[DeTomaso] Cylinder Heads leaking

Brian Dudley bd8134 at gmail.com
Fri Nov 20 21:06:36 EST 2015


3% is good, 10 - 15% is rebuild time, but you are also comparing one
cylinder to another.
You would also use a higher pressure, 80 - 100 psi.
You might push the piston down which is why Larry mentioned locking the
flywheel.
Increase the pressure and use a hose to your ear to trace the noise.
You expect most air coming from past the pistons. It might be hard to hear
if you have the rocker covers off.
Maybe fit those back on for now.

On Fri, Nov 20, 2015 at 8:58 PM, sean mundy <seanmundy at hotmail.com> wrote:

> I have a compression tester but not a leakdown.
> Do you know what pressure drop I should show on a leakdown test?
> I tried lightly tapping the valves but it didn't make a difference.  I'm
> only pushing 30psi in there. I sprayed some oil around the spark plug hole
> to verify my air connection was tight which it is.  It's hard to tell where
> the hissing leak is coming from with the engine in the car.  It sounds like
> its coming from right in the middle of the engine.
> My hearing isn't quite what it used to be unfortunately.
>
> ------------------------------
> Date: Fri, 20 Nov 2015 20:34:06 -0500
> Subject: Re: [DeTomaso] Cylinder Heads leaking
> From: bd8134 at gmail.com
> To: Larry at ohiotimecorp.com
> CC: seanmundy at hotmail.com; ehpantera at yahoo.com; mikeldrew at aol.com;
> detomaso at poca.com
>
> It might help to get a leak down tester to see how bad the leak is, a
> certain amount of leakage is allowable.
> You don't say if you get the same amount of leakage from the other
> cylinders.
> Were you burning oil before you fitted the heads?
> Depending on where you piston is on its stroke you can tap on the top of
> the valve.
> Doing this allows the valve to reseat itself, you sometimes get deposits
> not allowing the valve to seal properly against its seat.
> A leak down tester is no use for detecting bad valve seals though.
>
> On Fri, Nov 20, 2015 at 8:20 PM, Larry - Ohio Time <Larry at ohiotimecorp.com
> > wrote:
>
> Hi Sean,
>
> If you hear air around the carb it is the intake valve leaking.
> If you hear air around the exhaust it is the exhaust valve leaking.
> If you see air in the radiator it is a crack or head gasket.
> If you hear air around the crank case it is the rings.
>
> You should bring the piston up to top dead center and lock the flywheel
> down
> and test it that way as the rings may seal better on top of the bore.
>
> Larry (uses a leak down tester) - Cleveland
>
>
>
>
>
> -----Original Message-----
> From: DeTomaso [mailto:detomaso-bounces at poca.com] On Behalf Of sean mundy
> Sent: Friday, November 20, 2015 8:03 PM
> To: mark skwarek; mikeldrew at aol.com
> Cc: detomaso at poca.com
> Subject: Re: [DeTomaso] Cylinder Heads leaking
>
> I tried pumping air into 7 and 8 spark plug holes and both I can hear air
> leaking.  I have all my rockers removed on that side so all the valves
> should be closed.  I've tried a few different types of gaskets but buying
> the CHI specific ones seemed to be the best approach.  They fit perfect so
> I
> hoped my valve seals were the problem especially since there is a lot of
> blue smoke on startup after the car has been sitting awhile.  I re torqued
> the heads thinking the air leak could only be either the valves or a
> leaking
> head gasket.  I have no signs of coolant in my oil.  Maybe I have multiple
> problems ?
>
> Date: Sat, 21 Nov 2015 00:52:12 +0000
> From: ehpantera at yahoo.com
> To: seanmundy at hotmail.com; mikeldrew at aol.com
> CC: detomaso at poca.com
> Subject: Re: [DeTomaso] Cylinder Heads leaking
>
> I just buy a roll of gasket material and cut my own. Never any leaks and
> easy to do.Mark
>
>
>     On Friday, November 20, 2015 7:30 PM, sean mundy <
> seanmundy at hotmail.com>
> wrote:
>
>
>     Thank you Mike.  That explains a possible oil leak being sucked in via
> a leak but that wouldn't account for me hearing air leaking when   pumping
> air into the cylinder with both valves closed?   I have CHI   heads and CHI
> intake and I'm using their specific intake gasket set. I   don't think the
> stock gasket is going to match up all that well.   > CC: detomaso at poca.com
> > From: MikeLDrew at aol.com   > Subject: Re: [DeTomaso] Cylinder Heads
> leaking
> > Date: Fri, 20 Nov 2015 16:12:19 -0800   > To: seanmundy at hotmail.com   >
> > Sean,   >   > This is a VERY common problem. Your intake manifold gasket
> has failed   and is leaking on the bottom edge, allowing oil to be sucked
> from the   valley under the intake into one or more cylinders.   >   > Many
> people have made the mistake of using Fel-Pro 'Print-o-seal'   intake
> gaskets. These things are notorious for failing; so much so that   you can
> find numerous references to them on Internet forums for all   sorts of
> cars,
> where they are commonly called 'Print-o-leak' gaskets!   >   > I happen to
> favor the stock-style valley pan gasket, Fel pro MS96012.   If you follow
> the installation instructions to the letter, these seal   fine with the
> added advantage of cooling the underside of the intake by   shielding it
> from oil splash.   >   > There is a story with photos about this chronic
> problem in a recent   PCNC newsletter; you can read it by accessing the
> website at   www.panteraclubnorcal.com   >   > I've helped repair two
> local
> cars with this problem in the past few   months and know of a third that is
> awaiting repair....   >   > Mike   >   >   >   > Sent from my iPhone   >
>  >
> On Nov 20, 2015, at 15:42, sean mundy <seanmundy at hotmail.com> wrote:   >
>  >
> > After a long hiatus, I am back working on my Pantera. Latest issue   is
> > > the engine is burning oil at about a quart every 300 miles.   > > My
> spark plugs don't look horrible but something is going on. I re   > >
> torqued the cylinder heads and intake manifold and made sure my pc   > >
> valve was working. I looked at my intake valves with an   > > inspection
> camera and there is a lot of carbon buildup but I only   have   > > about
> 2k
> miles on the new aluminum heads. I thought my valve seals   may   > > be
> leaking so I started removing the rockers on one side and tried   to   > >
> replace the Teflon valve seals on #8cyl with new Comp Cam Viton   seals.
>  >
> > I connected compressed air to the #8 spark plug hole to hold the   valve
> > > up so I could remove the spring. I don't think you are supposed to   >
> >
> but I can hear air leaking from somewhere inside the engine. It   seems   >
> > like I can feel a little air coming out of the top of the intake   > >
> manifold with my carb removed. I can't trace the air leak.   > > Need some
> tips on what steps I should take at this point. Thanks,   Sean   > >
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-------------- next part --------------
   3% is good, 10 - 15% is rebuild time, but you are also comparing one
   cylinder to another.
   You would also use a higher pressure, 80 - 100 psi.
   You might push the piston down which is why Larry mentioned locking the
   flywheel.
   Increase the pressure and use a hose to your ear to trace the noise.
   You expect most air coming from past the pistons. It might be hard to
   hear if you have the rocker covers off.
   Maybe fit those back on for now.

