2.5L ('98-'01) Overfilled coolant then empty

[computersoc]

My 2001 Ranger XLT 2.5L engine with 231k miles had the coolant at the proper fill line in the overflow reservoir. It stayed at the same level for the past 7 years. That's the last time I had the water pump and thermostat replaced.

I noticed the other day the coolant was overfilled in the reservoir on a cold engine. Obviously I didn't add anything. I thought it was odd but left it as is.

Yesterday I was at highway speeds and the truck just shut off for no reason and without warning. I had my foot on the gas and lost power, then all the dash lights went on. It would try to crank and make the noise like a low battery but it wouldn't start. I checked the coolant and it was still around the overfilled level.

I checked the coolant today at the shop I had it towed (they're closed today) and the reservoir was totally empty.

Any idea what this could be?

 

[Dirtman]

Head gasket done blew up.

 

[RonD]

2.5l SOHC Lima engine uses a timing belt, it may have broken, when was it last changed?
No engine damage occurs, but engine will stop running and not start again, and will "sound funny" when trying to start since valves are not opening and closing, so compression builds up in a few cylinders and slows starter down like low battery would


Blown head gasket would be on the table for the overflow tank level being high, but dash temp gauge would also show HOT if that was the issue, and "check gauge light" would have come on well before any engine issues
I wouldn't think the high level and engine stalling would be related with symptoms described
Could just be a failing rad cap, not letting coolant flow back in to the radiator as it cools down

Also blown head gaskets or cracked heads usually can't cause a No Start

As any engine heats up the coolant in it expands in volume, thats where the pressure in cooling system comes from
When pressure exceeds rad cap rating, say 15psi, then the larger valve in rad cap is pushed open and the hot coolant is sent over to overflow tank
After the engine is shut off the system cools down and coolant SHRINKS in volume, so if any coolant was sent over to overflow tank then radiator pressure would go to -1psi, negative pressure, this would cause the smaller valve in rad cap to be PULLED open, and suck coolant back in from overflow tank
Simple system

If there is even a small leak in the engine/rad side or in the overflow hose, then the system can't "suck back in" coolant from the overflow tank, because the outside air is much easier to suck in than coolant, lol

Head gasket issue means pressure from a Cylinder, 900+psi, can flow into cooling system, this would cause rad cap to open and send coolant over to overflow tank, since pressure exceeds rad cap rating
This also pumps "air"(exhaust) into the cooling system and displaces the coolant, this causes engine to over heat fairly quickly
Within 5-10min of driving
And overflow tank would also Bubble as the "air" makes its way to top of rad and is pushed out by the higher pressure

 

[computersoc]

Timing belt was done at 160k which was 7 years ago with the water pump, radiator cap, upper and lower radiator hoses, and thermostat.

Temperature gauge was where it's supposed to be the entire week and when this happened. Plus like you mentioned, no lights came on (until after the vehicle shut off, then all lights came on).

I checked the oil level on the dipstick the other day and it was normal. Looked normal too. I didn't check the oil after this happened.

 

[RonD]

My guess is that timing belt broke
Ford specs 70k miles or 7 years, most Ranger owners go for 100k, lol.
And years are tricky because of climate, hot dry climates shorten life of belts and hoses, and "rubber" parts

If you want to check it have someone crank engine while you look behind timing belt cover at cam gear to see if its turning

 

[computersoc]

It's a blown head gasket. Oil on the dipstick looked like chocolate milk.

Anyone think it's worth throwing a new engine or repairing the head gasket, or is a northern truck with 231k miles basically worthless? Didn't know what used trucks go for versus repairing this.

 

[Dirtman]

If it's mechanically sound otherwise a new headgasket and timing belt is not a hard job and would be worth it in my opinion if you're doing the work yourself. A 2001 2.5 truck with 230,000 miles and a blown head gasket won't be worth much to sell. It's basically either fix the truck or accept scrap value for it...

 

[computersoc]

Can a 4.0 be put in easily?

 

[Dirtman]

No, not easily. You'd need a complete 1998-2000 4.0 ohv or 2001-2003 4.0 ohc 2wd donor truck for parts. You'd need the engine, transmission, computer, complete wiring harness, radiator, PATS system, ignition and keys to match, along with a ton of other stuff. And that's all assuming the engine and transmission from the donor truck are in good condition and don't need any work which is unlikely.

 

[RonD]

+1 ^^^

Never would have guessed head gasket issue without overheating as a symptom

 

[Dirtman]

+1 ^^^

Never would have guessed head gasket issue without overheating as a symptom

Limas are silly like that.

 

[computersoc]

So the 4.0 would be a hassle to swap, what about a 3.0 or 2.3?

Would the engine come with a water pump and radiator or should I buy new ones since it seems there was some overheating issue? I say that based on the coolant looking overfilled the other day on a cold engine and then the coolant being gone today.

 

[Dirtman]

Swapping to any other motor except what you have now (2.5) would be the same hassle as a 4.0, they would all require a new transmission and all the wiring and crap from the donor truck. A 2.3 uses the same transmission but it's working backwards, it's just a smaller less powerful version of the 2.5 you have now.

 

[computersoc]

Sounds good. A few places said engines are around $800 to $1000, but nothing low mileage. All 150k to 200k.

What are your thoughts on a new radiator and water pump?

 

[Roert42]

almost any engine swap, besides the same engine you have in the truck, to make it as easy as possible you would want a complete donor truck( usually something that runs well but is super rusted or has a bent frame).

Easiest thing would to get a 2.5 from a junk yard, clean it up, and put that in.