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2G Need some serious help. Timing belt slipped off?

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
Hello all,

Got a unique issue here that I need advice on. My coworker has a 1997 eclipse turbo. We were in the parking lot at work, looking over the engine and BS'ing as car guys do. We somehow notice the belt on the cam sprockets seemed "not as tight as it should be" and I accidentally pulled it off!

For how easy it seemed to come off, it was a bear to get back on. We were trying everything. We moved with difficulty one of the cam gears (closest to the windshield) A tiny bit in an attempt to get it back on with no luck. Stupid I know.

We finally got it back on. The car doesn't start now. Obviously I suspected the timing was off. I looked up the correct timing for the cam gears. We have both dowel pins in the 12 O'clock position and the timing marks facing each other. The strange part is the mark on the one cam sprocket moves once the belt is put on and the engine turned over (again the cam gear closest to the windshield). I noticed upon taking the belt off again that when lined up, the sprocket in question has a bit of play (2 or 3 teeth worth in a clockwise direction from the 9 o'clock position but not counterclockwise which then causes the mark to be of from the correct 3 and 9 O'clock position which causes the timing marks to not line up again when trying to turn the motor over. Basically the one sprocket goes to the 10 o'clock position. Can we set the sprocket back to say just below the 9 o'clock position so that it "settles" to the correct 9 o'clock position once the belt is back on and the engine turned over?

Am I over thinking this or? I know nothing about these cars which is the problem. I just hope nothing got ruined in the process of being stupid. Thank you for any advice you may have.
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
Sorry to inform you that you will be lucky if you didn't already bend something. Your only course of action now is to remove the covers, find out where the crank is and reset everything. Do not rotate anything at this point. Not until you find out what is what. The fact that it doesn't start now is the worst symptom.
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
Sorry to inform you that you will be lucky if you didn't already bend something. Your only course of action now is to remove the covers, find out where the crank is and reset everything. Do not rotate anything at this point. Not until you find out what is what. The fact that it doesn't start now is the worst symptom.
Thank you. I really appreciate your input. I will do as you said and find out where the crank is timing wise. Could the crank have moved from its original position in regards to timing? If so how? I was under the impression that since only the one cam sprocket was moved that this would be the only adjustment required to get everything back in correct timing sequence. Thank you for taking the time to read and reply. I really want to understand so I can fix my mistake and get my coworkers nice car back on the road.

So the fact it doesn't start is a bad sign?
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
Hello all,

Got a unique issue here that I need advice on. My coworker has a 1997 eclipse turbo. We were in the parking lot at work, looking over the engine and BS'ing as car guys do. We somehow notice the belt on the cam sprockets seemed "not as tight as it should be" and I accidentally pulled it off!
I wanted to elaborate. This immediately tells you the tension isn't correct. You will have to reset at a minimum or possibly replace any defective parts that caused this.
For how easy it seemed to come off, it was a bear to get back on.
when the belt came off the hydraiulic tension will fully extend assuming its working.
We were trying everything. We moved with difficulty one of the cam gears (closest to the windshield) A tiny bit in an attempt to get it back on with no luck. Stupid I know.
Not sure how you knew how to align anything unless you reset everything. If you just put it back on with no regard to anything unfortunately it's unlikely the valves are in time.
We finally got it back on. The car doesn't start now. Obviously I suspected the timing was off. I looked up the correct timing for the cam gears. We have both dowel pins in the 12 O'clock position and the timing marks facing each other.
you must line up the crank also. Cam marks alone are only half the equation.
The strange part is the mark on the one cam sprocket moves once the belt is put on and the engine turned over (again the cam gear closest to the windshield). I noticed upon taking the belt off again that when lined up, the sprocket in question has a bit of play (2 or 3 teeth worth in a clockwise direction from the 9 o'clock position but not counterclockwise which then causes the mark to be of from the correct 3 and 9 O'clock position which causes the timing marks to not line up again when trying to turn the motor over. Basically the one sprocket goes to the 10 o'clock position. Can we set the sprocket back to say just below the 9 o'clock position so that it "settles" to the correct 9 o'clock position once the belt is back on and the engine turned over?

Am I over thinking this or? I know nothing about these cars which is the problem. I just hope nothing got ruined in the process of being stupid. Thank you for any advice you may have.
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
Thank you for elaborating. Basically the car ran great before this. If the only thing timing wise that changed was moving one cam sprocket slightly, why would the crank be off now is my question? Wouldn't the only issue be the one cam sprocket being not lined up correctly?

I understand that everything works together in order to get the correct timing sequence. I'm just puzzled as why the crank would be off timing now in regards to the above scenario.

