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View Full Version : Replacing the Intake Manifold Gasket - What a Nightmare!


Gregski
04-28-2012, 03:52 PM
Need to replace the Intake Manifold Gasket because I have a coolant leak.

Started at 8:00 am on a lovely Saturday morning, and it is now almost 1:00 pm in the afternoon. I still haven't gotten her off. It is an Air Conditioned car, and that gosh darn AC Compressor bracket serves two purposes, gets in the way of removing the driver side front intake manifold bolt, and by the way holds down the AC compressor, LOL.

I still have a sense of humor but it is fading fast. Lucky for me the wife took the kids in the other car to get hair cuts. So the radio is playing, and I am taking my time to do it right. As of this writing I have penciled down a list of 37 thingies I unbolted or unplugged, or disconnected, or removed, you get the idea. But I believe in order to get the AC compressor bracket out of the way I need to pull the power steering pulley off, and for that I need a super duper special puller. So off to NAPA I go, then maybe to AutoZone.

thanks for reading and wish me luck
California Greg

1997 Chevy Tahoe 5.7L 4WD 4 door (cause yes it makes a diff when buying parts, ask me how I know, LOL)

Gregski
04-28-2012, 07:52 PM
with the power steering pulley off I was able to remove the remaining 4 bolts and free the dreaded AC compressor bracket, here are some pictures

Gregski
04-28-2012, 08:02 PM
well not exactly, at approximately 3:40 PM the intake manifolds (technically the upper black plastic one, and the lower silver aluminumuninum one) were off, here are some pictures, please note the super clever use of the dozen egg carton for the eight intake manifold bolts, I'm sure you could use a 18 egg carton, and no you don't have to use a brown egg one like I did, I'm just sayin'

Gregski
04-28-2012, 08:15 PM
just some pictures for you of what the under side of the lower intake manifold looks like of a 97 Chebby Tahoe, of note are the two blank openings where the rear water passages would be (top picture right side and or the bottom picture), I thought I read somewhere on the forum, that coolant leaks are common from the rear of the intake manifold do to gasket failure around these water passages, well... there are no water passages there, at least not on mine

Gregski
04-28-2012, 08:23 PM
It would be easy to blame the passenger side front gasket failure as the culprit, but I'm too old to go for the obvious stuff, plus I saw some gasket sealant sticking out from the front middle of the valley pan, you know where there is no gasket just a bead of silicone, so maybe it leaked from there, maybe from both places, heck maybe from the rear who knows, it will be replaced soon, and that's all I care about

Gregski
04-28-2012, 08:27 PM
please feel free to comment, I am not an expert and this is not "my" thread, I am sharing this hoping to help somebody out, if you see me doing something bonehead, please let me know how to correct it, I am here to learn, or say something to make us laugh that always works too

tonymac617
04-29-2012, 03:20 AM
Looks like your tackling this job with good spirits, but I must laugh that GM made these gaskets to fail so that they can repair them and make more money, however, they didnt count on the fact that people just ignored the fact that their coolant overflow tanks were somehow emptying, which implied to just add more...then that dreaded lower end knock. Uggggggg! Now a new engine is needed. Yay for plastic plastic gaskets in hot engines. lol Allot of their engines had gasket issues. Nothing ever recalled, but Bulletins went out and on some, the gaskets went from that plastic composite crap they were using to allumium like the 3.8 3800 motors.

Gregski
04-29-2012, 09:21 AM
Yup! I'm still trying to get over the plastic upper intake manifold on essentially what is a Chevy truck. Like a rock my @ss!

lesterl
04-29-2012, 03:07 PM
There was a Class Action Lawsuit on the LIM leaks, google it.

There are rear water passages, in the heads, not the intake IIRC.....

The engines 96-03 all fit into the class action AFAIK. 3.1l, 3.4l, 4.3l, 5.0l, 5.7l Good luck. BTW the Class Action was to reimburse people for repairs they paid to have done (thru a mechanic?)...

