1994 Sierra 1500 stalled in road and won't start

[thinger2]

If the dist is in and lined up with #1 plug wire and not off a tooth.
And using the witness mark you can observe that the dist. is not moving.
And #1 piston is truly at top dead center on the compression stroke.
And both #1 valves are fully closed.
Then you can eliminate timing chain skip.
Im thinking that if all of the above is true and verified, your harmonic balancer is bad.
They are a two piece construction with a solid inner part that goes on the crank and an outer "ring" that has the timing mark on it.
These are seperated by a rubber part that holds them together but is known to fail and makes the outer ring slip in relationship to the crank which makes the timing mark out of sync.
The other possibility is that the key and keyway on the crank snout have sheared off and the balancer is only being held by the bolt.
"StaticTime" the entire assembly.
Make sure the crank bolt isnt strippedor broken and if you try to spin the crank by using that bolt, pull all of the plugs first and go slow.
That bolt can strip the threads out of the crank and it can also break off in the end of the crank

 

[thinger2]

I have more info for those still around.

I didn't get a chance to do a reference mark as I'm slightly unsure how to. Meaning I don't know exactly what this means. Ill re-read that post and see if I can make sense of it.

I Readjusted everything and found TDC and adjusted everything perfectly. Tightened down everything very well.

I noticed the engine sputters when pushing the gas pedal down harder. I was going up the same hill that the truck stall on a month ago and gave me the initial problems and there was a really slow car in front of me. I had to slow down and in order to make it all the way up the hill I had to push the gas down more. (the truck greatly prefers getting momentum going up hills) Well, it almost stalled and started sputtering and jumping up and down in RPM's. It's like something slips loose and goes out of place when pressing the gas too hard. I checked this theory out closer to my house and it kept doing this weird sputtering jumping of rpm's when pushing the gas pedal past 2/3 3/4 down.

I got home and check the markers and it was off again about 4 notches counterclockwise.

I am sorry I didn't do a witness marker yet. I will work on doing that but I thought I would update everyone with this info .

thanks

A "witness mark" is just means to put a mark on two parts so that you can see if those parts have moved in relation to each other.
You can use a screwdriver and scratch a line between the two, you can use a dab of paint whatever.
It just needs to be something you can look at and see noticeable change or not.
There are a couple of basics to consider here.
The first is "static timing"
in other words, the basic mechanical timing of the rotating assembly without it running and without considering ecm input or ignition or anything else.
If the crank turns, does the cam turn the correct amount, if the cam turns, does the distributor turn the correct amount,
If the cam turns do the valves open etc...
Figure that out but dont be surprised if it runs like crap, it will.
Thats when we go to step two.
Teaching the ecm to control timing through the sensor inputs.
And step 3
Have a beer and relax cuz you figured it out.
The TBI can be a pain in the ass untill you get it whipped.
But the only thing more simple than a tbi is riding lawnmower or a vw bug.
And they dont have heaters that work.
One step at a time and you got this and ill help too

 

[simonphelps08]

A "witness mark" is just means to put a mark on two parts so that you can see if those parts have moved in relation to each other.
You can use a screwdriver and scratch a line between the two, you can use a dab of paint whatever.
It just needs to be something you can look at and see noticeable change or not.
There are a couple of basics to consider here.
The first is "static timing"
in other words, the basic mechanical timing of the rotating assembly without it running and without considering ecm input or ignition or anything else.
If the crank turns, does the cam turn the correct amount, if the cam turns, does the distributor turn the correct amount,
If the cam turns do the valves open etc...
Figure that out but dont be surprised if it runs like crap, it will.
Thats when we go to step two.
Teaching the ecm to control timing through the sensor inputs.
And step 3
Have a beer and relax cuz you figured it out.
The TBI can be a pain in the ass untill you get it whipped.
But the only thing more simple than a tbi is riding lawnmower or a vw bug.
And they dont have heaters that work.
One step at a time and you got this and ill help too

I'm a bit overwhelmed and I'm starting to wonder if I got the chops to get the job done. I'll continue to work on this one step at a time and ask questions if I run across any. Thanks for the excessive help.

 

[thinger2]

I'm a bit overwhelmed and I'm starting to wonder if I got the chops to get the job done. I'll continue to work on this one step at a time and ask questions if I run across any. Thanks for the excessive help.

You got this. Just take it one step at a time and you will get it done.
The small block Chevy is the gateway drug to all things mechanical.
Ill bet if you take a poll a lot of the people on this forum started out on the sbc.
And none of us knew a damn thing about them when we started out either.
We all learned from somebody else and thats kinda why we are all here
To pass things along and try to save people from some of the grief.
Trust me, if my ADD brain can eventually figure this **** out you can too!

 

[simonphelps08]

You got this. Just take it one step at a time and you will get it done.
The small block Chevy is the gateway drug to all things mechanical.
Ill bet if you take a poll a lot of the people on this forum started out on the sbc.
And none of us knew a damn thing about them when we started out either.
We all learned from somebody else and thats kinda why we are all here
To pass things along and try to save people from some of the grief.
Trust me, if my ADD brain can eventually figure this **** out you can too!

Thank you, I did some researching and I'm feeling ready. I believe the things I dont understand yet are things I dont actually need to understand.
As you stated above everything seems to line up. All I need to do is make sure #1 valves are closed. Let me type this out and you can let me know if everything I'm about to do sounds right.

