1999 Ford Ranger 3.0 engine and coolant problems any ideas?

[firefighter4co21]

I have a 1999 Ford Ranger with the 3.0 flex fuel engine. I bought this truck with a possible blown head gasket or a cracked head. The owner told me that it would blow antifreeze back out of the overflow tank. I got the truck and the antifreeze was rusty brown. I did some checking and it seems that this was a problem in the 3 liter engines. I was told the water pumps would rust out. I flushed out the radiator and put in a new thermostat. It also had a odd radiator cap on it. I have run the truck with the radiator cap from my other ranger. After I have done this the truck runs fine with maybe a little miss in it. I ran a compression test on it and all were between 95 and 115 psi. Is this acceptable for compression? I am planning to put in a new water pump but want to make sure the motor is not shot before I put the time and money into a new water pump. Any ideas or insight would be appreciated.

 

[BRUTUS_T_HOG]

putting plain water into the cooling system causes severe rust.

compression is low, but what method are you using? you should crank up till 5 puffs of the needle with the throttle at wide open on all cylinders.

with a new radiator cap it doesn't push coolant out? the old cap might have been bad and the previous owner misdiagnosed..

is the water pump leaking?

 

[B3000SE]

I just did a compression check on my 94 3.0 a couple days ago and I had 140-142 with the method above.I am having cooling issues as well....I think BRUTUS_T_HOG has nailed all the right questions,Do you have a check engine light on ? I think the biggest issue to confront first is the compression,a decent 1999 3.0 should have more than 95-115lbs. I would investigate a Blown Head gasket too.

 

[Bigschwerm]

I agree compression is low...i still have 140's on my 1994 with 235k on the clock

 

[stonwins]

Buy a NAPA block tester. I used mine to check for gasket problem, head crack or block crack. The chemical that comes with the tester is blue. Remove some anti-freeze so level is about 2 inches below of the radiator neck. Start the engine and put this tester on top and use the ballon bulb that comes with the tool suck some of the vapor in the radiator. If the chemical turns bright yellow, you have carbon monoxide in the coolant
which means you have a head gasket problem or cracks. A lot of professional diesel mechanics use this tool.