98 k1500 sliverado z71 standard cab
This started in February 03. I replaced water pump loosing coolant
irratic temps. Flushed block and radiator;am using dex-cool 70/30.
Still used coolant so I would add from time to time but let reservior
run dry at times. I finally addressed problem this November and
remounted water pump ( small leak), replaced quick disconnect on front
heater hose and gave tune-up plugs,wires,cap,rotor new stat and
radiator cap too. This truck runs great and I have controlled
leak(does not seem to empty reservior like it did, but I still smell
the glycol (maple sryup). I have noticed condensation on oil filler
cap and oxidation behind distributor. Is this an intake gasket leak?
Is there more to it or less I hope? Will sealant tabs be effective?
Have I caught this in time? Or should I dump It? I hate to see it go.
This has been a great used truck for two years, loaded and clean. The
engine gleems; a combo of e.b. and t.l.c.
thanks for reply. the oil is not a milky color yet. truck runs great
as i stated and now still smells but using small amounts of coolant.
maple sryup smell still in the engine compartment. i did check heater
core for leaks and does not have the tell tale signs as fogging
windshild and wet floor. truck has 108k and regular maintainence
schedule is followed, oil every 3000. thought this might be easier
than a new intake gasket kit. I would like to know if this is the next
step and if it is are there any pointers before i start the work
besides the usual drain the coolant, mark the connections ect... also,
I'm wondering if the distributor will have to come out. I have not
referenced the shop manual yet. i hate to distrub the dist.
The distributor must come out. Because it's not necessary on
this engine to "set the timing"...the best way to deal with the
distributor is to first mark the position of the cap in relation
to either the engine or the firewall. The cap has two long ridges
on the top of it that run front to back.....I use these to make
marks that correspond to them on the metal of the firewall.
Then remove the cap and see where the rotor is pointing.
Don't attempt to turn the engine over and get it lined up
with #1.....just mark it's relationship to the firewall/engine
in a way that will be easy for you to remember. Because
the distributor in this model of Vortec v-8 is really nothing
more then a cam sensor.....it's important to get everything
lined back up, but there is no need to "fine tune" the
position of the distributor unless you end up with service
engine light on. If you mark it carefully and reinstall it as
it came out...you wont have any problems.
You also need to remove one valve cover in order to
get the intake manifold out.
You also need to remove the bolts and nuts that hold
the drivers side (a/c and ps pump) bracket and slide
it forward on the long stud that is located on the drivers
side head. This is so that you can access one of the
intake bolts that is underneath that bracket.
Do not attempt to completely get the wiring harness
out of the way....just disconnect everything and then
I usually bungee cord the harness so that it is suspended
above the intake....you slide the intake out from underneath
Do not attempt to remove the fuel lines where they go
into the upper plenum in the middle. Once you have
the distributor out, it's easier to disconnect the lines
right back at the firewall....leaving the fuel lines on the
There is a bracket that holds the wiring harness at the
passenger side rear of the engine. Don't bother trying
to get it completely out of the way. Just unbolt it where
it is secured by the coil and then just move it up and out
of the way. There is no need to attempt to unbolt it where
it is secured to the rear of the head. You will note though
that the bracket has a small tab right where it intersects
the cylinder head/manifold area that sticks forward over
the intake. You need to bend this tab out of the way,
before you re-install the intake, otherwise it can interfere
with the manifold as you are moving it into position.
When you install the manifold you need to be able to
move it into position while keeping slightly above the
gaskets and the RTV at either end....before you lower
it. Otherwise you can wipe the RTV off the ends and
then you end up with a leak after it's all together.
Typical newbie type mistake.
If you are going to change the intake gasket the dist will have to come out.
Since your oil is still clear you should be in the clear. I would suggest
changing it right after you get the leak fixed to be sure. And I wouldn't
drive it until the problem is fixed. The only other thing I can think of is
it could be a heater hose if they happen to run behind the motor or on a big
if a head gasket but it is sounding like the intake gasket.
