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Camshaft and crank alignment


zendriver
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My 97 May have had the timing belt slipped when the distributor froze.

 

No matter how I set tdc or position the distributor I cannot get it to fire properly barely at all.

 

I'd like to loosen the belt and realign The camshaft and crankshaft manually , to insure that is all aligned.

 

Can anyone outline the alignment steps as if the belt had broken?

 

 

 

 

Sent from my iPhone using Tapatalk

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Did you already install the new distributor? With the engine at TDC make sure the rotor is pointing at spark plug wire terminal #1. Make sure you are looking at the correct mark for TDC on the crank.

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I have had the distriubter at cylinder one, even moving it a geartooth each with no better results.

 

"Make sure you are looking at the correct mark for TDC on the crank".

 

 

This is my problem, I think the belt has slipped..

 

I even had the timing belt covers off.

 

Everything I have seen in books and videos states that if at TDC, the left-most crankshaft pully mark, should align at the timing point and at the same time, both cam gear marks should align with their alignemnt marks.

 

I cannot get this to happen.

 

Assuming I am not at TDC, if I rotate the crank 360 degrees, all threee points still do not align up.

 

What I am looking for is the procedure to - without having the belt on, to set the crankshaft and each cam, so that the engins is at TDC, then reinstall the belt.

 

The youtube videos either assume that you are replacing a belt on a already aligned engine, or they skip the procedure, of setting TDC and the cams prior to installing a new belt, if the old one broke.

 

 

 

 

 

 

 

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The crank line and cam dimples only line up simultaneously when first installed. If the engine turns afterwards they won't line up again although your timing, if done properly will still be correct.

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So, How can I tell if the timing belt has slipped?

 

When the distro froze, it actually busted the mount off, so the engine took a pretty hard shot, so it seem possible it could have slipped, at least to me.

 

just loosen and align the 3 points?

Edited by zendriver
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yeah if I were you I would get it all the way down to the cam sprockets, making sure you have the crank at tdc. Loosen and take the belt off, check to make sure the two dimples on the cam sprockets line up with their respective dimples, and check on the crank dimple just the same.

 

Once those are dialed in, put your timing belt back on following the white lines on the belt. For extra measure there's even a tooth count you can do to ensure you don't have it a tooth off. I think between cam dimples you should count 40 teeth, and from the right cam dimple to the crank dimple should be 43.

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Before any of that make sure that the driver's side cam didn't snap. If it broke in the middle the dist rotor will still spin but if it broke close to the cam gear the dist won't turn therefore not fire correctly.

Does the rotor turn as you turn the engine manually with a socket on the main pulley bolt?

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Before any of that make sure that the driver's side cam didn't snap. If it broke in the middle the dist rotor will still spin but if it broke close to the cam gear the dist won't turn therefore not fire correctly.

Does the rotor turn as you turn the engine manually with a socket on the main pulley bolt?

 

Yes the rotor seems to turn normally.

 

 

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When the cams are lined up with the dimples on the rear timing belt cover, does the crank pulley line up with the zero mark? If it doesn't then something is screwed up.

Best bet is do take the timing belt off and redo it with all of the timing marks lined up.

If the belt did slip I would get a new one. Also do a compression test if possible to rule out a snapped cam. If it broke in the middle the dist will still turn but the rear cylinder and maybe center cylinder (4 and 6) might have the corresponding valves not opening and closing. It would show up in the compression test.

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I got it running rough (no ratiator reinstalled yet) etc, but someone needs to please explain this and TDC.

 

 

 

I pull the timing belt covers.all three notches aligned. OK. The distro points to cyl 1.

 

The engine should be at TDC right.?

 

However.

 

The when i put the harmonic balancer back on, the TDC mark is almost 40 degrees past the pointer, sitting at about 9 oclock.

 

If i put a straw in the cylinder 1 moving the harmonic balancer either direction moves the straw (piston) down.

