Losing coolant

[zzyzzx]

Car in question is a 1999 with 25,150 miles on it, and all original except for the battery, serpentine belt, and it's had some oil changes. Besides the LIMG and overflow coolant tank, given the age and mileage on it, is there any particular places I should look? This is a backup car that I don't even keep at my house (I live in the city) but so far I haven't noticed leaving any coolant anywhere. I am suspicious of the cooling reservoir because the some dampness I saw running along a seam below it. Dipstick looked OK, but it was getting dark at the time i checked it. There was some crud on the oil filler cap, almost looked like I had mixed oil and corn starch, or something. I can't quantify the leakage rate since I rarely drive the car. What coolant I can see looks fine. The car runs perfectly, but if I'm not supposed to drive it in case it has LIMG, then I won't except to move it around the yard. Any advice?

[zzyzzx]

It's definately the LIMG gasket. I ran it and watched the coolant slowly leak out from the engine at the gasket location.

[rustyballs_69]

http://grandamgt.com/forum/showthread.php?t=68087
That will help you out. There are somethings that I do different than angrysk8r did.

When draining the coolant it is easyer to just pull the lower radiator hose off then mess with the drain cock.

When your pulling the upper intake you can leave the throttle body on the upper intake. Just pull the two coolant hose off the throttle body.

The coolant tube that comes out of the back of the t stat hosing doesn't need to be pulled out. Disconnect the rubber hose from it and remove the 13mm nut that holds the tube to the rear head.

Get a block of wood and a jack and put it under the oil pan. Lift it up just a little and take the passanger side motor mount out. That way you can get to the 3 bolts that hold the power steering pump on with out the use of a swivel. Once the power steering pump is off just set it up on the strut tower. You don't need to take the lines off.

Don't mess with the rocker arm till you have the lower intake manifold off. Then use the tool to lift the rocker arm up and pull the push rods out. Make sure you don't mix up the push rods. I would put 12 holes in a box and lable the box front and rear. That way the push rods go back in the same place they came from.

[zzyzzx]

Am I going to need crow's feet to do this?

[Nate's Alero]

no

[01silveralero]

http://grandamgt.com/forum/showthread.php?t=68087
That will help you out. There are somethings that I do different than angrysk8r did.

Get a block of wood and a jack and put it under the oil pan. Lift it up just a little and take the passanger side motor mount out. That way you can get to the 3 bolts that hold the power steering pump on with out the use of a swivel. Once the power steering pump is off just set it up on the strut tower. You don't need to take the lines off.

Don't mess with the rocker arm till you have the lower intake manifold off. Then use the tool to lift the rocker arm up and pull the push rods out. Make sure you don't mix up the push rods. I would put 12 holes in a box and lable the box front and rear. That way the push rods go back in the same place they came from.

You dont really have to lift the engine up a little and remove the motor mount. You can get to the bolts but you cant really use a long extension to remove the power steering pump. You will need a swivel 10mm shallow socket to get the 4 corner bolts off and also back on. You could use a wrench using the 12 point side and put a bigger wrench over the other end of the 10mm wrench to lock into the 10mm wrench to help remove the bolt.

Whatever you do DONT mix up the pushrods. It will cause my headaches then it is worth. The intake pushrods are the short ones and the exhaust are the longer ones. If for some reason you mix them up you can follow the port that is directly behind the pushrod location. It should be E I E I I E in the rear of the engine E I I E I E in the front.

Depending on how long it was leaking and if any coolant was lost (can't locate from where though) it is recommended to remove the heads and get them checked. It would save the hassle of having to do the whole thing over again.




Whats needed
10mm for intake bolts
13mm or 1/2" depending if you decide to remove throttle body or not.
9/32" for map sensor
5/8" alternator mounting bracket
needle nose pliers
8mm or 5/16" for coolant return line / battery and such.
MAGNET for when you drop bolts lol
13mm or 14mm to remove coil packs.
Patience putting it back together so you don't mess up the order of pushrods or break a sensor.

