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Ignition / starting issues [message #263132] Wed, 01 October 2014 21:54 Go to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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Hello everybody,

All has been great lately and we were about to go on our last trip for the year before putting the coach away for the winter. Went to move the coach and to our surprise, it will not start. Turns over fine, but no fire, but is getting plenty of gas as the carb is soaked with gas. I let it sit for a while, and shot some starter fluid in just to see, and again no fire. So I started at the top of the list checking the ignition components: Checked the cap and rotor (which were recently replaced with new) and they look fine. Replaced the coil with a spare, no luck. Replaced the ignition module, no luck. So now I'm back to square one and give up for now. I have not removed a plug yet to check for spark, but that's next for tomorrow. What other tests can I do to check the ignition system? I'm up for any suggestions as I'm completely stumped. We just had the coach out last weekend and it was doing fine.

Thanks as always....

Mickey


Mickey 1977 Kingsley, 403, Lansing, MI
Re: Ignition / starting issues [message #263133 is a reply to message #263132] Wed, 01 October 2014 22:05 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   United States
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Check for 12 volts on the single wire going into the distributor cap. There should be 12 volts there with the ignition ON and while cranking (OK there will be a bit less less than 12 volts while cranking).

If that is there, check that the distributor housing is at ground potential (zero volts). The dissimilar metals between the aluminum dist. housing and the block can cause corrosion leaving the distributor housing ungrounded.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Ignition / starting issues [message #263134 is a reply to message #263132] Wed, 01 October 2014 22:10 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   United States
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Also check to be sure the 12 volt wire going into the cap is up all the way into the connector. The brass contact has been known to come loose from its housing and fall downward, losing connection. Happened to me!



Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Ignition / starting issues [message #263144 is a reply to message #263132] Thu, 02 October 2014 06:56 Go to previous messageGo to next message
77Royale   United States
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Sent you a pm.

77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: Ignition / starting issues [message #263188 is a reply to message #263144] Thu, 02 October 2014 18:19 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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OK I have done some additional tests, and confirmed ignition IS OK. There is 12V going in to the distributor with the ignition key on. I also hooked up a timing light and it's showing a spark through the wires. So based on that I started looking more at the carb. I've found that it seems to be severely flooded as I could see gas pooled under the carb in the intake area. I pumped out everything and am letting it sit in hopes it will dry out. The question is, I have no idea how that much gas got down there. I cranked it without pumping the primer jets and it almost looks like gas is pooling up again. I'm still looking this over but open to any suggestions... thanks again.

Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Ignition / starting issues [message #263189 is a reply to message #263188] Thu, 02 October 2014 18:28 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Sunk Float. Had a bunch of trouble with 3 different floats on a 500
Cadillac in a GMC this summer on the route 66 rolling rally. Final cure was
a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made
off shore.
Jim Hupy
Salem,OR
78 GMC ROYALE 403
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Re: [GMCnet] Ignition / starting issues [message #263193 is a reply to message #263189] Thu, 02 October 2014 18:58 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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James Hupy wrote on Thu, 02 October 2014 18:28
Sunk Float. Had a bunch of trouble with 3 different floats on a 500
Cadillac in a GMC this summer on the route 66 rolling rally. Final cure was
a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made
off shore.
Jim Hupy
Salem,OR
78 GMC ROYALE 403
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Yikes. But makes sense, I didn't think of that. I'll have to investigate that further. What surprises me is that I can't get this thing to fire at all. I sucked out as much gas as I could and then sprayed a couple shots of starter fluid down there and turned it over without priming it, but got nothing. But I guess if it's pushing that much gas through then that might be why. I really hope the cylinders are OK, I'm assuming it would take quite a bit for that to be an issue. I sucked out probably 2-3 ounces of gas.

Are you suggesting I get a phenolic float for this carb, if one is available? Thanks Jim.


Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Ignition / starting issues [message #263195 is a reply to message #263188] Thu, 02 October 2014 18:54 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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CHECK YOUR OIL IMMEDIATELY TO SEE IF IT SMELLS LIKE GASOLINE!

Yes, I am shouting a warning!

If it does, you should change the oil immediately and eliminate that gasoline leak (likely a stuck float needle) before running the engine!