 

Why does the manual state that TDC is set by finding the compression stroke then turning it ti the TDC mark.

 

physically, it It does not work this way.

 

 

 

 

 

 

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Make sure the crank is at zero. The marks on the cam gears don't line up exactly. Looking at the engine,the right cam mark should be a little past the mark on the rear timing belt cover and the left cam dot a little before the mark on the timing cover mark. Also there should be 40 belt teeth between the cam gear dots and 43 between the driver's side cam gear dot and the dot on the crank timing sprocket.

Then the dist rotor should point to the dist cap #1 terminal.

 

Does it look like this?

Edited by rick88ss
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Make sure the crank is at zero. The marks on the cam gears don't line up exactly. Looking at the engine,the right cam mark should be a little past the mark on the rear timing belt cover and the left cam dot a little before the mark on the timing cover mark. Also there should be 40 belt teeth between the cam gear dots and 43 between the driver's side cam gear dot and the dot on the crank timing sprocket.

Then the dist rotor should point to the dist cap #1 terminal.

 

Does it look like this?

yes it did look like that. The tooth count was that also

 

 

 

Sent from my iPhone using Tapatalk

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Then make sure the distributor rotor is pointing to the #1 terminal in the cap. Look at the inside of the dist cap. The terminals on the inside don't match the spark plug wire terminals on top of the cap.

I think there's a pic in the service manual that shows where the rotor should be pointing.

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  • 2 weeks later...
  • 2 weeks later...

Yes, nothing much better, and it only get more wierd.

 

I did do the timeing belt marks that all lined up, put the distro to cyl one.

 

Soemtimes it starts right up, but idles rough. other it wont start at all. It idles ever rough and although i did get it to roughly accerlate some. it wont do it at all now. it starts right up, or not at all. I do have regular spark and im testing fuel pressure, but spraying strting fluid in the TB has never made any difference.

 

the really wierd thing was when it was running even roughly, when it put the timing light on cly 1, the timing marks are at about 10:00, way far away from the timing pointer, telling me maybe the distro is still off?

 

not sure what to look at next

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It's sometimes a little tricky to line up the distributor just right. Line up the crank pulley to TDC with the arrow pointing to zero degrees TDC. Remove the dist hold down bolt and make a note of where it's pointing. Carefully pull out the dist and reinstall it 1 tooth over clockwise and test again with the timing light. Get back

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I did advance the distro one tooth CW and it would not fire at all, so it took it back 2 teeth ccw (1 ccw what it originally was). It started right up (Yay) but ran somewhat rough and the timing mark is about 11:00 which is much better. the timing adjustment is all the way back (retarded?) and when I tried to adjust it, it just ran worse.. the vehice drives ok (did nlot want to drive it too far)

 

I'm going to try to advance it one more tooth this week and see what that does. Getting closer. :)

 

The engine has 300K miles so it may be a little rough anyway but the body is in shape shape and we want to use it as a winter snow,driver only

 

thanks

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I went one more tooth and it made it worse, so that must be the spot.

 

looked at live data from my odbii reader and it showed 7 degrees or so at at idle, even though the timing light showed it way off. Just galt to have it running, so after a fix to the rear exhaust, it need to go out of the garage, so other vehciles can be repaired.

 

Ill fiddle with it a little later.

 

thanks for everyones help.

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Looks like I have the same problem. Just tried to time the ignition after doing valve cover gaskets and the marks are all counter clokwise to the pointer. TDC mark is about 9:00. Mine starts and runs just fine with the exception of high idle. I can't adjust the dist enough by rotating without killing the motor.

 

I guess I musta re installed something off when I did the timing belt a few years ago, lol

 

I'm debating whether to leave it or try to fix.

 

Did you ever figure it out?

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I was looking through one of the older posts on timing belt change and from what I can see, it does look like the crank pulley can be mounted 90 off. I think that may be what you and I have going on here.

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