Time Chain....?

  • Thread starter Thread starter Rogers
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Rogers

I have an SW2 1999 What is the suggested time to replace the chain...

I have a 100,000 Miles (164,000kms).

I just started getting, what seems to be a valve tick? Oil and all other
fluids are still good.

Thanks for the info

Graham
[email protected]
 
Not sure on the timing chain service interval is on that engine. Pretty sure
that it is an interference engine - one with minimal piston to valve
clearance. If you get a slip in the timing chain (due to wear and loose
clearance), the piston will likely crash a valve... major headache.
A valve tap is usually caused by a bad lifter. AFIK that engine uses a
hydraulic lash adjuster which may be getting spongy and in need of
replacement. Tap can also be caused by a sticking valve stem.
 
Thanks for the tips, I will be opening it up this weekend I hope...See if I
can find anything.

Still if anyone know the suggested changed interval, I would like to know...

Thanks.
 
Not sure on the timing chain service interval is on that engine. Pretty sure
that it is an interference engine - one with minimal piston to valve
clearance. If you get a slip in the timing chain (due to wear and loose
clearance), the piston will likely crash a valve... major headache.
A valve tap is usually caused by a bad lifter. AFIK that engine uses a
hydraulic lash adjuster which may be getting spongy and in need of
replacement. Tap can also be caused by a sticking valve stem.
Click to expand...

There is no service interval. The chain is supposed to last the life of the
engine. If it does need to be replaced it will make lots of clattering noise
alerting you to impending doom. Oppie is correct in that it is and interference
engine. If the chain snaps it'll bend the valves.
 
bandit2941 said:
There is no service interval. The chain is supposed to last the life of the
engine. If it does need to be replaced it will make lots of clattering noise
alerting you to impending doom. Oppie is correct in that it is and interference
engine. If the chain snaps it'll bend the valves.
Click to expand...

Proper oil changes should prevent that, among other things...
 
I have a Saturn SW2 1997, I had a click noise at 118,000 km sound like a
valve problem. try this: unplug a spark plug (there is no danger) on
piston #1 listen for the noise, if the noise doesn't change replug #1 and
do the same for #2 etc, if you find one piston where the noise reduce or
desepear it's the pin that hold the piston to the arm that is loose
(sorry my english I am french CA) I had that problem and I remove the
engine from the car and send it to a engine refit center (the oil
consumption problem was solved at the same time).
Hope it's not that problem for your car. the computer was giving me some
code also.
 
I have a Saturn SW2 1997, I had a click noise at 118,000 km sound like a
valve problem. try this: unplug a spark plug (there is no danger) on
piston #1 listen for the noise, if the noise doesn't change replug #1 and
do the same for #2 etc, if you find one piston where the noise reduce or
desepear it's the pin that hold the piston to the arm that is loose
(sorry my english I am french CA) I had that problem and I remove the
engine from the car and send it to a engine refit center (the oil
consumption problem was solved at the same time).
Hope it's not that problem for your car. the computer was giving me some
code also.
Click to expand...

You dont ever remove the spark plug wire unless you "ground" it.
Otherwise you risk damaging the coil(s). The other way of doing this
would be to disconnect a Fuel injectors one at a time. Not really
possible with 60deg motors like the 3.0L however but thats why GM
dealerships have the advantage with their Tech II scantools that can
stop injectors from pulsing. But yeah cutting off a piston one at a time
can pin down a problem.
 
Well At you great suprise it's the saturn mechanic itself in montreal that
did this, my friend is the service director at saturn and he ask one of
his best mechanic to have a look at my car and that's what he did, and my
neighbour and my oncle that are both mecanics and they did it with no
problem. I am not saying that there is no risk, but if I look at what they
did it seem's like the risk is very low. :)
 
Speaking as an electrical engineer and fair mechanic,
removing the wire from a functioning plug does cause excessive high voltage
which can damage the spark coil and more importantly, kill the transistor
that drives the coil. Since the transistor is likely in the ECU, that can be
a big oops!
This is not to say that I have never removed a plug wire from a running
engine either, it is just good to know what the potential damage might be.
The coil drive transistor is actually pretty well protected but having a
plug wire disconnected does cause abnormal stress on the components... and
stuff happens.
 
