I might just cry (belt tensioner warning)
#46
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It is the left side gear (drivers side) where the belt seems to be off track. Your picture shows the belt is running forward of the gear, behind the belt the gear teeth show a lighter spot where the belt was running originally and where it should run.
#47
Rennlist Member
Have you rotated the engine and inspected every tooth on the belt? The bottom pic in your post #39 looks like it shows some belt grunge. If you were off a couple of teeth and then back on, I am thinking you may have missing teeth on the belt.
#48
Three Wheelin'
Thread Starter
I agree some of the belt tooth's does look deteriorated. I have not fully inspected the entire belt.
Question: After checking the TDC or OT , the car cams should be at the notch.
When rotating it to 45 degree's i would assume i would need to rotate to the position close to TDC again. So another full rotation and then stopping at 45 degrees.
My question is regards to Dwayne's instructions.
He displays the cams being at the V notch at 45 degrees. Is this correct? I would assume not, i would guess the cam notch would be about 1.5 iches or so from the V notch.
In regards to the Kempf tool. I was hopeful to see an example on you tube. Well, i could not see any visual showing of it. So i am guessing when the belt bends you should be in the middle mark. If yes, my cars belt is wayyyyyyyyyyyyyyyyyy to loose. I could not get the kempf tool to register in the middle, unless i held the belt by my fingers. Oh my!!
thanks again for all the HELP
Question: After checking the TDC or OT , the car cams should be at the notch.
When rotating it to 45 degree's i would assume i would need to rotate to the position close to TDC again. So another full rotation and then stopping at 45 degrees.
My question is regards to Dwayne's instructions.
He displays the cams being at the V notch at 45 degrees. Is this correct? I would assume not, i would guess the cam notch would be about 1.5 iches or so from the V notch.
In regards to the Kempf tool. I was hopeful to see an example on you tube. Well, i could not see any visual showing of it. So i am guessing when the belt bends you should be in the middle mark. If yes, my cars belt is wayyyyyyyyyyyyyyyyyy to loose. I could not get the kempf tool to register in the middle, unless i held the belt by my fingers. Oh my!!
thanks again for all the HELP
#50
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The crank turns twice for every one turn of the cam. So 45 degrees BTDC on the crank equals the V on the gear at 22.5 degrees from the V on the back plate.
Kempf tool should be positioned on the edge of the center cover. The tool should be between the middle and upper part of the window, approximately at 80 or 90% (although there is discussion on that).
Anyway, since the belt is loose and running forward on the left gear, it is time to take the belt off and see what is broken. Put the crank at 45 DTBD, install the flywheel lock and find out what went wrong.
Kempf tool should be positioned on the edge of the center cover. The tool should be between the middle and upper part of the window, approximately at 80 or 90% (although there is discussion on that).
Anyway, since the belt is loose and running forward on the left gear, it is time to take the belt off and see what is broken. Put the crank at 45 DTBD, install the flywheel lock and find out what went wrong.
#51
Nordschleife Master
Your belt is mis tracking on the drivers side.
What direction did you rotate the engine?
If clockwise, inspect oil pump and 5-8 cam/Y for wear/cracks/damage!
If CCW then you have a failing WP
What direction did you rotate the engine?
If clockwise, inspect oil pump and 5-8 cam/Y for wear/cracks/damage!
If CCW then you have a failing WP
#52
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I agree some of the belt tooth's does look deteriorated. I have not fully inspected the entire belt.
Question: After checking the TDC or OT , the car cams should be at the notch.
When rotating it to 45 degree's i would assume i would need to rotate to the position close to TDC again. So another full rotation and then stopping at 45 degrees.
My question is regards to Dwayne's instructions.
He displays the cams being at the V notch at 45 degrees. Is this correct? I would assume not, i would guess the cam notch would be about 1.5 iches or so from the V notch.
