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Discussion Starter #1 (Edited)
I recently had a coolant leak that seemed to be seeping up the 2nd Bolt back from the front on the driver Side. I know by design, this seems impossible but is the only explanation I could find and the evidence I found showed that.
No Leaks since it was replaced....See this thread.....

http://www.impalassforum.com/vBulletin/34-engine-problems-maintenance/1308561-intake-manifold-gasket-replacement-s.html

Bolt showed signs of leakage and there was NO other area the leak was coming from. Anyway, this was my first time pulling an Intake off a LT1 engine and just wanted to share some pics and little tricks I found along the way to maybe help others.

The basics of the intake removal are straightforward and believe the Haynes manual walks you through these steps, so not going to cover each here. However, just some general observations, I did remove the Fuel rail/injectors first to gain a little better access to certain areas of the manifold. This also made it easier to get to the EGR valve and EGR Tube Nuts on the back of the Intake. I chose to remove the EGR before removal and install after the intake was on the car.

Once intake was removed, I also remove the Studs from the back of the intake so that it was MUCH easier to remove all the old gasket material from those areas. I’ll include a pic of those mount areas after cleanup. It’s easy to do if you just use 2 nuts on the stud and tighten them against each other. Then use a wrench on the nut closest to the intake to back out the stud. So much easier to do this than it is to clean around the Studs with a scraper.

I also noticed that the 2nd intake Bolt back on the passenger side that secures the Coolant metal tube seemed a little too long and doesn’t need to be. I really had to flex and lift up on this metal tube to get the bracket to clear the Stud. This Bolt has a nut on the end that secures the coolant tube to the intake, but after removal of the Nut, you got to lift it up a lot to get it to slide off. I’m sure this tube is pretty brittle and doing this also stresses the back Banjo bolt area too. So before reusing that bolt, I cut a good bit off the top so that there was just enough thread to slip the bracket over and secure the nut. Anything more than that seems useless and lifting more than needed could cause other repairs that could be difficult to get to at the back of the Heads.

When scraping the Heads and the end rails clean, be sure to lay something in the Lifter Valley and plug up the intake ports to keep debris out. This is pretty common knowledge by most. However, be sure that in the lifter valley you push the material back in and under the inner manifold bolt holes in the heads. These are wide open into the valley and any scrapings that fall thru these holes, could end up in the valley area and you may not see them. If your rags/blanket/whatever are tucked in there real well, nothing should get past it and slowly pull the edges of your cover over itself before removing from the valley area. A good idea to have a vacuum handy and visually inspect the valley area that nothing got past your cover. I also like to hit each intake port with the vacuum before pulling out the towels stuffed in there. Also, be sure to run a Tap down all the bolt holes to clean them up good. Keep in mind that those center bolt holes in the head just go into the lifter valley so have something below to catch the junk. Used a little compressed air to blow out debris from the 4 Corner Head Bolt areas that are just a closed off pocket.

When installing the intake, it is important that you “Drop” the intake manifold straight down onto the Heads/Block and not disturb the Gaskets or RTV. I’m a big guy but even this light Aluminum Intake can be a handful if you’re not careful. I tried a few dry runs before applying RTV and just did not feel confident that this would not get messed up. So, what to do? I got a cheap material Bolt, something easy to cut…think it was 3/8 - 16 thread and cut the head off and then cut 2 pieces about 1” long. So basically made 2 little all thread rods. Threaded each 1 into the front 2 holes of the Heads and left a little sticking up. The idea here is to use those on the front 2 holes as locator pins and while keeping the back of the manifold lifted slightly, then let the back end tilt down into place….worked like a Champ.

If doing this, keep in mind that the angle of the bolt holes combined with the intake will not allow you to have these stick up very far. What I did was cut them so short that none would stick above the intake manifold when installed. They were just threaded in finger tight but nothing to grab once the intake is installed. So I just took a HackSaw and cut a little slot on top of the end so I could use a Screwdriver to reach down inside of the Intake Bolt hole and unscrew the stud til I could grab it.

One last thing I did while the intake was removed was to beef up the Oil Pump Drive housing a little. I was going to get fancy and make something to surround the plastic but it’s a tight area up against the Block wall. Instead, I just went with a Flat Stainless Washer I had laying around.

