Too much timing belt travel...

[SVXMAN2001]

Keith, wow you must have had an easy life! just kidding

No need to beg. You've posted multiple times as have others that a possible cause could be the sprockets. Each time someone's posted this I've rechecked the sprockets to try and see if I missed something. Trust me the frustration is on both our ends.

[kwren]

Originally Posted by SVXMAN2001

Keith, wow you must have had an easy life! just kidding

No need to beg. You've posted multiple times as have others that a possible cause could be the sprockets. Each time someone's posted this I've rechecked the sprockets to try and see if I missed something. Trust me the frustration is on both our ends.

If you have actually removed each of them and carefully determined that there is nothing wrong with either the sprocket, the end of the cam shaft that the sprocket goes on and the key and slot that it slides on, you did good! If a visual second take is it, that is another story. Sometimes the sprockets can be a little hard to slip back on and the key does not seat properly. Bolting it on if it didn't seat properly will result in a sprocket that will never line the belt up properly as it turns, but wobble a bit... That could cause the problem of sprocket scraping on the plastic cover, front or back cover.

Keith

[cthommes]

It appears you have unfortunately spent time and money on the red herring of a tensioner pulley...

I've just finished a timing belt / seals replacement last night and can confirm that my tensioner pully (both the one I pulled out and the one I put in) have a small amount of axial play when properly installed. I believe the one I pulled out was factory original, but I can't definitively confirm as I just bought the car a month ago.

Think about it's function (which it seems you already have at this point, so perhaps I'm just practicing typing skills at this point), it pivots about that flared tube on a bushing, and the mount bolt bears on the tube, not on the pulley hub face itself. By its design, there MUST be axial play here in some amount, as the hub slides freely on the tube, until it comes into contact with the bolt face. In other words, the bolt head doesn't bear on the pulley hub, but provides an outer limit retainer of sorts to ensure the hub can not slide forward more than the tiny axial play you have observed.

I've watched the belt travel video, based on that and my own observations during my replacement, it would seem to me that you simply have to have a defective belt. Since the belt movement is clearly ocurring at the exact same point on the belt based on belt markings, it doesn't appear to be a fault of one of the rotational components (pulleys or gears). My speculation of this is due to the fact that the belt will not be in the same linear location from one revolution to the next-- this is obvious by the normal and expected shifting in belt timing marks with respect to the cam/crank gear timing marks with each revolution. So if it was a rotational component runout issue or installation error, I would expect to see belt movement at a different linear point on the belt, coinciding with each revolution of the faulty component.

My opinion is that you have a belt that is untrue. in other words, the belt itself has "runout" if you will (i.e. the edge of the belt is not in a straight line).

I don't know how it would be possible to effectively measure this to confirm, other than to simply try a different belt to see if the problem is eliminated.

Understanding I'm not the voice of experience on this forum as I'm new to the SVX, but I have been turning wrenches for many years and thought I'd throw in my 2 cents.

[cthommes]

Also I will add, my hydraulic tensioner piston moved a very small amount when the pin was pulled, just as you had observed. As I rotated the assembly, the piston did move more as belt slack was taken up during the rotation, but it's final resting spot was nowhere near where it was when I disassembled with the old belt.

I believe others have indicated this as the old belt will be stretched and require more tensioner piston travel to properly tension. Just wanted to confirm with what I saw myself yesterday.

[kwren]

Originally Posted by cthommes

I believe others have indicated this as the old belt will be stretched and require more tensioner piston travel to properly tension. Just wanted to confirm with what I saw myself yesterday.

I realize that reading all 6 pages, God only knows going on how many more there will be, before this ends to properly get the sprockets on You have a lot of catching up to do on your reading, but... the belt is new.

To Superguy:
I am having a lot of trouble just shutting up and allow you fail. I would consider that a personal defeat for myself, with all my dedication to help you succeed. This is no longer "just about you"

Keith

[cthommes]

Originally Posted by kwren

I realize that reading all 6 pages, God only knows going on how many more there will be, before this ends to properly get the sprockets on You have a lot of catching up to do on your reading, but... the belt is new.

Oh believe me, I read them all as I was just about to embark on my own TB replacement that is now nearly finished. I may just go read them all again out of boredom though.

I wasn't clear with the comment you quoted, I meant the old (now removed) belt would obviously have required more tensioner piston travel to accommodate it's stretch, and the newly-installed belt will require much less tensioner piston travel. Just was trying to add some positive affirmation to his observation that the tensioner piston extended much less with the new belt than when it was removed with the old belt still in place.

[cthommes]

Originally Posted by SVXMAN2001

The belt doesn't look defective in any way. WHen I lay it down it does seem to loosly mimic what it looked like when installed on all pulleys and yes it lays flat. Maybe worth mentioning that the T-Belt sat in the box for close to 2 years before install. Could being bunched up in the box have warped it in some way?

I think this is possibly the clue to explore. Bunched up how? Was it twisted or otherwise bent abnormally (obviously it was coiled up somehow, hopefully with bends only in the direction it's supposed to bend around pulleys and whatnot)? Anything of any substantial weight resting on it or the box?

