Timing belt adjustment
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Pro
Joined: Aug 2004
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From: San Jose, CA
Timing belt adjustment
Hi All,
I replaced my timing belt about a year ago and have driven the car about 450 miles since. I have been working on the car a lot in that time so I have not gotten to drive it much...
The car has not hit the reccommended 1500 miles adjustment point but the little light came on while under fairly heavy acceleration...
I Calibrated the Kempf tool against the porsche tool (9201 I think???) and it was fine... so I was going to use it instead of borrowing one. I did this when the center plastic cover was off... when I was reinstalling everything
Right now, I have my passenger side timing belt cover off .. should I take the readling at the point closest to the plastic cover... there is not too much room and the point I can test at does not seem to be at the midpoint between the roller and the cam gear... the picture in the kempf tool instructions showed it being done with the center plasic cover in place.
Anyone have any suggestions... I am going to take a look right now but I am sure you guys all have some opinions/experiences...
Thanks,
LO
I replaced my timing belt about a year ago and have driven the car about 450 miles since. I have been working on the car a lot in that time so I have not gotten to drive it much...
The car has not hit the reccommended 1500 miles adjustment point but the little light came on while under fairly heavy acceleration...
I Calibrated the Kempf tool against the porsche tool (9201 I think???) and it was fine... so I was going to use it instead of borrowing one. I did this when the center plastic cover was off... when I was reinstalling everything
Right now, I have my passenger side timing belt cover off .. should I take the readling at the point closest to the plastic cover... there is not too much room and the point I can test at does not seem to be at the midpoint between the roller and the cam gear... the picture in the kempf tool instructions showed it being done with the center plasic cover in place.
Anyone have any suggestions... I am going to take a look right now but I am sure you guys all have some opinions/experiences...
Thanks,
LO
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From: Bend, Oregon
I do mine per the Kempf instructions, with the center cover still installed. Cold Engine. Tool fits the belt in the first full tooth available with the cover installed. Make sure that you use the tool correctly, keeping it squared to the belt path as you rotate it. It's very consistent if you remember that tip.
Tensioner light under hard accell/higher RPM's is also a sign that you may be low on oil in the tensioner. There's a recent thread on that subject floating around here, maybe a week ago last post to it. Oil dampens the flutter in the belt, especially under higher RPM conditions. Engine builder Marc Thomas (DEVEK) recommends that we use 90W gear oil in the tensioner. It's woth looking/checking to make sure you have oil in there. My last T-belt job was done at the PO's dealer, with no evidence that there was ever any oil in the tensioner at all. Go figure! I had the same light on during a blast between ramps here, and did retension to be sure. Just a little adjustment (one flat on the bolt = 60 degrees rotation) brought the indication back to the middle of the Kempf window and no light. Plus some oil in the tensioner that didn't stay long. Oh well, all new parts now so maybe it will do better.
Tensioner light under hard accell/higher RPM's is also a sign that you may be low on oil in the tensioner. There's a recent thread on that subject floating around here, maybe a week ago last post to it. Oil dampens the flutter in the belt, especially under higher RPM conditions. Engine builder Marc Thomas (DEVEK) recommends that we use 90W gear oil in the tensioner. It's woth looking/checking to make sure you have oil in there. My last T-belt job was done at the PO's dealer, with no evidence that there was ever any oil in the tensioner at all. Go figure! I had the same light on during a blast between ramps here, and did retension to be sure. Just a little adjustment (one flat on the bolt = 60 degrees rotation) brought the indication back to the middle of the Kempf window and no light. Plus some oil in the tensioner that didn't stay long. Oh well, all new parts now so maybe it will do better.
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Joined: Aug 2004
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From: San Jose, CA
Hi fixed I think.
Thanks,
I just finished and took her for a drive...
It was at the lower side of the window... So I retensioned and triple checked and took her out. It did not come on at all... car runs great... so if it does come back on I am going to check the oil... but no signs of leakage etc... it was rebuilt when I did the belt...
belt look healthy... I took my time when doing the job last summer.
LO
I just finished and took her for a drive...