In regards to the Kempf tool. I was hopeful to see an example on you tube. Well, i could not see any visual showing of it. So i am guessing when the belt bends you should be in the middle mark. If yes, my cars belt is wayyyyyyyyyyyyyyyyyy to loose. I could not get the kempf tool to register in the middle, unless i held the belt by my fingers. Oh my!!
thanks again for all the HELP
Question: After checking the TDC or OT , the car cams should be at the notch.
When rotating it to 45 degree's i would assume i would need to rotate to the position close to TDC again. So another full rotation and then stopping at 45 degrees.
My question is regards to Dwayne's instructions.
He displays the cams being at the V notch at 45 degrees. Is this correct? I would assume not, i would guess the cam notch would be about 1.5 iches or so from the V notch.
In regards to the Kempf tool. I was hopeful to see an example on you tube. Well, i could not see any visual showing of it. So i am guessing when the belt bends you should be in the middle mark. If yes, my cars belt is wayyyyyyyyyyyyyyyyyy to loose. I could not get the kempf tool to register in the middle, unless i held the belt by my fingers. Oh my!!
thanks again for all the HELP
Set the crank back on O|T (TDC), and use the Kempf tool to adjust the tension of the belt with the 17mm nut on the tensioner shaft. Do this now, so you avoid a belt tooth skip! Set the tension so the slide on the Kempf tool is in the detent range on the tool. If you search for Kempf tool in the 928 sub forum you will find instructions on how to use it.
Once you have the belt at the correct tension, proceed to inspect the inside of the belt for missing or damaged teeth. Also inspect the belt path to see if you can find why it is not tracking in the center of the gears. If it looks ok, the car can then go back on the road until you replace the timing components.
Since you don't know the condition of anything in there, I would recommend replacement of everything in the belt path, including a new Porkensioner. I know it's a lot of money, but the avoid costs are 10X higher than doing the timing components right.
A) Use Kempf tool and set tension to middle of notched window.
B) Inspect belt carefully with hi intensity light.
C) Inspect belt path gears, WP, and tensioner for problems.
D) Order TB/WP/gears and prepare to replace at soonest oppty.
#53
Nordschleife Master
Forget setting the tension.
You have a problem in there.
Replace the belt, WP, worn gears,
Inspect the oil pump gear make sure it tracks true and isn't loose. Also inspect Y piece behind can gears for cracks.
Rebuild factory tensioner and replace all rollers/idlers or concert to porkensioner. Choice is yours.
You have a problem in there.
Replace the belt, WP, worn gears,
Inspect the oil pump gear make sure it tracks true and isn't loose. Also inspect Y piece behind can gears for cracks.
Rebuild factory tensioner and replace all rollers/idlers or concert to porkensioner. Choice is yours.
#54
Three Wheelin'
Thread Starter
Regards the belt, i just want to replace it. At this point i want to remove the belt, inspect it and other parts of concern.
I re-read the instructions about the Cam gears position at 45 degress. I understand it now. My Apologizes.
thanks again eveyrone!
I re-read the instructions about the Cam gears position at 45 degress. I understand it now. My Apologizes.
thanks again eveyrone!
#55
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Good choice. Call Roger, 817-430-2688. He'll have your 'bits' out to you right away.
If you are going to DIY, just leave the crank at O|T (TDC) for belt replacement. If you replace your cam gears you will likely need the VR32 cam timing tool. When you take the belt off at TDC, one cam will spring one way, and the other cam will spring the other way. When threading the new belt, just have two people there and line the new belt up with the gears by rotating the cam gear from the bolt on the front. You will need to hold the cams in place with the wrench until it is threaded around the tensioner.
If you are going to DIY, just leave the crank at O|T (TDC) for belt replacement. If you replace your cam gears you will likely need the VR32 cam timing tool. When you take the belt off at TDC, one cam will spring one way, and the other cam will spring the other way. When threading the new belt, just have two people there and line the new belt up with the gears by rotating the cam gear from the bolt on the front. You will need to hold the cams in place with the wrench until it is threaded around the tensioner.
