Acceptable timing chain slack?
11-25-2017, 07:07 PM
#1
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Acceptable timing chain slack? Hello!
I had to pull a switch-a-roo on my lower crank timing gear. The C5R chain now seems a little looser than with the other gear but doesn't seem to be "too" loose.
I would love some feedback!
I had to pull a switch-a-roo on my lower crank timing gear. The C5R chain now seems a little looser than with the other gear but doesn't seem to be "too" loose.
I would love some feedback!
11-25-2017, 08:43 PM
#2
When the rollers get oil on them and the block expands from the thermal expansion the cam moves north and itll be tighter
Aluminum blocks are so different. Main bearing clearances are in the .0013-.0018 range at room temp as the main bearing housings will expand and open those numbers up at operating temps.
Aluminum blocks are so different. Main bearing clearances are in the .0013-.0018 range at room temp as the main bearing housings will expand and open those numbers up at operating temps.
11-29-2017, 02:52 PM
#3
Looks good to me but also hard to tell because your cam is rocking a little letting all the slack go to one side and making the slack seem a bit exaggerated.
If you held the cam centered and checked slack you'd see a very small amount of movement on each side.
I agree with all that ARshale posted too.
However, what gear was there before? Did you change brands? Can you go back to the original brand, or even the original gear?
If you held the cam centered and checked slack you'd see a very small amount of movement on each side.
I agree with all that ARshale posted too.
However, what gear was there before? Did you change brands? Can you go back to the original brand, or even the original gear?
11-29-2017, 03:21 PM
#4
Looks good to me but also hard to tell because your cam is rocking a little letting all the slack go to one side and making the slack seem a bit exaggerated.
If you held the cam centered and checked slack you'd see a very small amount of movement on each side.
I agree with all that ARshale posted too.
However, what gear was there before? Did you change brands? Can you go back to the original brand, or even the original gear?
If you held the cam centered and checked slack you'd see a very small amount of movement on each side.
I agree with all that ARshale posted too.
However, what gear was there before? Did you change brands? Can you go back to the original brand, or even the original gear?
11-29-2017, 03:48 PM
#5
I think the cam only moved once near the end of the video. Your slack looks very much like the slack on the chain in my 6500 mile 6.0 (I just pulled it apart to install a cam). Mine might have had even a little more slack. When the crank is spinning the cam, the drivers side of the chain will be tight!
Edit: Watching carefully it moves each time he goes to the other side and I bet the video started with all slack to the side he's pulling on.
Either way, I say send it.
11-30-2017, 10:37 AM
#9
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Cam Timing + AL Block Growth Hi All, this is "great" tech about timing chain tension AND NO "tech" with reference to the effects of this tension on Cam Timing, no report ?
I have that data.
Lance
I have that data.
Lance
11-30-2017, 11:35 PM
#10
After lashing the valves the cam retarded 1.25 degrees from originally checked
This was with a belt drive however the impact of the stiff *** valve springs made a difference
Basically learned why to use a crank trigger AND belt drive front distributor.
12-01-2017, 10:24 AM
#11
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C-DBug/TW-DBug Hi AR, yes one reason, NOT the important reason.
The GM58x (60-2) TW has much information when decode is correct.
The Crankshaft Acceleration can be recorded.
Examples :
Missfire Detection = OBD-II REQUIREMENT
Individual measurement of EACH cylinder's performance
Timing Chain Stretch when referenced to the CAS
Engine Balance
Knock Detection
THAT accuracy IS .25* at a 2500RPM Acceleration Rate.
Lance
The GM58x (60-2) TW has much information when decode is correct.
The Crankshaft Acceleration can be recorded.
Examples :
Missfire Detection = OBD-II REQUIREMENT
Individual measurement of EACH cylinder's performance
Timing Chain Stretch when referenced to the CAS
Engine Balance
Knock Detection
THAT accuracy IS .25* at a 2500RPM Acceleration Rate.
Lance