I have been puzzling over an odd coolant leak for about a week now on a 1994 2.3L manual transmission Ranger, 150,000 miles.

I think there's more than one thing going on, but in any case, when I add water to the radiator, engine off and cold, it drips out rather quickly from between the transmission housing and the engine block.

But after a quart or so, it stops. I can drive for miles with no overheating.

Sometimes I can fill the radiator and it doesn't leak at all.

Backing up: couple of weeks ago I drained the radiator and found oil in the coolant; no indication of water in the oil, though.

So you'd think blown head gasket, but that wouldn't seem to account for the leak from the back of the engine (the water doesn't seem to be coming form the head.)

So maybe a freeze plug if there's one in the back of the block, or a serious crack high on the block AND a head gasket malfunction.

It runs perfectly, no smoke from the tailpipe...took it to the dealer today and was told I would need to leave it for FIVE DAYS just to see what was wrong. I took that to mean they didn't need my business...

Any suggestions from those more knowledgeable than myself (which is just about everybody) would be appreciated...

PS- Truck has a new Bosch water pump, 195 degree thermostat, thermostat housing, and fan belt, and has been flushed twice with Prestone Radiator Flush...very rusty water in there.

Thanks...

 

Turned out to the leak was be a pinhole in the rear freeze plug.. had to use a mirror to see it..

Does anyone know if this can be removed and replaced without lifting the engine? Also, would it make sense to replace all the freeze plugs since they are probably all about as corroded as the one that let go first? (The truck went with too weak a coolant miture for a year or more...)

Thanks

 

It'll probably be a tight squeeze, but if you can get some tools up there you should be able to replace it without pulling the engine.

I'd probably replace them all if you have to pull the engine, otherwise, just replace the one that is leaking. don't forget to use a brass plug instead of steel ones....

 

if you can fit your tools up there, then go for it. if you can access the rest of them, just inspect them. but you know the old saying, If it ain't broke, don't fix it.

 

Thanks for the replies. There 's a little space to work in, so I'm going to get a brass plug and give it a try.

And if I have ever have occasion to pull the engine, I'll do the others.

(My personal version of the old saying is: "If it aint broke, give me a minute.")

I'm probably going to need to pull the head in any case... as I mentioned there was some oil in the coolant a couple of weeks ago -- no coolant in the oil thankfully -- so even though after a radiator flush it hasn't happened again, and the truck continue to run just fine -- I'm sure there a head gasket failure of some sort....

 

Well if you're going to pull the head to replace the head gasket, you should easily have enough room to replace the plugs. Don't forget to sand the seal area and use red loktite to seal them up and keep them in there...

 

yeah, I guess I'm still cllinging to some hope that the oil-in-coolant scenario was a one time event, but I know there really is no other good reason for it occuring. I'm taking the truck this weeknd to a mechanic friend and I'll find out for sure.

(I've already spent $2000 on a vehicle with a KBB value of $600, so why stop now?)

So far:
--new tires
--new shocks
--new water pump
--new starter
--new thermostat
--new thermostat housing
--new upper and lower radiator hoses
--new heater hoses
--new hose clamps
--new windshield
--new windshield wipers
--new taillight lens
--new headlight, taillight, brakelight and signal bulbs
--new front bearings
--new brake pads
--new upper and lower ball joints
--new speakers
--new hub caps
--new sway bar bushings
--new spark plugs
--new spark plug wires
--new fuel filter
--new air filter
--new oil filter
--new serpentine belt
--new timing belt
--new tensioner
--new pulleys
--new headliner
--new fuel sender
--new brake light switch
--new rubber pads for brake, clutch and emergency brake pedals
--new differential fluid
--new transmission fluid
--new power steering fluid
--new brake fluid.

I think I have the value of thing up to at leat 800 bucks at this point.


All of this just to get it ready to give to a friend... kind of ridiculous really.

 

Turns out I had TWO freeze plugs leaks... one from the rear of the cylinder head which I JB welded, and one apparently on the rear of the block which I guess requires pulling the engine. Another $1000 repair for an $800 truck with a $3 part.

 

its a ton easier to pull the tranny and you can do the repair on the freeze plug on the backside of the engine. Shouldn't take more than a few hours to do actually.
Its a weird size plug, so its kind of hard to find it in brass, but i got one from Napa.
Hope that helps.

 

Thanks. I was wondering it dropping the trannmission was an option. Might even be a good opportunity to put in new clutch

I'm taking the truck to a friend's workshop this coming Saturday... he's a GM transmission mechanic so he'd probably be happy to approach things that way.

I'm pretty sure ALL the freeze plug need replacing, so we'll just have to see if they can be reached with the engine in place. I ordered the last 4 Dorman 1.5" brass one that Amazon had in stock...hope they fit....gotta come up with 3 more somewhere

Thanks again for your help...it is great to be able to hear what knowledgeable people think on this little problems we run into...

 

if i where doing this i would just pull the eng. out your already more than 1/2 way there when you pull the head for the headgasket and you stated you where considering pulling the tranny. just go the extra step and pull it out. at least then you could check the lower end and replace any gaskets that may be leaking.

 

You're right ... it's just a matter of what my mechanic friend has time for... he has a lift and the whole nine yards at his home shop, so we'll see.

I'm going to determine once and for all if there's a head gasket failure this Saturday and I suppose we'll take it from there.

Thanks...

 

Oh yeah, if you're pulling the head, it wouldn't be too much work to just pull the engine out and that way you can replace the freeze plugs very easily.
I think you only need 5 small plugs, and 1 big one...don't forget the one on the back of the head!
This is what i had when i did mine on my engine build...

 

Thanks Danger... I was under the impression that there were three on each side of the block, one on the rear of the cylinder head, and the especially troublesome one on the rear of the block, with maybe all but one being 1.5"


And, yeah the one on the back of the head I "fixed" with a washer and some JB weld. That was just temporary, but it's holding well for so far.


Thanks again for your assistance