Hello All,
I have this 2001 Ranger 3.0 U, I bought that supposedly needed a drivers side head, but was torn down to the short block in the truck. Im guessing he quit when he couldnt get the oil pan off in the truck.

So I bought it and took it home. I ran across a used engine & transmission, that the guy said worked fine. He pulled them out to put a 5.0 in. I decided to just pull the remainder of the engine out and put the used engine in.

Got the engine installed, filled up the fluids and fired it up. Turns out, it has a misfire on cylinder 5. The radiator that came with the truck was almost completely stopped up. I put another radiator I had on and ran it and warmed it up. Topped it off like 4 times. So, here is the turnout.....

Cylinder 5 misfire & keeps losing coolant. Coolant not going to crankcase & no evidence of a visible leak. So today, I took a compression test......
1 - 145
2 - 140
3 - 140
4 - 120
5 - 135
6 - 140

So Im not sure why 4 & 5 are lower. Could be a valve or might even be a head gasket failure. However, anything over 90psi should be enough to fire a cylinder. Could it be #5 has a injector problem showing the misfire on the scanner?

When I go back, Im going to pressurize the coolant system to see if Im getting coolant in a cylinder.....or try to find where the coolant is going.

Oh, also tach not working. I think it works when the scanner is plugged in. But normally does not.

Thanks in advance for any help.

 

how much coolant is it loosing? any smoke? could be a head gasket. check here on the forum how to test with a dollar bill or piece of paper.

 

The first time I ran it, it smoked some. Exhaust system could have had moisture in it from previous engine's cracked head. After it warmed up, then no smoke. Ran truck twice, no more than an hour each....lost about 1/2 a radiator each time. I still have the plugs out from the compression test. Going to pressurize coolant system and have a look around with the bore scope.

 

if you dont see it leaking or dripping its going out the tail pipe. does the plug look any different in cyl 5?

 

Just looks like its not firing, and dont really smell like its flooded, but does smell gassy. Thats why Im questioning injector.

#4 plug Im thinking has a slight reddish color. Im thinking red means burning coolant?

 

With both 4&5 low, I am suspect to gasket or crack.

 

these motors are known for burnt valves, that can cause a missfire. the coolant has to go somewhere, on the ground or out the pipe. plugs with a blown head gasket usually much different than the others..

 

Ok. I topped off the coolant level. Pressurized coolant system to 11 lbs.held pressure for 30 mins so far. No leaks visually on the floor. Turned engine over, still have plugs out. No sign of antifreeze blowing out of the cylinders. Going to leave it pressurized till I return. Where the heck could about a gallon of coolant go if it aint going to the crankcase, cylinders or on the floor? 🤔
Stay tuned......

 

Went back by to check on truck. Pressure leaked down 1 pound.in 2 hours. I added back the pound & turned engine over again. No sign of coolant on the floor or in any cylinder. I left it pressurized to see if it leaks any before I get back.

Guess the next thing to do is a cylinder leak down test.

 

I’m guessing you’ll find something out here pretty soon

 

Went by this morning to find coolant system leaked down 2 lbs. 2 small spots of coolant on th floor. Didnt have time to investigate where it was leaking from, but will look when I go back.

Ordered a leak down tester and it came today. Maybe if the weather straightens out next week, I can get cylinder#'s 4 & 5 checked out.

 

how much did it leak? the coolant system might have had an air trap and now its full?

 

I topped it off before I put the pressure tester on it the other day. It leaked 2 spts on the floor about the size of a quarter. 1 spot at right side of radiator the other pass side center of engine.

 

so 1gal? question is how much is it leaking.

 

The gallon was added in 1/2 gallon intervals after initial fill of about 2 1/2 gallons. Added another 1/2 gallon when topped off for pressure test. So that was 1 1/2 added after the initial 2 1/2 gallons.

But pressure test leaking very little. 2 spots quarter size. None in cylinders or crankcase.

 

I googled this. Maybe it’ll make some sense


2001 Ford Ranger with a 3.0L engine requires approximately
14.9 to 15.2 quarts (roughly 3.75 to 3.8 gallons) of coolant for a full system capacity. This includes the capacity for both automatic and manual transmission models, though it is recommended to have extra on hand for the reservoir and, if necessary, to account for spillage.

 

Hmmm. Interesting. Maybe I didnt have it completely full. I am going to investivate the small coolant leaks.

After I do a cylinder leak down test, I am going to remove the engine again. Probably have the heads reworked & do a engine reseal, to fix the mess somebody made with sealing the timing cover. Looks like they used tub and tile sealer or something weird....and alot of it.

I would have done all this before installation, but didnt know if it knocked being a used engine I never heard run.

HopefulIy it wont knock when I get it back together. It has 210k on it and my previous ranger was totalled at 425k...and ran like a sewing machine.

 

A cooling system pressure test overnight and a borescope check for steam-cleaned pistons would confirm that quickly. The misfire could still be injector or wiring related, but coolant loss needs priority. As for the tach, that’s often a cluster or signal issue from the PCM, especially if it works with a scanner connected. Since the engine and trans came from another truck, it’s worth verifying the donor specs and calibration compatibility with a vin checker https://carfast.express/en/cars/check to rule out mismatched components that can affect sensors, injector behavior, and gauge signals.

 

Pressure test revealed outer engine leaks. Going to do a cylinder leakdown test on cyl's 4 & 5. Bore scope did not reveal steam cleaning in either cylinder. Going to install new plugs and check ignition coil & spark thoroughly. If good, then will move on to injectors.

Dont understand tach not working without scanner hooked up.