1973 No Spark Need Instructions And Pep Talk

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I haven't started the Sequoia since sometime in late 2013, when it started right up.

Today with a charged battery and spinning fast enough to fire with a few thimbles full of gas down its throat, no fire. I thought I might have flooded
it, Peer said we should check the spark. Glad we got some intelligence on this project. I thought if the ignition system worked when I shut it down
gracefully at last run, those things should be in the same state as before. But no.

So I popped the distributor cap off and observed things that are in the way of checking the points and condenser. And there is a condenser on the side
of the coil. Is there no condenser inside the distributor?

Can someone spoon feed me the procedure for verifying that the coil is ok? Can someone spoon feed me the procedure for verifying the condenser is OK.
Can someone spoon feed me the procedure for getting to the points?

I don't mind getting a tune-up kit from the auto parts store, what put me off was the complexity of trying to get to the points in the distributor. Is
the points assembly under that metal cover under the rotor? And what can I expect trying to get the mechanical advance weights out of the way? Are
they pressed on and need a slide hammer to get them off?

I need to be talked off the ledge today. This puts us back another day in trying to get it on the road by Tuesday morning.

HELP!
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
Sir, what usually happens with points is they don't like sitting. Take the cap off and bump starter till points are closed. Key off, fold up a
dollar bill and put between the points and file back and forth to clean. Turn key on and open points by hand and see if it sparks. If it sparks it
should fire. Repeat if not. If you still don't get spark bump starter till points are open key on use screwdriver to short across the point arm and
base if spark replace points. Make sure you have voltage to the coil and the wire going to distributor and they are tight.

> I haven't started the Sequoia since sometime in late 2013, when it started right up.
>
> Today with a charged battery and spinning fast enough to fire with a few thimbles full of gas down its throat, no fire. I thought I might have
> flooded it, Peer said we should check the spark. Glad we got some intelligence on this project. I thought if the ignition system worked when I shut
> it down gracefully at last run, those things should be in the same state as before. But no.
>
> So I popped the distributor cap off and observed things that are in the way of checking the points and condenser. And there is a condenser on the
> side of the coil. Is there no condenser inside the distributor?
>
> Can someone spoon feed me the procedure for verifying that the coil is ok? Can someone spoon feed me the procedure for verifying the condenser is
> OK. Can someone spoon feed me the procedure for getting to the points?
>
> I don't mind getting a tune-up kit from the auto parts store, what put me off was the complexity of trying to get to the points in the
> distributor. Is the points assembly under that metal cover under the rotor? And what can I expect trying to get the mechanical advance weights out
> of the way? Are they pressed on and need a slide hammer to get them off?
>
> I need to be talked off the ledge today. This puts us back another day in trying to get it on the road by Tuesday morning.
>
> HELP!

--
C. Boyd
76 Crestmont
East Tennessee
 
For points first check for spark. A screwdriver in a spark plug wire and
close to metal for jumping spark. Once done crank engine. Observe the
screwdriver for spark. If weak take off dist cover and check point gap.
Make sure point gap is per specs. Use the mm measuring kit you would use
for checking valve lash. Check spec for proper gap.
Next check your rotor for corrosion and wear. If in doubt, replace.
Pertronix makes an HEI conversation kit that fits in the original dist.
I convert any vehicle I purchase to HEI. I never run points. The GM 455 HEI
drops right in too with minor wire working.
Sammy Williams
 
A.

Yes, there is a condenser in the distributor.
DO NOT try to convert to HEI. They require mechanical modification the air filter housing and are unreliable. Pertronix replacement for ignition
points are entirely reliable. And if you want more spark, add a real CDI later.

Now, I am betting with Chuck. Points don't like to be ignored. A dollar bill works on a running engine, but you might need to do the pass with some
real sand paper. Any wet-or-dry 200 or finer will do.

What I always used to do was park the engine with the points closed and open them with a screwdriver by the rubbing block and slip the sandpaper in
and pull it out a few times with the grit each way.

Now, pull the coil wire out of the distributor cap and put it near something (don't hold it in your hand). Turn the ignition on and use the
screwdriver trick to open the points. Got a Spark Now??

Do that and let us know.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Yes, the points and condenser are under that metal cover. 2 screws and it is out of your way. It is best to take the rotor off but you do not need to
remove the advance weights. the condenser sits on the same plate as the points set or, sometimes, is connected to the points. The condenser on the
coil is for noise reduction. you can disconnect it if you feel it is bad.