1. find TDC again now the everything is out of wack.
2. adjust all the moving parts and get everything lined up TDC .
3. After it's sitting TDC check the valves to make sure they are closed
4. IF valves are closed the problem is the harmonic balancer. (I dont understand why this means it can't be the timing chain but I dont need to understand either)
5. Buy a harmonic balancer (you said this was basically 2 parts. I assume you were just being kind and explaining this to me. I'm stupid so I need to check. I'm only buying one part "harmonic balancer" and you were explaining to me all the components inside this?)
6. Install balancer
7. Crack open drink of choice because it's fixed (this kid will go with Mountain Dew)

Does anyone know off the the top of their head how many lbs to tighten the center bolt back down to when reassembling? I need to do some research to figure out how many pounds to tighten the center bolt back down too.

 

[letitsnow]

If you do need to change the harmonic balancer, I think that you will need a puller like the one that I am using in this picture.

You must be registered for see images attach

I am using this to pull an atv flywheel, but it is a harmonc balancer puller that I purchased from a local auto parts store. It was only $23 here, not sure about there.

 

[thinger2]

The quick way to check the balancer is to stick a long screwdriver or a metal rod in the number 1 plug hole. rest it on the piston and rotate the crank untill you feel the piston get to tdc.
Turn it back and forth a few times untill you get the feel of where tdc is.
Pull all of the plugs when you do this so you arent fighting the compression of the engine and so you dont break the crank bolt
Then take a look at the timing mark on the balancer.
It should be at 0 degrees or really close to it. ( they are not always dead nuts accurate)
If the mark is off, you have a balancer problem.
The balancer consists of the inner hub and the outer ring that are bonded together when they are new.
Over time, that rubber bond can fail and allow the outer ring to slip which causes a misalignment of the timing mark.
As mentioned, you will need a puller to get the balancer off.
You should also use a balancer install tool to put it back on
They look like this

You must be registered for see images attach

This one is Chevy specific.
You can install them without this tool but it is a pain.
You have to be very carefull and dont beat on the outer ring at all.
Dont use the bolt to pull the balancer on. You can break the bolt off in the crank.
And dont bludgeon the thing with a hammer either

 

[simonphelps08]

The quick way to check the balancer is to stick a long screwdriver or a metal rod in the number 1 plug hole. rest it on the piston and rotate the crank untill you feel the piston get to tdc.
Turn it back and forth a few times untill you get the feel of where tdc is.
Pull all of the plugs when you do this so you arent fighting the compression of the engine and so you dont break the crank bolt
Then take a look at the timing mark on the balancer.
It should be at 0 degrees or really close to it. ( they are not always dead nuts accurate)
If the mark is off, you have a balancer problem.
The balancer consists of the inner hub and the outer ring that are bonded together when they are new.
Over time, that rubber bond can fail and allow the outer ring to slip which causes a misalignment of the timing mark.
As mentioned, you will need a puller to get the balancer off.
You should also use a balancer install tool to put it back on
They look like this

You must be registered for see images attach

This one is Chevy specific.
You can install them without this tool but it is a pain.
You have to be very carefull and dont beat on the outer ring at all.
Dont use the bolt to pull the balancer on. You can break the bolt off in the crank.
And dont bludgeon the thing with a hammer either

I know I am asking a lot of questions but I want to make sure I'm confident and sure with what I am about to do. Interestingly enough, One video I watched showed a puller and the other person removed the balancer using a strap wrench with a wrench. I will make sure to get a puller.

As far as checking the piston and top dead center I'm happy you re-stated yourself. From your statements before your most recent comment, I understood to check and see if the valves are closed while at TDC and if the #1 valves are closed then the problem IS the balancer. For some reason your two quotes below are contradictory and I want to be 100% before starting.


"#1 piston is truly at top dead center on the compression stroke.
And both #1 valves are fully closed.
Then you can eliminate timing chain skip.
Im thinking that if all of the above is true and verified, your harmonic balancer is bad"

"take a look at the timing mark on the balancer.
It should be at 0 degrees or really close to it. ( they are not always dead nuts accurate)
If the mark is off, you have a balancer problem."


So what is confusing me is. IF everything DOES line up the balancer is bad or if everything DOESN'T line up it is bad?

 

[thinger2]

Sorry about the phrasing on that.
Those are two associared statements that left out some assumtive details on my part
The very first thing is to physically establish that the piston is at tdc in order to see if the balancer is correct.
That is the part about putting a feeler of some type into the #1 plug hole and finding tdc without referencing the timing mark.
No matter which stroke the piston is on.
TDC of the piston should also be timing mark at zero.
The dampener is keyed onto the crank and the crank is mechanically connected to the rods and thus to the pistons.
The mark will either line up at zero with the piston at tdc.
Which is good
Or the mark will be off with the piston at TDC.
Which means the timing mark itself is not aligned.
Not the crank or the piston, but the outer ring of the balancer.
Do that check first to see if you can eliminate the balancer as the source of the problem.
If the balancer timing mark is at zero with the piston at tdc.
Then you can move on to the next step.
Let us know what you find and just start with that step and then we can go on
good luck, it will all make sense when you are done

 

[Moparmat2000]

A 94 will show a lean condition on the computer if the fuel pump failed. At least mine did. Check spark too. I might be late to this party.