[DeTomaso] Cylinder Heads leaking

Fri Nov 20 22:42:43 EST 2015

Only tried 7 and 8 cyl so far.  Been running back and forth from the garage to the pc to ask questions!!  I have a compression tester but haven't hooked it up yet.  Going to be a busy weekend of fun in the garage.
This is a newer 408c motor with low miles on it.  It always burned a little oil.  I was led to believe the rings were not seated yet and it was normal with new motor.  Then after break in and several thousand miles I was still burning oil, a lot more.  Again I took it to a shop that told me I was probably running too rich and washing the cylinders down.  I installed a A/F meter and tuned my carb to run on the lean side with cruise at 14 to 15 and drop to 11 to 12 at full throttle.   I replaced the intake gaskets 3 times looking for the answer to oil burning from the intake.  I then took the heads off and checked everything and it all looked good after I chipped and scraped all the carbon off the valves.  I pooled gas onto the underside of the cylinder heads and didn't see anything leaking from the valves at that time.  New gaskets and put it back together last winter.  I drove it a lot this summer but it was burning oil so I parked it.  Very frustrating but I really appreciate all the help from the forum.

Date: Fri, 20 Nov 2015 22:10:30 -0500
Subject: Re: [DeTomaso] Cylinder Heads leaking
From: bd8134 at gmail.com
To: seanmundy at hotmail.com
CC: byrdjf at embarqmail.com; mikeldrew at aol.com; detomaso at poca.com

Have you tried the other cylinders?Have you tried a compression test?The leaking valves would not cause your bad oil consumption.Unless the valve guides are badly worn.A wrong pushrod length can cause the rocker to push against the valve stem rather than push the valve down and quickly wear out the valve guide.Was the engine smoking before you installed the heads?

On Fri, Nov 20, 2015 at 9:59 PM, sean mundy <seanmundy at hotmail.com> wrote:

Autozone and Oreilly's don't have loaner tool leak down testers.  Harbor Freight has one for $40.
It's starting to seem like my valves are leaking.  The engine only has 4k miles since new.  Sad

Date: Fri, 20 Nov 2015 21:51:07 -0500
Subject: Re: [DeTomaso] Cylinder Heads leaking
From: bd8134 at gmail.com
To: byrdjf at embarqmail.com
CC: seanmundy at hotmail.com; mikeldrew at aol.com; detomaso at poca.com

Yep thats the style.Mine is similar to this one.http://www.amazon.com/OTC-5609-Cylinder-Leakage-Tester/dp/B0030EVL60

On Fri, Nov 20, 2015 at 9:38 PM, Joseph F. Byrd, Jr. <byrdjf at embarqmail.com> wrote:
I had to google "leak down tester".  Basically making a flow meter.  The

precision of the orifice effects the acceptable values

-----Original Message-----

From: DeTomaso [mailto:detomaso-bounces at poca.com] On Behalf Of sean mundy

Sent: Friday, November 20, 2015 21:25 PM

To: Brian Dudley

Cc: mikeldrew at aol.com; detomaso at poca.com

Subject: Re: [DeTomaso] Cylinder Heads leaking

.... is that what you use for a leakdown test?

-------------- next part --------------
   Only tried 7 and 8 cyl so far.  Been running back and forth from the
   garage to the pc to ask questions!!  I have a compression tester but
   haven't hooked it up yet.  Going to be a busy weekend of fun in the
   garage.
   This is a newer 408c motor with low miles on it.  It always burned a
   little oil.  I was led to believe the rings were not seated yet and it
   was normal with new motor.  Then after break in and several thousand
   miles I was still burning oil, a lot more.  Again I took it to a shop
   that told me I was probably running too rich and washing the cylinders
   down.  I installed a A/F meter and tuned my carb to run on the lean
   side with cruise at 14 to 15 and drop to 11 to 12 at full throttle.
   I replaced the intake gaskets 3 times looking for the answer to oil
   burning from the intake.  I then took the heads off and checked
   everything and it all looked good after I chipped and scraped all the
   carbon off the valves.  I pooled gas onto the underside of the cylinder
   heads and didn't see anything leaking from the valves at that
   time.  New gaskets and put it back together last winter.  I drove it a
   lot this summer but it was burning oil so I parked it.  Very
   frustrating but I really appreciate all the help from the forum.
     __________________________________________________________________

   Date: Fri, 20 Nov 2015 22:10:30 -0500
   Subject: Re: [DeTomaso] Cylinder Heads leaking
   From: bd8134 at gmail.com
   To: seanmundy at hotmail.com
   CC: byrdjf at embarqmail.com; mikeldrew at aol.com; detomaso at poca.com
   Have you tried the other cylinders?
   Have you tried a compression test?
   The leaking valves would not cause your bad oil consumption.
   Unless the valve guides are badly worn.
   A wrong pushrod length can cause the rocker to push against the valve
   stem rather than push the valve down and quickly wear out the valve
   guide.
   Was the engine smoking before you installed the heads?
   On Fri, Nov 20, 2015 at 9:59 PM, sean mundy <[1]seanmundy at hotmail.com>
   wrote:

   Autozone and Oreilly's don't have loaner tool leak down
   testers.  Harbor Freight has one for $40.
   It's starting to seem like my valves are leaking.  The engine only has
   4k miles since new.  Sad
     __________________________________________________________________

   Date: Fri, 20 Nov 2015 21:51:07 -0500
   Subject: Re: [DeTomaso] Cylinder Heads leaking
   From: [2]bd8134 at gmail.com
   To: [3]byrdjf at embarqmail.com
   CC: [4]seanmundy at hotmail.com; [5]mikeldrew at aol.com;
   [6]detomaso at poca.com
   Yep thats the style.
   Mine is similar to this one.
   [7]http://www.amazon.com/OTC-5609-Cylinder-Leakage-Tester/dp/B0030EVL60
   On Fri, Nov 20, 2015 at 9:38 PM, Joseph F. Byrd, Jr.
   <[8]byrdjf at embarqmail.com> wrote:

     I had to google "leak down tester".  Basically making a flow meter.
     The
     precision of the orifice effects the acceptable values
     -----Original Message-----
     From: DeTomaso [mailto:[9]detomaso-bounces at poca.com] On Behalf Of
     sean mundy
     Sent: Friday, November 20, 2015 21:25 PM
     To: Brian Dudley
     Cc: [10]mikeldrew at aol.com; [11]detomaso at poca.com
     Subject: Re: [DeTomaso] Cylinder Heads leaking
     .... is that what you use for a leakdown test?

References

   1. mailto:seanmundy at hotmail.com
   2. mailto:bd8134 at gmail.com
   3. mailto:byrdjf at embarqmail.com
   4. mailto:seanmundy at hotmail.com
   5. mailto:mikeldrew at aol.com
   6. mailto:detomaso at poca.com
   7. http://www.amazon.com/OTC-5609-Cylinder-Leakage-Tester/dp/B0030EVL60
   8. mailto:byrdjf at embarqmail.com
   9. mailto:detomaso-bounces at poca.com
  10. mailto:mikeldrew at aol.com
  11. mailto:detomaso at poca.com