   On Fri, Nov 20, 2015 at 8:58 PM, sean mundy <[1]seanmundy at hotmail.com>
   wrote:

   I have a compression tester but not a leakdown.A
   Do you know what pressure drop I shouldA show on a leakdown test?
   I tried lightlyA tapping theA valvesA but it didn't make a
   difference.A  I'm only pushing 30psi in there.A I sprayed some oil
   around the spark plug hole toA verify my air connection was tight which
   it is.A  It's hard to tell where the hissing leak is coming from with
   the engine in the car.A  It sounds like its coming fromA right in the
   middle of the engine.A
   My hearing isn't quite what it used to beA unfortunately.
   A
     __________________________________________________________________

   Date: Fri, 20 Nov 2015 20:34:06 -0500
   Subject: Re: [DeTomaso] Cylinder Heads leaking
   From: [2]bd8134 at gmail.com
   To: [3]Larry at ohiotimecorp.com
   CC: [4]seanmundy at hotmail.com; [5]ehpantera at yahoo.com;
   [6]mikeldrew at aol.com; [7]detomaso at poca.com
   It might help to get a leak down tester to see how bad the leak is, a
   certain amount of leakage is allowable.
   You don't say if you get the same amount of leakage from the other
   cylinders.
   Were you burning oil before you fitted the heads?
   Depending on where you piston is on its stroke you can tap on the top
   of the valve.A
   Doing this allows the valve to reseat itself, you sometimes get
   deposits not allowing the valve to seal properly against its seat.A
   A leak down tester is no use for detecting bad valve seals though.
   On Fri, Nov 20, 2015 at 8:20 PM, Larry - Ohio Time
   <[8]Larry at ohiotimecorp.com> wrote:

     Hi Sean,
     If you hear air around the carb it is the intake valve leaking.
     If you hear air around the exhaust it is the exhaust valve leaking.
     If you see air in the radiator it is a crack or head gasket.
     If you hear air around the crank case it is the rings.
     You should bring the piston up to top dead center and lock the
     flywheel down
     and test it that way as the rings may seal better on top of the
     bore.
     Larry (uses a leak down tester) - Cleveland
     -----Original Message-----
     From: DeTomaso [mailto:[9]detomaso-bounces at poca.com] On Behalf Of
     sean mundy
     Sent: Friday, November 20, 2015 8:03 PM
     To: mark skwarek; [10]mikeldrew at aol.com
     Cc: [11]detomaso at poca.com
     Subject: Re: [DeTomaso] Cylinder Heads leaking
     I tried pumping air into 7 and 8 spark plug holes and both I can
     hear air
     leaking.A  I have all my rockers removed on that side so all the
     valves
     should be closed.A  I've tried a few different types of gaskets but
     buying
     the CHI specific ones seemed to be the best approach.A  They fit
     perfect so I
     hoped my valve seals were the problem especially since there is a
     lot of
     blue smoke on startup after the car has been sitting awhile.A  I re
     torqued
     the heads thinking the air leak could only be either the valves or a
     leaking
     head gasket.A  I have no signs of coolant in my oil.A  Maybe I have
     multiple
     problems ?
     Date: Sat, 21 Nov 2015 00:52:12 +0000
     From: [12]ehpantera at yahoo.com
     To: [13]seanmundy at hotmail.com; [14]mikeldrew at aol.com
     CC: [15]detomaso at poca.com
     Subject: Re: [DeTomaso] Cylinder Heads leaking
     I just buy a roll of gasket material and cut my own. Never any leaks
     and
     easy to do.Mark
     A  A  On Friday, November 20, 2015 7:30 PM, sean mundy
     <[16]seanmundy at hotmail.com>
     wrote:
     A  A  Thank you Mike.A  That explains a possible oil leak being
     sucked in via
     a leak but that wouldn't account for me hearing air leaking whenA
     A pumping
     air into the cylinder with both valves closed?A  A I have CHIA
     A heads and CHI