Gregski
04-29-2012, 11:02 PM
I'm an idiot I forgot to mark the distributor before pulling it now the car won't start. Please help. I found cylinder one at the top of it's compression stroke aligned with the timing marks on the vibration damper on the front of the crankshaft. I also did my best to have the distributor rotor point at the number one plug wire, had to finagle the notch in the oil pump shaft a bit to get them to align. Not sure how much to wiggle the distributor clockwise / counterclockwise to get her to start. Please help me get this egg off my face.

lesterl
04-30-2012, 05:47 PM
IIRC you point the rotor at #6 tower? Maybe I am thinking 4.3l? I am pretty shure when #1 TDC Compression you dont point rotor there.

lesterl
04-30-2012, 05:49 PM
6.When the distributor is fully seated, the rotor segment should be aligned with the pointer cast in the distributor base. The pointer will have a "6" or "8" cast into it indicating a 6 or 8-cylinder engine. If the rotor segment is not within a few degrees of the pointer, the distributor gear may be off a tooth or more. If this is the case repeat the process until the rotor aligns with the pointer.

-From www.autozone.com repair guide.

(of course this is after finding TDC Compression.)

Gregski
04-30-2012, 06:22 PM
thank you all for trying to help, the following article seems helpful

http://autorepair.about.com/library/a/1a/bl340a.htm

http://z.about.com/d/autorepair/1/0/A/v/84852785.gif

Align white paint mark on the bottom stem of the distributor, and the pre-drilled indent hole in the bottom of the gear (3).

With the gear in this position, the rotor segment should be positioned as shown for a V6 engine (1) or V8 engine (2).

lesterl
04-30-2012, 06:24 PM
I've always heard of the stamped 8 or 6 alignment.... but did it work?

Gregski
05-01-2012, 12:25 AM
I've always heard of the stamped 8 or 6 alignment.... but did it work?

Yup she's running again, the #8 makes the rotor point to approximately 5 o'clock if you were standing in front of the car looking straight down at the distributor. But you must realize that, that's not how you drop the dizzy in, since the gear is twisted you have to start with the rotor a bit counterclockwise from the 5 o'clock position, and then as she drops down she turns and falls into her happy resting place. Of course it is easy once you know how. Scratch that there ain't anything easy about it, LOL, it's just trial and error.

One problem was that I could not see the mark on the distributor shaft that is supposed to line up with the dimple on the bottom tip of the shaft. I had to take a paper towel and wipe off all the oil off the shaft to finally see it. It is faint and approximately 2 inches above the dimple, no not the hole that is one inch above the dimple, it is further up on the shaft.

I also finally went to AutoZone and rented the GM oil pump primer tool. It is worth every penny especially since you get to return it and get your $30 bucks back. I just couldn't turn the oil pump shaft with a long flat screw driver to save my life to get it to align right to allow the distributor to drop that final 1/4 inch.

Gregski
05-01-2012, 01:18 AM
here are some more pics of the job, I would call difficult but not complicated.

I sum this repair up as difficult but not complicated, if that makes any sense. It is difficult because there are many steps to follow, but essentially you are taking things apart and hoping to put them back together in the exact same way. There is no troubleshooting and or testing that would make this job complicated in my opinion, unless you forget to mark the distributor, LOL like me.

I use WD40 to soften up the gunked up old gasket. It makes scraping it off much easier and keeps the debris from flying all over the place. Afterwords I wipe off the surface the best I can, and then shoot it with some carb cleaner to dry it out and remove any oils. The towels catch any overspray. I use a ton of paper towels, as soon as a towel gets a bit dirty I toss it, and reach for a new one so I don't recontaminate the area I am cleaning.

Gregski
05-01-2012, 01:34 AM
I can't stand putting back on dirty parts, so I always spend a lot of time on cleaning them, and it is very hard, after wasting an entire airosole can of engine degreaser on the stupid AC compressor bracket with minimal results, I deiced to resort to my old bag of tricks for the intake manifold, are you guys sitting down, good... I used regular liquid dish soap, a bucket of hot water, a long bristle brush, a green 50 foot long garden hose, and some elbow grease, I taped off all the plugs with green "Frog" tape you use when you paint a room (from Home Depot) it's like blue tape but better supposedly, no I didn't blast the intake with the garden hose I held it on it's side and barely drizzled some water here and there to get the soap residue off

