TECH: Stargate WEAK Left VUK

[Guest]

Archived from groups: rec.games.pinball (More info?)

I am having alot of trouble with the left VUK on Stargate. It was
having trouble consistently delivering the ball through the scoop and
onto the metal ramp. Replaced coil sleeve, coil, spring, cleaned
plunger and adjusted scoop slightly thinking it was hitting scoop
incorrectly. It seems to have worked well for about 3 months and now
it is again having trouble delivering the ball. It will try to deliver
the ball several times before "Ball stuck" message appears.

I have read that this VUK is king of "weak" to begin with. Is there
anything that I can do to correct and improve the performance and
reliability? The plunger head is stable - so it is not movement in the
plunger assembly causing the problem.

Has anyone been able to correct this? Different coil, different
plunger?

HELP!!!

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Unplug and replug the molex connector on the coil wires several times.
Should be about 6 inches down the wire from the coil lugs. Resistance
there can be a power killer.

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

I had a simular problem with my Jurassic Park, I solved mine by making
sure that the coil was aligned correctly. It seemed to be shooting the
ball at an angle and the ball was hitting the bottom edge of the pf
before coming up through the pf hole. After re-aligning my coil, it
now shoots the ball straight through.

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

If I'm not mistaken the plunger Gottlieb used does not have a cup like
Williams and Stern does. The alignment as mentioned in the other posts
is critical. Also the shape of the plunger tip is important. Make
sure the coil bracket at the plunger end is straight and not binding
the sleeve. Make sure the plunger end is free from mushrooming.

And one "Doh". Make sure the right coil is in the assembly. Change
the coil diode. A leaky diode can cause a loss of power, (until it
shorts finally and takes out a fuse).

Mario
Pinthetic

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Be sure the solder joints on the coil are good, then follow the wires around
to other coils, a weak or broken wire at another point could weaken your
coil. LTG

<paflys@yahoo.com> wrote in message
news:1126122763.206232.149510@o13g2000cwo.googlegroups.com...
> I am having alot of trouble with the left VUK on Stargate. It was
> having trouble consistently delivering the ball through the scoop and
> onto the metal ramp. Replaced coil sleeve, coil, spring, cleaned
> plunger and adjusted scoop slightly thinking it was hitting scoop
> incorrectly. It seems to have worked well for about 3 months and now
> it is again having trouble delivering the ball. It will try to deliver
> the ball several times before "Ball stuck" message appears.
>
> I have read that this VUK is king of "weak" to begin with. Is there
> anything that I can do to correct and improve the performance and
> reliability? The plunger head is stable - so it is not movement in the
> plunger assembly causing the problem.
>
> Has anyone been able to correct this? Different coil, different
> plunger?
>
> HELP!!!
>

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

If it is supposed to have a rubber grommet for the plunger to rest on
make sure it's there! Easy to tell. If there's a small hole in the
bottom of the bracket where the plunger rests then there should be a
grommet there. If it's missing the plunger will not be in the coil at
the right height to get a good launch pulse of magnetism.

paflys@yahoo.com wrote:
> I am having alot of trouble with the left VUK on Stargate. It was
> having trouble consistently delivering the ball through the scoop and
> onto the metal ramp. Replaced coil sleeve, coil, spring, cleaned
> plunger and adjusted scoop slightly thinking it was hitting scoop
> incorrectly. It seems to have worked well for about 3 months and now
> it is again having trouble delivering the ball. It will try to deliver
> the ball several times before "Ball stuck" message appears.
>
> I have read that this VUK is king of "weak" to begin with. Is there
> anything that I can do to correct and improve the performance and
> reliability? The plunger head is stable - so it is not movement in the
> plunger assembly causing the problem.
>
> Has anyone been able to correct this? Different coil, different
> plunger?
>
> HELP!!!
>

--
Cliffy - CARGPB2
A passion for pinball!
http://www.passionforpinball.com

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Thanks for the quick replies. In reviewing everything noted above, I
realize that the previous owner may have installed the wrong VUK
Plunger (coil is OK). I pulled out my manual and confirmed that
Gottlieb uses a straight plunger/tip assembly (21412). The plunger
that is installed in the machine has a platform similar to DE /
Williams (?) style machines. Even though it moves freely within the
coil sleeve, could it be too heavy to launch the ball correctly????

Should I order the Gottlieb version (21412)? Does this mean the ball
just lands on the double flanged coil sleeve (21411)? The Rubber
grommet is on the bottom of the bracket and the bracket looks pretty
straight.

Question regarding the metal scoop/ shield assembly: Is there a proper
way to align. How do I know whether I should reshape. Is ball suppose
to ride up the back of the scoop or does it launch straight up and hit
it somewhere in the process?

Thanks to all!! Let me know your thoughts on the plunger.