     intake and I'm using their specific intake gasket set. IA  A don't
     think the
     stock gasket is going to match up all that well.A  A > CC:
     [17]detomaso at poca.com
     > From: [18]MikeLDrew at aol.comA  A > Subject: Re: [DeTomaso] Cylinder
     Heads leaking
     > Date: Fri, 20 Nov 2015 16:12:19 -0800A  A > To:
     [19]seanmundy at hotmail.comA  A >
     > Sean,A  A >A  A > This is a VERY common problem. Your intake
     manifold gasket
     has failedA  A and is leaking on the bottom edge, allowing oil to be
     sucked
     from theA  A valley under the intake into one or more cylinders.A
     A >A  A > Many
     people have made the mistake of using Fel-Pro 'Print-o-seal'A
     A intake
     gaskets. These things are notorious for failing; so much so thatA
     A you can
     find numerous references to them on Internet forums for allA
     A sorts of cars,
     where they are commonly called 'Print-o-leak' gaskets!A  A >A  A > I
     happen to
     favor the stock-style valley pan gasket, Fel pro MS96012.A  A If you
     follow
     the installation instructions to the letter, these sealA  A fine
     with the
     added advantage of cooling the underside of the intake byA
     A shielding it
     from oil splash.A  A >A  A > There is a story with photos about this
     chronic
     problem in a recentA  A PCNC newsletter; you can read it by
     accessing the
     website atA  A [20]www.panteraclubnorcal.comA  A >A  A > I've helped
     repair two local
     cars with this problem in the past fewA  A months and know of a
     third that is
     awaiting repair....A  A >A  A > MikeA  A >A  A >A  A >A  A > Sent
     from my iPhoneA  A >A  A >
     On Nov 20, 2015, at 15:42, sean mundy <[21]seanmundy at hotmail.com>
     wrote:A  A >A  A >
     > After a long hiatus, I am back working on my Pantera. Latest
     issueA  A is
     > > the engine is burning oil at about a quart every 300 miles.A
     A > > My
     spark plugs don't look horrible but something is going on. I reA
     A > >
     torqued the cylinder heads and intake manifold and made sure my pcA
     A > >
     valve was working. I looked at my intake valves with anA  A > >
     inspection
     camera and there is a lot of carbon buildup but I onlyA  A haveA
     A > > about 2k
     miles on the new aluminum heads. I thought my valve sealsA  A mayA
     A > > be
     leaking so I started removing the rockers on one side and triedA
     A toA  A > >
     replace the Teflon valve seals on #8cyl with new Comp Cam VitonA
     A seals.A  A >
     > I connected compressed air to the #8 spark plug hole to hold theA
     A valve
     > > up so I could remove the spring. I don't think you are supposed
     toA  A > >
     but I can hear air leaking from somewhere inside the engine. ItA
     A seemsA  A >
     > like I can feel a little air coming out of the top of the intakeA
     A > >
     manifold with my carb removed. I can't trace the air leak.A  A > >
     Need some
     tips on what steps I should take at this point. Thanks,A  A SeanA
     A > >
     _______________________________________________A  A > >A  A > >
     Detomaso Forum
     Managed by POCAA  A > > Posted emails must not exceed 1.5
     MegabytesA  A > >
     DeTomaso mailing listA  A > > [22]DeTomaso at poca.comA  A > >
     [23]http://poca.com/mailman/listinfo/detomaso_poca.comA  A > >A  A >
     > To manage
     your subscription (change email address, unsubscribe,A  A etc.) use
     the links
     above.
     _______________________________________________Detomaso Forum
     Managed by
     POCAPosted emails must not exceed 1.5 MegabytesDeTomaso mailing
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     oca.comTo
     manage your subscription (change email address, unsubscribe, etc.)
     use the
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References