That isn't to say I won't check it because I will. It's just I can't work on the car until Monday and the fact I caused issue to a car that isn't mine is driving me nuts. Thank you for your patience with all my questions.
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
Thank you for elaborating. Basically the car ran great before this. If the only thing timing wise that changed was moving one cam sprocket slightly, why would the crank be off now is my question? Wouldn't the only issue be the one cam sprocket being not lined up correctly?
You're making a lot of assumptions if you didn't actually look at it.
I understand that everything works together in order to get the correct timing sequence. I'm just puzzled as why the crank would be off timing now in regards to the above scenario.

That isn't to say I won't check it because I will. It's just I can't work on the car until Monday and the fact I caused issue to a car that isn't mine is driving me nuts. Thank you for your patience with all my questions.
Report back what you find.
I'm a little confused. Did you or did you not take the covers off and try to reset everything?
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
You're making a lot of assumptions if you didn't actually look at it.

Report back what you find.
I'm a little confused. Did you or did you not take the covers off and try to reset everything?
According to my coworker his car ran great before.

The only cover that we took off is the cam gear cover showing the belt. The belt was slipped off the top of the cam gear by accident and the belt was reinstalled quickly. This was all done in the parking lot at work. I haven't done anything since.
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
According to my coworker his car ran great before.

The only cover that we took off is the cam gear cover showing the belt. The belt was slipped off the top of the cam gear by accident and the belt was reinstalled quickly. This was all done in the parking lot at work. I haven't done anything since.
You're going to have to start over. My original statement stands. Take it all apart, reset it and go from there. You will be lucky if you didn't bend valves based on what you're saying.
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
Pauley. Is it even possible to slide the belt back onto the cams with the tensioner fully extended?
Probably not but in this case I will take an educated guess and say the tensioner may have failed and that's why it was loose in the first place.

Instead of speculating as it no longer matters OP must take it apart and look and see what is what. There is no choice at this point but to remove covers and look.
OP are you skilled enough to do all this?
 
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waltah

Proven Member
369
153
Mar 2, 2011
fairfield, Virginia
What Paul hasn't said in so many words is these are 'interference;' engines. That is, the pistons and the valves at different times in the rotation enter the same space at the top of the cylinder. This is fine as long as they're not there at the same time -- that is, as long as the timing is correct.

When you have trouble is when one or both sets of valves gets off by a couple teeth or more -- I think one doesn't do it though there will be a power loss. Then the pistons and valves collide: The valves will always be losers -- bent or maybe broken off. There can be other damage depending on the situation.

The bent valves don't close tightly and the engine will not run That is why 'doesn't run now' is a bad sign.

When there is any doubt about the valve timing of one of these engines, the engine must not be turned until you've got it figured out and everything is synched properly again. That must be done with care to avoid bending valves in the process.

Basically you take the belt off and move the pistons out of the way by the shorted route -- so the ones nearest the top move down. Park 'em near halfway. Then move the two camshafts until the dowels are up and the marks point to each other. In this position the valves should all be closed -- take the valve cover off to be sure this is so. (If not, then you likely have a bent valve.) Then turn the crank forward to TDC. Then put the timing belt back on correctly (including on the oil pump sprocket and correct setting of the upper balance shaft) and double check that timing is right for everything when you turn the crank a couple revolutions forward.

The retiming can be done in a parking lot with ordinary tools if you're familiar with routine internal engine work. Otherwise it should go to a shop. After retiming then double check to see that the engine turns freely by hand and if so it's okay to check the compression. But a mechanic who can do the retiming properly likely knows what to do next.

Icky situation ... good luck with it!
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
Probably not but in this case I will take an educated guess and say the tensioner may have failed and that's why it was loose in the first place.

Instead of speculating as it no longer matters OP must take it apart and look and see what is what. There is no choice at this point but to remove covers and look.
OP are you skilled enough to do all this?
Yes. I have no problem working on cars. I've done everything from rebuilding engines to setting ring and pinions in rear end assemblies. I just need the resources for proper procedure and away I go.

What Paul hasn't said in so many words is these are 'interference;' engines. That is, the pistons and the valves at different times in the rotation enter the same space at the top of the cylinder. This is fine as long as they're not there at the same time -- that is, as long as the timing is correct.

When you have trouble is when one or both sets of valves gets off by a couple teeth or more -- I think one doesn't do it though there will be a power loss. Then the pistons and valves collide: The valves will always be losers -- bent or maybe broken off. There can be other damage depending on the situation.

The bent valves don't close tightly and the engine will not run That is why 'doesn't run now' is a bad sign.

