Coolant leaked, flush with tap water

[Jay11]

99 4.0 4x4 83k miles.
Sat for 4ish years. Needs fluids flushed.

Before I could get to this truck leaked coolant in about 3 weeks of driving. It has a visible fresh leak streak around water pump. To diagnose it and be sure, I want to flush with vinegar and tap water, then drive it about 10 miles/day for about 3 days. I will flush tap water out with distilled water then add coolant. If I leave this mixture in it for 3 days only will tap water affect engine in those 3 days?

 

[RonD]

That will be fine.

Reason distilled water is recommended is because tap water is not the same every where, distilled water is

"Hard" water has minerals in it, minerals are salts, and of course, salt and metal with a liquid, will corrode/rust the metal, like it does on a vehicles body and frame

Distilled water doesn't have minerals, so no chance of salts
Bottled water often has minerals added, lol, just FYI, so NOT the same as distilled water

But for 3 days or even a month you will be fine
But coolant also has water pump lube/oil in it, so long term you would need to add that, it is sold separately, or put coolant back in

Flush the heater core with a garden hose, in BOTH directions, that will help get a few more years out of it, do this before adding the vinegar and tap water that will allow vinegar access to any build up in the core

 

[Jay11]

Ok so added vinegar, took less than half a quart and rad was full. Added tap water in to reservoir and 2 quarts of oil over filled it. I should have done 1 to 1.5qts.

I turned heat on to max and immediately after starting I noticed oil needle was jumpy but just a bit, here and there. After 8 minutes of idling needle was settled ans steady, temp gauge was a hair Or two off middle. Noticed bubbles in coolant resrv. about 2 to 3 sec., for 4/5 minutes, then an over burst followed, then back to 2 to 3 bubbles per sec, then they disappeared by about 15 minutes of idling.

Where I thought coolant was leaking from I didn't see any leaks.

About 7 days ago it threw a "check gage" light, drove 5 miles home. Next day I did 10 miles, check gage disappeared and I got a CEL. Codes were
P0174 current fault and
P0171 pending fault.
It's been parked since until today. I didn't drive it but just let it idle for15 or 20 minutes.

From all that what would you say is concerning and where should I focus on fixes?

 

[RonD]

"Check gauge"
So which gauge was out of range?
oil
temp
fuel
volts

Or do you mean Check engine light(CEL)?

If engine was sitting for 4 years then fuel system needs cleaning, for now run a can of Seafoam or similar injector cleaner in the gas tank
P0171/174 means the computer is having to open the fuel injectors longer than it calculated for the engine RPMs
This could be because injectors are dirty and not allowing enough fuel to flow out when they are open
Could also be clogged up fuel filter or in tank filter(sock)

 

[Jay11]

Not CEL but check gage light.
The day it popped up iirc it was oil gauge that was a little jumpy, through all this time temp gauge had been steady at half.

The next day it didn't pop up and instead I got a CEL.

When I bought the truck Torque showed no faults other than 3 not ready. I figured must be the old .

In a couple of days I drove the truck to low then I added about 10bux. Drove to nearly empty, then filed the tank. By this time Torque was all clear. Drove truck for 3 weeks, checked Torque on Wednesday-still all systems were ready. Next day check gage happened, drove 10 miles total commute. Next day check gage disappeared and CEL popped up.

I have a can of Techron complete system fuel cleaner, will that do or Seaform is better?

This morning oil gauge didn't go up after cranking. Let it idle for 20 seconds, still didn't go up. I turned it off and didn't drive it. Never seen this before, it always pops up.

 

[RonD]

Change oil switch on engine
4.0l OHV is on the drivers side of block toward the front, has a stand off fitting and one wire

Ford uses an oil pressure switch, so ON/OFF, not actual pressure
Switch is un-grounded with 5psi pressure or less, 0 on the gauge
5psi or higher switch is grounded and gauge shows in "normal" range

These do fail and you get a jumpy gauge and then no gauge
If you didn't hear lifters tapping then oil pressure was/is fine
Lifters start to make noise at about 4psi and under

Do NOT use tape on lower threads of these senders, when installing them, they need a good Ground to the engine block to work


Any fuel system cleaner is fine to use

 

[Jay11]

Thanx. Lifters are quiet. I will order a replacement.

You asked ...

"Check gauge"
So which gauge was out of range?
oil
temp
fuel
volts

For future reference what is the situation for each case?

 

[RonD]

temp would be over heating, usually if it gets to 3/4 on gauge
Fuel is low, usually under 2 gallons left
Volts would be low(under 13 engine running) or high volts(over 15volts) and usually battery light would be on as well

 

[Jay11]

Since I am gonna be in this vicinity & there's no telling how old cureent tstat is, should be a good PM item. But I see temps from 180 to 198. Not sure which tsat is right temp to get.

Have read in Jeep forum to drill a small hole in vertically installed tstat if it didn't have a jiggle valve. Yay or nay?
These don't have a jiggle valves. So are they ok? Should I drill an 1/8th of a hole?

Stant 45359

Stant 45358

 

[Curious Hound]

I think OEM is around 190degrees. But wait til someone confirms. I usually drill the little hole. I think it helps bleed air out of the system.

 

[RonD]

Between 192 to 195degF would be correct thermostat, so 195 in this case

Yes, drill the hole, and mount it so hole is at 12:00, the top

Jiggle valve/hole is there to let any air out that may be trapped behind thermostat at the top of the engine, when refilling or just in general if you have a leak in the system, and air gets in

The jiggle valve has a small rod that will "jiggle",lol, to keep the hole clear of debris over time, just a hole can get clogged up.
This is not "that big of a deal" but since you will be refilling the system and drilling a hole is free, why not
Not a big hole, 1/8" bit is fine

I remove 1 heater hose at the firewall when refilling, then when coolant starts to come out I put hose back on
This lets the air out of the engine side of the cooling system faster

 

[Jay11]

Thanx again.
When I press upper hose it feels like it has a metallic lining inside that gets crashed with every squeeze. I know it's pro'ly lined with crappy deposit and needs replaced. Are these all the hoses I need, because I see a myriad of them and these are the closest I can fathom.

 

[Jay11]

Disregard

 

[Jay11]

I remove 1 heater hose at the firewall when refilling, then when coolant starts to come out I put hose back on
This lets the air out of the engine side of the cooling system faster

BTW which is inlet and outlet to heater core-1 or 2 below?

 

[Curious Hound]

It will be whichever hose comes from the water pump outlet (close to thermostat).

It is actually a good practice to reverse the flow through the heater core periodically to keep it flushed out. You just swap the two hoses right there where your arrows are pointing.