   1. mailto:seanmundy at hotmail.com
   2. mailto:bd8134 at gmail.com
   3. mailto:Larry at ohiotimecorp.com
   4. mailto:seanmundy at hotmail.com
   5. mailto:ehpantera at yahoo.com
   6. mailto:mikeldrew at aol.com
   7. mailto:detomaso at poca.com
   8. mailto:Larry at ohiotimecorp.com
   9. mailto:detomaso-bounces at poca.com
  10. mailto:mikeldrew at aol.com
  11. mailto:detomaso at poca.com
  12. mailto:ehpantera at yahoo.com
  13. mailto:seanmundy at hotmail.com
  14. mailto:mikeldrew at aol.com
  15. mailto:detomaso at poca.com
  16. mailto:seanmundy at hotmail.com
  17. mailto:detomaso at poca.com
  18. mailto:MikeLDrew at aol.com
  19. mailto:seanmundy at hotmail.com
  20. http://www.panteraclubnorcal.com/
  21. mailto:seanmundy at hotmail.com
  22. mailto:DeTomaso at poca.com
  23. http://poca.com/mailman/listinfo/detomaso_poca.com
  24. http://poca.com/mailman/listinfo/detomaso_poca.comTo
  25. mailto:DeTomaso at poca.com
  26. http://poca.com/mailman/listinfo/detomaso_poca.com


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