Does anyone have a map of the LQ1's cooling system?

[Nas Escobar]

I notice when I turn on the car or turn it off, I get a leak from the cooling system. At first I thought it was the heater hose quick disconnect, but turns out it may be somewhere else, somewhere further down. I notice the leak from the edge of the subframe and it runs down, but don't know where does it fall to the subframe. I don't see anything wet in front of the front valves, I just know its' a moderate leak and it happens every now and then. It's not an everyday thing.

 

Where could this intermittent leak come from?

 

All help is appreciated.

[Night Fury]

Heater lines that run along the subframe are a common culprit

[Nas Escobar]

Those are made out of metal right?

 

BTW, the leak is on the driver's side

[Psych0matt]

Those are made out of metal right?

 

They are. I had to fix it on my cutlass, and the monte had already been fixed, they just ran a rubber hose up along the passenger side instead of underneath. It worked though.

[pitzel]

Dorman makes a replacement "lower heater hose" which replaces all the metal stuff. Comes in a big box, but doesn't cost too much and really isn't that difficult to install. Hardest part for me was disconnecting the main harness after you rock the engine forward and remove the hose clamps.

[Nas Escobar]

So this shit got intriguing... I decided to look further in to the leak today to see if they were any lines near the subframe. I didn't see anything leaking, but I did notice the water runs down (or at least I think that's how it goes) to the subframe near the starter area. From what I can gather it's under the plenum, but not near that annoying little hose under the throttle body. It's more in the general area of the picture below this post.

 

Do I need to redo the LIM, or is something else failing there?

[Nas Escobar]

I tried getting a picture of where I see the drips but its somewhat hard to focus in there.

 

I do wonder if this and the EGR3 thing with the loss of power are related. The leak didn't show up until right before the EGR3 issue started.

 

I remember last time I had issues with this engine, I had the o2 sensor code despite it being a leak in the lim gasket.

 

I should also note that the leak goes away when the reserve bottle empties itself, but the radiator never ends up empty itself.

[mfewtrail]

Rent/borrow a pressure tester and you should be able to find any external leaks rather quickly.

[Nas Escobar]

Would have never found it with that damn intake manifold on. It was the LIM that's bad again. Gotta swap it out... so I guess this thread is as good as done.

[GnatGoSplat]

You were able to confirm it was the LIMG? I'd suggested it awhile back in the Whatever thread, but that was just a guess based on the wetness in the valley. I'm having to do this job for a 3rd time. Sure hope there won't be a 4th.

[Nas Escobar]

Once the intake was off, it was clear as day. The path where the coolant runs in the intake was wet on the rear bank. I drained the LIM, took it off and now I have no "random leaks". Only thing is I didn't drain the block, but I KNOW where the "new" leak is, and it's somewhat logic. Only thing is that the weather hasn't been cooperating so I'm about a week into this. I am however painting the valve covers so it's not THAT bad.

[GnatGoSplat]

Well, glad you found the problem at least, but I'm sorry you have to do it again. Yep, rear bank is also where mine was leaking from. My LIMG started leaking about the time I wrenched that new quick-disconnect fitting onto the LIM. I think all the pressure on the LIM must have hurt the gasket. I already had the plenum off because of the bad FPR anyway so it's just a little more work. No leaks from the oil manifold gasket on yours? When I pulled the LIM, I noticed mine looks leaky so that's what's holding up the job on mine. I had standing oil in both of the channels on either side of it.

[Nas Escobar]

It's not that bad. What sucks is I have no garage so I'm limited by the weather and daylight hours.

 

It's funny you say that, mine started leaking after I fixed the heater disconnect hose leak. I guess doing that job in the winter didn't help me either.

 

Not sure where that gasket is. I did notice that there was oil in the throttle body before I even started this job. Not too sure what that's about.

[GnatGoSplat]

Oil in the throttle-body could be the PCV system. Apparently it's well-known that these engines suck up a lot of oil through their PCV system. There was a TSB about it that required a new front valve cover. You could also try replacing the PCV valve and see if that helps.

 

Oil manifold gasket is the gasket beneath that plate in the valley that has the "L" shape on it, a PCV nipple, and 7 bolts hold it on. You can see it in this pic: http://img.photobucket.com/albums/v336/AaronZ34/100_0306_zps89e6a27e.jpg It sits up on sort of a little platform on the block. In the low channels on either side of that little platform, mine had oil pooled up there.

[Nas Escobar]

It's never done it before, so I'll try the PCV valve. Is the PCV where the TPS is located?

 

I always wondered what that L shaped thing was. I never realized there was OIL there. Mine isn't leaking there. Mine's clean although it did have debris there but no oil. Coolant, yes towards the end but no oil.