My only regret, I didn’t have more time to clean up and Paint the intake manifold. But if I could offer any other advice to hopefully prevent leaks/problems….take your time and CLEAN EVERYTHING. I took each bolt, placed it in a vice and Wire brushed the threads, hit them with brake clean and then applied the correct PTFE Paste to the threads. Clean the Heads and the end rails very well too as well as the intake rails and wipe it all down. Run your finger over the flat surfaces and remove any burrs. The intake manifold had 2 little bumps/burrs on the edge that I found and I lightly hit them with a file to remove the burrs.

Torque the bolts to the correct spec and believe the number I had was 34 foot Pounds. So following the torque sequence pattern, I took them down to about 20 on the first pass and then again down to 34. I will re-check torque after a few more hot/cold cycles.

That’s about it…HTH someone.

Pic1 = Intake bolts laid out in order and 2 bolt back on right is where it "seemed" to be leaking.
Pic2 = EGR Bosses on back of manifold all cleaned up and studs removed.
Pic3 = Washer used on Oil Pump Drive Plastic housing
Pic4 = You can see the Dowels I made and the height they were at to let the manifold drop on. Any higher than than and the intake wont slip over these studs.

EDIT - Well slap me and call me Stupid. :>) I was just looking at the Intake Bolts in the pic and realize now, I could have just swapped the 2nd and 3rd bolts on the passenger side. That 3rd bolt is about the length I cut the 2nd bolt to.....Doh!! Of course I notice that now :>)
 

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SSSSSLLaaaaaaaaaaaap.. cwm3 That's just a wake up. I like and respect you too much to call you stupid. I've been following, even though I don't have an LT.
Glad it's done and hope it's stay good for more enjoyment.

Mark: Snowman-33
 

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I put the intake manifold on my BBC by using a pole pivoted on the opposite wheelhouse and was tied to the manifold. I lifted it with one hand on the side I was standing on, positioned it over the engine with the other, and lowered it into place. Nothing moved, and I did not disturb the silicone on the end rails. Nothing to remove. Just put the bolts in, and tightened them. I did glue the manifold gaskets to the heads.

If you need the screws to guide you, you can use long set screws with Allen recesses. No need to cut bolts, or slots in the bolts. I tried this with my BBC, and the set screws interfered with the manifold while lowering it. That is why I tried the pole and string method. It turned out to be so easy, that I was amazed, and had the manifold in place in about 10 minutes. It took me longer to glue the gaskets, and put the silicone on, than place the manifold.
 

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Discussion Starter #4 (Edited)
I put the intake manifold on my BBC by using a pole pivoted on the opposite wheelhouse and was tied to the manifold. I lifted it with one hand on the side I was standing on, positioned it over the engine with the other, and lowered it into place. Nothing moved, and I did not disturb the silicone on the end rails. Nothing to remove. Just put the bolts in, and tightened them. I did glue the manifold gaskets to the heads.

If you need the screws to guide you, you can use long set screws with Allen recesses. No need to cut bolts, or slots in the bolts. I tried this with my BBC, and the set screws interfered with the manifold while lowering it. That is why I tried the pole and string method. It turned out to be so easy, that I was amazed, and had the manifold in place in about 10 minutes. It took me longer to glue the gaskets, and put the silicone on, than place the manifold.
Dang, you got me lost how you did that. I read that a few times and still can't picture what you are describing :wink2:, sounds easy though.

The sacrificial bolt I had in my "Bucket of Bolts" and cut easy with hacksaw. At the back of the manifold you have to fight with keeping the harness and that metal EGR tube out of the way while you hold up the back end of the manifold as you guide the beast into place. I just eyeballed the manifold over the block and dropped the front of the manifold down til it touched lightly on the dowels. Then just slid the manifold backwards a little (while still holding up the arse end of the manifold) til it dropped onto the 2 dowels up front, then just let the back of the manifold drop into place. It was a little bit of a bitch with the car jacked up at the front while standing on a ladder and leaning over the fender holding that manifold.

The nice thing about the LT1 head gaskets is they have 2 little plastic locating pins on each side that just pop into the head and lock them down. Didn't have to fight with those at all. >:). I used a little dab of Ultrablack on the corners, then snapped in the side gaskets and then the bead along the rails and up the side about an inch and then let it sit for a few minutes before the BIG Drop.