[oab_au]

Originally Posted by cthommes

I think this is possibly the clue to explore. Bunched up how? Was it twisted or otherwise bent abnormally (obviously it was coiled up somehow, hopefully with bends only in the direction it's supposed to bend around pulleys and whatnot)? Anything of any substantial weight resting on it or the box?

I guess the belt could get squashed, but they are quite resilient, and once the engine ran, it would be pulled straight.
If it was distorted, he would have had problems fitting it on to all the pullies at once.

The sound you could hear, was fixed by bending the back cover away from the RHS cam pulley. Now this sound was not constant, it was repetitive. I don't think the cover was moving back and forwards, to hit the pulley. I would think it was the pulley moving, hitting the cover, taking the belt with it.

The way this pulley fits to the cam shaft is quite unusual, even strange. It uses a round peg, in a square keyway. It gets cut by the shoulders of the keyway to distort the 'key', even to shear it off.
When you pull the pulley, and fit it back, it can shave metal off the peg, that ends up between the pulley’s face and the camshaft face, to make the pulley run out.

I think this is what is happening. What do you think?

Harvey.

[kwren]

Originally Posted by oab_au

The way this pulley fits to the cam shaft is quite unusual, even strange. It uses a round peg, in a square keyway. It gets cut by the shoulders of the keyway to distort the 'key', even to shear it off.
When you pull the pulley, and fit it back, it can shave metal off the peg, that ends up between the pulley’s face and the camshaft face, to make the pulley run out.

I think this is what is happening. What do you think?

Harvey.

Well said Harvey...

I have been trying to tell him that for 7 pages...

Keith

[kwren]

Sorry, 6 pages...

Keith

[Conn SVX]

So to solve the problem you need what? New pulleys ? New keys? Sounds like that is what happened, a slight misfit. Would not take a lot at that point to make it wobble .

[cthommes]

Originally Posted by oab_au

I think this is what is happening. What do you think?

Harvey.

I think it's quite possible, and a great thing to check, and the OP says he has rechecked cam pulleys repeatedly. But I'm not him, so I'm not sure. I'm here to throw out other suggestions, assuming that he has checked the cam pulleys repeatedly.

Although, if there was enough runout to cause the pulley to hit the timing cover, I would think it would be visually apparent when watching the videos (just as the timing belt movement was easy to see).

Not being that intimate with the timing case (despite having just finished a timing belt / seals R&R this week), would it be possible for the belt itself to contact a timing cover and cause the cyclical noise? That belt was obviously moving around quite a bit.

And what about my thought that a running out pulley would not cause the timing belt movement at the exact same point on the belt as seen in his first video. Wouldn't the movement be seen at different linear points on the belt, just as the belt timing mark will not line up with the pulley timing mark after each revoloution?

Something else I observed last night on my car. I bought two new accessory belts from O'Reilly to finish up my car. Unfortunately they didn't have a Gates brand for the alt/PS belt, so I bought the cheapo MasterPro instead. Interesting to note that when installed, the Gates belt for the AC was smooth and true while running. The MasterPro alt/PS belt had some back and forth "travel" similar to the OP's timing belt video. Obvisously being a v-grooved belt it would not travel at all, so I'm assuming I was simply seeing belt edges that are not straight...

[kwren]

Originally Posted by cthommes

I think it's quite possible, and a great thing to check, and the OP says he has rechecked cam pulleys repeatedly. But I'm not him, so I'm not sure. I'm here to throw out other suggestions, assuming that he has checked the cam pulleys repeatedly.

Yes... That is what he said. Checking them repeatedly. There are two ways to check them repeatedly... Just take a look at the sprockets hanging on the cam shafts to make sure someone hasn't stolen them, or... take them both off and carefully trying to see what was done wrong.

Logic says that removing each of them "repeatedly" - "many times" and actually trying to see what was done wrong, didn't happen.

Conn SVX replied.
Re: Too much timing belt travel...
So to solve the problem you need what? New pulleys ? New keys? Sounds like that is what happened, a slight misfit. Would not take a lot at that point to make it wobble .

You need to remove them and see what is damaged, then replace that. As of yet, there may not even be major damage, if the cam shaft end is damaged, it will probably have to be replaced as well as the sprocket.

Keith

[icingdeath88]

Originally Posted by kwren

Yes... That is what he said. Checking them repeatedly. There are two ways to check them repeatedly... Just take a look at the sprockets hanging on the cam shafts to make sure someone hasn't stolen them, or... take them both off and carefully trying to see what was done wrong.

Lol. I can see it now...

"check the sprockets..." *looks at sprockets* "yup, they're still there. Must be a problem with something else."

[cthommes]

Originally Posted by icingdeath88

Lol. I can see it now...

"check the sprockets..." *looks at sprockets* "yup, they're still there. Must be a problem with something else."

Perhaps. This thread seems to now only be populated by those attempting to assist with a problem that may not actually even exist at this point.

If it's any consolation, my cam sprockets were removed and replaced without issue, and the car runs great with no strange noises and no longer leaks oil. So someone here has been successful at least!