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View Full Version : valve lash change,why????


396_WAYS_TO_SPIT
07-16-2005, 07:48 PM
my valve lash went from .024 to .027
what would cause this?
bbc,solid cam
Fiat48
07-16-2005, 07:50 PM
Most likely:
Different engine temperature than when you set the valves before. (Heat)
Adjuster moved.
.003 is no big deal.
For a better valve adjustment:
Adjust the intake valve as the exhaust just opens.
Adjust the exhaust valve as the intake is almost closed.
396_WAYS_TO_SPIT
07-16-2005, 08:50 PM
Most likely:
Different engine temperature than when you set the valves before. (Heat)
Adjuster moved.
.003 is no big deal.
For a better valve adjustment:
Adjust the intake valve as the exhaust just opens.
Adjust the exhaust valve as the intake is almost closed.
ok that sounds good. Should I set them at .023 cold to make up for the heat difference? Just curious.....
396
Squirtin Thunder
07-16-2005, 08:57 PM
Most likely:
Different engine temperature than when you set the valves before. (Heat)
Adjuster moved.
.003 is no big deal.
For a better valve adjustment:
Adjust the intake valve as the exhaust just opens.
Adjust the exhaust valve as the intake is almost closed.
BTW - Michael that is the way you should do all valves including Tyros. Hurry up he needs your help degreeing his cam !!! Stop ****in around !!!
Fiat48
07-16-2005, 10:10 PM
On aluminum heads we see a growth of .004 or more between hot and cold. Not so much on a cast iron head. Just bear in mind to try to keep the engine temp the same when you are comparing valve adjustments.
Squirtin Thunder
07-16-2005, 10:39 PM
On aluminum heads we see a growth of .004 or more between hot and cold. Not so much on a cast iron head. Just bear in mind to try to keep the engine temp the same when you are comparing valve adjustments.
With the temp we have been seeing the blocks are already hot before firing !!!
I was working on an engine today that has not been started in days and I have two burn marks on my arms from the Log exaust manifolds.
Jet City
07-16-2005, 10:47 PM
In my Crane instructions it states to add .002 lash when adjusting an iron head/block engine cold.
Fiat48
07-16-2005, 11:02 PM
That's the not so much. About a couple thousandths.
Blown 472
07-17-2005, 05:19 AM
Keep a close eye on that lash if it keeps opening up then your cam is going flat.
396_WAYS_TO_SPIT
07-17-2005, 01:29 PM
Most likely:
Different engine temperature than when you set the valves before. (Heat)
Adjuster moved.
.003 is no big deal.
For a better valve adjustment:
Adjust the intake valve as the exhaust just opens.
Adjust the exhaust valve as the intake is almost closed.
bob, I am almost ready to fire her up. I double checked every valve just to be sure. Oh and by the way I already had a bottle of gm lube in my pan to start with. i just added another bottle like you said;)
396
GofastRacer
07-17-2005, 08:05 PM
bob, I am almost ready to fire her up. I double checked every valve just to be sure. Oh and by the way I already had a bottle of gm lube in my pan to start with. i just added another bottle like you said;)
396
So you get it all broke in??, how did the filter look???..