#56
Three Wheelin'
Thread Starter
Dwayne's instruction mentions to set up the timing at the 45 degree mark with the fly wheel stop installed.
I was going to use his directions to complete the job.
I guessing you don't follow the same procedure? I would assume there is more than one way to do a job.
Regards the VR32 cam timing tool, is this tool also used to support performance changes. I was thinking a local 928 friend has this tool, but i might be confusing it with another tool
I was going to use his directions to complete the job.
I guessing you don't follow the same procedure? I would assume there is more than one way to do a job.
Regards the VR32 cam timing tool, is this tool also used to support performance changes. I was thinking a local 928 friend has this tool, but i might be confusing it with another tool
#57
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There are more ways than one. If you put the crank at 45 BTDC the valves will never hit the pistons if you turn the crank. They might if you keep the crank at 0|T but doc is worried about the belt skipping or teeth shearing if you turn the crank. The flywheel lock needs to be in place regardless of crank position to take the belt off.
#58
Shameful Thread Killer
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Dwayne's instruction mentions to set up the timing at the 45 degree mark with the fly wheel stop installed.
I was going to use his directions to complete the job.
I guessing you don't follow the same procedure? I would assume there is more than one way to do a job.
Regards the VR32 cam timing tool, is this tool also used to support performance changes. I was thinking a local 928 friend has this tool, but i might be confusing it with another tool
I was going to use his directions to complete the job.
I guessing you don't follow the same procedure? I would assume there is more than one way to do a job.
Regards the VR32 cam timing tool, is this tool also used to support performance changes. I was thinking a local 928 friend has this tool, but i might be confusing it with another tool
If you use the VR32 tool, you can adjust your cam timing for anything you want. If you have access to it, use it to set your cam timing correctly, and get the car running right, then you can go back and move cams around later.
If you think you are going to be moving the cams a lot, then use the 45deg mark on the crank and have at it. Once you are done moving **** around, how are you going to time the cams without putting them back at O|T? It's easier and faster just to leave it at O|T. YMMV
#59
Three Wheelin'
Thread Starter
I had a few minutes to remove the final pulley and harmonic balancer.
I see a lot of beach sand around the engine bay. Interesting
The roller for the tensioner was not against the belt. Free rolling.
Need to read Dwayne 's instruction to see how to remove the belt. I thought the tensioner would release it
I see a lot of beach sand around the engine bay. Interesting
The roller for the tensioner was not against the belt. Free rolling.
Need to read Dwayne 's instruction to see how to remove the belt. I thought the tensioner would release it
#60
Rennlist Member
That roller does freewheel, with little contact, when engine isn't running.
Are you going to replace everything in belt path including water pump?
That is what I would do, unless I could verify the exact version of pump and date it was installed.
Belt doesnt seem traumatized. When was it last done? Looks clean, somebody has been in there. Maybe its a stretchy conti belt. Who knows.
You have to decide whether to invest in the Porkensioner or rebuild the existing stock tensioner, either way will work. Now is the time to do it all, piece by piece, and get it perfect for the next 50K mi.
Dwayne's write up has one issue, IIRC, he omits reference to the spacer washer in the warning light triggering mechanism.
So post up details, part by part, if you have any questions at all, so there is no guesswork.
Are you going to replace everything in belt path including water pump?
That is what I would do, unless I could verify the exact version of pump and date it was installed.
Belt doesnt seem traumatized. When was it last done? Looks clean, somebody has been in there. Maybe its a stretchy conti belt. Who knows.
You have to decide whether to invest in the Porkensioner or rebuild the existing stock tensioner, either way will work. Now is the time to do it all, piece by piece, and get it perfect for the next 50K mi.
Dwayne's write up has one issue, IIRC, he omits reference to the spacer washer in the warning light triggering mechanism.
So post up details, part by part, if you have any questions at all, so there is no guesswork.