hi
in order to total drain the coolant out of the block you have to remove the knock sensors but one is in the middle of the block next to the trans a 7/8 crow foot will work 12 point but its tight need a universal joint on it to snake it in there then those metal fingers to snake it out to put more pipe sealer on the threads there is 2 one on each side of block just changed them out on my regal if you have questions

Hi, when you say "drain the coolant out of the block", do you mean drain the coolant in order to completely drain the coolant(complete coolant flush)? Or when you say that, do you main the coolant could be in the block where it leaked in due to failed lower intake manifold gaskets? Sorry for any stupid questions, I like turning wrenches but have never broken down a car engine before.

Also, I think I was not clear in my first post as to why I might drop the oil pan. It is mentioned in a LIM/UIM guide on a different forum on how to expel coolant from cylinders/freshen up the oil in the bearings. They mentioned dropping and cleaning the oil pan as well. See attached image to this post for the excerpt that includes this.


I have done a lot of reading on the UIM/LIM gasket replacement before starting this thread and decided on this list of parts for the job:
APN Upper intake plenum(w/ metal shielded stove pipe) GM Intake Manifold Kit
Black OEM throttle body gasket(because it is softer and said to work better than the one that comes with the APN Plenum. Because the stiff one with the APN kit makes the plenum flex)
APN kit comes with lower injector o-rings.
ACdelco aluminum framed LIM gasket
Dorman aluminum coolant elbows
Valve cover gaskets: FEL-PRO Part # VS50080R

Extras while I'm in there: thermostat & seal, PCV valve.

Have all of it in my cart on rockauto ready to order.

I read that exert that you posted a pic of, I don't see anything in it that says to drop the oil pan, they say to drain the oil via drain plug, remove oil filter, and all spark plugs, then rotate the engine a few times with a wrench, the refilling with oil, disconnecting the ICM and giving it a crank or two via key to get fresh oil to the bearings, to be even safer you could change the oil again in a few thousand miles.
Dropping the pan would be a bit of an extra precaution, but it is not necessary, if you got a lot of coolant in your cylinders you'd know it, as it would have hydro-locked.

Also, that APN UIM is the best part you can go with, but IMO it is not necessary as long as you install the reduced diameter EGR Stovepipe, I opted to do this and saved like 40.00.
Judging by how little mine had warped around the EGR port in 136,000 miles, I am pretty sure the Dorman replacement I went with will hold up for the rest of the life of the car.


As for a full coolant flush, and going with typical green coolant, not trying to start another debate about it, but I opted to so a partial flush, and go with Dex again, as I am not sure it is more of the coolants fault problems occur, or the owners neglect to change the coolant when necessary, to make sure no air is in the system, and to not mix coolant types.
Of course many will disagree, and curse Dex-Cool, but I look at it like this, if it was more of the coolants fault, why did they redesign the LIM Gasket, and EGR Stovepipe, rather than to change the coolant.

Also as for the rubber side gasket things for the LIM, I used them and have never had an issue, and many others have used them as well, I suggest using them and not relying on RTV along, mine did not move, fall off, or cause any leaks in the 136k they were on the car before I replaced the LIM Gasket, and so far they have not caused an issue at all.

Last I've researched. Coolant type is not the issue with the gaskets. It'* just a design flaw with the gaskets themselves. They don't tolerate heat/cold constants all the time and they fail. You'd be surprised at what chemicals plastic can tolerate. Including acid.

I'll second the runner gaskets. The gap between the LIM and engine block is too great for RTV alone to fill the "gap". RTV is only good up to 1/8". Otherwise, pressure or vacuum can pull it out.

You guys are referencing the shorter rubber pieces that come with the typical LIM gasket kits, correct? They come with the acdelco kit I want to get. See the link, they are the orange pieces, correct? More Information for ACDELCO 89017816
RTV is required at both ends of those pieces, correct?


In reference to the oil pan..oops.. I guess it is not in that excerpt. Just checked and they actually said to drop the pan if you end up dropping crap into the crankcase.
That leads me to my next question. How worried should I be of dropping stuff into the engine while the LIM is off? Is it easy to do while you are scraping old gasket material off the sealing surfaces? I don't even know what the proper terminology is. The LIM gaskets sit on what..? and the passages through the LIM gaskets are what..? What is the space between the two LIM gaskets?

Yes those orange rubber parts are what we are talking about, when you install them put a good gob of RTV on each corner before placing them down, then a good glob on top of them at each corner.

With the LIM Ports, I'll try to get a pic and label the air, and coolant ports on it for you, when you pull the LIM off just get some old towels and cover the lower end of the motor so you don't drop anything into it, then you can clean any old gasket material from it.
I think there are some pics in my old thread I have you a link to, I just used an old towel to cover the balancer and all, and stuffed some rags in the other ports.

Oh yeah, I forgot about a video that may help you, it is for a L67 Supercharged motor, but after removal of the Supercharger the rest applies to your L36.
http://www.cpaclubgp.com/misc/lim-gasket.html

You may need VLC Media player/plugin installed to watch it, or use the link under the video box to download the video, then play it with something like VLC, or Windows media Player.

i dont think its a big deal either way, i do it on small blocks too. because they come with crappy gaskets that blow out. the 3800 gaskets though have little dots and ridges that hold it in. so on the 3800s i have done i used it and put some extra black silicone on top of it and below it.



as far as the redesigned UIM, the dorman comes with all the new design stuff and is thicker where the oem one cracks.

No, its not required to drop the oil pan. Best practice is to lay shop rags in the lifter valley after you get the LIM off the engine. This is to catch anything while you remove old gaskets. Do not worry about coolant going down into the lifter valley. Once you have installed everything, now you can drain all the oil out, change the filter and put new oil in. Some people will change the oil again in a few days.

And BTW, yes, I have been pulling Regal Guy'* posts because he is not posting correct information. Draining the engine of coolant via the knock sensor ports is not required. And the LIM rubber runners that we said to install, are there for a reason. So install them. Using gobs of RTV will only create problems should a gob of it fall into the lifter valley. The only place you need to install RTV is the 4 corners where the runner meets the manifold gasket. This is to create a seal between the 2 gaskets.

The redesigned Dorman one is what I went with myself, they are considering the APN one because of the problems with the EGR gasses warping the area coolant passes through, which makes that added steel bushing an extra piece of mind, I'm not sure I'd pay 40.00 for it myself though, I considered getting a steel bushing and cementing it in there myself, but decided the reduced diameter EGR Stove-pipe addressed that problem well enough.


Also, Mike, when I said gobs I meant a decent amount that is enough to seal each corner, I am pretty sure you were referring to the suggestion of using just RTV, but just in case, since I did say gob as well, I only meant a reasonable amount to seal it, to much is as bad as too little..

No sir, your correct. I understood you meant dabs in each corner. But someone else was saying not to use the parts and just gooping the snot out of the rails. Which is bad info.