I have a 2000 Ranger 3.0 V6, which, I have been told has a hole in the freeze plug behind the passenger side cylinder head. I took it to a few places and the lowest quote I have gotten is $1200 to replace it due to the amount of labor it would require. My question is how hard would this be to do myself? Can it even be done by someone who has a pretty limited knowledge of engines?

 

Yes, you can do it, might take a bit of time and patience, lol, cost is high because of labor to get to this freeze plug

Problem is that it is a tight squeeze to get back in there and work

Picture here of the oil pressure sender and the freeze plug thats leaking: https://asavage.dyndns.org/ftp/Aeros..._Gauge_06b.jpg

Normally you would use a punch(steel bar) and hit the edge of the freeze plug until it went inside the head(or block) and usually it pivots so the other side comes out and you can then just pull and twist with pliers until it comes out
But if it drops inside thats fine too, won't hurt anything, it doesn't float so will just sit at a low point, and no it can't block flow.
Then you use a new one with a correct size socket and pound it in.
Not engine room to do that for yours

There will be 3 bolt holes on the front and back of each head, there is no left or right head, they are interchangeable, so each has the same bolt holes on the end
Drawing shows the 3 holes around the freeze plug: https://therangerstation.com/tech_li...rque_small.gif

You could make a metal plate that fits those 3 holes and a gasket with RTV(sealant) and bolt it to the back of the head to seal the leak
Or use the metal plate with a short metal block about the size of the freeze plug and tighten the plate using the bolts to push the freeze plug inside the head
Then use rubber expansion plug to replace freeze plug

You can pull off the accessories on the drivers side front of that head, it will be an exact match to passenger side rear of head, to make your metal plate, and also get bolt size for the 3 bolts

Expansion plug looks like this: https://www.therangerstation.com/tec...ead_torque.gif
They come in different sizes and are use to replace freeze plug when you can't install the cheap ones, you tighten the nut and it expands the rubber out to seal the hole

And no, leaving the freeze plug inside the head will not hurt anything



They are called "freeze plugs" but they are actually Core Plugs, these holes in the head and block are there to remove the sand after the "core" has been cast with molten metal, so holes are "core holes" and plugs are core plugs, lol

Years ago they got the name of freeze plugs because they would pop out if you forgot to drain the water from the engine in cold climate, the water would freeze in the engine and push out the plugs, and NO, this never ever saved any engine block(or head) from being cracked by freezing water inside, a myth from the name
Once there was anti-freeze/coolant in use the name never changed back to core plugs