Still trying to figure out what you described....draw me a pic. :nerd:
 

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Pretty easy; put the manifold across the gap between the radiator and FEAD, get a 6 foot wood broomstick, put one end on the right wheelhouse slightly in front of the fuse block, lay it diagonally across the car over the center of the manifold, tie the manifold centered with some strong string running straight across above the center of the manifold, or in an X, over the pole (insert two or four bolts in the manifold to tie to if necessary, 3-6 inch gap between pole and manifold as necessary to allow you to lower it far enough to sit where it is supposed to be). You can now easily lift the manifold with the end of the pole on the driver's side. You can then walk the pole toward the rear of the car, and move the manifold over the engine, pivoting the pole on the right wheelhouse. Since you are not straining to elevate the manifold, you can use your other hand to get it into position to lower it. When you have it in position, lower the end of the pole in your hand until it is in place. Of course you have the gaskets and silicone in place before the final placement of the manifold.

I do not have any pics, nor can I draw the process. My BBC manifold is about 35 lbs. With a 2:1 leverage advantage, and not reaching over the car, I am lifting about 18 lbs. and close in to my body (think; doing an arm curl with an 18 lb. dumbbell). Once I have the slack taken up, I do have to lift the pole about 4 inches before moving the manifold, and lowering it into place. I put a folded towel on the right wheelhouse so I did not lean the pole on anything harshly. I hope the above explains what I did better.
 

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Good to hear your on the "done" side of the job 4Door

...on the temporary bolt/stud for manifold alignment....put them front & rear hole of ONE side of motor, not one on either side. That is why you saw if they stuck up much on either side, because they are angled out, it is awkward getting the manifold to set on them. If on same side of motor front & rear...goes right on and if that side is right the other will be dead nuts also
 

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Good stuff, I also fixed my first intake manifold a few months ago during the past summer.

To add; I was chasing out of range values on the scan tool. Searched for vacuum leaks as well, plugged/replaced a lot of lines during the search. After a while I tried to diagnose the intake manifold since it's obviously important for vacuum, and it has bad reputation. No oil leaked from the front or rear of the intake manifold on the car. Plugging in a vacuum gauge gave normal 'healthy engine' readings. Spraying fluids, and blowing propane all around the intake did not show any change in idle, neither did it change any readings on the scan tool. Decided to go ahead and replace the intake manifold gaskets + sealant anyways, since it causes many other people problems, and it would not hurt at nearly 200k miles. I was also curious.

Some of the intake manifold bolts and fasteners came off without any extra effort. They are the first and only fasteners I have ever removed in any car casually...No doubt the only fasteners that will ever come off with ease on this Northern Illinois 9C1. After the manifold and associates came apart, there was no 'china wall' sealants in good condition remaining since I do not remember any significant removal effort... Used Permatrex 'right stuff' sealant on the front, rear, and towards the edges of both gaskets.

Fuel trims are now in range on the scan tool after the intake manifold fix. But not exactly even yet (banks). Drove the 9C1 to NE Ohio atwice after the IM fix, and got 23-25 MPG on full highway tanks on those trips, which was an improvement on previous roadtrips MPG. I have an exhaust gasket or cracked stock manifold on the passenger side as well. Ugh fuel pump wiring.
 

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this type manifold most use the threaded studs with no head for a perfect alignment no error. I would have had them stick up 1 inch over the manifold . slot is good to remove them since you cut them short .

the best info on this is,,,,,,,,,,,,, the manifold bolt was the coolant leak .. good info on that.. easy fix for others , just pull bolt , clean and apply thread sealant ..
 

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I know why you did this R&R, but didn't see thread on that subject while looking quickly this morning before I dig into things at work.

Did you find the root cause of the coolant puddling up on the front of the intake manifold?
 

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Discussion Starter #10
this type manifold most use the threaded studs with no head for a perfect alignment no error. I would have had them stick up 1 inch over the manifold . slot is good to remove them since you cut them short .

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As I mentioned above, the angle of the bolts going into the heads, prevents you from leaving them to long. If they stick up too far past the manifold, you will not be able to get the manifold to slip over those 2 dowels if they are much longer than that. I kept backing the dowels out until I got to the point where the manifold would not drop on and then just threaded them in a turn or 2.

I know why you did this R&R, but didn't see thread on that subject while looking quickly this morning before I dig into things at work.

