[DeTomaso] Unhappy motor - looking for suggestions

doug351c doug351c at gmail.com
Thu Nov 6 20:44:58 EST 2014


Charlie,

You can't tell if your distributor pin has failed by trying to turn the
distributor cap or the rotor by hand.

The distibutor cap and body are held fast to the engine block by the
distributor clamp/bolt under the distributor body.  If you remove this
clamp's bolt, the distributor body will be free to turn which is how you set
your timing.

The distributor's main shaft drives the oil pump so even if the pin is
sheared, the shaft is prevented from being hand-turned by the rotor.  The
rotor may feel like its turning if you try it but what you'll be feeling is
the mechanical spark advance mechanism which lies between the rotor and the
distributor main shaft.  The advance mechanism will only let you turn the
rotor about 10 degrees back and forth.

The best way to know for sure if your roll pin is bad is to take the
distributor out, drive the pin out of the gear, and inpect it.  But you'd
better know how to static time your car or let someone else do it who knows
how.

If the rotor is turning when you crank it, you can at least check for spark
as follows:
  Put the cap back on.
  Remove one of the rear spark plugs.
  Reconnect its plug wire.
  Use an insulated pliers to hold the plug's ground electrode against one of
the engine's bolts.
  Have someone crank the engine via the key.
  Look at the plug and see if you're gettting spark.

Doug Braun
blue 73L #5505

-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at poca.com]On Behalf Of Charles
McCall
Sent: Thursday, November 06, 2014 11:17 AM
To: 'Larry - Ohio Time'; janne at maki-petaja.fi; detomaso at poca.com
Subject: Re: [DeTomaso] Unhappy motor - looking for suggestions


Larry - my first thought was a flaky accelerator pump on the carb, since one
of the symptoms was stumbling upon opening the throttle. The pump pumps ,so
I guess that is eliminated.

Another suggestion from the Crowd was that my shear pin had partially
sheared and my timing was slightly off. I suppose that this is another
reasonable possibility. Hence my question if there is a way to check this
without a timing light, since I don't have one.

-----Original Message-----
From: Larry - Ohio Time [mailto:Larry at ohiotimecorp.com]
Sent: jueves, 6 de noviembre de 2014 20:12
To: 'Charles McCall'; janne at maki-petaja.fi; detomaso at poca.com
Subject: RE: [DeTomaso] Unhappy motor - looking for suggestions

Charlie,

If you still had points you could do a static timing, but you need to get a
light.

The cap being loose or tight has nothing to do with the dis pin.

I think you were talking about the accelerator pump on the carb??

Larry - Cleveland



-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at poca.com] On Behalf Of Charles
McCall
Sent: Thursday, November 06, 2014 1:42 PM
To: janne at maki-petaja.fi; detomaso at poca.com
Subject: Re: [DeTomaso] Unhappy motor - looking for suggestions

Hi all
My power valve injects fuel as it should, so that's one possible cause
eliminated.

I don't have a timing light - are there any tricks to see if my timing has
shifted without a timing light?

If my shear pin is starting to fail, would I be able to move the distributor
cap back and forth, or really only if it has catastrophically failed?

-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at poca.com] On Behalf Of Janne
Mäki-Petäjä
Sent: martes, 4 de noviembre de 2014 7:29
To: detomaso at poca.com
Subject: Re: [DeTomaso] Unhappy motor - looking for suggestions

I'd first suspect the electricals as well. It should start normally with
the gas in the fuel bowls. Easy to check the primary bowl fuel level though.

Water in the dizzy cap, or plug wire(s) gone bad would be good first
steps. Plug wire resistance is easily measured with multimeter.
I've had similar weird MSD problem once, when the distributor wire had
been laying on the block and worn through the insulator. Grounded the
dizzy signal occasionally, when it moved around.