Andy


Cliffy wrote:
> If it is supposed to have a rubber grommet for the plunger to rest on
> make sure it's there! Easy to tell. If there's a small hole in the
> bottom of the bracket where the plunger rests then there should be a
> grommet there. If it's missing the plunger will not be in the coil at
> the right height to get a good launch pulse of magnetism.
>
> paflys@yahoo.com wrote:
> > I am having alot of trouble with the left VUK on Stargate. It was
> > having trouble consistently delivering the ball through the scoop and
> > onto the metal ramp. Replaced coil sleeve, coil, spring, cleaned
> > plunger and adjusted scoop slightly thinking it was hitting scoop
> > incorrectly. It seems to have worked well for about 3 months and now
> > it is again having trouble delivering the ball. It will try to deliver
> > the ball several times before "Ball stuck" message appears.
> >
> > I have read that this VUK is king of "weak" to begin with. Is there
> > anything that I can do to correct and improve the performance and
> > reliability? The plunger head is stable - so it is not movement in the
> > plunger assembly causing the problem.
> >
> > Has anyone been able to correct this? Different coil, different
> > plunger?
> >
> > HELP!!!
> >
>
> --
> Cliffy - CARGPB2
> A passion for pinball!
> http://www.passionforpinball.com

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

The ball is centered two ways on Gottlieb VUK's. The first is by the
square wireform switch actuator, 28953, and then it sits in the sleeve
opening. These are the alignment guides. The ball has to rest so the
cup of the plunger will contact it with "momentum" as it operates. If
you are using a WMS/DE type of plunger it may be a little heavy. I'm
not sure. But one thing for sure is that there will not be any
momentum of the pluger as it will have to pick up the plunger and the
ball together. If the wrong tension spring, (stronger), is used this
can cause a less forcefull activation. If you have WMS/DE parts,
replace them with Gottlieb parts, so that mechanism can work as
designed.

Mario
Pinthetic

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Ironically last night it died altogether, coil stuck in sleeve.
My approach will be:
1) new coil/ resolder all connections in daisy chain.
2) if still no good, remove playfield ramp/chute to observe trajectory.
If the height is good must be angle. I don't know which gets aligned,
scoop or VUK.

Jack James



paflys@yahoo.com wrote:
> You're right. I have the same configuration in this Stargate (optos,
> plunger with white plastic cup, green coil). Interesting that the
> manual does not show this VUK assembly. Question is how to make it
> work more consistently. After many attempts to fire the ball out it
> quits in "Ball stuck" mode. Is there a proper way to align the scoop?
> Can you upgrade the coil? -- Andy
>

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Follow up:
Replaced the dead MOSFET (12N10L)
Replaced dead fuse (27 1.5 SB)
Replaced melted coil ( 16570 ).
Scraped melted sleeve from plunger.

Have not had a single problem since without adjusting the VUK.
All the replaced items were new except the coil and diode so I will
blame one of those or possible scaping of the plunger.


John W. James wrote:
> Ironically last night it died altogether, coil stuck in sleeve.
> My approach will be:
> 1) new coil/ resolder all connections in daisy chain.
> 2) if still no good, remove playfield ramp/chute to observe trajectory.
> If the height is good must be angle. I don't know which gets aligned,
> scoop or VUK.
>
> Jack James
>
>
>
> paflys@yahoo.com wrote:
>
>> You're right. I have the same configuration in this Stargate (optos,
>> plunger with white plastic cup, green coil). Interesting that the
>> manual does not show this VUK assembly. Question is how to make it
>> work more consistently. After many attempts to fire the ball out it
>> quits in "Ball stuck" mode. Is there a proper way to align the scoop?
>> Can you upgrade the coil? -- Andy
>>
>

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

I'm looking for the part number for the plunger for the left VUK. As
the posting indicates, the manual only calls out the right and middle
VUK part numbers. Anyone have an idea of the left part number?

Someone said I should also consider using a Williams VUK plunger.
Anyone have a suggestion?

Andy

Jack James wrote:
> Follow up:
> Replaced the dead MOSFET (12N10L)
> Replaced dead fuse (27 1.5 SB)
> Replaced melted coil ( 16570 ).
> Scraped melted sleeve from plunger.
>
> Have not had a single problem since without adjusting the VUK.
> All the replaced items were new except the coil and diode so I will
> blame one of those or possible scaping of the plunger.
>
>
> John W. James wrote:
> > Ironically last night it died altogether, coil stuck in sleeve.
> > My approach will be:
> > 1) new coil/ resolder all connections in daisy chain.
> > 2) if still no good, remove playfield ramp/chute to observe trajectory.
> > If the height is good must be angle. I don't know which gets aligned,
> > scoop or VUK.
> >
> > Jack James
> >
> >
> >
> > paflys@yahoo.com wrote:
> >
> >> You're right. I have the same configuration in this Stargate (optos,
> >> plunger with white plastic cup, green coil). Interesting that the
> >> manual does not show this VUK assembly. Question is how to make it
> >> work more consistently. After many attempts to fire the ball out it
> >> quits in "Ball stuck" mode. Is there a proper way to align the scoop?
> >> Can you upgrade the coil? -- Andy
> >>
> >

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Looks my turn again on system 3's.

I think you are referring to part # 31805. I can supply a pdf of this
assembly.

Mario
Pinthetic


paflys@yahoo.com wrote:
> I'm looking for the part number for the plunger for the left VUK. As
> the posting indicates, the manual only calls out the right and middle
> VUK part numbers. Anyone have an idea of the left part number?
>
> Someone said I should also consider using a Williams VUK plunger.
> Anyone have a suggestion?
>
> Andy
>

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

I'm sorry, I gave the assembly number for the whole upkicker. The
plunger tip and cup assembly is 30463.

Mario
Pinthetic