When there is any doubt about the valve timing of one of these engines, the engine must not be turned until you've got it figured out and everything is synched properly again. That must be done with care to avoid bending valves in the process.

Basically you take the belt off and move the pistons out of the way by the shorted route -- so the ones nearest the top move down. Park 'em near halfway. Then move the two camshafts until the dowels are up and the marks point to each other. In this position the valves should all be closed -- take the valve cover off to be sure this is so. (If not, then you likely have a bent valve.) Then turn the crank forward to TDC. Then put the timing belt back on correctly (including on the oil pump sprocket and correct setting of the upper balance shaft) and double check that timing is right for everything when you turn the crank a couple revolutions forward.

The retiming can be done in a parking lot with ordinary tools if you're familiar with routine internal engine work. Otherwise it should go to a shop. After retiming then double check to see that the engine turns freely by hand and if so it's okay to check the compression. But a mechanic who can do the retiming properly likely knows what to do next.

Icky situation ... good luck with it!
Thank you very much for the information! This helps me out quite a bit. I'm going to look at it tomorrow and see what I can do. Worse comes to worse, I'll hook up the car trailer and bring her back to my house for the necessary repairs.
 

pauleyman

DSM Wiseman
8,124
2,690
Nov 19, 2011
oklahoma city, Oklahoma
Yes. I have no problem working on cars. I've done everything from rebuilding engines to setting ring and pinions in rear end assemblies. I just need the resources for proper procedure and away I go.


Thank you very much for the information! This helps me out quite a bit. I'm going to look at it tomorrow and see what I can do. Worse comes to worse, I'll hook up the car trailer and bring her back to my house for the necessary repairs.
Good to know. We can help you fill in the gaps where you may be unfamiliar with the platform. Personally I would skip the reset and proceed as follows. You're going to have the belt off anyway.
Get the pistons down the bore some and remove the valve cover. You can likely quickly spot if there are loose rockers possibly indicating a bent vslve. Further still you could remove cams and see how valves sit relative to one another. That's pretty quick and easy. Let us know how you proceed.
 

waltah

Proven Member
369
153
Mar 2, 2011
fairfield, Virginia
Yes. I have no problem working on cars. I've done everything from rebuilding engines to setting ring and pinions in rear end assemblies. I just need the resources for proper procedure and away I go.

Thank you very much for the information! This helps me out quite a bit. I'm going to look at it tomorrow and see what I can do. Worse comes to worse, I'll hook up the car trailer and bring her back to my house for the necessary repairs.
Super. One resource you're going to need is the specific instructions for setting up the timing belt. This is covered as part of replacing the belt in the shop manual. There's a manual that's downloadable somewhere on this site and you need to read the procedure before you start as some parts are not obvious.

Timing belts are one of those 'get it right the first time or at best you have to do it all over again' jobs on these cars. Watch out for correct setting up of the oil pump gear (to get the lower balance shaft in the right place) and the secondary belt for the upper balance shaft.

If the current timing belt is worn this might be a good time to replace it -- maybe adds 50% to the amount of work since you must remove other accessory belts and the driver end engine mount to do it.

You'll definitely need to check out the belt tensioner -- the belt should have been too tight to allow it to just slide off so it at least needs adjustment. It's hydraulic but even without oil pressure it should be too snug for that to happen.
 
Last edited:

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
Good to know. We can help you fill in the gaps where you may be unfamiliar with the platform. Personally I would skip the reset and proceed as follows. You're going to have the belt off anyway.
Get the pistons down the bore some and remove the valve cover. You can likely quickly spot if there are loose rockers possibly indicating a bent vslve. Further still you could remove cams and see how valves sit relative to one another. That's pretty quick and easy. Let us know how you proceed.
Confirmed. The intake valves are bent. Hoping just the head needs replaced along with timing belt and proper timing set.
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
That's a shame. Let us know if you need help. Timing belt on this car is very specific to get right.
Thank you sir. I appreciate you and everyone else's help with this unfortunate situation. Since the car isn't mine, my plan was to R&R the head myself but have a shop do the timing. I'm sure I can do it correctly but since its not my vehicle, I don't like taking chances.
 

1990TSIAWDTALON

Moderator
9,261
5,056
Nov 14, 2013
Independence, Kansas
I will be doing the same thing to a "new to me" 90 TSI. The PO took the intake cam gear off for use on some other car (but WHY, it was a running car?). Mine appears to be "in time" but I am not risking anything. I will tear the front off and reset everything so that this same thing doesn't happen.
You can maybe get by with a set of used valves if you find any in the Classifieds. Have your machinist look at the valve guides as sometimes they will crack when the valve gets bent. I'm sure the head is salvageable or a ready to go head would take a lot of work out of the job.
 

