Replace the intake manifold gasket on a Chevy Suburban/Tahoe K1500 with a 5.7L Vortec engine (may work with other models) ...without knowing much about cars
Let me start by saying the I do not know much about cars. My vehicle is a 1997 Chevy Suburban K1500 4x4, with the Vortec 5.7L engine.
NOTE: Clicking on the underlined words in this article will show you the pictures associated with this repair.
According to the majority of
people I've talked to, this specific engine is prone to this type of damage,
either because of bad gasket design, bad formula of Dex-Cool, or both,
or none of the above..
But how do you know that your intake manifold gasket has developed a leak? For the
non-mechanical people among you, this type of leak can be internal,
external, or both at the same time.
External leak:
Coolant seeps through the broken intake manifold gasket to the outside
of the engine. Most of the times this happens where the aluminum intake
manifold sits on the straight portion of the engine block. There is no
actual gasket at that location, but a gasket substitute formed by a bead
of RTV.
If your leak is bad, you will see orange coolant constantly dripping
under your truck, but if you have a tiny leak, you may just smell the
coolant, but not see it, due to it evaporating as it touches the hot
engine block. As the engine cools down you might see a few drops under
your vehicle.
Internal leak:
Coolant seeps through the damaged gasket to the inside of the engine,
mixing with motor oil. If you suspect an internal leak, check your oil
dipstick. If you see that your oil has a milkshake-like consistency and
there is rusty
looking residue inside your oil filler cap, than.. most likely
you are right and you have coolant leaking into the crankcase.
Both internal and external intake manifold gasket leaks have at least
one thing in common:
Coolant disappears mysteriously at first, then it's more and more
obvious. Sometimes you can find the source of the leak right away and
sometimes you don't.. Be patient, run your step-by-step diagnostics, you
will eventually find the exact location of the leak. I did!
In my case, it all started with a small, shiny, wet orange tiny
puddle of coolant on the engine block, just under the thermostat housing.
I did not know what it was, so I asked this forum. Experienced forum
veterans and people who had the very same problem before, told me right
away that it was probably an intake manifold gasket leak. The more I
looked at it and the more research I did on the Internet (what would I
do without this most important tool in my life?!?), the more I
understood about the intake manifold gasket issue. One month ago I
didn't even know the difference between an intake manifold gasket and an
o-ring...
Later in the same week, at hints from this forum, I discovered the
residue that looked like
burnt rust inside
my plastic oil cap (plastic doesn't rust, get it??). In the mean
time I have also used a Stant pressure tester for the radiator, and
besides the system not keeping the few Lbs of pressure I was pumping in,
the pressure accelerated the leak by factor 10.
Now I was 100% sure that the diagnose was correct.
What then followed, ..I tried to find a shop here in SW Florida to do it
for cheap. Bad luck, quotes ran from $550 to just over $1,300. My own
research at local auto parts stores showed that the actual gasket set
cost no more than $35, the remainder of the huge repair shop quote was
probably labor.. So I gave up and decided to fix it myself. I didn't
want to do it alone, I know nothing about cars and engines, so I talked
a friend into giving me a helping hand. As recommended by the people in
this forum, I have ordered what seems to be the best gasket set out
there, the 'Fel-Pro MS98000T PermaDryPlus' from RockAuto.com ($59
including shipping, I think). The set not only has the intake manifold
gasket set, but also the gasket for the upper manifold (or plenum), fuel
line o-rings, throttle body gasket, etc. I think there is a total of 8
gaskets in this set, plus a tube of black RTV, needed later when you
install the intake manifold gasket.
Since in the process of replacing the intake manifold gasket you will
expose other hard-to-get-to parts, I decided to also replace some of
these parts, as the distributor gear, cap and rotor. The distributor cap
and rotor cost about $30 at the local store. I purchased the distributor
gear from our local Chevy dealer for $48. As soon as I had all parts and
gaskets that I needed for this repair I started gathering some important
tools:
torque
wrench (the one with the 'click') is an absolute MUST, I bought
an additional tube of 'Permatex sensor-safe Ultra Copper High Temp RTV
Silicone Gasket Maker' from AutoZone and a 'Permatex Medium Strength
Threadlocker Blue' for the bolts (use your favorite brands as you
wish!). A friend even let me borrow his scanner tool (Actron
OBDII CP9135).