I don't clean for looks, I clean when it is practical, I couldn't reassembly the engine and have it look like in the before shots since then I wouldn't know if my new gasket was water/oil tight, now that the engine block is somewhat clean I should be able to tell if anything is leaking

by the way the stem of the oil filler is already leaking a bit on the driver side valve cover, what a silly design

Gregski
05-01-2012, 01:41 AM
anytime I do a repair there are some casualties, if it's not the wife's towel set from the guest bathroom than for sure it is some busted knuckles, but in this case it's the poor PCV rubber elbow, man no matter how careful you are this stuff just gets brittle, and this guy had a long 15 year life, a quick trip to the local NAPA auto parts store and $5.05 later we were back in business

guess what the car would rev up and down without this little silly thing, I had no idea the valve it mates with the valve cover was that important

lesterl
05-01-2012, 09:36 PM
The PCV sucks the vapors out of the crankcase and burns them in the fuel/air mix. There is a decent amount of vacume behind it and if cracks arise it will act up on ya.

RandyatBBY
07-29-2012, 08:35 PM
I am in the middle of the same project your thread is helping. I am stuck on trying to drain the cooling system. I was told that the bolt on the bottom of the block if removed will drain the system but I can not get a good grip in it. I will get a picture of it and post it.

RandyatBBY
07-29-2012, 10:14 PM
Hear is a picture looking up from below drivers side. It is hard to see this is to get a general idea.
http://img854.imageshack.us/img854/1153/picture011tn.jpg (http://imageshack.us/photo/my-images/854/picture011tn.jpg/)
this is a close up of the plug
http://imageshack.us/a/img26/3620/picture009a.jpg (http://imageshack.us/photo/my-images/26/picture009a.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

RandyatBBY
07-29-2012, 10:15 PM
It might be easier if I remove the brace. I am going to try that now.

bubinga
08-17-2012, 10:08 PM
I just want to say thanks ,Gregski, for posting this, I have an FSM but this helps
I have to fix mine got a leak
Question: do you need to remove valve covers or not ??

RandyatBBY
08-18-2012, 12:38 AM
I just want to say thanks ,Gregski, for posting this, I have an FSM but this helps
I have to fix mine got a leak
Question: do you need to remove valve covers or not ??

Yes you do need to remove one valve coverI had the most trouble getting the fan off. I ended up getting two longer bolts to hold the pulley.

bubinga
08-18-2012, 01:27 AM
Since I am going to be doing this ,I figured I would add info while in the process.
This is mainly to give Torque Specs

Lower Intake Manifold Bolt ,Torque Specs & Tightening Sequence ,for 99/5.7

First Pass in Sequence
3 Nm
27 lb in

Second Pass in Sequence
12 Nm
106 lb in

Final Pass in Sequence
15 Nm
11 lb ft

6133
------------------------------------------------------------------------

Upper Intake Manifold Stud
First Pass 44 in.lb
Final Pass 89 in.lb

6137

-----------------------------------------------------------------------
Install the power steering bracket onto the stud.
Install the nut onto the stud finger tight.
Install the three bolts finger tight.
Install the two nuts to the back of the power steering pump. Tighten
Tighten the nuts and the bolts to 41 Nm (30 lb ft).
---------------------------------------------------------------

Install the valve rocker arm cover washers and bolts. Tighten
Tighten the bolts to 12 Nm (106 lb in).
-------------------------------------------------------
Install the upper intake manifold studs (1). Tighten
Tighten the upper intake manifold studs on the first pass to 5 Nm (44 lb in).
Tighten the upper intake manifold studs on the second pass to 10 Nm (89 lb in).

If reusing the fasteners, apply threadlock GM P/N United States 12345382, GM P/N Canada 10953489, or equivalent, to the threads of the upper intake manifold attaching studs .
--------------------------------------------------------------------------------
Install the engine coolant thermostat.
Install the water outlet.
Install the water outlet studs. Tighten
Tighten the water outlet studs to 25 Nm (18 lb ft).
---------------------------------------------------------------
Install a NEW throttle body gasket into the groove in the upper intake manifold.
Install the throttle body onto the upper intake manifold.
If reusing the fasteners, apply threadlock GM P/N United States 12345382, GM P/N Canada 10953489, or equivalent, to the threads of the throttle body attaching studs.
Install the throttle body attaching studs. Tighten
Tighten the throttle body attaching studs to 9 Nm (80 lb in).

