Possible hidden vacuum leak on Z51 after rebuild - where could it be?
09-24-2018, 11:35 AM
#21
09-24-2018, 11:37 AM
#22
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Cylinder head gaskets are one time only and are crushed upon correct torque installation. Got to have new head gaskets.
Elmer
Elmer
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jimxms (09-24-2018)
09-24-2018, 04:28 PM
#27
Safety Car
I think you've got this handled OP just be careful when torquing the heads back down. Make sure the holes are perfectly dry and make sure you follow the torque/angle sequence properly! You mentioned getting ordering a new gasket, but what about the bolts? The factory/stock ones are tty and should only be used once as well. If you have the arp or some other reusable bolts nevermind me
09-24-2018, 04:38 PM
#28
Agreed.
I think you've got this handled OP just be careful when torquing the heads back down. Make sure the holes are perfectly dry and make sure you follow the torque/angle sequence properly! You mentioned getting ordering a new gasket, but what about the bolts? The factory/stock ones are tty and should only be used once as well. If you have the arp or some other reusable bolts nevermind me
I think you've got this handled OP just be careful when torquing the heads back down. Make sure the holes are perfectly dry and make sure you follow the torque/angle sequence properly! You mentioned getting ordering a new gasket, but what about the bolts? The factory/stock ones are tty and should only be used once as well. If you have the arp or some other reusable bolts nevermind me
Sevinn, how would you suggest drying out the holes? Vacuuming them maybe, or trying to wedge a microfiber cloth down into the holes?
My other
09-24-2018, 04:56 PM
#29
Safety Car
Thanks guys. I'm reusing the ARP bolts from my earlier re-build and I've downloaded the ARP instructions for that kit which contains the torquing sequence. I've also got an ACDelco digital torque wrench coming tomorrow, because my 'clicking' torque wrench doesn't always seem to click reliably, and I've purchased a sachet of ARP assembly lube as well. It says to torque the bolts in three equal steps to 115ft-lbs - so I'm assuming finger tight first, then 40ft-lbs, then 80ft-lbs, then 115ft-lbs would be ok?
Sevinn, how would you suggest drying out the holes? Vacuuming them maybe, or trying to wedge a microfiber cloth down into the holes?
My other
Sevinn, how would you suggest drying out the holes? Vacuuming them maybe, or trying to wedge a microfiber cloth down into the holes?
My other
Your torquing process sounds good to me!
Last edited by sevinn; 09-24-2018 at 04:57 PM.
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jimxms (09-24-2018)
09-24-2018, 05:00 PM
#30
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OEM head bolts use degrees as the final TTY adjustment rather than torque. Your torque stages are fine and using the torqueing sequence they show is the same as I see in the book.
Book picture being attached..
Well, the site is being a big suck in allowing me to load a JPG. I thought they had this crap fixed! I'll keep trying to load the left side first. Damn...
Driver Left <-----------
5 inside head------------9-5-1-3-7
5 outside edge of head 10-6-2-4-8
Passenger Right --------------->
5 inside -----------------7-3-1-5-9
5 outside edge of head 8-4-2-6-10
The old fashioned way!
THIS IS FRUSTRATING! I can't attach a JPG! *****!
Book picture being attached..
Well, the site is being a big suck in allowing me to load a JPG. I thought they had this crap fixed! I'll keep trying to load the left side first. Damn...
Driver Left <-----------
5 inside head------------9-5-1-3-7
5 outside edge of head 10-6-2-4-8
Passenger Right --------------->
5 inside -----------------7-3-1-5-9
5 outside edge of head 8-4-2-6-10
The old fashioned way!
THIS IS FRUSTRATING! I can't attach a JPG! *****!
Last edited by eboggs_jkvl; 09-24-2018 at 05:10 PM.
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jimxms (09-24-2018)
09-24-2018, 05:36 PM
#31
My last concern is about the reinstalling of the rockers. I know that they do not need lash setting on them - just bolting down to 22ft-lbs, but fyreant told me that they should only be bolted down when the lifters are not on the cam lobe eccentric.
My plan is to rest all the pushrods in place and then measure how far they protrude from the head. Then crank the engine over with a breaker bar and find out what the lowest position for them is. Then I can start bolting the rockers on to the to the pushrods that I have verified are in their lowest position. Does this sound a reasonable way?
09-24-2018, 06:14 PM
#32
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Thats really handy, thanks man.
My last concern is about the reinstalling of the rockers. I know that they do not need lash setting on them - just bolting down to 22ft-lbs, but fyreant told me that they should only be bolted down when the lifters are not on the cam lobe eccentric.
My plan is to rest all the pushrods in place and then measure how far they protrude from the head. Then crank the engine over with a breaker bar and find out what the lowest position for them is. Then I can start bolting the rockers on to the to the pushrods that I have verified are in their lowest position. Does this sound a reasonable way?
My last concern is about the reinstalling of the rockers. I know that they do not need lash setting on them - just bolting down to 22ft-lbs, but fyreant told me that they should only be bolted down when the lifters are not on the cam lobe eccentric.
My plan is to rest all the pushrods in place and then measure how far they protrude from the head. Then crank the engine over with a breaker bar and find out what the lowest position for them is. Then I can start bolting the rockers on to the to the pushrods that I have verified are in their lowest position. Does this sound a reasonable way?
Honestly, I've just torqued them down to 22 lb ft and they are still going up and down as advertized. If Ant thinks you should do it off lobe, then your method will do it.
Pulling the sparkplugs out will make it easier to turn the crank.
Last edited by eboggs_jkvl; 09-24-2018 at 06:16 PM.
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jimxms (09-25-2018)
09-24-2018, 07:03 PM
#34
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09-24-2018, 07:10 PM
#36
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09-25-2018, 02:32 AM
#38