The entire repair sounds rather simple: Take off lower intake manifold,
clean everything, apply new gaskets, torque intake manifold down to
specs, done! But in detail it is very time consuming.. There are a bunch
of tubes, lines, hoses and wires in your way. Most of the wires have
colored connectors and you will have to remember their location when it
comes to reassemble everything at the end of your (hopefully successful)
repair. Along the way I took notes, and I mean MANY, very detailed
notes. I am not a mechanic, that means that I have removed many items
from under the hood not even knowing their names. So I used a lot of
simple drawings to describe these items in relation to the ones I
already knew (I knew just a few before this repair, but I've learned as
I deepened into this job). For example I've learned that the 'device
right of the thermostat' is called an 'EGR Valve' when I was at AutoZone
trying to get a gasket for it, with this 'device' in a Ziploc bag.. :) I
also took many digital pictures, sometimes 4-5 of each step, depending
on how difficult it would seem to put everything back together (i.e.
distributor).
After a long weekend of planning, digesting much needed advice and
reading a lot of other people's stories about successes and failures
from the Internet and trying to convince my wife that 'I really know
what I'm doing!' (I lied to her when I told her that, but she also
lied to me when she said she believed me), I finally started!
Unfortunately, the dad of the friend who wanted to help me passed away
just two days before starting this repair, so I had to do it 100% all by
myself :(
There I was, looking at a
dirty engine
that leaks a lot of coolant inside and out.. Here is how I did
it and this is MY sequence, you might do it a different way, it's up to
you. Also note that I have skipped minor steps, like removing cables,
hoses, connectors, etc.:
1. Disconnect battery (first the negative, then the red
positive).
2. Drain your coolant (there is a petcock on the lower driver
side of the radiator).
3. Remove Vortec cover.
4. Remove thermostat cover and hose and push out of the way
(right side).
5. Undo and move throttle and cruise control cables out of the
way.
6.
Remove A/C compressor from its bracket and flip it belly up to the left
(passenger) side. Be careful with those A/C lines! Please note that
'left' and 'right' are the directions as I see them facing the engine
from the bumper side.
7. Disconnect and mark, label, strap together, put in Ziploc bags
(or whatever works for you) all cables, tubes, hoses and electrical
connectors from sensors and other devices.
8. Disconnect all brackets and everything that is either in your
way, or that won't come off with the intake manifold. When putting
everything back together you will need to drop the aluminum intake
manifold back onto the block possibly in one try, straight down,
otherwise you will smear the RTV all over the place and your gasket will
not hold seal and the whole thing will have to be redone.
9. Disconnect throttle body, EGR valve.
10. Disconnect quick disconnect heater hose (be careful, it might
break!).
11. This step is an absolute MUST: Mark the position of the
distributor any way you want, but you need to know the
EXACT
position/angle of the distributor cap in relation to the engine (or to
the firewall), then after you open the cap you need to mark the
EXACT
position of the rotor in relation to the distributor housing. I
really took my time in doing this, because I didn't want to mess up like
many did before me.
12. Mark all cables leading to the distributor.
13. Remove distributor.
14. Depressurize fuel lines (valve looks like a tire valve).
15. Disconnect fuel lines (disconnect firewall side first, then
disconnect from plenum).
16. Unscrew bolts holding long black bracket on firewall side and
left of the plastic plenum, then bend it over towards the firewall.
17. Try to use rubber bands and bungee cords to tie the cables
and hoses away from your work space. Later you will need as much freedom
to move around as possible!
18. Remove serpentine belt out of the way.
19. Remove 3 bolts and one nut (the one on the stud) from the
front of the A/C bracket. None of these bolts are covered by the power
steering pump pulley! There are two more (one nut, one bolt) at the
bottom of the bracket. If I remember right, you will have to remove the
bolt and just loosen the nut to
slide
the entire A/C bracket (along with the power steering pump AS A UNIT!)
forward as much as you need. NOTE: There were a lot of questions
on this on the Internet and here is the answer again: There is a total
of 6 nuts and bolts: 3 bolts and 1 nut in front of the A/C bracket, 1
nut and 1 bolt at the bottom of the bracket. If you did this right, the
bracket will slide towards the bumper like a dream. There is absolutely
no need to disconnect the power steering pump pulley. As opposed to many
people saying that after disconnecting the 4 front bolts you are able to
pry
the whole bracket as much as you need.. I must say this is
wrong. Prying only gives you a maximum of about 1/2", while using the
above procedure gave me a lot more than that and exposed the corner bolt
of the intake manifold that was hidden right below/behind the A/C
bracket. Remember, when you drop the manifold back in place on the block
you will need every little 1/10" you can get!
20.