A gas-oil mixture in the crankcase does nasty things to bearings in the engine! That stuff doesn't lubricate your engine worth a damn!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
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> Date: Thu, 2 Oct 2014 17:19:39 -0600
> To: gmclist@temp.gmcnet.org
> From: mickey@apex-internet.com
> Subject: Re: [GMCnet] Ignition / starting issues
>
> OK I have done some additional tests, and confirmed ignition IS OK. There is 12V going in to the distributor with the ignition key on. I also hooked
> up a timing light and it's showing a spark through the wires. So based on that I started looking more at the carb. I've found that it seems to be
> severely flooded as I could see gas pooled under the carb in the intake area. I pumped out everything and am letting it sit in hopes it will dry out.
> The question is, I have no idea how that much gas got down there. I cranked it without pumping the primer jets and it almost looks like gas is
> pooling up again. I'm still looking this over but open to any suggestions... thanks again.
> --
> Mickey
> 1977 Kingsley, 403, Lansing, MI

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Re: [GMCnet] Ignition / starting issues [message #263196 is a reply to message #263189] Thu, 02 October 2014 19:02 Go to previous messageGo to next message
Otterwan   United States
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James Hupy wrote on Thu, 02 October 2014 16:28
Sunk Float. Had a bunch of trouble with 3 different floats on a 500
Cadillac in a GMC this summer on the route 66 rolling rally. Final cure was
a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made
off shore.
Jim Hupy
Salem,OR
78 GMC ROYALE 403
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How can ethanol "wreak havoc" on a brass float? Brass floats have been recommended for QJets for years.


1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
Re: [GMCnet] Ignition / starting issues [message #263202 is a reply to message #263195] Thu, 02 October 2014 19:40 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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k2gkk wrote on Thu, 02 October 2014 18:54
CHECK YOUR OIL IMMEDIATELY TO SEE IF IT SMELLS LIKE GASOLINE!

Yes, I am shouting a warning!

If it does, you should change the oil immediately and eliminate that gasoline leak (likely a stuck float needle) before running the engine!

A gas-oil mixture in the crankcase does nasty things to bearings in the engine! That stuff doesn't lubricate your engine worth a damn!



Roger that, once the carb issue is addressed, we'll change the oil on the spot... I'm not even taking any chances at this point.


Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Ignition / starting issues [message #263204 is a reply to message #263196] Thu, 02 October 2014 19:49 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Because ethanol can be corrosive to brass, zinc, aluminum and other metals. You should see what it does to lawn mower carbs.

Emery Stora

> On Oct 2, 2014, at 7:02 PM, David Orders wrote:
>
> James Hupy wrote on Thu, 02 October 2014 16:28
>> Sunk Float. Had a bunch of trouble with 3 different floats on a 500
>> Cadillac in a GMC this summer on the route 66 rolling rally. Final cure was
>> a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made
>> off shore.
>> Jim Hupy
>> Salem,OR
>> 78 GMC ROYALE 403
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> How can ethanol "wreak havoc" on a brass float? Brass floats have been recommended for QJets for years.
>
> --
> 1976 Royale "Twinkie II" Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to
> us."
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Re: [GMCnet] Ignition / starting issues [message #263221 is a reply to message #263196] Thu, 02 October 2014 21:23 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Otterwan wrote on Thu, 02 October 2014 20:02
James Hupy wrote on Thu, 02 October 2014 16:28
Sunk Float. Had a bunch of trouble with 3 different floats on a 500 Cadillac in a GMC this summer on the route 66 rolling rally. Final cure was a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made off shore.
Jim Hupy

How can ethanol "wreak havoc" on a brass float? Brass floats have been recommended for QJets for years.

Yes David,

But China mandated the elimination of lead based solder. So, the stuff they are using is - I am told - a tin, zinc and copper alloy. It is very susceptible to attack from things like alcohol. I don't understand all the chemistry of why.

Matt - Hold up at the Cabela's in Hoffman Estates for the night.


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
Re: [GMCnet] Ignition / starting issues [message #263300 is a reply to message #263196] Fri, 03 October 2014 19:10 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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David, only know what I learned on the road. I soldered up 6 cracks in one
brass float that was in a " after market rebuilt" carb installed by Camping
World. It sank again in a couple of days. Bought a brand new brass float
from O'rielies. It cracked and sank in 4 days and required a 250 mile tow.
Yes, I am recommending that a phenolic float be used to replace Chinese
Junk brass floats.
Jim Hupy
On Oct 2, 2014 5:03 PM, "David Orders" wrote:

> James Hupy wrote on Thu, 02 October 2014 16:28
>> Sunk Float. Had a bunch of trouble with 3 different floats on a 500
>> Cadillac in a GMC this summer on the route 66 rolling rally. Final cure
> was
>> a phenolic float. Ethanol fuel wreaks havoc on the new brass floats made
>> off shore.
>> Jim Hupy
>> Salem,OR
>> 78 GMC ROYALE 403
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> How can ethanol "wreak havoc" on a brass float? Brass floats have been
> recommended for QJets for years.
>
> --
> 1976 Royale "Twinkie II" Lynnwood WA - "We may not be able to stop all
> evil in the world, but I know that how we treat one another is entirely up
> to
> us."
> _______________________________________________
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Re: [GMCnet] Ignition / starting issues [message #263301 is a reply to message #263189] Fri, 03 October 2014 19:37 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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We had the opposite problem with aviation carbs. They released an Airworthiness Directive stating that we had to switch to composite (what ever that is) floats. A couple of years later we got another AD stating that we had to remove the composite floats and go back to brass ones again. I've only had one with a hole in it. It was on a generator. A little solder on the crack took care of the problem.