------------------------------------------------------------------------------
Install the accelerator control bracket, the bolt, and the nut. Tighten
Tighten the accelerator control bracket bolt and the nut to 12 Nm (106 lb in).
-----------------------------------------------------------------------------

Install the distributor mounting clamp bolt. Tighten
Tighten the distributor clamp bolt to 25 Nm (18 lb ft).
---------------------------------------------------------------------

Tighten distributor cap screws.to 2.4 Nm (21 lb in).

bubinga
08-23-2012, 05:22 AM
Yes you do need to remove one valve coverI had the most trouble getting the fan off. I ended up getting two longer bolts to hold the pulley.

Keep in mind I haven't done this yet but , why is it necessary to remove the fan??

RandyatBBY
08-23-2012, 03:01 PM
Keep in mind I haven't done this yet but , why is it necessary to remove the fan??

I am assuming you have original water pump like I did and need to replace it.

It is a good time with all the stuff out of the way good insurance and drains the block of antifreeze necessary to remove the intake.

COLVTAHOE
10-07-2012, 03:42 AM
I'm new as of about 20 minutes ago, and I can admit I NEED HELP!!! haha. I too have the same leak and it seems to be coming from the back. After investigating further, I notice that it could be anywhere along that whole side.

I thank you all for the VERY useful information. I was dreading having to pull the entire engine. I am 99.9% sure this is the cause of my leak, as well.

Can anyone please recommend any good service manuals for this model. More specifically the '99 Tahoe. I understand they are the same for the most part. But I need every advantage I can get at this point. I am in a race to beat the freezing temperatures of late fall/winter.

Also, can anyone provide an overall cost I am looking at to repair this? I am pretty savvy with fixing my truck (thanks to my old man), so thankfully I can perform the labor myself. Can anyone provide links to the requires gaskets, recommend any upgrades or coupon codes for websites?

One thing to bare in mind, i'm a broke and back in college student working full time for little pay. Every little discount (but quality matters) will help me out. As well as anymore pictures and possible walk-through to save myself some time.

Thank you advance gentleman, and ?ladies? perhaps? Your help to this point has been tremendous and for that alone I thank you already.

bubinga
11-07-2012, 04:10 AM
Don;t know if U repaird this yet, I haven't been here in awhile.
I have a 99 Hoe

This is a manual I bought on DVD,from ebay for 25 bucks, it has the same info as the 4, big paper books and more.
Works GREAT,Great seller
Every one should have one of these, you can not go wrong for the price
The seller has many models and makes.

CHEVROLET TAHOE FACTORY SERVICE REPAIR MANUAL 1998 1999 2000 98 99 00

http://www.ebay.com/itm/CHEVROLET-TA...item337c131b4f

Cost me about 75 bucks,for parts, from Advance Auto ,search on line for Advance Auto discount codes,buy on line pick up at store,or have parts shipped.
Or get parts from Amazon,

http://api.viglink.com/api/click?format=go&key=3deb13e6de5efc47d7afda436f2a8ff0&loc=http%3A%2F%2Fwww.tahoeyukonforum.com%2Fforum%2 Fshowthread.php%3Ft%3D42043%26page%3D7&v=1&libid=1352278654458&out=http%3A%2F%2Fwww.amazon.com%2FFel-Pro-MS98000T-Manifold-Gasket-Set%2Fdp%2FB000CH0C0Y%2F&ref=http%3A%2F%2Fwww.tahoeyukonforum.com%2Fforum%2 Fsubscription.php%3Fdo%3Dviewsubscription%26pp%3D1 5%26folderid%3D0%26sort%3Dlastpost%26order%3Ddesc&title=Engine%20setting%20for%20years%2C%20what's%2 0the%20best%20way%20to%20prepare%20for%20start%20u p%3F%20-%20Page%207%20-%20Chevy%20Tahoe%20Forum%20%7C%20GMC%20Yukon%20For um%20%7C%20Tahoe%20Z71%20%7C%20Cadillac%20Escalade %20-%20Tahoe%20Yukon%20Forum&txt=http%3A%2F%2Fwww.amazon.com%2FFel-Pro-MS9800...dp%2FB000CH0C0Y%2F&jsonp=vglnk_jsonp_13522789861317