-Janne

3.11.2014 16.09, michael at michaelshortt.com kirjoitti:
>     Water in the dist cap sounds more likely.
>
>     Michael
>
>     On Nov 3, 2014 8:48 AM, "Charles McCall" <[1]charlesmccall at gmail.com>
>     wrote:
>
>       A  A Thanks Jeff. It isn't unusually humid here and the car is
>       always stored
>       A  A indoors. As I was writing this, however, it occured to me that
>       it isn't
>       A  A imposible that some wA!ter may have entered the air cleaner and
>       dropped
>       A  A into the carb while washing the car. I'm usually pretty careful
>       with
>       A  A where I aim the hose, but I couldn't swear that the engine
>       stayed dry,
>       A  A or when opening the decklid when wet, some wA!ter may have run
>       off near
>       A  A the cleaner...
>       A  A A
>       A  A I will take the air cleaner off and see if I see a healthy
>       squirt from
>       A  A the acclerator pump. I don't think it would be fuel pump or
>       clogged
>       A  A fuel filter, as it stumbles under trailing throttle as well, it
>       it can
>       A  A provide enough fuel for sustainted 115mph running
>       A  A A
>       A  A Could it be electrical? My last MSD 6AL gave some really weird
>       symptoms
>       A  A that I thought were carb-related before I changed the box and
>       all my
>       A  A problems went away. I'll go step-by-step
>       A  A On Mon, Nov 3, 2014 at 12:55 AM, <[1][2]jgkrenton at comcast.net>
>       wrote:
>       A  A Charlie:
>       A  A How's the weather??
>       A  A Your problem sort of sounds like it could be water in the fuel
>       to me.A
>       A  A Just a drop can be a problem and once you get it in there, it
>       can hang
>       A  A around a long time.A
>       A  A As already mentioned, do the usual things to make sure you
>       didn't
>       A  A "introduce" the problem during the recent tuning.AA  Take the
>       air
>       A  A cleaner off and see if that makes any difference.AA  Check the
>       timing
>       A  A (yes, a pain on the Pantera). Make sure the accelerator pump is
>       A  A squirting. Check the fuel pressure/fuel pump etc.AA  I have
>       also been
>       A  A recently bit by a bad coil and a bad fuel pump.AA  Don't rule
>       anything
>       A  A out.
>       A  A Then dump some "fuel dryer" in the tank and run it a bit to see
>       if that
>       A  A helps.AA  Here in Seattle, water in the fuel is a common
>       problem.
>       A  A The fuel dryer should help, but there is also the tried and
>       true "rag
>       A  A tune".
>       A  A You have to be careful with this one, but the idea is to rev
>       the engine
>       A  A a bit by hand with the air cleaner off.A AA  Then when the
>       engine is
>       A  A reving a bit, maybe 2500 RPM, shove a big rag over the carb for
>       just a
>       A  A second. (The air-horns, choke, secondary venturies will keep
>       the rag
>       A  A from being sucked into the engine). The rag acts like a massive
>       choke
>       A  A and the engine will smoke and die if you leave the rag there
>       for more
>       A  A than a few seconds.AA  But what this does is raise the full
>       engine
>       A  A vacuum up above the throttle plates and jets/ bleeds to the
>       A  A air-horn/rag level.AA  This "extra" vacuum will draw any water
>       out of
>       A  A the jets/bleeds where the "normal" vacuum often is not strong
>       enough to
>       A  A pull any water out of the jets.
>       A  A If your carb is a Holley, you can pull the float chambers off
>       too and
>       A  A make sure they don't have water in them....
>       A  A Good luck.
>       A  A Jeff/2467
>       A  A
>       A __________________________________________________________________
>       A  A From: "McCall, Charles" <[2][3]charlesmccall at gmail.com>
>       A  A To: "Mark Charlton" <[3][4]pantera01826 at rogers.com>
>       A  A Cc: "DeTomaso Mail List" <[4][5]detomaso at poca.com>
>       A  A Sent: Sunday, November 2, 2014 11:46:48 AM
>       A  A Subject: Re: [DeTomaso] Unhappy motor - looking for suggestions
>       A  A Thanks Mark, but I used 3 full tanks of gas in the past 2 days
>       :-o
>       A  A The problem has gotten slowly worse, I think.
>       A  A -----Original Message-----
>       A  A From: Mark Charlton [mailto:[5][6]pantera01826 at rogers.com]
>       A  A Sent: domingo, 2 de noviembre de 2014 20:43
>       A  A To: Charles McCall
>       A  A Cc: DeTomaso Mail List
>       A  A Subject: Re: [DeTomaso] Unhappy motor - looking for suggestions
