Timing Belt Light
09-07-2006, 04:17 PM
#16
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Originally Posted by Andrew Olson
Bill, I disagree with your assessment. The light comes on when the car is started after a long down period (I think sifficiently long that the oil in the tensioner has reverted to ambient temperature).
The light does not come on after a restart in the afternoon. This would indicate (to me) that the block has sufficiently transfered enough heat into the tensioner to increase the tension - thus no light. If the light came on regardless, then I would agree, but this little fact seems to indicate that his tension could be low.
The light does not come on after a restart in the afternoon. This would indicate (to me) that the block has sufficiently transfered enough heat into the tensioner to increase the tension - thus no light. If the light came on regardless, then I would agree, but this little fact seems to indicate that his tension could be low.
I have seen erratic operation of the system that was still the wire having come off the spade and making intermittent contact.
If the tension is running at the high end of the window when cold, then I can't see it being a loose belt. If anything, the Kempf gauge would read low from loss of spring tension over time.
Sorry for missing the piece of info that the warning system only trips when cold.
09-07-2006, 05:13 PM
#17
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The Kempf tool is throwing me a bit. We assume that it either in working spec or low, but the only way to tell for sure would be to test with another tool.
I find that a loose spade to correlate with engine temp pretty hard to believe, but I guess it could happen.
One thing I've noticed on my car is that the oil compartment on the SC tends to stay warm longer that the rest of the engine bits. I'm not a chemist, but it seems to me that oil has pretty good thermal retention tendancies (what I mean is that oil takes a while to warm up and cool down compared to the rest of the car). This would explain why in the morning, the light comes on after 3 min as the oil in the tensioner is still cold and has not transfered its heat to the bi-metal plates. I suspect that if Warren were to turn the car off after say... 10 min, and restart it, the light would not come on.
Warren-
I would suggest you re-check the tension when the engine is BONE COLD! Tension it to the upper end of the window (assuming it's in the middle or lower) and report the results. If you find it's within spec of your tool, I'd see if there is another tool you can borrow in the area to double check.
Ding ding ding... can I ask... where on the belt are you measuring the tension? This might prove valuable. Do you have a picture by chance?
I find that a loose spade to correlate with engine temp pretty hard to believe, but I guess it could happen.
One thing I've noticed on my car is that the oil compartment on the SC tends to stay warm longer that the rest of the engine bits. I'm not a chemist, but it seems to me that oil has pretty good thermal retention tendancies (what I mean is that oil takes a while to warm up and cool down compared to the rest of the car). This would explain why in the morning, the light comes on after 3 min as the oil in the tensioner is still cold and has not transfered its heat to the bi-metal plates. I suspect that if Warren were to turn the car off after say... 10 min, and restart it, the light would not come on.
Warren-
I would suggest you re-check the tension when the engine is BONE COLD! Tension it to the upper end of the window (assuming it's in the middle or lower) and report the results. If you find it's within spec of your tool, I'd see if there is another tool you can borrow in the area to double check.
Ding ding ding... can I ask... where on the belt are you measuring the tension? This might prove valuable. Do you have a picture by chance?
09-07-2006, 05:44 PM
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Sorry - I do not have a picture. The last few checks with the tool were done as close to the engine centre as you can get with the one cover off. The last adjustment I did was in the upper end of the tool range - about 3/4 in the window I would say. Tonight, I will take a look again and will update tomorrow.
Yes, it throws me that it could be tension oil. I understand that when it is warm, it will contract but is it really that much. Of course it is warmer during the day but I can leave it parked for several hours during the day and the light never goes on. It goes on every cold morning only. As a matter of fact, this past weekend I did not drive it until about noon and the light did not come on. This would indicate temp related as opposed to period of time.
Thanks for all the comments - interesting stuff.
Yes, it throws me that it could be tension oil. I understand that when it is warm, it will contract but is it really that much. Of course it is warmer during the day but I can leave it parked for several hours during the day and the light never goes on. It goes on every cold morning only. As a matter of fact, this past weekend I did not drive it until about noon and the light did not come on. This would indicate temp related as opposed to period of time.
Thanks for all the comments - interesting stuff.