http://api.viglink.com/api/click?format=go&key=3deb13e6de5efc47d7afda436f2a8ff0&loc=http%3A%2F%2Fwww.tahoeyukonforum.com%2Fforum%2 Fshowthread.php%3Ft%3D42043%26page%3D7&v=1&libid=1352278654458&out=http%3A%2F%2Fwww.amazon.com%2FFel-Pro-ES72224-Engine-Intake-Manifold%2Fdp%2FB0039SOMUE&ref=http%3A%2F%2Fwww.tahoeyukonforum.com%2Fforum%2 Fsubscription.php%3Fdo%3Dviewsubscription%26pp%3D1 5%26folderid%3D0%26sort%3Dlastpost%26order%3Ddesc&title=Engine%20setting%20for%20years%2C%20what's%2 0the%20best%20way%20to%20prepare%20for%20start%20u p%3F%20-%20Page%207%20-%20Chevy%20Tahoe%20Forum%20%7C%20GMC%20Yukon%20For um%20%7C%20Tahoe%20Z71%20%7C%20Cadillac%20Escalade %20-%20Tahoe%20Yukon%20Forum&txt=http%3A%2F%2Fwww.amazon.com%2FFel-Pro-ES72224-Engine-Intake-Manifold%2Fdp%2FB0039SOMUE&jsonp=vglnk_jsonp_13522790096578

I also got the other valve cover gasket.
http://www.amazon.com/Fel-Pro-VS50293R-Valve-Cover-Set/dp/B000C2GIGQ/ref=pd_sim_auto_3

sphillips
12-16-2012, 09:35 AM
Just finished my intake manifold project yesterday, all is well. Used all of the gaskets in the FelPro set, except for two small o-rings, which I couldnt figure out where they go. They werent the fuel lines going to the upper induction manifold, too small. Time consuming but very doable.

socalTizoe
07-23-2013, 02:43 PM
I scoured the web for details on how to do this job, including this thread, which helped a lot at least to get the courage to dive in.. I'm not mechanic and I've never dug this deep into the engine, but i had all the tools i needed from repairs done in the past (alternator, water pump, etc..) and i agree.. it's not difficult but there's a lot to remove.. labeling everything was a huge help. and there are a lot of videos and pictures out there, this post helped a lot:

http://www.d-tips.com/general/articles/article.aspx?id=11

My Symptoms:
I was missing coolant but had no leaks.. i found coolant in my oil during the last oil change, radiator did not seem to have any oil discoloration (recent flush and no oil in there either).. i had been losing coolant noticeably for about 3k miles.. I developed a knock on startup which went away after about 2 minutes of warm up. I thought initially it was my head gasket, found out the stock manifold gaskets are junk

Just to help out anyone attempting this repair, here are some notes from my adventure.. I have a '99 tahoe LT 4x4 103k

-You dont need to remove the alternator

-I did not remove the upper intake

-You can slide the AC compressor bracket forward without removing the Power Steering pulley, there is a screw about 1 inch to the right and about 6 inches back from the lower left bracket screw, i think its 14mm.. but i was able to remove it with an extension on the ratchet. wasnt hard, but was hidden

-I could not remove the fan, but removed the upper shroud.. it required a wrench bigger than anything i had, i've also seen some serious struggles removing it.. so i just removed the screws to give me some space (after if realized that the screws didnt release the fan), this just helped get to the AC screws really.. so its not necessary

-I removed both valve covers and replaced the gaskets since I was there.. found some "milkshake" froth in one of them and cleaned them up, this made getting the manifold out easier as well

-I marked each connector i disconnected with a whiteout marker

-you dont need to remove the rear wiring harness (as noted in the article above) which is on the passenger side of the engine, you can bend it back (carefully) 1st, but it will need to be loosened in order to get the manifold back on cleanly.. there was a ground wire attached on mine (it broke and i'm not sure what it does, thoughts?)