It was at the lower side of the window... So I retensioned and triple checked and took her out. It did not come on at all... car runs great... so if it does come back on I am going to check the oil... but no signs of leakage etc... it was rebuilt when I did the belt...
belt look healthy... I took my time when doing the job last summer.
LO
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From: Nova Scotia
Good results! Did you retension at TDC? I presume that you did, but in playing around, I found that the absolute measure and repeatibility can vary considerably if not performed at TDC.
Adding oil is a 5 min job if you have a piece of tygon tubing to fit on an 'squeeze' type oil can and the bleed screw ( or a syringe as someone else noted).
Adding oil is a 5 min job if you have a piece of tygon tubing to fit on an 'squeeze' type oil can and the bleed screw ( or a syringe as someone else noted).
Thread Starter
Pro
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From: San Jose, CA
Yup TDC
Definitely... and checked it a few times...
I actually had to re-rebuld my tensioner once becuse i squeezed the oil in too hard and it kind of burped out a bit. So I had to get another clamp and re did it... but I just let the oil gravity feed on long enouth with a little pressure and it and eventually all the bubbles stopped...
LO
I actually had to re-rebuld my tensioner once becuse i squeezed the oil in too hard and it kind of burped out a bit. So I had to get another clamp and re did it... but I just let the oil gravity feed on long enouth with a little pressure and it and eventually all the bubbles stopped...
LO
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From: Nova Scotia
Originally Posted by UKKid35
I think the Kempf tool is great but...
If you use the Jageng sound file, you don't have to worry about where to measure, you just pluck the belt.
If you use the Jageng sound file, you don't have to worry about where to measure, you just pluck the belt.
Seriously, listening to PJs sound file on a mickey mouse computer audio speaker does not easily equate to the engine bay music IMHO: Since you have done this, have you done a reference check with the #9021 or #9131 (clone) tool? - and if so, was the correlation exact. Suspecting it was, my compliments - I wouldn't trust my shop worn hearing ...
There is another 'gravity' method published that cantilevers a pexiglass gauge off the tensioned TB: the 'droop' is proportional to the tension applied. Perhaps this is good for those inadequate at 'plucking (up)' the TB, or having a noisy shop.
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From: saratoga, ca
i had the flckering light too, when i put in the new water pump, i pulled out the tensioner plunger, and it was real dirty where it makes contact inside the tensioner. now, its clean and the light is off and not coming back on. tension checked periodically with the "probe" technique. setting with the kempf tool at 3/4 window, calibrated to the porsche tool of 5.0, equals 8mm of movement of the belt. at the full window, 14mm!
MK
MK
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Joined: Nov 2003
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From: London, UK
Originally Posted by Garth S
.. but some of us are tone deaf ..
Seriously, listening to PJs sound file on a mickey mouse computer audio speaker does not easily equate to the engine bay music IMHO: Since you have done this, have you done a reference check with the #9021 or #9131 (clone) tool? - and if so, was the correlation exact. Suspecting it was, my compliments - I wouldn't trust my shop worn hearing ...
There is another 'gravity' method published that cantilevers a pexiglass gauge off the tensioned TB: the 'droop' is proportional to the tension applied. Perhaps this is good for those inadequate at 'plucking (up)' the TB, or having a noisy shop.
Seriously, listening to PJs sound file on a mickey mouse computer audio speaker does not easily equate to the engine bay music IMHO: Since you have done this, have you done a reference check with the #9021 or #9131 (clone) tool? - and if so, was the correlation exact. Suspecting it was, my compliments - I wouldn't trust my shop worn hearing ...
There is another 'gravity' method published that cantilevers a pexiglass gauge off the tensioned TB: the 'droop' is proportional to the tension applied. Perhaps this is good for those inadequate at 'plucking (up)' the TB, or having a noisy shop.
I have also used the plexiglass tool (I was very short of funds at the time and didn't know about the sound file) and it is perfectly adequate. I'm guessing it was developed before the Kempf tool, when the only other option was the hideously expensive Porsche tool. The main problem is that the tip moves through a non vertical arc and it wasn't entirely clear whether to measure the vertical distance or the actual arc.