Remove
left (passenger side) valve cover. Many people say not to remove
any valve covers for this procedure, but I did anyway, plus there is a
nice brand new, blue gasket in the Fel-Pro set and I like the color blue
:)
On a more serious note, I really think that it's easier to do this job
when the left valve cover is being removed.
21. Remove the 8 bolts holding the lower aluminum intake
manifold. You will have to use the same bolts in the same holes, so the
method I used was to stick the bolts in holes I made in a rectangular
cardboard box
that resembles the shape of the engine. I used the very same box to
stick the bolts for the plenum as well (that later).
22.
Remove
intake manifold from engine. Set it on rags, be careful not to
scratch it or drop, it isn't cheap.. and to untrained people like me
it's heavy!
23. Immediately stick fresh clean rags inside the lifter valley
(yes, I've learned what the 'lifter valley' is from the Internet) to
suck all the crap out of it and to prevent any junk from entering any
holes.
On top of the rags I put some white plastic bags and also covered all
ports.
24. Now the toughest job from all: CLEAN, CLEAN, CLEAN! You need
to clean everything until it is
shiny and
spotless! Take all gasket residues from the intake manifold and
engine block, use carb cleaner or similar cleaner to
clean the aluminum intake manifold. Before cleaning, I removed
the plenum from the lower intake manifold and cleaned it until it looked
like new, because I wanted to replace all gaskets in the Fel-Pro set,
but if you want to replace just the intake manifold gasket you don't
need to do this. You can also clean the injectors as you wish, or
anything else you think or you know needs cleaned, but be careful not to
break anything in the process of doing it! It took me about 3-4 days
just for the cleaning part of this job, but the result was very clean
parts and hopefully a lower chance that the gaskets will fail due to
dirt attached to intake manifold, engine block or other parts. Don't
forget to also clean the bolts. Brush them and use carb cleaner on them
as well.
25. If you planned to change the
distributor
gear and rotor, now is a good time to do it. Don't forget to
mount the new parts the same exact way as the old parts, in the very
same position.
26. To me this next
step was essential, but many of you will not need this: I have heard of
many people who had to redo the entire job because when they dropped the
intake manifold back onto the new gaskets and onto the engine block they
smeared the RTV, thus creating a gap in the seal. Such a mistake could
be fatal to this repair. So what I did was to exercise a little bit this
procedure, without gaskets and without bolts of course. I tried to apply
to intake manifold on the block about 10 times until I knew I had the
entire choreography right.
27. Apply gaskets,
RTV, drop intake manifold. These steps are indeed together, because they
are so close to each other that you just can't do the one, then drink a
beer and start again, you need to do this as quickly as possible, and
once you've started proceed until done!
Step 1: I smeared a small film of RTV on the intake
manifold gasket side that sits on the block, especially around the water
ports and all the lines that I could see on the gasket. It was only a
small, thin layer. Fel-Pro says 'INSTALL DRY' without sealant, but I
took the advice from many others, who said to put a very thin bead of
RTV even on the Fel-Pro gasket.
Step 2: Set gasket on the block, then do the same RTV
smear job on the front side of the gasket.
Step 3: Set a thick bead (1/4" to 1/3") of RTV in between
the left and the right gaskets, in front and rear of the engine, and try
to make the RTV overlap each gasket by about 1/2". Because I had to do
this real quick I did not take any pictures of this. It was after
midnight already, and I was under the impression that the RTV was
getting dry already. Remember, you have about 20-30 minutes until it
starts to harden.. So act quickly!
Step 4: Drop intake manifold onto the new gaskets! You
have to do it right the first time! Remember, drop it straight down,
slowly and you will be fine, but if you smear.. I don't want to go
there, but I've heard some stories....
In order to do this right and perfectly match the holes for the bolts
the very first time, I stuck simple
PaperMate ball
pens inside the bolt holes as guides. I used the upper left and
the lower right hole for this procedure and I cut the pens to a length
of about 2-3". These pens are the cheapo pens you find everywhere. They
are tapered and perfectly fit the bolt holes. You can even twist them
half a spin to be sure they don't 'pop' when you drop the intake
manifold. Be careful not to break the pens while doing this! For me it
worked the first time like a dream. Thank God, because I was so worried
about messing up!!!
28. Now that the
intake manifold sits on the brand new gasket, remove the ball pens (if
you have used any), then insert the bolts after applying some
threadlocker on them. First, tie the bolts with just your hands, then
use the
torque wrench to torque them down to specs in 3 stages.