I agree with Chuck and Matt, it is probably corroded points. Clean them as instructed and you can set the dwell after you get it running. Also, there
may be a dirty ground and check that you have power as suggested in earlier posts.

That should get you running and you can decide what you want to do later.
--
Patti & Jerry Burt
73 Gmc 26' Canyon Lands -
Photos - http://jburt.smugmug.com/GMC-Motorhome
Lots of upgrades but lots to do to make it ours.
Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
 
While others may disagree and at least one has, Every car I have converted
to HEI has been stone cold reliable. Of course I was using new parts when I
did it. I've done it on Olds 455 and Buick 455 as well as 350 and 454
Chevy.
Of course your mileage may vary.
Sammy
 
Do you have a meter? You can Ohm the primary out of circuit, coil nut to coil nut should have some nominal reading. Then meter coil tower to case and
you should have some higher Ohms reading. Then on DCV you should have less than 12V on coil neg when point are open and drop to zero when points
close. If the points are not grounding that neg side of the coil it won't charge and spark when points open. A shorted condenser will cause a no run.
Condenser more likely to fail over winter sitting.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Sammy

HEI conversion may be the thing to do -- But, please note that Mark and Peer are trying to complete a sale so Peer can drive the coach on to Ken Frey
for extensive work. They just need to get it running for the trip.

Dennis

> While others may disagree and at least one has, Every car I have converted
> to HEI has been stone cold reliable. Of course I was using new parts when I
> did it. I've done it on Olds 455 and Buick 455 as well as 350 and 454
> Chevy.
> Of course your mileage may vary.
> Sammy
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Dennis S
73 Painted Desert 230
Memphis TN Metro
 
> Yes, the points and condenser are under that metal cover. 2 screws and it is out of your way. It is best to take the rotor off but you do not need
> to remove the advance weights. the condenser sits on the same plate as the points set or, sometimes, is connected to the points. The condenser on
> the coil is for noise reduction. you can disconnect it if you feel it is bad.
>
> I agree with Chuck and Matt, it is probably corroded points. Clean them as instructed and you can set the dwell after you get it running. Also,
> there may be a dirty ground and check that you have power as suggested in earlier posts.
>
> That should get you running and you can decide what you want to do later.
The explanation that I don't need to remove the advance weights is the answer I sought. This is the first points/condenser distributor that I have
opened up that didn't have the points and condenser accessible as soon as the cap was off.

I stopped by Oreillys this afternoon and a tune-up kit was a special order thing with 5 day wait. I will try cleaning the points, but if the condenser
is toast, I will be driving to all the other parts places tomorrow to try to get a tune-up kit.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
> > Yes, the points and condenser are under that metal cover. 2 screws and it is out of your way. It is best to take the rotor off but you do not
> > need to remove the advance weights. the condenser sits on the same plate as the points set or, sometimes, is connected to the points. The
> > condenser on the coil is for noise reduction. you can disconnect it if you feel it is bad.
> >
> > I agree with Chuck and Matt, it is probably corroded points. Clean them as instructed and you can set the dwell after you get it running.
> > Also, there may be a dirty ground and check that you have power as suggested in earlier posts.
> >
> > That should get you running and you can decide what you want to do later.
> The explanation that I don't need to remove the advance weights is the answer I sought. This is the first points/condenser distributor that I have
> opened up that didn't have the points and condenser accessible as soon as the cap was off.
>
> I stopped by Oreillys this afternoon and a tune-up kit was a special order thing with 5 day wait. I will try cleaning the points, but if the
> condenser is toast, I will be driving to all the other parts places tomorrow to try to get a tune-up kit.


You "should" be able to buy the condenser (and points) separately. I'm surprised they didn't have any, they have been used in GM V8 motors for years.

Notice, the rotor only goes on one way. There is a square and a round pin on the bottom. Since this is just a temporary fix, you don't really need to
replace the metal shields.

--
Patti & Jerry Burt
73 Gmc 26' Canyon Lands -
Photos - http://jburt.smugmug.com/GMC-Motorhome
Lots of upgrades but lots to do to make it ours.
Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
 
> You "should" be able to buy the condenser (and points) separately. I'm surprised they didn't have any, they have been used in GM V8 motors for
> years.
> Notice, the rotor only goes on one way. There is a square and a round pin on the bottom. Since this is just a temporary fix, you don't really need
> to replace the metal shields.
I first asked for a tune-up kit. That was the 5 day lead item. Then I said I needed points and condenser only. More keyboard fumbling and no clear
indication that any of the dozen or so line items on the screen were what I needed.