>       A  A Charlie,
>       A  A I had a very similar experience with my car during a long tour
>       in
>       A  A western
>       A  A Canada. We checked everything and concluded it must be a carb
>       issue.
>       A  A After a
>       A  A full tear-down of the carb revealed nothing wrong at all, I
>       filled the
>       A  A car
>       A  A (it was 3/4 empty) and the car ran fine again. We concluded
>       that a
>       A  A stale
>       A  A batch of 94 octane gas (not commonly available) caused the
>       issue. With
>       A  A any
>       A  A luck that will be your case too I hope.
>       A  A Mark Charlton
>       A  A [6][7]pantera01826 at rogers.com
>       A  A On Nov 2, 2014, at 2:20 PM, Charles McCall
>       <[7][8]charlesmccall at gmail.com>
>       A  A wrote:
>       A  A > I haven't checked timing, but wouldn't that make the engine
>       run hot?
>       A  A >
>       A  A > Would that explain the stumble? It might explain why it
>       doesn't feel
>       A  A as
>       A  A > crisp as it should
>       A  A >
>       A  A > -----Original Message-----
>       A  A > From: thomas [mailto:[8][9]thomas at hax.se]
>       A  A > Sent: domingo, 2 de noviembre de 2014 20:18
>       A  A > To: Charles McCall
>       A  A > Cc: <[9][10]detomaso at poca.com>
>       A  A > Subject: Re: [DeTomaso] Unhappy motor - looking for
>       suggestions
>       A  A >
>       A  A > The distributor gear pin?
>       A  A >
>       A  A > Checked timing?
>       A  A >
>       A  A >
>       A  A >> 2 nov 2014 kl. 20:13 skrev Charles McCall
>       A  A <[10][11]charlesmccall at gmail.com>:
>       A  A >>
>       A  A >> A Hi all
>       A  A >>
>       A  A >>
>       A  A >> A I just got back from a Supercar event in northern Spain
>       with 35
>       A  A cars
>       A  A >> A attending - Lambo, Ferrari, Viper, Porsche, and, as usual,
>       a lone
>       A  A >> A DeTomaso!
>       A  A >>
>       A  A >>
>       A  A >> A The highlight for me without a doubt was an 8-minute burst
>       on the
>       A  A >> A highway with the police clearing the way for us, cruising
>       at a
>       A  A steady
>       A  A >> A GPS-indicated 180 k/hr in a 35 car convoy... the people
>       out for a
>       A  A >> A Sunday drive must have had their minds boggled...
>       A  A >>
>       A  A >>
>       A  A >> A Anyway, my engine is not happy. This morning in the hotel
>       parking
>       A  A lot I
>       A  A >> A really thought that we'd have to skip today's event
>       because it
>       A  A wouldn't
>       A  A >> A start and didn't sound like it was even thinking about
>       starting.
>       A  A Took
>       A  A >> A probably 5 minutes of crank-wait-crank-wait before it
>       fired.
>       A  A Yesterday
>       A  A >> A at the gas station it took 2-3 minutes to start, something
>       that
>       A  A has
>       A  A >> A never, ever happened before. It is really hard to describe
>       the
>       A  A problem
>       A  A >> A so much of it is "feel", but I'll do my best.
>       A  A >>
>       A  A >>
>       A  A >> A A few weeks ago I noticed that the engine would tend to
>       stumble if
>       A  A I
>       A  A >> A would floor the throttle, then clear its throat and pull.
>       For
>       A  A example,
>       A  A >> A I like to heel-and-toe, just because, and when blipping
>       the
>       A  A throttle it
>       A  A >> A would stumble instead of rev. The engine also felt a
>       little
>       A  A rougher, as
>       A  A >> A though it vibrated more than I remembered it. I don't
>       remember if
>       A  A this
>       A  A >> A was before or after I did a short tune-up, by adjusting
>       the valve
>       A  A lash
>       A  A >> A (I have mechanical lifters), and cleaning the K&N air
>       filter by
>       A  A >> A applying K&N filter oil, etc. or if it is irrelevant. So I
>       was
>       A  A messing
>       A  A >> A around in the engine bay recently...
>       A  A >>
>       A  A >>
>       A  A >> A This weekend the engine felt considerably worse. It felt
>       like it
>       A  A would
>       A  A >> A stumble under partial throttle as well. It would stumble a
>       little
>       A  A bit
>       A  A >> A under trailing throttle going downhill as well, so I don't
>       think
>       A  A it is
>       A  A >> A a clogged fuel filter.
>       A  A >>
>       A  A >>
>       A  A >> A Oil temp is perfect. Oil pressure is perfect. Water temp
>       is