 

Now I'm scared since you stated there's no one that carries that gasket. I may have to start hoarding LQ1 parts. Although, I do wonder how good RTV would be at making a "new" gasket.

[GnatGoSplat]

PCV is located inline. It sits in the plastic vacuum harness and has a hose coming out of it which attached to the plenum. On the TB side of the plenum, towards the back is a spot with 2 vacuum hose nipples. The larger one, a hose was attached that is about 5" long and curved. The hose is attached to a little metal cannister whose other end sits in the plastic vacuum harness. The little metal cannister is the PCV valve. If you shake a PCV valve, you should hear/feel a rattling inside. If you don't, it's definitely bad. If you do, that doesn't guarantee it's good, but it's not for sure bad. It's not expensive so you could replace it anyway if there's any doubt.

 

I'm hoping GMPartsGiant comes through with that gasket, but being they're getting it from a warehouse of vintage discontinued parts, they may be in limited supply. I bet it should be possible (though very time consuming) to carefully cut one out of bulk gasket material using an X-acto knife using the original as a pattern. Though what kind of gasket material you'd need, I have no idea. It's a paper-looking gasket, but needs to resist oil and oil pressure. I suppose some RTV might do a good job. I used a Permatex High Pressure oil-resistant RTV to seal up the oil pump drive 2yrs ago and that seems to have done an amazing job. That possibly could have worked on the oil manifold gasket, but I wanted to get the right part if it's still possible to get. It did last 20+yrs and 198k miles so hopefully doing it once with the right part will be the last time I'll need to do it.

Edited November 12, 2014 by GnatGoSplat

[Nas Escobar]

So I got the engine put back together and I have an issue where the heater hose quick disconnect line leaks now even though I just put in a brand new piece. Am I missing something? I even put in an O ring at the end of the clip that's always breaking. It's a steady leak too. Last time I changed that, I didn't have this many issues with the clip. Any advice?

Edited December 11, 2014 by Nas Escobar

[GnatGoSplat]

Which part of the quick disconnect is new? The whole thing? There should just be 1 O-ring that goes into the female end of the quick disconnect first, and then followed by a plastic collar ring. There should not be an O-ring at the end of the clip.

[Nas Escobar]

I bought the whole thing. The last time, I put an O ring at the bottom of the clip and that didn't cause issues. Actually, the one that was there from who knows when was like that and had a bunch of other plastic stuff on the heater tube.

 

I basically put in the O ring at the top of the pic. You're saying it's not needed?

[GnatGoSplat]

An O-ring does need to go into the fitting, although if you bought the whole fitting, the O-ring should already be in it. No extra O-ring is needed and at the end of that clip isn't where the original O-ring is supposed to go. Inside the fitting itself, should first be the flow reducer, then O-ring, and finally a plastic collar/spacer that kind of holds the O-ring in.

 

If nothing fell out of the new fitting, everything inside it should already be where it's supposed to be and you just snap that white clip onto the end of the pipe and push it into the fitting till it clicks and you're good.

[Nas Escobar]

I tried it that way as well and it still leaked. I tried pushing the heater hose in and it still leaked when pressurized.

 

Maybe the fucktards at Advance gave me a bad one? They're known to do that.

[GnatGoSplat]

Was it a Dorman 800-401? You can pull that first plastic ring out and then the O-ring to confirm those are in place the way they're supposed to be.

Also make sure it's not leaking at the threads.

[Galaxie500XL]

I've seen poorly place Teflon tape cause leaks there....it does have Teflon tape on the threads, right?

[Nas Escobar]

It was a Dorman 800-401. The first one they gave me had no o ring. The 2nd one did and still leaked.

 

They both leaked where the disconnect tab was. I actually torqued that socket to the specs on the service manual and still leaked.

 

I got fed up of it. I've dealt with this issue since the first LIMG job I did on it.

 

I did this instead.

 

 

I originally was just gonna use a small hose to hook up the factory hose to the barb but there was no space to actually put it in... so I ended up doing this

 

 

Now I won't be dealing with any more leaking issues from there. Heat is a lot warmer too. I used to still be cold setting the climate control to 90, now I'm fine at 80.

Edited December 13, 2014 by Nas Escobar

[GnatGoSplat]

You may want to add an inline heater hose restrictor. I've read that full pressure going to the heater core may eventually kill it.

Fords have a restrictor for the heater core as well and there was some debate as to whether it's needed.

http://www.ford-trucks.com/forums/1125252-heater-core-restrictor.html

Since the quick disconnect has a restrictor in it, the concerns Ford people have may apply to us as well.

I replaced my quick disconnect fitting for the only reason being that the restrictor in my original one crumbled apart.