[zzyzzx]

Stupid question:

Do the pushrods have to go back in the exact same place? Or is a long one a long one and s short one a short one and they are interchangable as long as you use the right size.

[01silveralero]

That isnt a stupid question. It is preferred to keep them in the same location. It wouldnt really hurt though if it didnt put the pushrods in the same spot. If lifters were removed they would have to go in the exact same spot because of how the cam wears into the bottom of the lifters.

[zzyzzx]

I also have a question about the usage of the U-joint thing for the power steering pump bolt removal. It's unclear as to if I even need that or will a regular swivel head ratchet work?

[TheThickster]

you should check the coolant hoses that run into the throttle body for leaks. mine were leaking on my 3.4 i went ahead and capped them off since it never ever freezes here anyway.

[zzyzzx]

you should check the coolant hoses that run into the throttle body for leaks. mine were leaking on my 3.4 i went ahead and capped them off since it never ever freezes here anyway.


You are referring to those small metal hoses, right? Mine ae not leaking, but they do look all rusty.

[zzyzzx]

You dont really have to lift the engine up a little and remove the motor mount. You can get to the bolts but you cant really use a long extension to remove the power steering pump. You will need a swivel 10mm shallow socket to get the 4 corner bolts off and also back on. You could use a wrench using the 12 point side and put a bigger wrench over the other end of the 10mm wrench to lock into the 10mm wrench to help remove the bolt.

OK, so you are saying to use this:
http://di1.shopping.com/images1/pi/1b/56/dc/54636377-149x149-0-0_SK+Tools+S+K+Hand+Tools+SKT40560+3+8in+Drive+Sta nd.jpg


As opposed to using a universal swivel adapter and a regular socket:

http://s7.sears.com/is/image/Sears/00923766000-1




Depending on how long it was leaking and if any coolant was lost (can't locate from where though) it is recommended to remove the heads and get them checked. It would save the hassle of having to do the whole thing over again.

The total amount of coolant lost is roughly equivalent to filling up the reservior twice. From what I can tell from reading on the internet, I'm catching this early.

[zzyzzx]

you should check the coolant hoses that run into the throttle body for leaks. mine were leaking on my 3.4 i went ahead and capped them off since it never ever freezes here anyway.

Are you referring to these hoses: Should I be concerned about the rust?

[zzyzzx]

This is where it is leaking from, which I think is the LIMG gasket:

[Ryan from Ohio]

Thats the side of it.

The flat parts in the valley get just silicone.

Use the good gasket set to.

[zzyzzx]

Thats the side of it.

The flat parts in the valley get just silicone.

Use the good gasket set to.


I was showing the side of it because that's where I can see it leaking from. It's probably leaking from other places too.

In so far as the gasket set, I got the FelPro set along with the bolts. I suspect that I still need the EGR gasket though.

More questions:
Do I need to drain the oil to complete this job? I am not necessarily convinced that my oil has been compromised yet, and I really just want to get the car running first, then change the oil. Is this OK, or will oil spill all over the place if I don't drain it first?

Is this something I can do a little at a time every day after work, of should I try to do it all over a weekend? Or does that even matter? Seems to me that a nice after work type of thing for day 1 might consist of only draining the coolant and removing the splash shield. The Alero isn't my only car so I can use my daily driver car to get to work, etc.

Yeah, I'm finally getting around to doing this, I just put the car into a garage on Sunday afternoon.

[Gr1m]

ya thats what usually goes bad is the RTV on the side there and on the other side

[zzyzzx]

Why does the throttle body have cooling lines going to it?

[Afugy]

Why does the throttle body have cooling lines going to it?

To cool it down, duhhhhhhha. :jk:

Because of the EGR being right there, it needs cooling.

[zzyzzx]

Exactly how do I remove those two bolts on the back coil pack plate? They are under a wiring harness piece, and even when I undo the two clips that hold it in, that doesn't seem to help.

