Hi, I would love some help/guidance from the pros, thx!

MODEL: 2002 Montero LIMITED
PROBLEM: Minor Coolant Leak

I've been having relatively minor coolant leak for about 18-24 months, have just been topping off my coolant level every 3-4 weeks or so, never been a big issue, other than this being an annoying chore to remember. Today, during an oil change, I asked my mechanic to take a look at this issue to see if it's something I need to take care of. Upon inspection, he said there's definitely a minor coolant leak, but he's not sure exactly where -- he believes it's a "bad metal pipe" BELOW the intake manifold, but he's not able to access and inspect it closely without taking the thing apart. He called around to see if there's this part he can replace, but couldn't source it out, so he didn't wanna risk opening up the thing. He said the leak will definitely get worse and thinks I should get it fixed soon, but he's not sure how -- he says the pipe looks a little rusted, and with the "pressure test" he saw minor drippage. But he said it might be a discontinued part! I asked him what's the name of this metal pipe, so I can help source it on my own, in case he needs to get in there (so that I've got the part handy IF, in fact, it's a bad pipe), but he said he doesn't know the name of the pipe!

Can anyone help? He said it's a metal pipe below the manifold, but he couldn't say what it's connected to ...

Just wanna start early and try to source this metal pipe out, before the leak becomes a bigger issue. He said I should be OK just topping off, but he wants me to pay attention to see if I'm needing to top off more and more often, etc.

ALSO, any pics, videos, and/or OEM part numbers would be awesome! Thanks!

 

There is a crossover coolant pipe on the back of the engine. However, the leak you observe on top of the engine is likely coming from elsewhere. The crossover pipe is BEHIND the two banks of the cylinders and below the valley of the engine. Any leak from that pipe will run down the backof the engine and will not accumulate on top.
There is an additional pipe coming from the crossover pipe to the front of the engine to the thermostat housing.
While it is possible that the ether one of those pipes get rusty, it is not very likely - they are desined to operate with water/coolant constanty flowing though them. They do get discolored but no rusted. What is much more liky to happen is one or more of the gaskets and o-rings deteriorate over time and that is where the leak occures. Have your mechanic replace the o-rings first. Easy job and likely a fix. Here is the schematics of that area.

 

Thanks for this info!

I don’t know my way around down there, but he did say it’s a metal pipe BELOW the manifold, so I’m not sure if that is on top of the engine or not?

OK, next time I’ll suggest that he just replace the O-rings, not sure if that is an expensive job, will see what he says.

ALSO, i’ve been monitoring my coolant levels in the last four weeks since I saw him, and it has not gone down significantly at all, and I have not noticed any leakage on the pavement, so does it look like I’m OK for now? I guess what I’m asking is, if my coolant level in the reservoir is good, is that a good indication that there is not significant leakage, or is that a misleading perspective and that I might in fact be leaking a lot of coolant from another reservoir?