>       A  A perfect.
>       A  A >> A The engine idles perfectly. But if you floor the gas from
>       idle,
>       A  A it'll
>       A  A >> A stall. The engine doesn't feel crisp, it feels bloated and
>       soft,
>       A  A if
>       A  A >> A that makes sense. It feels rough, and it feels like it
>       A  A occasionally
>       A  A >> A stumbles under constant throttle at highway speed. It
>       pulls hard
>       A  A when
>       A  A >> A accelerating, but I don't think as hard as it used to, or
>       as high
>       A  A (I
>       A  A >> A have a 6500 rpm limiting chip in the MSD that it used to
>       pull very
>       A  A >> A easily to).
>       A  A >>
>       A  A >>
>       A  A >> A Suggestions for where to begin looking? And other info
>       that would
>       A  A help
>       A  A >> A in troubleshooting?
>       A  A >>
>       A  A >>
>       A  A >> !DSPAM:54568258260291209923907!
>       A  A >> _______________________________________________
>       A  A >>
>       A  A >> Detomaso Forum Managed by POCA
>       A  A >>
>       A  A >> DeTomaso mailing list
>       A  A >> [11][12]DeTomaso at poca.com
>       A  A >> [12][13]http://poca.com/mailman/listinfo/detomaso_poca.com
>       A  A >>
>       A  A >>
>       A  A >> !DSPAM:54568258260291209923907!
>       A  A >
>       A  A >
>       A  A > _______________________________________________
>       A  A >
>       A  A > Detomaso Forum Managed by POCA
>       A  A >
>       A  A > DeTomaso mailing list
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>       A  A _______________________________________________
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>       A  A DeTomaso mailing list
>       A  A [15][16]DeTomaso at poca.com
>       A  A [16][17]http://poca.com/mailman/listinfo/detomaso_poca.com
>       References
>       A  A 1. mailto:[18]jgkrenton at comcast.net
>       A  A 2. mailto:[19]charlesmccall at gmail.com
>       A  A 3. mailto:[20]pantera01826 at rogers.com
>       A  A 4. mailto:[21]detomaso at poca.com
>       A  A 5. mailto:[22]pantera01826 at rogers.com
>       A  A 6. mailto:[23]pantera01826 at rogers.com
>       A  A 7. mailto:[24]charlesmccall at gmail.com
>       A  A 8. mailto:[25]thomas at hax.se
>       A  A 9. mailto:[26]detomaso at poca.com
>       A  10. mailto:[27]charlesmccall at gmail.com
>       A  11. mailto:[28]DeTomaso at poca.com
>       A  12. [29]http://poca.com/mailman/listinfo/detomaso_poca.com
>       A  13. mailto:[30]DeTomaso at poca.com
>       A  14. [31]http://poca.com/mailman/listinfo/detomaso_poca.com
>       A  15. mailto:[32]DeTomaso at poca.com
>       A  16. [33]http://poca.com/mailman/listinfo/detomaso_poca.com
>       _______________________________________________
>       Detomaso Forum Managed by POCA
>       DeTomaso mailing list
>       [34]DeTomaso at poca.com
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>
> References
>
>     1. mailto:charlesmccall at gmail.com
>     2. mailto:jgkrenton at comcast.net
>     3. mailto:charlesmccall at gmail.com
>     4. mailto:pantera01826 at rogers.com
>     5. mailto:detomaso at poca.com
>     6. mailto:pantera01826 at rogers.com
>     7. mailto:pantera01826 at rogers.com
>     8. mailto:charlesmccall at gmail.com
>     9. mailto:thomas at hax.se
>    10. mailto:detomaso at poca.com
>    11. mailto:charlesmccall at gmail.com
>    12. mailto:DeTomaso at poca.com
>    13. http://poca.com/mailman/listinfo/detomaso_poca.com
>    14. mailto:DeTomaso at poca.com
>    15. http://poca.com/mailman/listinfo/detomaso_poca.com
>    16. mailto:DeTomaso at poca.com
>    17. http://poca.com/mailman/listinfo/detomaso_poca.com
>    18. mailto:jgkrenton at comcast.net
>    19. mailto:charlesmccall at gmail.com
>    20. mailto:pantera01826 at rogers.com
>    21. mailto:detomaso at poca.com
>    22. mailto:pantera01826 at rogers.com
>    23. mailto:pantera01826 at rogers.com
>    24. mailto:charlesmccall at gmail.com
>    25. mailto:thomas at hax.se
>    26. mailto:detomaso at poca.com
>    27. mailto:charlesmccall at gmail.com
>    28. mailto:DeTomaso at poca.com
>    29. http://poca.com/mailman/listinfo/detomaso_poca.com
>    30. mailto:DeTomaso at poca.com
>    31. http://poca.com/mailman/listinfo/detomaso_poca.com
>    32. mailto:DeTomaso at poca.com
>    33. http://poca.com/mailman/listinfo/detomaso_poca.com
>    34. mailto:DeTomaso at poca.com
>    35. http://poca.com/mailman/listinfo/detomaso_poca.com
>
>
>
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>
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