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V3 Almost!

  • Thread starter Thread starter smkshw
  • Start date Start date Aug 2, 2015
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smkshw

5 Year Member
Feb 12, 2010
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#221
  • Aug 24, 2015
  • #221
mikestang63 said:
If you hear it out of the intake, oil filler then it is either a bad intake valve- If you have a bad intake gasket check around the perimiter of the lower intake as well by squirting some soapy water and looking for bubbles or hissing noise on the cylinder you are doing the test on
If you hear it out of an adjacent cylinder spark plug hole or see bubbles in the radiator then most likely a HG or cracked block
If you hear it whistling out the tailpipe then most likely exhaust valve
No air heard leaking but you see a leakdown of 20% or more- bad rings,cylinders worn

Normal to see up to 15% leakdown on a used street motor. What you dont want to see is a huge variance between cylinders.
Click to expand...
i have one more cylinder to do!?....and if i hear nothing?....so far no leaks,no bubbles,they all hold steady at 84-85 with 90 psi....thanks for info!
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Aug 24, 2015
#222
  • Aug 24, 2015
  • #222
smkshw said:
i have one more cylinder to do!?....and if i hear nothing?....so far no leaks,no bubbles,they all hold steady at 84-85 with 90 psi....thanks for info!
Click to expand...

All good news then. check around the intake for a leak spraying soapy water or penetrating oil- non flammable- or use a smoke machine to see if their is a leak. You may have an intake gasket that broke where the head and intake meet- especially if its the cheap 1250 print o seal ones.
 

smkshw

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#223
  • Aug 24, 2015
  • #223
mikestang63 said:
All good news then. check around the intake for a leak spraying soapy water or penetrating oil- non flammable- or use a smoke machine to see if their is a leak. You may have an intake gasket that broke where the head and intake meet- especially if its the cheap 1250 print o seal ones.
Click to expand...
ok....so all check out at 84-85psi....im guessing its intake leak into oil galley right!!!....only time i heard somthing was when air pushed cylinder out of top dead....re did it and its was 84 like the rest
 

smkshw

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#224
  • Aug 24, 2015
  • #224
and they all held air for as long as i did it...about a min or so
 

smkshw

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#225
  • Aug 24, 2015
  • #225
if its intake i am so relieved....!....i can start taking it appart now with ifo i got right guys?
 

stang89bidges

Advanced Member
Mar 14, 2014
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Aug 24, 2015
#226
  • Aug 24, 2015
  • #226
Did you drain all the oil to check it first?
 

smkshw

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#227
  • Aug 24, 2015
  • #227
ya...milky
 

stang89bidges

Advanced Member
Mar 14, 2014
727
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Fort Worth Texas
Aug 24, 2015
#228
  • Aug 24, 2015
  • #228
yeah then your probably ready for tear down then. good luck bro. sux diving in with no idea yet what is wrong...
 

mikestang63

SN Certified Technician
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#229
  • Aug 24, 2015
  • #229
I'm going to guess- the intake gasket shifted under boost- get a set of 1250S3 or 1262S3 depending on your port size. They have the steel rings around the ports. Use a bit of camel snot to keep the gaskets in place when you lay the head down and put a nice 1/4 bead of right stuff on the front and back china rails- let them set up for a few minutes. Cut some long threaded rod and put one in each corner where the manifold goes down into the head as a guide When you lay down the intake just finger tight all the intake bolts and then snug them up in 3 phases- 5,15,22 lb ft torque and let it sit for a few hours. Then come back and retorque all the bolts. Then you can put the upper on.
 
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smkshw

5 Year Member
Feb 12, 2010
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Aug 24, 2015
#230
  • Aug 24, 2015
  • #230
mikestang63 said:
I'm going to guess- the intake gasket shifted under boost- get a set of 1250S3 or 1262S3 depending on your port size. They have the steel rings around the ports. Use a bit of camel snot to keep the gaskets in place when you lay the head down and put a nice 1/4 bead of right stuff on the front and back china rails- let them set up for a few minutes. Cut some long threaded rod and put one in each corner where the manifold goes down into the head as a guide When you lay down the intake just finger tight all the intake bolts and then snug them up in 3 phases- 5,15,22 lb ft torque and let it sit for a few hours. Then come back and retorque all the bolts. Then you can put the upper on.
Click to expand...
ok i took the manifold off,didnt see a definitive spot where or if it was leaking,i did notice that the gasket came off real easy around the water ports,and hard to tell but it seemed to be wet behind also?....gona take a few pics in a few mins to post
 

smkshw

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#231
  • Aug 24, 2015
  • #231
@mikestang63 this is felpro 1262s-3?....am i ok to use this?
 

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smkshw

5 Year Member
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Aug 24, 2015
#232
  • Aug 24, 2015
  • #232
what was on mine was 1262 i believe with the tabs cut?
 

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smkshw

5 Year Member
Feb 12, 2010
1,095
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Aug 24, 2015
#233
  • Aug 24, 2015
  • #233
 

smkshw

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Aug 24, 2015
#234
  • Aug 24, 2015
  • #234
here are the pics....sorry somthing is glitching
this is the one that was suspect to me?....lots of coffee in that side?

 

smkshw

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#235
  • Aug 24, 2015
  • #235
 

Chuckman

GTFO you fat, heavy bastard
15 Year Member
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Aug 24, 2015
#236
  • Aug 24, 2015
  • #236
My last two pairs of 1250s3's i didn't have to cut that tab. Dunno if they changed it from an earlier version or not. That is usually where the paper ones fail though.
 

smkshw

5 Year Member
Feb 12, 2010
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Aug 24, 2015
#237
  • Aug 24, 2015
  • #237
Chuckman said:
My last two pairs of 1250s3's i didn't have to cut that tab. Dunno if they changed it from an earlier version or not. That is usually where the paper ones fail though.
Click to expand...
the 1262s3 the one at the top seems like it has very little gasket on the sides?
 

smkshw

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Aug 24, 2015
#238
  • Aug 24, 2015
  • #238
and should i use black blue or red rtv ?
 

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Aug 24, 2015
#239
  • Aug 24, 2015
  • #239
smkshw said:
Click to expand...

yep -- that is exactly where the print o seal 1250's fail. Around the water jacket. Did you put RTV around the water jacket opening, as that causes distortion to the gasket.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Aug 24, 2015
#240
  • Aug 24, 2015
  • #240
smkshw said:
and should i use black blue or red rtv ?
Click to expand...

Right Stuff

Permatex/4 oz. automatic tube the Right Stuff gasket maker 25223 at AutoZone.com
 
Reactions: stang89bidges and Noobz347
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