

 

[Noobz347]

I have owned the car less than a week, I got it as a project and as something to restore because it was my dream car growing up. It has 136,000 miles on it and I have no other information than that, I put a sheet of cardboard underneath it and found no spots but there was a piece of foam in the upper radiator hose connection and I also attempted to get all the air out of the system and then drove it for about an hour with no overheating issues.

It sounds like you will require the following:

A Ford Mustang Shop Manual and/or Chilton/Haynes and this forum
A complete master gasket set
A complete tune-up kit to include plugs, TPS, wires, cap, rotor, PCV, fuel filter, and a hand full of fuses and several cans of carb cleaner... you may also need a fuel pump and regulator. This would also be a good time to get a couple cans of seafoam, an oil filter, and oil. Don't forget the transmission and differential lubricants.
A good set of hand tools including torque wrenches, a trouble light, and multi-meter, and of course... an OBD1 code reader from Amazon

A new water pump and new hoses would be good insurance as well. You might also check the condition of your vacuum lines and other rubber pieces and plan on swapping them out as you find worn ones. Replace anything that's questionable.

Once you've had a chance to pull codes, we help to figure out what else might be needed.

 

[billison]

Incase no one said it, check for factory pulleys. I had a similar issue on my car only to find a underdirve crank pulley . Swapped it and fixed

 

[86hatch5.0]

Well I had my mechanic look over the car and my water pump was going bad and one of the head gaskets was blown so I went and purchased a Focus ST.

 

[Mustang5L5]

Well that would do it.

 

[General karthief]

That focus will not fit under your hood, I'd fix the head gasket and water pump.

 

[86hatch5.0]

Lol yeah, I’m going to look for a 90’s Fox roller and slowly build instead of always rebuilding someone else’s mistakes

 

[General karthief]

You give up too easy.
What are you going to do with 86?

 

[mikestang63]

disposahle cars
what a concept

 

[jrichker]

Any takers for bets on him showing up next year with similar problems and no ambition to fix them?

 

[Noobz347]

It probably needs a gasket set, tune-up, and pumps.

 

[General karthief]

Lol yeah, I’m going to look for a 90’s Fox roller and slowly build instead of always rebuilding someone else’s mistakes

I've always enjoyed rebuilding my mistakes.

Any takers for bets on him showing up next year with similar problems and no ambition to fix them?

Nah, he's gonna just love that focus and forget all about mustangs.

 

[86hatch5.0]

I traded it in for what I paid for it and got the focus so I don’t have to stress about what I’m going to drive my 7 month pregnant wife around in being that it was intended to be my daily.

So now I’m looking at something that isn’t going to kill my account sitting in my garage while I piece it together. So if there’s a 90’s notch roller sitting around I’ll be about it.