Who knows what is best at this point.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Ignition / starting issues [message #263306 is a reply to message #263301] Fri, 03 October 2014 20:09 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Ken when this stuff was made from all new raw materials, and quality was
controlled according to S.A.E standards, brass floats were superior. But
this ain't those times. Sad, but when DELPHI went away, so did a lot of
other stuff.
Jim Hupy
On Oct 3, 2014 5:37 PM, "Ken Burton" wrote:

> We had the opposite problem with aviation carbs. They released an
> Airworthiness Directive stating that we had to switch to composite (what
> ever that
> is) floats. A couple of years later we got another AD stating that we had
> to remove the composite floats and go back to brass ones again. I've only
> had one with a hole in it. It was on a generator. A little solder on the
> crack took care of the problem.
>
> Who knows what is best at this point.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
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Re: [GMCnet] Ignition / starting issues [message #263337 is a reply to message #263306] Sat, 04 October 2014 12:40 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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OK I'm in to the carb where the float is. However I'm stuck at the point where I remove the assembly that is just above the float itself. Including a pic below of what I'm talking about. How do I remove this in order to get down in to where the float is?

http://www.gmcmhphotos.com/photos/carburetor-repair/p56117-float-area.html

Thanks again.


Mickey 1977 Kingsley, 403, Lansing, MI

[Updated on: Sat, 04 October 2014 13:00]

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Re: [GMCnet] Ignition / starting issues [message #263338 is a reply to message #263337] Sat, 04 October 2014 12:59 Go to previous messageGo to next message
Otterwan   United States
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mickey szilagyi wrote on Sat, 04 October 2014 10:40
OK I'm in to the carb where the float is. However I'm stuck at the point where I remove the assembly that is just above the float itself. Including a pic below of what I'm talking about. How do I remove this in order to get down in to where the float is?

http://www.gmcmhphotos.com/photos/carburetor-repair/p56117-float-area.html

I noticed the float is already a phenol one, so I'm guessing this or the needle is the issue here. I'll just replace both since I'm in there.

Thanks again.


That black thing is just a "stuffer block" and should lift out easily.


1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
Re: [GMCnet] Ignition / starting issues [message #263339 is a reply to message #263338] Sat, 04 October 2014 13:03 Go to previous messageGo to next message
mickey szilagyi is currently offline  mickey szilagyi   United States
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Otterwan wrote on Sat, 04 October 2014 12:59


That black thing is just a "stuffer block" and should lift out easily.


That's what I thought too, but the assembly just above that stuffer block has to come out first somehow, and that's where I'm stuck at the moment. Thanks!


Mickey 1977 Kingsley, 403, Lansing, MI
Re: [GMCnet] Ignition / starting issues [message #263341 is a reply to message #263339] Sat, 04 October 2014 13:22 Go to previous messageGo to next message
Otterwan   United States
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mickey szilagyi wrote on Sat, 04 October 2014 11:03
Otterwan wrote on Sat, 04 October 2014 12:59


That black thing is just a "stuffer block" and should lift out easily.


That's what I thought too, but the assembly just above that stuffer block has to come out first somehow, and that's where I'm stuck at the moment. Thanks!


That's the power piston and metering rods. They just lift out too. If they don't, try gently pressing them down then remove your finger and let them bounce up. They should pop out.

http://image.highperformancepontiac.com/f/tech/27299368+w799+h499+cr1+ar0/hppp_0311_23_z%2Brochester_quadrajet_carburetor%2Bmetering_rods.jpg

http://image.highperformancepontiac.com/f/tech/27299368+w799+h499+cr1+ar0/hppp_0311_23_z%2Brochester_quadrajet_carburetor%2Bmetering_rods.jpg



1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
Re: [GMCnet] Ignition / starting issues [message #263342 is a reply to message #263341] Sat, 04 October 2014 13:29 Go to previous messageGo to previous message
Otterwan   United States
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It just dawned on me that if your power piston is stuck, that could be your whole problem. If stuck it can act like the secondaries were open all the time, even thought the air valve is closed. Thus flooding and popping.

"Jammed Power Piston:
Results in: Poor idle, rich idle, ineffective idle mixture screws, hesitations and stumbles.
Comments: The power piston can be jammed in either the full lean or full rich position, producing the same symptoms as an incorrect spring. You can test the power piston with the engine "off" by inserting a thin, long screwdriver down the bowl vent in the air horn. You should be able to depress the power piston and feel it pop back up. A jammed piston is usually caused by dirt entering the bowl, but can also be caused by carbon sooting up through the intake manifold from bad valves or valve timing problems."


1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
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