Hey guys! I've searched these forum and couldn't find anything similar to what problem I've been having so here goes. The other day I replaced my passenger side cam (o-ring) seal and saved money by not having it service by a shop. I've been pretty careful not bumping in anything or damaging anything around that area after which I did an oil change as well. With my montero on jack stands, I started the engine to circulate the new oil and test my oil level. That is when my problem started, I noticed coolant dripping right under where the transmission pan is. The coolant is dripping on both sides but is coming from above the transmission itself, the coolant is leaking somewhere above that area then it drips to where the transmission pan is. Looking from above the engine, I can see from a gap on the driver side to where the top of the tansmission is, there is a little puddle of coolant there but I can't exactly trace as to where this leaking is originating from. I also used an extendable mechanic's mirror to see that leak from above the transmission but it is not coming from above it either. I'm really stumped as to where this leak is coming from and it is pretty big. with the engine running for a minute I am losing at least a cup of coolant. Even If I want to take my montero to a shop I can't drive it because I'm worried it would get worse as it is. If someone can give me any advice I would greatly appreciate it.

 

Are you over heating? Sounds like it could be a head gasket. Was the oil tan and foamy? The easiest way to detect a blown head gasket is typically water in the oil or vice versa.

 

Another source of leaking from up top could be where the two coolant hoses join the back of the throttle body. You might also check these out.

 

So far it is not overheating, and there is no indication that I have blown a head gasket and oil is mixing in it. The coolant coming out is clear and it does seem to be coming out from somewhere behind the engine. From there it drips to the transmission on top and then slides down on both sides where the transmission pan is. I'm gonna check the two coolant hoses behind the throttle body that you mentioned. I'm gonna start troubleshooting it again. Thanks for the advice guys and I'll give you guys an update!

 

Update: I just took off the whole top intake manifold and was able to see behind {close to the firewall} the engine where the two coolant hoses are, they are dry and no leaks. Tried to feel behind the whole back side and just realized the coolant dripping to the transmission was coming from the middle part of the engine {right between the V area}. Used my flashlight and peek right between and under the rest of the manifold and fuel rail and saw coolant nestled between the banks of the engine....I think I'm screwed, this looks like bigger problem than I thought. Can someone help me describe what is under the rest of the intake manifold and is there a coolant line under there? I'm gonna continue disassembling the rest of the manifold and possibly the fuel rail also so I can get a better look at the damage. I don't see any hoses between that area so I'm kind of worried now it might be some cracked metal where the leak is coming from. Could it just be some gasket that broke? there is still no coolant mixing with the engine oil so it still isn't a head gasket. Gonna update again once I get those parts removed....

 

jer01mont ~

Glad you checked the easy things first; no harm in that. It is possible to have a head gasket leak without it going into the crankcase oil. Rare, but it could happen if the leak vented outside the head without encountering an oil gallery along the way. Since you're playing Digger Squirrel and taking things apart, keep doing so since it seems like that will lead you to the likely source of your headaches. At least we know it's gotta be coming from somewhere! Let's just hope it's something like a blown gasket and not the dreaded cracked bloc... I'm not gonna even say it.

I can't think of any surprises you might encounter along the way. Under the plenum is the fuel rail and the inlet manifold. I guess it's possible if you were the lucky sort that it could be coming from around the thermostat housing and flowing back to where you're seeing it, but I would have thought you'd notice something so obvious (and inexpensive) as that by now.

Keep digging, Squirrel, and let us know what nuts you uncover.

 

2nd Update: Finally was able to finish removing the whole intake manifold down to the block. You can tell from the pics that the whole valley between the engine block is flooded with coolant. All the gaskets are good so the final step for me I guess is removing that middle pipe running down in the middle and see if the O-ring is busted. That's my final guess because I've pretty much taken it apart. I will also remove the timing belt cover and do a water pump and timing belt replacement. I've never done a belt replacement on a V6 before, but my guess is I have to replace water pump as well just to be on the safe side and see if there are broken seals in that area as well. Any advice as to whether I need any special tools for this any technique I might need so as not to mess up the timing? This has become more work than I expected and I admit I'm way above my head in this one. You are right mothman52, It is the only area left where coolant could leak from so I'm going to take that apart next. Again guys I appreciate all the advice you have provided so far and I'm learning a lot. Thanks I will update again soon!

 

eather the pipe has a hole or it is leaking from the "by pass" pipe seal by the thermostat...

 

Jer01mont ~

Congrats on going ahead with your tear-down. I'm certain there are a lot of members who are going along for the ride, learning along with you. You're not in over your head — you're a trailblazer Sounds better, doesn't it?

And it's absolutely genius to post pics. Again, smart thing to do; it can only help your cause. Speaking of which, it looks to me like it's damp above the puddle in the first picture, like the fluid is coming from your head gasket and leaking down into the puddle. Is that how it looks to you in person, or is that just a shadow or a smudge of some sort? Because that would certainly explain things.

There's a timing belt sticky at the top of the Montero threads. Check it out. If you've done this before you should be familiar with the basics, making certain that the TDC isn't screwed up and that all the marks align. Check back in when you get to that part for more specific information.

http://www.pajero4x4.ru/piii/GR00003800-11B.pdf

And finally, remember: there's nothing like learning by necessity!

 

3rd Update: Thanks Mothman52! for the advice you've given me and that link was a lifesaver because I don't have a service manual and this really really is a big help. Since taking apart the intake manifold down to the thermostat housing, I really can't start the engine and re-create the leak, but looking at the gaskets from the thermostat side they are a bit worn (though not cracked) so what I did was replace the O-ring from the "water inlet fitting"( and that term came from the manual you provided) and to be on the safe side added some gray sealant. I ended up replacing my timing belt and water pump and I can truly say it is "no joke" doing it. So many parts to remove just to get to the belt and pump.

My timing belt still looks okay on the ribbed side but the other side was showing tiny tears so I'm glad I went and replaced it. The water pump gasket however is not so good. There is coolant, although very very little, that dripped from the water pump drain channel onto the belt and tensioner side so it definitely overdue. By the way my 2001 montero is a couple of hundred miles short of reaching the 90k mark. Having those special tools from the manual would have made my life easier so advice to those who want to replace it themselves, get it or something similar to it or like what I did get creative, before you start this. I ended up borrowing tools and having a friend help me, especially when putting the parts back, because it can be very frustrating doing it yourself. Example is having someone hold the A/C condenser and steering pump while you put the bolt in and tighten it, not to mention handing you tools, is a must!

I'm still not done putting it all back. I'll try to finish everything tomorrow because I need this done for a trip this weekend, 15hr drive one way, so you can understand my desperation in doing this myself. This reminds me, I also had the flashing differential light happen before all this and I have read in one of the post regarding transfer case switch failures due to connection corrosion. The same friend gave me advice on a similar problem he had worked on before and his solution was putting di-electric grease on connectors exposed to water getting to it. I'm going to try applying this first before I start buying replacement switches and see if it will fix the problem temporarily(hopefully permanently). I will post my update as soon as I get my "monty" running. Thanks again for the help!

Here are pics of the new water pump along with two tensioners I've replaced...