Startup idle-too fast

They do not all have vacuum pull-offs. At least that been my experience.
The 403 for California use has vacuum controls on the HEI as well. They are
a whole different kind of animal. Early 455's that had points ignition are
different than 76 and later 455's with HEI as well. Vacuum pull offs
basically are not for warm ups, but more for full throttle applications.
Jim Hupy
Salem,Oregon

On Thu, Oct 29, 2020, 4:17 PM Norm Bowker via Gmclist <

> All this talk about choke settings & nobody has mentioned the vacuum pull
> off. When I had my 76 El II I had the choke set after many small
> adjustments that it started & ran like it was fuel injected.
>
> Sent from my iPad stormn
>
>
> > On Oct 29, 2020, at 5:59 PM, Matt Colie via Gmclist <

> >

> >> Well I went thru the adjustments and tried to start it and it would not
> start, so I loosened the screws on the choke cover and adjusted it so the
> >> flap was nearly closed again and then tried it and it started right up.
> It did gradually start climbing in revs as it warmed up and I adjusted the
> >> idle back to roughly 1000 to 1200rpm. Seem to not stall now with a
> much shorter warmup, so it seems to have worked. I did go thru this a
> couple
> >> years ago and did notice the idle adjustment screw seemed to be a
> little loose when I adjusted it so I wonder if it simply vibrates out of
> >> adjustment over time. Any ideas to help this?
> >>
> >> Thanks,
> >> Tom
> >

> >> There should be a little spring on the screw to keep it from backing
> off.
> >> https://tinyurl.com/yycnyb7h (trying out my new tinyurl extension)
> ;)
> >>
> >> bdub
> >
> > It does not pain me at all to admit that Billy is right about this.
> Mine is missing and I didn't even know it should be there, I just fixed
> it.
> > I like the spring idea better.
> >
> > Matt
> >
> > --
> > Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> GMCES
> > Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> Brakes with Applied Control Arms
> > SE Michigan - Near DTW - Twixt A2 and Detroit
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
> GMCnet mailing list
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>
 
My 455 had a vacuum pull off on the choke (adjustable) that opened the plate slightly to prevent over choking.

Sent from my iPad stormn

>
> They do not all have vacuum pull-offs. At least that been my experience.
> The 403 for California use has vacuum controls on the HEI as well. They are
> a whole different kind of animal. Early 455's that had points ignition are
> different than 76 and later 455's with HEI as well. Vacuum pull offs
> basically are not for warm ups, but more for full throttle applications.
> Jim Hupy
> Salem,Oregon
>
>> On Thu, Oct 29, 2020, 4:17 PM Norm Bowker via Gmclist <

>>
>> All this talk about choke settings & nobody has mentioned the vacuum pull
>> off. When I had my 76 El II I had the choke set after many small
>> adjustments that it started & ran like it was fuel injected.
>>
>> Sent from my iPad stormn
>>
>>
>>> On Oct 29, 2020, at 5:59 PM, Matt Colie via Gmclist <

>>>

>>>> Well I went thru the adjustments and tried to start it and it would not
>> start, so I loosened the screws on the choke cover and adjusted it so the
>>>> flap was nearly closed again and then tried it and it started right up.
>> It did gradually start climbing in revs as it warmed up and I adjusted the
>>>> idle back to roughly 1000 to 1200rpm. Seem to not stall now with a
>> much shorter warmup, so it seems to have worked. I did go thru this a
>> couple
>>>> years ago and did notice the idle adjustment screw seemed to be a
>> little loose when I adjusted it so I wonder if it simply vibrates out of
>>>> adjustment over time. Any ideas to help this?
>>>>
>>>> Thanks,
>>>> Tom
>>>

>>>> There should be a little spring on the screw to keep it from backing
>> off.
>>>> https://tinyurl.com/yycnyb7h (trying out my new tinyurl extension)
>> ;)
>>>>
>>>> bdub
>>>
>>> It does not pain me at all to admit that Billy is right about this.
>> Mine is missing and I didn't even know it should be there, I just fixed
>> it.
>>> I like the spring idea better.
>>>
>>> Matt
>>>
>>> --
>>> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
>> GMCES
>>> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
>> Brakes with Applied Control Arms
>>> SE Michigan - Near DTW - Twixt A2 and Detroit
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Not about back tension spring on it Matt, all I can say is it felt a little loose when I adjusted it.
May go with the pink stuff if I can reach it. Have not heard of the vacuum pull off, what does that do?

Thanks,
Tom
--
Tom Geiger
76 Eleganza II
KCMO
 
So all started and warmed up well and doing its warm up at much lower idle. Saw some smoke for a bit so am wondering if I need to kick up the idle
speed more to get it not to choke out or is that with ghe choke adjustment? Other than that it did not stall after much shorter warmup so I consider
this a success!

