*resolved* cometic leaking, *i've searched*

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prokronic36
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Posts: 4
Joined: Tue Sep 23, 2008 1:30 pm

*resolved* cometic leaking, *i've searched*

Post by prokronic36 » Thu Jun 27, 2013 12:17 pm

Hi guys....
been trolling here for a long time, search button works wonders so i haven't had to post much. stupid @ss cometic is leaking between cylinder 1 and the front timing cover on both sides of the head like jnt82 did. hoping that he's still on here to lmk if tightening the nuts on the headstuds was a long term fix, or if he had to go back in and redo the headgasket later. everyone else can chime in as well.

i kno the cometic is pos, should have just got the felpro. yes i did get the block/head/upper timing cover/lower timing cover machined. they weren't at the same place, block and lower at the block shot, upper and head at the head shop. who knows what finish they did, but it was done. trying not to pull the head again, but rather do it right than not, but tightening nuts sounds way better than pulling the head off.

stuff on the car
s14 ka24de
arias pistons 20 over
those light ass china rods
clevite bearings
arp mains
arp headstuds (stock diameter) torqed to 60ft-lbs following fsm sequence
brand new oil pump
timing chain kit
91 cams
bc springs/retainers
light port and polish
700cc greddy injectors
greddy fuel rail
jwt tuned ecu
z32 mafs
jgs manifold/dp
gt32 turbo
etc.

any help is appreciated!
much mahalos!
Last edited by prokronic36 on Mon Jul 15, 2013 2:31 pm, edited 1 time in total.

arob987
Knows Some Stuff About 240's!
Posts: 320
Joined: Mon Feb 16, 2009 5:48 pm
Location: memphis,tn

Post by arob987 » Thu Jun 27, 2013 2:47 pm

IMO pull the head and do it right it sounds like you already know you should.and over tightening head studs is just asking to stretch them.just use a felpro if you not going for over 450-500ish.

cosmetics surface requirements are high surface smoothness of 50ra or better.I wouldn't blame the gasket as much as people like to,its more the machinist/customer problem.either not specifying the smoothness needed cause a standard resurfacing is nowhere near 50ra,you have to tell your machinist what you need and why you need those specs.even if you just say 50ra and don't tell him why exactly you may get a thatle do job cause no factory type gasket need a 50ra and the average person can't tell the difference.then some places that do heads all day aren't able to get them that smooth.my machinist had to let a friend of his at another shop that he trusted to do mine cause his machine simply wouldn't do it.I have a good relationship with my machinist he is honest and always fair on pricing.I use to go to different shops cause they were supposedly the best from others and ect but I found it better to find one person you can build a relationship with and they will do you right for years to come.
New turbo setup build in progress-11mm headstuds/cometic head gasket/jwt cam gears added,prec. 6266,gato mani,prec.46mm wg,bigger fmic,mspnp2,z32 trans,spec twin,q45 rear,full energy bushings. Still need injectors,and a few other small things

Old setup-ka24de-wiseco 9:1 pistons,eagle rods,arp studs,jwt s1 cams,brian crower springs and retainers,jgs log mani,t3 57trim .63 a/r,tomei 740cc,38mm turbonetics evolution wastegate,synapse bov,ebay fmic,nistune,j30 lsd.5 speed swap,z32 brakes F&R.

El_Cangri
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Location: Puerto Rico

Post by El_Cangri » Sat Jun 29, 2013 8:09 pm

As with any full metal gasket both surfaces have to be smooth and completely leveled if not you will leak. Happens all the time and people just blame the gasket...

drunknmunky
Knows Some Stuff About 240's!
Posts: 448
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Re: cometic leaking, *i've searched*

Post by drunknmunky » Thu Jul 04, 2013 4:33 pm

My machine shop recommended that I 0-ring my block w/ the cometic. I looked up headgaskets on many forums and that is a good alternative to make sure you have an effective seal.

arob987
Knows Some Stuff About 240's!
Posts: 320
Joined: Mon Feb 16, 2009 5:48 pm
Location: memphis,tn

Re: cometic leaking, *i've searched*

Post by arob987 » Fri Jul 05, 2013 9:01 am

drunknmunky wrote:My machine shop recommended that I 0-ring my block w/ the cometic. I looked up headgaskets on many forums and that is a good alternative to make sure you have an effective seal.
Not saying it wouldn't work sincr ive nrver tried but you typically use copper gaskets when you o ring not cometic.copper compresses around the ring to create a seal the steel isn't as soft as copper so it doesn't compress around the rings as well.if I were to try o ring and cometic I would use copper o rings so at least the ring would compress against the gasket.
New turbo setup build in progress-11mm headstuds/cometic head gasket/jwt cam gears added,prec. 6266,gato mani,prec.46mm wg,bigger fmic,mspnp2,z32 trans,spec twin,q45 rear,full energy bushings. Still need injectors,and a few other small things