-clean the surfaces very well, i applied a little bit of "Grey" to the ports on the manifold which were corroded, and around the ports which had "pitting" on the engine, i've read different feelings on that subject.. but i went for it

-Pour a bunch of oil down the valley after the cleaning and replace the oil before the 1st start

-flushed coolant by removing the lower hose after the reassembly

-removed the oil after reassembly before the 1st start

-drove it lightly about 50 miles and performed engine flush and replaced oil and filter (30% lucas to be safe)

-so far so good, I dont seem to be losing coolant and the truck runs just like it did before the change (very nicely)

so thanks for posting this info, and hopefully someone will find this additional info helpful. I was quoted $800 in labor for the job, and seeing I dont have $800 lying around, the repair has been well worth it..

:smokin:

RandyatBBY
07-23-2013, 04:01 PM
I scoured the web for details on how to do this job, including this thread, which helped a lot at least to get the courage to dive in.. I'm not mechanic and I've never dug this deep into the engine, but i had all the tools i needed from repairs done in the past (alternator, water pump, etc..) and i agree.. it's not difficult but there's a lot to remove.. labeling everything was a huge help. and there are a lot of videos and pictures out there, this post helped a lot:

http://www.d-tips.com/general/articles/article.aspx?id=11

My Symptoms:
I was missing coolant but had no leaks.. i found coolant in my oil during the last oil change, radiator did not seem to have any oil discoloration (recent flush and no oil in there either).. i had been losing coolant noticeably for about 3k miles.. I developed a knock on startup which went away after about 2 minutes of warm up. I thought initially it was my head gasket, found out the stock manifold gaskets are junk

Just to help out anyone attempting this repair, here are some notes from my adventure.. I have a '99 tahoe LT 4x4 103k

-You dont need to remove the alternator

-I did not remove the upper intake

-You can slide the AC compressor bracket forward without removing the Power Steering pulley, there is a screw about 1 inch to the right and about 6 inches back from the lower left bracket screw, i think its 14mm.. but i was able to remove it with an extension on the ratchet. wasnt hard, but was hidden

-I could not remove the fan, but removed the upper shroud.. it required a wrench bigger than anything i had, i've also seen some serious struggles removing it.. so i just removed the screws to give me some space (after if realized that the screws didnt release the fan), this just helped get to the AC screws really.. so its not necessary

-I removed both valve covers and replaced the gaskets since I was there.. found some "milkshake" froth in one of them and cleaned them up, this made getting the manifold out easier as well

-I marked each connector i disconnected with a whiteout marker

-you dont need to remove the rear wiring harness (as noted in the article above) which is on the passenger side of the engine, you can bend it back (carefully) 1st, but it will need to be loosened in order to get the manifold back on cleanly.. there was a ground wire attached on mine (it broke and i'm not sure what it does, thoughts?)

-clean the surfaces very well, i applied a little bit of "Grey" to the ports on the manifold which were corroded, and around the ports which had "pitting" on the engine, i've read different feelings on that subject.. but i went for it

-Pour a bunch of oil down the valley after the cleaning and replace the oil before the 1st start

-flushed coolant by removing the lower hose after the reassembly

-removed the oil after reassembly before the 1st start

-drove it lightly about 50 miles and performed engine flush and replaced oil and filter (30% lucas to be safe)

-so far so good, I dont seem to be losing coolant and the truck runs just like it did before the change (very nicely)

so thanks for posting this info, and hopefully someone will find this additional info helpful. I was quoted $800 in labor for the job, and seeing I dont have $800 lying around, the repair has been well worth it..

:smokin:

It could have been a head gasket leak from your symptoms did you do a compression check?

socalTizoe
07-23-2013, 05:28 PM
I did not do a compression check because i dont have the tools, but the manifold gasket was destroyed which gave me reason to believe that it was the culprit.. if I continue to lose coolant, i will assume it's the head gasket and take it to the mechanic when i have the funds.. if i dont lose anymore coolant i'll assume the problem is fixed.. thanks for the reply..

lllloyd1
09-28-2013, 11:52 AM
I did this same job a year ago wish I had read your post, I had to get it timed after I was done. My marks came off and as you know that was that. Also now I have to either replace the Lower or figure out how to re-tap the coolant quick disconnect hole. And that darn one screw is a bear to remove. Thanks of all the great info. by the I took pictures of were everything went, a live saver for sure. Have a great day Leonard

miuwu208
11-30-2013, 03:30 PM
I am in the middle of the same project your thread is helping. I am stuck on trying to drain the cooling system. I was told that the bolt on the bottom of the block if removed will drain the system but I can not get a good grip in it. I will get a picture of it and post it.