Depending on your gasket's manufacturer, these stages may have different
specs, but the Fel-Pro set has a little note attached to it that lists
the stages as 50"/Lb-100"/Lb-132"/Lb (11ft/Lb). I did just that. Be
careful not to over-torque!
29. Let everything
cure for about 24 Hrs! Do NOT start the engine under any circumstances!
If you've waited this long, then you can wait just a little longer.. Use
this time to put everything back together in reverse order, to clean
everything before you put it back (I cleaned all brackets, hoses,
cables, etc.).
30. OK, you put the
beast back together.. Now take your wife's car, go buy 5Qt of the
cheapest SAE 5W30 motor oil and change the oil and the filter. It cost
me $7 all together. The coolant that mixed with the oil inside your
engine and all that call for an oil change right now. Thank God we can't
hear the engine cry for an oil change now, because it would YELL at us!
31. Put the coolant
back in!
32. If you put
everything back together the right way, and if you marked your
distributor like I did.. then your car will start right up. Mine did! :)
I was surprised, I thought I was going to have a hard time starting my
Burbie for the first time, but.. no problem at all.. I turned the key
for about 2 seconds the first time. Nothing happened. Waited 5 seconds
and did it again. Still nothing. I started to worry, but by the time I
was just starting to worry, I turned the key one more time and it
started!!!!! One of my friends told me that that's normal, because there
was no fuel in the fuel lines and they had to be flooded again. Ooops,
didn't know about that stuff either :)
Anyhow, the engine ran and I was so surprised that I shut it off right
away. Everybody told me that I would have problems with the distributor,
and because I have never removed one before I was kind of prepared for
this. After a 5 minute break I tried to start it again and it started
right away. Yes!!!!! I let it run until the thermostat opened, then shut
it off and put more coolant in the radiator. Everything seemed normal.
Another 5 minutes later I saw coolant dripping down like I did before
the fix. Oh NO!!! I knew it!!! Stupid me, I must have messed up
something with that gasket.. Darn! I went to bed and had 10 nightmares,
all of them about screwed up intake manifold gaskets.. What a pain!
Next morning I ran the engine again, this time about 20 minutes. Coolant
on the floor again. More and more with every minute. All of a sudden, I
discovered where it came from! It was the heater hose that connects into
the quick disconnect, on the top front left of the intake manifold. It
was leaking like hell, the coolant was going around the quick
disconnect, then to the rear of the engine.. and the leak looked just
like the one I had before the fix, but this time I knew that it wasn't a
gasket. I opened the quick disconnect, cleaned it and changed the
o-ring, then put it back. Now it's ok. Right after that I have
discovered a tiny leak in the heater control valve. I replaced that too
for $17, no sweat, 10 minute job.
After exactly 100 miles I changed the motor oil and the filter again,
and this time I bought new Dex-Cool too. The oil that was just 100 miles
old looked already dirty. If anyone recommends to do this, DO IT! Your
oil asks for it!
I've been driving this truck now for another week. Everything seems
perfect so far. I am totally happy that I have successfully performed my
first ever (and hopefully my last!) intake manifold gasket replacement,
all by myself and that my only helper was the Internet. But what a
helper!!! :)
My Burbie is holding seal so far, it is
clean
and smiles at me. The second oil is now 200 old and looks like new. All
the nasty stuff inside the oil filler cap is gone now and everything
works like a dream. I hope to be able to drive this truck another 130k
miles at least! It was not easy to work inside a garage without A/C in
the very hot and sunny Southern Florida. Temperatures close to 100F felt
like 200F in my garage, and the humidity makes you sweat your guts off..
If you use halogen lights like I did, add 100 more degrees to all that.
But when someone says something about intake manifold gaskets I will say
that I did one myself. I still can't believe that the scanner hasn't
returned any error codes yet.. I was either perfect in the installation
of my distributor, or darn lucky! I am an IT guy, I work with computers
for a living and until a month ago the only thing I knew about cars was
to fill them up with gas and change the oil at Wal-Mart every 3k miles.
So trust me when I say that if I can do it, you can do it!
Good luck with your intake manifold gasket replacement!!!
J, aka Suburban-97
..and below is the 'patient' :)
Are you into boating? Visit my other website! (click)
Do you think that anything on this page needs to be corrected, or is technically inaccurate? Please let me know and I will take care of it. Remember, I am not a car mechanic! I am only sharing my experiences with folks who are thinking of doing the same repair and would like to know what it is like.. I am telling my own story, and I am not giving anyone any technical advice on how to fix things.
Do you have any comments? Email me at: PohoaonotooomoFoLo@oyoaohooooo.ocooom