new coolant leak - help ID source please!

I'm going to photobucket.com after poting this, so please check the pics out later...

The Rodeo has turned into my daughter's school vehicle. I found coolant on the ground on the passenger side for a couple of days in a row and I checked under the hood to find the reservoir below low. I have super powers and I am the only one in my house who can see coolant. It seems the leak is coming from somewhere between the alternator and the block. The AT coolant lines are dry. The coolant is dripping from the front passenger side of the oil pan, near the metal lines which go to the oil filter. Could a leak from the water pump show up here?

Pics coming. Thanks for any guesses!

http://img.photobucket.com/albums/v380/surferfletch/leak.jpg

I know its blurry, but this was taken on my back by the passenger wheel, looking up and toward the front and middle of the vehicle.

I think the most common source of coolant leaks on the 3.2 is the piping behind the cylinder heads, between the back of the engine and the firewall :banghead: . There are gaskets or O-rings in there that leak over time, especially if they get disturbed somehow. Coolant leaks under the common chamber, over the top of the block and then trickles down where ever it can. I think you have to yank the upper intake/ common chamber to get at it. The 3.2/3.5 have kinda strange 'external' coolant plumbing.
G/luck
Joel

Additional info:
146,600 miles. Timing belt and water pump last done at 61K. Major coolant hoses are dry. Radiator dry. Original radiator.

It's a steady drip with the engine running. It slows and eventually stops when the engine is turned off.

Thanks again!

Thanks for your reply Joel. I didn't notice you got in before I posted the pic. There is some coolant farther back, but I thought it might be coming from the front and traveling along the top edge of the oil pan as the truck is parked on a slight incline. I'm heading out now to check back there, but the steady drip is coming off the front corner of the pan down onto the center link, then to the ground.

EDIT: There is a line of coolant along the front lip of the pan. I'm heading out to start it and see if I can see it running out of the weep hole in the water pump. The back of the engine looks dry...

I can't see the weep hole from the bottom (EDIT: because the water pump is spun by the timing belt and is under the timing belt covers!). When I first start it, there is no leak. Then, just as it reaches operating temp, it starts leaking. As it runs for a couple more minutes, the dripping stops. I'm thinking water pump.

Is there coolant running through an oil cooler at the top of the oil filter, or do those lines contain oil only?

"Is there coolant running through an oil cooler at the top of the oil filter, or do those lines contain oil only?"
Yep, these is coolant running through an oil cooler, actually it is oil-to-coolant heat exchanger.

Thanks! It may be leaking from one of those lines...

Gonna tear it all down tomorrow. Water pump, t-stat, valve cover gaskets, spark plug tubes, timing belt, tensioner. I'll get it all taken care of at once!

Let us know where the leak is.

Yeah....sounds like maybe a leak at one of the oil cooler lines to me.

Let us know where the leak is.

Will do.

Not the water pump or oil cooler lines or AT cooling lines. I have coolant sitting at the top of the block between the heads. As Joel said, there is some pretty funky routing of the coolant lines up there. I'm going to look around some more with it cold before starting it and looking for leaks when it's warm...

Could be the metal tube at the back of the t-stat housing where it enters the engine? Intake manifold gaskets? Looks like I won't have everything I'll need from the start...

I got all the parts. Does the large coolant pipe that sits under the intake manifold and on top of the engine between the valve covers ever leak? I'm thinking this could be a culprit. I think this is the spot Joel is talking about. It connects to the water manifold at the back of the engine with an o-ring. I'm doing a little reading before diving in....

fletch, that's the area I'm thinking it is. There are O rings back there. Can't seem to find the old posts that were floating around on it. IIRC- they were from 2eyefishclaw quite a while ago.

G/luck
Joel

Thanks. I went down to the parts store, but they don't have the specific o-rings for the water pipe and manifold union. I'm wondering if I can fly with generic o-rings of the same size. I wonder where he got his...

I'm about 2 hours into it. This is going to be one of those weekends where the Rodeo and I spend some quality time together!

1994 Passport aficionado's BEWARE-It could be the o_rings BUT and I Stress BUT before you start dismantling the Manifolds, Think LOCATION_LOCATION, meaning if it is leaking from between the oil pan and the A/C housing or Between the Alternator housing and the Oil Pan it can ACTUALLY be the WATER PUMP>>>The WATER PUMP has a weep hole (AT least mine did), and if it is bad, loose, or worn (EVEN IF YOU HAD IT CHANGED OVER A YEAR AGO LIKE I DID), then COOLANT will LEAK from the weep hole--NO MATTER WHAT YOU CHANGE---If the vehicle is in Park on Normal incline it still will leak without running the engine. IT WILL LEAK just by GRAVITY alone. DON"T SPEND TIME resealing the WATER PUMP with new GASKETS, Just replace the WATER PUMP. It is only a $70.00 Part and it comes with a gasket with it already. Maker sure you use RTV silicon on both sides of the gasket. It will save you a load of time.

>>>>>>Second The COOLANT PIPE that runs through the MANIFOLD--it runs to the rear of the engine as you face your vehicle, from the direction of the radiator towards the engine compartment wall. It is connected to radiator with LARGE BORE HOSE on the TOP Drivers side radiator connection. It then runs beside the thermostat housing under and through the Intake Plenum-manifold,and connects in rear of main manifold, at a T connection on the lower manifold. A LEAK can spring from there and will probably flow to the rear and end up leaking by the transmission housing and mucking everything on top of the engine. IF the LEAK is at the front by the A/C or ALT housing and oil pan seriously consider changing the WATER PUMP. AGAIN, So replacing the O-Rings MAY NOT be necessary-if your LEAK LOCATION is the FRONT. Then consider changing the WATER PUMP but if it is in the back then Consider the O-RINGS, repair at your discretion.

>>>>>>>>>>>>>>>THIRD there are SMALL VACUUM HOSES 3/8 inch in Diameter that are attached to that grey COOLANT PIPE that runs besides the THERMOSTAT HOUSING down-under and just BEFORE it Runs in through the Manifold LOOK for a 3/8 hose that T's off that COOLANT PIPE -and connects to your air intake device--that might be cause for coolant to pool on top of the MANIFOLD. IF it is then just change that hose-a foot of 3/8 hose costs about a dollar, and you will be in business again. OTHERWISE Good Luck!

HINDAO - thanks for the suggestions, but you do realize this thread is 4yrs old?

Wow. Nasty flashback!

Wow. Nasty flashback!

Didn't mean it to sound nasty :eek: Sorry if I did :uhoh:

Naw. I had a flashback! Took me forever and a shop visit to get my leak fixed.

That's right....I remember now....