ChristianPastor

Probationary Member
15
7
May 28, 2022
Superior, Wisconsin
That's a shame. Let us know if you need help. Timing belt on this car is very specific to get right.
Ok, a little update. The car is getting towed to my house tomorrow. The initial plan was to get a complete head and just R&R. But I'm having real trouble finding an assembled 7 bolt 4G63t head! I'm guessing I'll have to purchase new guides and valves etc and send the old head off to a shop for a rebuild.

Other than that. I called a local shop and they want over $1400 to just put a timing belt on. It can't be that difficult? Can you point me to the correct sequence to time these engines? My initial assumption was to lock the cam gears "in time", move the crank to the correct timing mark on the block and make sure the 1st piston is down below a bit of TDC. Then I rotate the crank with the timing belt on to make sure everything is good i.e. nothing hits and all the timing marks stay aligned? I do thank you very much for your information. This whole situation just sucks and I have no knowledge of these engines.
 

Dericsh

Supporting Member
1,238
494
Nov 25, 2002
Pearl River, Louisiana
Ok, a little update. The car is getting towed to my house tomorrow. The initial plan was to get a complete head and just R&R. But I'm having real trouble finding an assembled 7 bolt 4G63t head! I'm guessing I'll have to purchase new guides and valves etc and send the old head off to a shop for a rebuild.

Other than that. I called a local shop and they want over $1400 to just put a timing belt on. It can't be that difficult? Can you point me to the correct sequence to time these engines? My initial assumption was to lock the cam gears "in time", move the crank to the correct timing mark on the block and make sure the 1st piston is down below a bit of TDC. Then I rotate the crank with the timing belt on to make sure everything is good i.e. nothing hits and all the timing marks stay aligned? I do thank you very much for your information. This whole situation just sucks and I have no knowledge of these engines.
I think you’ll find this site useful, it’s old but so are these cars.

VFAQ

Edit: have you checked with Rix Racing for a head? They are a supporting vendor here that sells used parts.
 
Last edited:

TK's9d2TSi

Supporting Member
6,423
3,387
Sep 11, 2017
Cincinnati, Ohio
That price must be for r&r the head and put it back together. Setting timing literally takes a few minutes. Setting the correct tension, an few extra minutes. It’s not difficult at all. Lots of videos on yt as well
 

waltah

Proven Member
369
153
Mar 2, 2011
fairfield, Virginia
Other than that. I called a local shop and they want over $1400 to just put a timing belt on. It can't be that difficult? Can you point me to the correct sequence to time these engines?
I don't think that's totally unreasonable. The labor rate might be $100/hr. Here's the process from memory:
1. Remove accessory belts.
2. Raise the left front wheel and take it off.
3. Remove the plastic splash shield.
4. Support the front of the engine and remove the front engine mount. (Timing belt goes around it.) You can skip this step if keeping the old timing belt -- only recommended if brand new.
5. Remove the crank pulley and vibration damper.
6. Remove all three pieces of the timing belt cover.
7. Remove the timing belt.
8. Unless it is new the #2 toothed belt that drives the upper balance shaft should be removed/replaced. If this belt fails it can take out the timing belt ...
9. Check out the timing belt tensioner. Since the timing belt slipped off easily, it is at least suspect. Minimum would be badly out of adjustment. If in doubt replace it, ditto the idler pulley. The tensioner also requires adjustment but I don't remember those steps -- 10 years since I did that job.

Consider also replacing the water pump (not a big job) and the oil pump (bigger job) at this time.

Now you can replace the timing belt itself. This involves correctly positioning the crank sprocket, both camshaft gears, and the oil pump sprocket and you must remove a plug in the block to be sure about the oil pump sprocket -- it drives the lower balance shaft via 2:1 reduction and no outside mark assures correct placement of that shaft.

When you get the belt on and everything's tight turn the engine over a couple times and be sure the marks are still correct as it's easy to make a mistake and be off a tooth due to slack in the belt.

Then reverse all the above. 14 hours for a skilled mechanic? Wouldn't surprise me a bit. Personally I'd set aside a week of part time work and I'd call myself mid-grade skilled.

THE ABOVE IS FROM MEMORY -- Look it up in the book for the real info! The shop manual is online here.

Since reading your story I have tried the experiment on both my 4g63 cars. I cannot slide the timing belt off the pulley on either one, in fact I can't even get it against the timing cover. So I think that tensioner was pretty far off and that your friend's engine was not far from flipping a loop of belt over a tooth on the exhaust cam. That leads to a sudden loss of power and is your last warning that the timing belt area needs attention.
 
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