Old setup-ka24de-wiseco 9:1 pistons,eagle rods,arp studs,jwt s1 cams,brian crower springs and retainers,jgs log mani,t3 57trim .63 a/r,tomei 740cc,38mm turbonetics evolution wastegate,synapse bov,ebay fmic,nistune,j30 lsd.5 speed swap,z32 brakes F&R.

drunknmunky
Knows Some Stuff About 240's!
Posts: 448
Joined: Sat Oct 08, 2005 2:13 pm

Re: cometic leaking, *i've searched*

Post by drunknmunky » Fri Jul 05, 2013 2:15 pm

I have a fwd ka buddy that went with the 90mm cometic and the o-ring'd the head. don't hear him having major issues and the car gets abused real bad @ the strip.

prokronic36
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Re: cometic leaking, *i've searched*

Post by prokronic36 » Mon Jul 15, 2013 2:31 pm

RESOLVED.

retorqed the arp nuts and the cometic gasket to fsm specs. including the loosening part and the 91 degree turn. not leaking oil at all now. got more problems having it idle, but that's for another post.

thanks for the input even though i didn't use any of it lol.

Grant
Driving Mom's Station Wagon
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Location: jacksonville

Re: cometic leaking, *i've searched*

Post by Grant » Mon Jul 15, 2013 3:27 pm

prokronic36 wrote:RESOLVED.

retorqed the arp nuts and the cometic gasket to fsm specs. including the loosening part and the 91 degree turn. not leaking oil at all now. got more problems having it idle, but that's for another post.

thanks for the input even though i didn't use any of it lol.

glad all it needed was a re torque man

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eazye2000
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Re: *resolved* cometic leaking, *i've searched*

Post by eazye2000 » Mon Jul 15, 2013 4:18 pm

For anyone searching and coming across this, I recommend torquing to FSM torqe but going in 5 or 6 steps.

Like, go in sequence all the way around to 20 ft/lbs, then to 35, then to 50, then to 65, then to 70 or 78 or whatever the FSM is (i really hate to leave this important info out)

But i've done it every time I've installed a cometic and I've never had a problem with one leaking. I've done with and without copper spray and all that jazz. I've done with and without machining surfaces. But as stated above, it's probably a good idea to get both surfaces machined with appropriate covers and do it that way.

Sorry, just got back on here and wanted badly to communicate my $.02 :mrgreen:
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Grant
Driving Mom's Station Wagon
Posts: 39
Joined: Tue May 28, 2013 12:09 pm
Location: jacksonville

Re: *resolved* cometic leaking, *i've searched*

Post by Grant » Tue Jul 16, 2013 4:54 am

eazye2000 wrote:For anyone searching and coming across this, I recommend torquing to FSM torqe but going in 5 or 6 steps.

Like, go in sequence all the way around to 20 ft/lbs, then to 35, then to 50, then to 65, then to 70 or 78 or whatever the FSM is (i really hate to leave this important info out)

:mrgreen:

this is great advice man! sometimes ppl forgoet the little thing like this and just torque it to spec.

arob987
Knows Some Stuff About 240's!
Posts: 320
Joined: Mon Feb 16, 2009 5:48 pm
Location: memphis,tn

Re: *resolved* cometic leaking, *i've searched*

Post by arob987 » Tue Jul 16, 2013 7:14 am

To the op glad you got it fixed easily.

And to comment on what eazye said that is exactly how I have done all my head gaskets wit success.this is the prop per way to torque the head.I've never had to retorque.

Just so its known for anyone searching, there is a difference in retorqing to specs and over tourqing to try and make something seal.proper tourqing is the key the first time cause a cometic doesn't compress like OEM type gaskets so retorque shouldn't be nessesary if done properly the threads are broken in/seated during install.I've never retorqued on a felpro either with the method eazye mentioned and I've torn down the same engine before checked the torque still where I set it at the first time after 10k miles
New turbo setup build in progress-11mm headstuds/cometic head gasket/jwt cam gears added,prec. 6266,gato mani,prec.46mm wg,bigger fmic,mspnp2,z32 trans,spec twin,q45 rear,full energy bushings. Still need injectors,and a few other small things

Old setup-ka24de-wiseco 9:1 pistons,eagle rods,arp studs,jwt s1 cams,brian crower springs and retainers,jgs log mani,t3 57trim .63 a/r,tomei 740cc,38mm turbonetics evolution wastegate,synapse bov,ebay fmic,nistune,j30 lsd.5 speed swap,z32 brakes F&R.

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