If it matters it's 13mm, not 14mm on these two bolts. By putting my arm around the alternator, I got the one close to that. It's the one on the drivers side that's giving me the most trouble (although both of these are terrible to get to).

[Cliff8928]

Why does the throttle body have cooling lines going to it?

So the throttle plate doesn't ice up in extreme cold temperatures.

[zzyzzx]

OK, not how do I get the UIM nut off that's near the alternator? There seems to be a power steering line that's in the way. I can fit a 13mm closed end wrench on it, but I can't move it. Would a ratcheting wrench work here?

[zzyzzx]

OK, finally got the UIM off. Will most likely not put that stupid nut that gave me problems back in that same spot and replace it later with a regular bolt that I'll get next time I'm at a junkyard. That's the second thing where the car does not exactly match the factory service manual. I assume that as long as I have the UIM out, I should clean it really good (not that it's particularly dirty, but I always do that). How do I clean out the insides of it?

Also, I assume that this car as double platinum spark plugs that I won't have to replace anytime soon? Seems to me that you can't do anything behind the engine without removing the alternator and coil pack, at the very least.

[cherrington17]

to do the plugs, you don't need to remove the alt.. but moving the coil packs does help.

i'd take them out while your there, and inspect them. If you do have one or two bad ones, you'll kick yourself for NOT doing them now.

You are following this, right?
http://www.grandamgt.com/forum/showthread.php?t=68087&highlight=lim+gasket

[zzyzzx]

You are following this, right?
http://www.grandamgt.com/forum/showthread.php?t=68087&highlight=lim+gasket

To an extent, yes. But just like the factory service manual, it's sometimes wrong, or not applicable since I will be using the special tool to remove the push rods.

Another thing I'm going to have to research is the LIM torque specifications and order. I see multiple postas about the correct torque specifications, but nowhere have a seen an actual diagram about what the correct order is (I know the difference between the vertical and diaginal ones, but within those groups, there is still an order. That and exactly where to (and not to) apply the RTV.

[cherrington17]

use the new torque specs... the 4 on the sides get torqued down more, then the centers.

I'd message whitev6 or nate for the proper order.

[zzyzzx]

How much coolant is going to come out when I remove the thermostat housing from the LIM? Is there a good way to catch it?

Now that I've inspected it with the UIM off, I can see that the LIM is exrernally leaking all over the place on the sides where there is the RTV only part. Those diagonal LIM bolts are in some dirty areas!

[zzyzzx]

What's the white crap on the 6 UIM bolts?

[cherrington17]

thread lock. so seal the bolts in the holes.

also, your suppose to drain the coolant in like... the first step. :lol: After doing that, i had 0 coolant coming out of the thermo housing.

[zzyzzx]

thread lock. so seal the bolts in the holes.

So put blue threadlicker on the UIM bolts?



also, your suppose to drain the coolant in like... the first step. :lol: After doing that, i had 0 coolant coming out of the thermo housing.

Yes, I drained the radiator, but not the engine block plugs. Just looking at the hoses, I would think there would still be some coolant left in the LIM and probably in the thermostat housing as well.

[zzyzzx]

Another website with a bunch of in progress pictures:
http://community.webshots.com/album/125871974XzTxrQ

[cherrington17]

you need new UIM bolts. (as per....everyone) i'm not sure if threadlocking the old ones will suffice.

and i didn't drain the engine bolts either. If you drained using the plug in the radiator, that is below the thermo housing. there shouldn't be any above that.

[zzyzzx]

you need new UIM bolts. (as per....everyone) i'm not sure if threadlocking the old ones will suffice.


The new bolts are for the LIM, not the UIM. In so far as the LIM bolts, plenty of people have reused them and applied new threadlock, but I figure that's for more experienced people than myself.

[cherrington17]

UIM gets new bolts too. should be in the kit.

[zzyzzx]

If you drained using the plug in the radiator, that is below the thermo housing. there shouldn't be any above that.