<notavailable.com (btk)> wrote in message
I would buy one of those leak detect kits, with the fancy light and
glassess, It does oil, water and A/C. I bought mine last year for around
$40.00 found a pesky A/C leak inside the car.
<notavailable.com (btk)> wrote in message
Its common for the 5.7 to leak from the right rear of the intake, coolant
and oil. If you replace the intake gasket you will have to pull the
distributor, just mark the position of the rotor in relation to the
distributor itself before you remove it. Also when you get the intake off
your might want to remove the EGR valve and clear the egr passages as they
are probably full of carbon. When you have it al back together just set the
timing and you'll be all set.
I must have misunderstood you. This is what you said:
It just looks to me like you are advising the poster
to mark the position of the distributor and rotor
and then once you have it all back together (which,
if you install the distributor back into it's original
position, "is" base timing) you need to set the
timing. Which you don't.
No, you don't understand....you cannot check the timing!
What you see with your timing light will mean nothing!
If you actually want to "time" it...ie: get it as close to
base timing as possible, you have to use a scan tool and
check what is called "camshaft retard offset"....which
translates essentially to "base timing". The computer
takes over from there. Remember, on these engines,
what looks like a distributor.....is nothing more then
a camshaft sensor, which can be moved on the v-8's
but not on the 4.3 v-6's.
So for future reference, there is no point in advising folks
with the vortec engines to "check their timing" as it is
I appreciate all of the responses. First, I would like to say that
I'll be tackling this progect in the very near future and I wiil
provide a follow-up report.
I can already see an extra set of hands will come in handy. The
details I got on removal will come in very handy. The timing issue has
always troubled me. I've messed with the point and condenser type and
what a pain in the ass, thus electronic ignition and distributors. I
remember my '86' Ford f250 altough the distributor was electronic the
timing had to be fine tuned with a timing light which I ended up power
timing anyway for the best performance. I appreciate the refresher on
marking the distrbutor and not disturbing the engine. I do belive I
should get it as right on as possible, but I will resource the fine
tuning part just to be sure. I have and old older friend mechanic but
he tends to be a bit vague unless I'm real specific with him. This
help narrow the discussion.
And yes, the oxidation I see is on the back of the engine, rt side.
It only smells when the engine is hot.
I certianly would have disconnted the fuel lines at the manifold
Bungee cord tip on waring harness is great. I woud have and already
have looked at removing completely.
I have had the plenum off and the harness disconnected. Nice to know I
won't have to take of the water pump again as I did my first attempt
to figure this out.
I hate to waste time making newbe mistakes. I sure have made my share
of them and It always costs me double.
I'll save the glasses for the next leak and use the $ for the gasket
kit but nice to know they are available.
Thanks again for all the tips,
On Sun, 30 Nov 2003 02:26:29 GMT, "shiden_kai"
that's a big 10-4 master mech. spec should be under the hood. seems
like electronics would handle. that dist will be a pain to try and
move while timing and running. Not quite out front like the old ford.
I 'd power time it running as i drve down the road. Just stop, pop
the hood and kneel over the shroud. :)
Unfortunately, Mastermech doesn't know what he's talking about
when it comes to "timing" these engines. Please understand that
you simply need to be careful to install the distributor "exactly"
as it came out, ie: both the rotor and the body need to be in the
same relationship to each other and to the engine as when they
If you do this, the timing will be right where it should be, if you
get a "check engine" light coming on after you finish (note, the
engine will still appear to run fine), then somehow you have
changed the "camshaft retard offset", which is a fancy way of
saying that the dist is not at base timing.
Please do not attempt to "power time" it.....this will not work
on these engines. It's also not complicated to return the dist
to it's original position if you just take some time to mark
the cap and it's position to the firewall, and then remove the
cap and mark the rotors position to something before you
remove the distributor body. I've done literally hundreds
of these and have only had the check engine light come on
a couple of times...and that was always due to carelessness
on my part
If you do happen to get the "check engine" light coming on,
(always realizing that it might be something as simple as
you left an electrical component disconnected) you may have
to have a scan tool hooked up so that you can adjust the
base timing (camshaft retard offset).
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