09-07-2006, 05:52 PM
#19
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Originally Posted by Andrew Olson
The Kempf tool is throwing me a bit. We assume that it either in working spec or low, but the only way to tell for sure would be to test with another tool.
I find that a loose spade to correlate with engine temp pretty hard to believe, but I guess it could happen.
One thing I've noticed on my car is that the oil compartment on the SC tends to stay warm longer that the rest of the engine bits. I'm not a chemist, but it seems to me that oil has pretty good thermal retention tendancies (what I mean is that oil takes a while to warm up and cool down compared to the rest of the car). This would explain why in the morning, the light comes on after 3 min as the oil in the tensioner is still cold and has not transfered its heat to the bi-metal plates. I suspect that if Warren were to turn the car off after say... 10 min, and restart it, the light would not come on.
Warren-
I would suggest you re-check the tension when the engine is BONE COLD! Tension it to the upper end of the window (assuming it's in the middle or lower) and report the results. If you find it's within spec of your tool, I'd see if there is another tool you can borrow in the area to double check.
Ding ding ding... can I ask... where on the belt are you measuring the tension? This might prove valuable. Do you have a picture by chance?
I find that a loose spade to correlate with engine temp pretty hard to believe, but I guess it could happen.
One thing I've noticed on my car is that the oil compartment on the SC tends to stay warm longer that the rest of the engine bits. I'm not a chemist, but it seems to me that oil has pretty good thermal retention tendancies (what I mean is that oil takes a while to warm up and cool down compared to the rest of the car). This would explain why in the morning, the light comes on after 3 min as the oil in the tensioner is still cold and has not transfered its heat to the bi-metal plates. I suspect that if Warren were to turn the car off after say... 10 min, and restart it, the light would not come on.
Warren-
I would suggest you re-check the tension when the engine is BONE COLD! Tension it to the upper end of the window (assuming it's in the middle or lower) and report the results. If you find it's within spec of your tool, I'd see if there is another tool you can borrow in the area to double check.
Ding ding ding... can I ask... where on the belt are you measuring the tension? This might prove valuable. Do you have a picture by chance?
Yes, I understand you'd expect an electrical break to be constant. I've seen otherwise. Until proven otherwise, if the belt tension is OK and the warning goes off, the problem is an electrical break.
Granted, it's hard to explain why the light only goes off with a cold engine, and low belt tension would be the number one suspicion, so I don't blame anyone for still suspecting improper tension. My other pedantic responses ignored the afternoon situation.
09-07-2006, 06:05 PM
#21
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Originally Posted by Andrew Olson
Hove you thought about making a donation to the shrine? 
09-07-2006, 06:27 PM
#22
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Originally Posted by PorKen
A three minute delay is built into the Central Warning system.
I would like to figure out a way to make it immediate, IE bypass the CWS.
I would like to figure out a way to make it immediate, IE bypass the CWS.
09-07-2006, 06:29 PM
#23
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Originally Posted by Bill Ball
.............Granted, it's hard to explain why the light only goes off with a cold engine, ....
09-07-2006, 07:29 PM
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Originally Posted by heinrich
hop into the pool the next time the light goes off. then look down. cold things shrink. Maybe broken wires too.
I will check everything over tonight.
Maybe it's just that my baby feels she needs some attention. The Z-Car has had the garage and all of the attention for over a month now.
1 hour left of work, then home to check her out. I will first check the tension oil, then the tension, then the wiring.
I will let you know what I find tomorrow.
09-08-2006, 09:12 AM
#27
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Originally Posted by Bill Ball
It is possible that there is a wire break when cold that is not there once it warms up and things expand.
09-08-2006, 12:18 PM
#28
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And the answer is - timing belt tension. Checked tensioner oil - still full, checked wiring - all good, gave it a 3/4 tighten and light does not go on this AM.
Seems odd after I rechecked (Kempf Tool) and retensioned 3 times.
Anyways, all good now - thanks for the advice.
W
Seems odd after I rechecked (Kempf Tool) and retensioned 3 times.
Anyways, all good now - thanks for the advice.
W
09-08-2006, 12:38 PM
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Tell you that in a couple days. I am borrowing a Kempf tool in the next couple of days to do yet another re-check. I wish I would have bought the tool now but I just found another 928 owner here in PG who is going to slide it my way.
W
W