Hose between the thermostat housing and radiator goes up (as in up going towards the radiator), so I don't see how it could drain out.

And reason why the LIM has '99' on it? Do they really very from year to year?

[zzyzzx]

Just found another website with a bunch fo good pics, along with their theory of why these gaskets fail:

http://www.agcoauto.com/content/news/p2_articleid/90

http://www.agcoauto.com/content/images/topics/left%20intake%20leak.JPG

http://www.agcoauto.com/content/images/topics/right%20intake%20leak.JPG

Those leaking coolant pics are exactly what I see.

[zzyzzx]

Another good How-To with lots of pictures (althgh no Alero):

http://www.handymanlyness.com/archives/auto/repair/engine_mech/intake_manifold/GM_truck/gasket_replace_99_Jimmy.html

[zzyzzx]

I found the bolt sequence in the Factory Service manual. You don't do it like an oil pan or anything, you work from the inside out. It also mentions nothing about using new bolts. It says to put on threadlocker! I should probably get then and type them in here, but at least it does to do the vertical ones first. Nothing about doing it in steps like the new procedure.

Factory service manual says:
An oil leak may result if the vertical bolts are not tightened before the diagonal bolts.

1. Tighten the vertical lower intake manifold bolts (1) to 13N·m(115 lb in).
2. Tighten the diagonal lower intake manifold bolts (2) to 13N·m(115 lb in).


From what I've been able to gather over the internet, the revised method is:

1. Tighten the vertical lower intake manifold bolts (1) to 7N·m (62 lb in).
2. Tighten the diagonal lower intake manifold bolts (2) to 7N·m(62 lb in).
3. Tighten the vertical lower intake manifold bolts (1) to 13N·m(115 lb in).
4. Tighten the diagonal lower intake manifold bolts (2) to 25N·m(18 lb ft) or (216 lb in).

I'm providing the conversion to lb in on #4 so you maybe don't have to bring an extra torque wrench.

I've also read something about a 30degree thing, but I'm not completely sure where that comes from and don't see it often.

[zzyzzx]

Don't mess with the rocker arm till you have the lower intake manifold off. Then use the tool to lift the rocker arm up and pull the push rods out. Make sure you don't mix up the push rods. I would put 12 holes in a box and lable the box front and rear. That way the push rods go back in the same place they came from.

Is it even possible to mess them up if you are using the tool? I mean is there even enough extra slack to put a longer one into where a shorter one goes if you are not removing the rocker arms?

[cherrington17]

yes, absolutely do the "revised" torque specs. The old ones lead to it leaking again.

[zzyzzx]

Just got the front valve cover off. Now it's really obvious that my oil looks like peanut butter. Viscosity seems OK, but the color is way off. The oil is as if someone mixed some orange color in it.

[zzyzzx]

Are you sure I won't need crow's feet to get to those diagonal LIM bolts? That one near the fuel rail looks like it might need it.

[zzyzzx]

OK, I got the LIM off. I will definately need some crow's feet. I don't see any other way possible to get two of the diagonal LIM bolts torqued properly without it.

Also, the LIM gasket in there looks perfectly fine. I believe that all my leakage problems were due to improperly torqued diagonal LIM bolts, since that's where it was leaking from. They were not finger loose as I have heard mentioned elsewhere though.

[zzyzzx]

I finally got the car back together last night. It started right up, and I ran it (in a garage) long enough to warm it up. It runs fine, as per it's usual. I did not drive it though. I see no sign of any leaks. Only strange thing is that I'm reasonably sure that I removed more coolant than I put back in. I saved the old coolant in used 2 liter soda bottles, so I know exactly how much I took out (and I do that to take the stuff for disposal as well, it's the only bottles I trust in the car like that not to spill).

I tried opening the bleeding screw while running and all I got was more coolant coming out of that. I assume that my recervior will empty out a couple of times while driving and that will be it or should I research how to properly bleed out the air, assuming that there is some. should be 1-2 liters worth.