I didn't take the old parts with me, because I am trying not to dismantle more than I have to (the more I take apart, the harder it is going to be to
get it back together by Tuesday morning). That is the only way to get the right part - open the package and lay the old and new side by side. An
undesirable, but viable, fallback is to buy everything he has in the store, take it all home, and hope one of them is correct, and take the leftovers
back for a refund.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
You could do this: Ask for a points set/condenser for a (year of your GMC)
Oldsmobile Delta 88 with a 455. Chances are (I am guessing) Its the same
part you need for the 455 in your GMC.

Sammy

> > You "should" be able to buy the condenser (and points) separately. I'm
> surprised they didn't have any, they have been used in GM V8 motors for
> > years.
> > Notice, the rotor only goes on one way. There is a square and a round
> pin on the bottom. Since this is just a temporary fix, you don't really need
> > to replace the metal shields.
> I first asked for a tune-up kit. That was the 5 day lead item. Then I said
> I needed points and condenser only. More keyboard fumbling and no clear
> indication that any of the dozen or so line items on the screen were what
> I needed.
>
> I didn't take the old parts with me, because I am trying not to dismantle
> more than I have to (the more I take apart, the harder it is going to be to
> get it back together by Tuesday morning). That is the only way to get the
> right part - open the package and lay the old and new side by side. An
> undesirable, but viable, fallback is to buy everything he has in the
> store, take it all home, and hope one of them is correct, and take the
> leftovers
> back for a refund.
> --
> 73 23' Sequoia 4 Sale
> 73 23' CanyonLands Parts Unit 4 Sale
> Upper Alabama
> "When I grow up I am going to be a curmudgeon."
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> You could do this: Ask for a points set/condenser for a (year of your GMC)
> Oldsmobile Delta 88 with a 455. Chances are (I am guessing) Its the same part you need for the 455 in your GMC.
>
> Sammy
What's the difference between the distributor in a 1973 Delta 88 and a 1973 Toronado (which is what I asked for).
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
> ...Pertronix makes an HEI conversation kit that fits in the original dist. ...
Is this what you are talking about: http://www.appliedgmc.com/prod.itml/icOid/775

If I was going to keep and use the GMC, I would probably go that route.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"When I grow up I am going to be a curmudgeon."
 
Your ahead of me. I was thinking the "delta 88" unit would be more
accessible, as more of them were made than Toronados. :)

Sammy

> > ...Pertronix makes an HEI conversation kit that fits in the original
> dist. ...
> Is this what you are talking about: http://www.appliedgmc.com/
> prod.itml/icOid/775
>
> If I was going to keep and use the GMC, I would probably go that route.
> --
> 73 23' Sequoia 4 Sale
> 73 23' CanyonLands Parts Unit 4 Sale
> Upper Alabama
> "When I grow up I am going to be a curmudgeon."
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
The capacitor / condenser on the coil is for radio noise suppression. It goes on the small coil terminal connected to power (+ side). If it were
shorted it would burn up. If it is open it will not cause any problem other than poor AM radio noise filtering. For diagnosis you can leave it
installed (on the correct terminal) or remove it. It is your choice.

There is also a series resistance wire connected to the + power terminal of the coil and another wire going to the starter solenoid. I would attach
a meter to the positive coil terminal with the negative lead attached to the engine and check for voltage with the key on.

With the key on the voltage should read somewhere between 6 and 12 volts depending on whether the points are closed or open. If that voltage is there
then move the meter to the other coil terminal. The voltage there should read 0 vdc with the points closed and 12 vdc with points open.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Im willing to bet if you go in most any local auto parts store and ask for a point file or advice on setting points or God forbid, a dwell meter, youd
just hear crickets.

From what I recall in the parts business, the GM points for V8s were all pretty much the same late 50s-74, other than dual points or stiffer spring
Hi-RPM versions

Delco did make a 'Uniset' type with the points and condensor in one assembly that was easier to install.

When changing the condenser, dont remove the clamp, just loosen it enogh to slip out. Too easy to lose the screw. Ask me how I know.

Ill also jump on the pertronix bandwagon for down the road. I have also used the mallory Unilite but the pertronix is easier to install.
--
76 Glenbrook
 
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