Now since we’re in the same ballpark I want to talk about another problem I’m having. I’ve been having a slight light pedal pinging going on
that seems to happen when I’m driving highway and or doing 45-60mph going up and down on the hilly rural highways we have around KC. I get none of
this when I drive it around in traffic in town. I had this startup when a had a local mechanic do a crossover plate block with Jim K’s SS plate
kit. It really seems to show up after the engine is ran at highway speeds for a bit. I thought it was too much vacuum advance and wanted to test
that so I unplugged the v/a hose and plugged it. That hose is feeding off the right front port of the carb. So I’m running on 12d initial only and
still seem to get this. I’m starting to wonder if there is a air breach somewhere that shows up after the engine warms up? Like it starts to lean
out after it warms up to running temps. I’ve been toying with the idea of going TBI and wonder if I can remove the crossover blocking plates when
the TBI system is put in or should they stay? Thinking of removing them and resealing the intake because it seems thats when this all started. Also
had a brothers friend put on some hearing scopes and listen to the bottom end of the engine when it was running and he said he heard no problems.
Also had a oil lab analyze the oil and they said everything looked fine. So this is befuddling me. Also recently installed Springfields distributor
and Dick helped me thru that process. Anyhow its been a big frustration to resolve.

TG

--
Tom Geiger
76 Eleganza II
KCMO
 
I think your mechanical advance might be jammed.
Check to see that the rotor is free to pivit.
If that is fine, then retard the timing 2degrees and see.

On Sat, Oct 31, 2020 at 5:14 AM tom geiger via Gmclist <

> So all started and warmed up well and doing its warm up at much lower
> idle. Saw some smoke for a bit so am wondering if I need to kick up the
> idle
> speed more to get it not to choke out or is that with ghe choke
> adjustment? Other than that it did not stall after much shorter warmup so
> I consider
> this a success!
>
> Now since we’re in the same ballpark I want to talk about another problem
> I’m having. I’ve been having a slight light pedal pinging going on
> that seems to happen when I’m driving highway and or doing 45-60mph going
> up and down on the hilly rural highways we have around KC. I get none of
> this when I drive it around in traffic in town. I had this startup when a
> had a local mechanic do a crossover plate block with Jim K’s SS plate
> kit. It really seems to show up after the engine is ran at highway speeds
> for a bit. I thought it was too much vacuum advance and wanted to test
> that so I unplugged the v/a hose and plugged it. That hose is feeding off
> the right front port of the carb. So I’m running on 12d initial only and
> still seem to get this. I’m starting to wonder if there is a air breach
> somewhere that shows up after the engine warms up? Like it starts to lean
> out after it warms up to running temps. I’ve been toying with the idea of
> going TBI and wonder if I can remove the crossover blocking plates when
> the TBI system is put in or should they stay? Thinking of removing them
> and resealing the intake because it seems thats when this all started. Also
> had a brothers friend put on some hearing scopes and listen to the bottom
> end of the engine when it was running and he said he heard no problems.
> Also had a oil lab analyze the oil and they said everything looked fine.
> So this is befuddling me. Also recently installed Springfields distributor
> and Dick helped me thru that process. Anyhow its been a big frustration
> to resolve.
>
> TG
>
> --
> Tom Geiger
> 76 Eleganza II
> KCMO
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
What Jim said!

Jim Hupy
Salem, Oregon

On Sat, Oct 31, 2020, 2:37 PM Jim Kanomata via Gmclist <

> I think your mechanical advance might be jammed.
> Check to see that the rotor is free to pivit.
> If that is fine, then retard the timing 2degrees and see.
>
>
> On Sat, Oct 31, 2020 at 5:14 AM tom geiger via Gmclist <

>
> > So all started and warmed up well and doing its warm up at much lower
> > idle. Saw some smoke for a bit so am wondering if I need to kick up the
> > idle
> > speed more to get it not to choke out or is that with ghe choke
> > adjustment? Other than that it did not stall after much shorter warmup
> so
> > I consider
> > this a success!
> >
> > Now since we’re in the same ballpark I want to talk about another problem
> > I’m having. I’ve been having a slight light pedal pinging going on
> > that seems to happen when I’m driving highway and or doing 45-60mph going
> > up and down on the hilly rural highways we have around KC. I get none of
> > this when I drive it around in traffic in town. I had this startup when
> a
> > had a local mechanic do a crossover plate block with Jim K’s SS plate
> > kit. It really seems to show up after the engine is ran at highway
> speeds
> > for a bit. I thought it was too much vacuum advance and wanted to test
> > that so I unplugged the v/a hose and plugged it. That hose is feeding
> off
> > the right front port of the carb. So I’m running on 12d initial only and
> > still seem to get this. I’m starting to wonder if there is a air breach
> > somewhere that shows up after the engine warms up? Like it starts to
> lean
> > out after it warms up to running temps. I’ve been toying with the idea
> of
> > going TBI and wonder if I can remove the crossover blocking plates when
> > the TBI system is put in or should they stay? Thinking of removing them
> > and resealing the intake because it seems thats when this all started.
> Also
> > had a brothers friend put on some hearing scopes and listen to the bottom
> > end of the engine when it was running and he said he heard no problems.
> > Also had a oil lab analyze the oil and they said everything looked fine.
> > So this is befuddling me. Also recently installed Springfields
> distributor
> > and Dick helped me thru that process. Anyhow its been a big frustration
> > to resolve.
> >
> > TG
> >
> > --
> > Tom Geiger
> > 76 Eleganza II
> > KCMO
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ok Jim’s, I’ll check the mechanical advance to make sure its working, but it is a new Paterson’s distributor.
--
Tom Geiger
76 Eleganza II
KCMO
 
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