Did you find the root cause of the coolant puddling up on the front of the intake manifold?
I have that thread linked in the first post and updated that thread. I know for sure the coolant appeared to be combining out of that 2nd bolt. One I pulled it, it was evident that bolt was wet and the intake and head in that area had coolant there. All I know for SURE is that since bolting it all together it has been dry and holding well. I know it seems impossible to have coolant come out there but that how it looked when testing and disassembly of parts sure confirmed it to me.
 

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Discussion Starter #11
Pretty easy; put the manifold across the gap between the radiator and FEAD, get a 6 foot wood broomstick, put one end on the right wheelhouse slightly in front of the fuse block, lay it diagonally across the car over the center of the manifold, tie the manifold centered with some strong string running straight across above the center of the manifold, or in an X, over the pole (insert two or four bolts in the manifold to tie to if necessary, 3-6 inch gap between pole and manifold as necessary to allow you to lower it far enough to sit where it is supposed to be). You can now easily lift the manifold with the end of the pole on the driver's side. You can then walk the pole toward the rear of the car, and move the manifold over the engine, pivoting the pole on the right wheelhouse. Since you are not straining to elevate the manifold, you can use your other hand to get it into position to lower it. When you have it in position, lower the end of the pole in your hand until it is in place. Of course you have the gaskets and silicone in place before the final placement of the manifold.

I do not have any pics, nor can I draw the process. My BBC manifold is about 35 lbs. With a 2:1 leverage advantage, and not reaching over the car, I am lifting about 18 lbs. and close in to my body (think; doing an arm curl with an 18 lb. dumbbell). Once I have the slack taken up, I do have to lift the pole about 4 inches before moving the manifold, and lowering it into place. I put a folded towel on the right wheelhouse so I did not lean the pole on anything harshly. I hope the above explains what I did better.

I gotcha now. :smile2: For me, I was standing on a small ladder sideways while reaching/leaning over the fender and had to contort my "non slender/non flexible" body into positions it doesn't like to go. >:).
 

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No contortions my way. You can even start a couple of the bolts with your free hand, before you do the final placement. I am all of 5'6" , can only bend my right elbow about 20 deg., and have a torn muscle/tendon in my left shoulder. It was still easy.
 

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I don't consider myself particularly strong...but I've had the manifold off the car twice now and both times I did not have any issues with alignment while putting it down. I got an extra bolt that was longer and cut the head off. I didn't have to slot it as I left more than enough to remove it by hand. Anyway, did a couple of test runs and then put the rtv. Aligned the one bolt hole int he rear and dropped straight down.

I do remove the engine wiring harness and move it out of the way. Some people leave it in place and try to wiggle the manifold between all the wires. This is insanity IMO. It only takes a few extra minutes to unplug everything and lay the whole harness out of the way and it makes it much easier to plop the manifold back down without any problems. YMMV. There's a thousand ways to skin a cat.
 

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The nice thing about the LT1 head gaskets is they have 2 little plastic locating pins on each side that just pop into the head and lock them down. Didn't have to fight with those at all. >:). I used a little dab of Ultrablack on the corners, then snapped in the side gaskets and then the bead along the rails and up the side about an inch and then let it sit for a few minutes before the BIG Drop.

Still trying to figure out what you described....draw me a pic. :nerd:
I used ultrablack all the way across the back and the front surface. Been about 8 months and all is oil leak free. Can't remember where I read to do that but I did my 1st intake on the 94 9C1 back in 2003 and after 15 years no leaks !
 

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I usually just muscle it into place as close as possible. Never worried about it being perfectly aligned as it touched down onto the heads. Although you don't want to have to walk it around a lot, it can be moved around a little in order to align the bolts.

Fool proof way to seal the front and back rails:
  1. Place a 1/4" tall bead of the "Right Stuff" on the front and back
  2. Drop the manifold into place, and align the bolts (Do NOT tighten).
  3. Snug the bolts down just barely tight, do NOT torque yet!
  4. Wait about 30 min. to an hour for the sealant to get semi hard, but not fully cured
  5. Torque the manifold down to spec, in sequence (inside out).
  6. Let it sit overnight to cure.
You're essentially letting the sealant form/become like a gasket before applying the additional compression from torquing it down. Pretty much what the directions say. Have done it this way dozens of times, never had a leak. Only drawback is you need a pry bar to remove it.
 
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