I've compared both with the Kempf tool (but not the Porsche tool). The sound file is more easily repeatable than the Kempf tool, which is more easily measurable than the plexiglass tool.
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From: Northwest
I have both the Kempf tool and the 9201 gauge...and on my '85 32V I find that I need to tension the belt to the upper part of the Kempf window to get the 5.2 setting. Kempf is sure easy to use but you do have to be careful in how you use it.
Harvey
Harvey
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From: saratoga, ca
"MK" timing belt tension checking tool
cost of an allen wrench or drill bit?
$2.00
not having to remove the timing belt covers to check belt tension periodically?
Priceless
8mm movement seems to be equal to 5.0 on the porsche tool and 3/4 scale of the Kempf tool
Mk
$2.00
not having to remove the timing belt covers to check belt tension periodically?
Priceless
8mm movement seems to be equal to 5.0 on the porsche tool and 3/4 scale of the Kempf tool
Mk
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From: PacNW
Mark - this may be a stoopid question (yes, with two oo's), but doesn't this 8mm depend on just how hard you are pressing? If you knew the belt was tightened per-spec and then measured it, I could see how a person could semi-calibrate their arm, but for the 1st-timer, wouldn't it be difficult to figure out just how hard to press?
Troy
Troy
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From: saratoga, ca
Actually, a good question. However the "probe" technique is for checking the tension. so, if you drilled that hole in the cover, you would then check the tension with the probe. then, 1000miles later, you would check with the probe again and know where you stand. to more specifically answer your question, the tension of the belt goes up exponentially. it may take 10lbs to press the tension with the probe 8mm. then next 1 to 2 millimeters could be 40lbs! basically, its almost like running into a stop. even with the 1-2 mm variance with a strong push vs a weak one, you still are under the 6mm of change when the tension is 4.0 on the porsche tool, or right at the bottom loose mark of the Kempf tool.
Ill tell you , with all of the false alarms , its nice to be able to "probe" the belt and make sure things arent really loose.
after all is said and done, i think the false alarms are due to the dirty push rod contact on the inside the tensioner part of the tensioner plunger before it mates to the part that goest to and mates to the tensioner arm.
However, all someone needs to do, is find a spring that can be calabrated with the probe and use that as a tensioner checker.
an idea for a "Kempf 2" product?
Mk
Ill tell you , with all of the false alarms , its nice to be able to "probe" the belt and make sure things arent really loose.
after all is said and done, i think the false alarms are due to the dirty push rod contact on the inside the tensioner part of the tensioner plunger before it mates to the part that goest to and mates to the tensioner arm.
However, all someone needs to do, is find a spring that can be calabrated with the probe and use that as a tensioner checker.
an idea for a "Kempf 2" product?
Mk
Originally Posted by touque
Mark - this may be a stoopid question (yes, with two oo's), but doesn't this 8mm depend on just how hard you are pressing? If you knew the belt was tightened per-spec and then measured it, I could see how a person could semi-calibrate their arm, but for the 1st-timer, wouldn't it be difficult to figure out just how hard to press?
Troy
Troy
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From: San Jose, CA
tool window - Dynamic range
Hi,
I also found that the high side of the kempf took window calibrates back to the 5.2 reading (for 32 valve cars) . I calibrated to the 9201 tool... maybe the low side mark is for the older cars?
if I remeber the tool's dynamic range is from about 4.5 to 5.2... approx....
LO
I also found that the high side of the kempf took window calibrates back to the 5.2 reading (for 32 valve cars) . I calibrated to the 9201 tool... maybe the low side mark is for the older cars?
if I remeber the tool's dynamic range is from about 4.5 to 5.2... approx....
LO
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From: Y-Bridge City, Zanesville, Ohio
mark kibort Wrote: "However, all someone needs to do, is find a spring that can be calabrated with the probe and use that as a tensioner checker. an idea for a "Kempf 2" product?" Mk
Fisherman's scale?
Fisherman's scale?