Loosen the knock sensor under the passenger side and drain the block, works great when doing a full flush also JUST MY .2 CENTS

4x4Blazer
12-05-2013, 08:39 AM
When draining coolant from an engine, I have an old shop vac I use, just suck out the coolant from the radiator at the rad cap neck, then remove t-stat and housing and let it suck out the rest of the coolant from the intake T-stat hole. Works awesome, then no coolant leaks in the lifter valley..

lesterl
12-05-2013, 07:51 PM
Nice....

FD611V
12-12-2013, 10:15 AM
Have '96 Tahoe with the 5.7 V8. I also had a coolant leak at the left front on the intake manifold. It wasn't bad, but it also wasn't good to have coolant leaking into the crankcase, which would start bearing wear. My oil pressure when I bought the Tahoe new the oil pressure at start up would be around 60 psi, and settle at 50psi at hot. With the mileage at 129,500 miles (10/2012 year), my oil pressure was 55psi cold, and settle about 43psi when hot. I knew there was some wear on the crankshaft bearing and decided to take on the task of replacing the manifold intake gasket. I did basic the same as most that tackle this job, and few hours of examine what had to be done....removing all the wires and marking/labeling each one. I didn't remove the powering steering pump, just went under and loosing the bolt and slid the pump forward enough to get to the front left side manifold bolt.
I did something that most probably wouldn't do... remove the distributor. I found it was better to remove the distributor to ease the effort in removing the manifold. But, I did something different, marking the distributor in four places so I wouldn't have any problem when re-installing it, knowing if it did it wrong when installing the distributor, I would have to have the engine scanned.
At the base of the distributor I taken a small chisel and made marks both on the manifold and distributor base. Also when I removed the distributor cap, I made three marks...one with the rotor tip to the distributor housing, another on the opposite side, when you remove the distributor it will rotate some 5 degress counter-clockwise and you have to make another mark on the distributor housing there. When you install the distributor you have to make sure it goes back in the same way it was removed. When I finished all as some listed....filling the radiator, changing the oil, etc. I started the engine... Great!!! no check engine light lit up. The engine ran fine....no leaks appeared. I drove the Tahoe some 20 miles and here it is one year later and no leaks or adding any coolant to the radiator.
All is well.

lesterl
12-12-2013, 11:29 PM
how the he11 would you remove the manifold to do the gaskets without removing the distributor? AFAIK you have to remove it......

laredo1307
12-18-2013, 12:28 PM
Since I've had my Tahoe the last 4yrs I wonder how it never overheated but yet my reservoir was always dry. My leak must be very small. I've also heard the dreading knocking sound (only under load) from time to time but I have to admit that it's not as bad since I replaced my exhaust and did a tune-up. Somehow this is the first time I've stumble upon this issue. I knew there was issues with Dexcool for other reasons but it looks like whoever had the truck before me had replaced the coolant with something else. They may have even done the manifold gasket repair before but I do not see anything in the records that came with the truck. I'm definitely a "wrencher" by nature so I have no problem tackling this project. But, this thread definitely takes all the guessing out of the way on how to go about everything. I now know what my 1st project will be for the new year.

FD611V
01-01-2014, 12:46 PM
This is the information on how I did mind. It shows pictures with all the instruction this person did on his Tahoe 5.7 V-8. I marked my distributor in several places so I could install it the same location. Didn't need to have it scanned.

http://www.market-place.com/intake/intake.htm

Mayhem
07-21-2014, 02:59 PM
I know, old thread, but I just read it. WOW some people took off more than was needed, no wonder they had head aches. I left valve covers on and just loosened the AC bracket enough to clear the intake. Used blue tape to mark everything. 1 to 1, 2 to 2 etc. About a 6 to 8 hour job taking some breaks in there. One trick I did was to use a ratchet strap tie down hooked to the luggage rack to hold the wiring harness out of the way. I did take hood off to let more shop light in, about 10 min work, but offset by being able to see better.