Speaking as an electrical engineer and fair mechanic,
removing the wire from a functioning plug does cause excessive high voltage
which can damage the spark coil and more importantly, kill the transistor
that drives the coil. Since the transistor is likely in the ECU, that can be
a big oops!
This is not to say that I have never removed a plug wire from a running
engine either, it is just good to know what the potential damage might be.
The coil drive transistor is actually pretty well protected but having a
plug wire disconnected does cause abnormal stress on the components... and
stuff happens.
Click to expand...

You can definitly hurt a coil by pulling a plug wire and not grounding it. But
as long as you keep the wire near the head so the spark jumps into the head,
you should be ok.
 
BANDIT2941 said:
You can definitly hurt a coil by pulling a plug wire and not grounding it.
But
as long as you keep the wire near the head so the spark jumps into the
head,
you should be ok.
Click to expand...

Also remember that the Saturn uses a waste spark ignition system. If you
remove a wire and don't ground it you will actually have two cylinders
misfiring.
 
Also remember that the Saturn uses a waste spark ignition system. If you
remove a wire and don't ground it you will actually have two cylinders
misfiring.
Click to expand...

Thats correct. There are 2 coils. When a coil fires it simply completes the
circuit between the 2 posts. One cylinder will be on compression stroke, the
other will be on exhaust.
 
BANDIT2941 said:
Thats correct. There are 2 coils. When a coil fires it simply completes the
circuit between the 2 posts. One cylinder will be on compression stroke, the
other will be on exhaust.
Click to expand...

What I've done in situations like this is to connect a spark plug to
the disconnected wire and then ground out that spark plug.

Ken
 
I've never seen a busted chain. On the engines I've worked with in the past,
the most likely culprits were the camshaft sprocket (with nylon teeth that
wear) and hydraulic chain tensioner (getting slack due to low oil pressure
or binding). All contribute to a loose chain that will start to skip a tooth
here and there. One tooth off can make a big difference in the way the
engine runs. 10 teeth and you've likely got a bent valve and a dented
piston.
_________________
|
| There is no service interval. The chain is supposed to last the life of
the
| engine. If it does need to be replaced it will make lots of clattering
noise
| alerting you to impending doom. Oppie is correct in that it is and
interference
| engine. If the chain snaps it'll bend the valves.
 
I've never seen a busted chain. On the engines I've worked with in the past,
the most likely culprits were the camshaft sprocket (with nylon teeth that
wear) and hydraulic chain tensioner (getting slack due to low oil pressure
or binding). All contribute to a loose chain that will start to skip a tooth
here and there. One tooth off can make a big difference in the way the
engine runs. 10 teeth and you've likely got a bent valve and a dented
piston.
Click to expand...

Yeah. I don't think I've ever seen a busted chain either. Usually the chain
stretches with age and the tensioner stops tightening it up leaving slack in
it, which lets it skip a tooth. It is interesting how much difference one tooth
can make.
 
bandit2941 said:
Yeah. I don't think I've ever seen a busted chain either. Usually the chain
stretches with age and the tensioner stops tightening it up leaving slack in
it, which lets it skip a tooth. It is interesting how much difference one tooth
can make.
Click to expand...

Engine timing is such a precise thing. This is why I will never trust a
"belt" for keeping it in time.
 
how do you know if a car has a belt or a chain? i mean like on the new
cars.
 
Why not? Timing belts usually have a Kevlar core and are stronger than steel
belts.
 
Steel "belts"? Yeah probably so but Kevlar core or not, the outside is
still made up of decomposing rubber and has a life span even when
sitting still. (remember that the belt still makes contact with
unlubricated steel pulleys) Timing Chains that are well lubricated,
along with the valve train, wear out when the rest of the engine wears
out. By then who cares.

boppie@-nospam- said:
Why not? Timing belts usually have a Kevlar core and are stronger than steel
belts.



how do you know if a car has a belt or a chain? i mean like on the new
cars.
Click to expand...

I usually do a google search if its an engine I'm not familiar with. If
you can look at a owners manual it will say in the maintinance portion
if a "timing belt" is due for service.
 
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