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Nothing happens when I turn the key [message #365783] Fri, 30 July 2021 19:47 Go to next message
ktcnyc is currently offline  ktcnyc   United States
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Hello Folks - I'm on a trip In Maine and suddenly nothing happens when I turn the key on my '77. No dash lights, totally dead. It will start with the battery boost switch from the house batts and runs fine. The engine battery tests good and is getting a charge. I stopped at a Napa and changed out the battery boost solenoid but no luck there. Something just blew or disconnected somewhere but what? Any help is greatly appreciated!

Kevin Cloutier -'77 Eleganza II-455, 6 disk brakes, Edelbrock carb, headers, , resident of NYC and Dingmans Ferry, Pa. '72 MGB-GT & '73 MGB convertible Member GMCMI since 8/20
Re: Nothing happens when I turn the key [message #365784 is a reply to message #365783] Fri, 30 July 2021 19:56 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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Maybe corroded battery terminals; take them off and clean them. If not, follow the wires to the next connection(s) (hot and ground) downstream. Rinse and repeat.

Or, first maybe try connecting a jumper cable from BAT+ to the chassis side of the boost solenoid. If it starts, something in between is open.


Bill Van Vlack '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid November 2015.
Re: Nothing happens when I turn the key [message #365785 is a reply to message #365784] Fri, 30 July 2021 23:13 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I second Bill's suggestion. Check and clean BOTH ends of BOTH battery cables. Also possibly one of the cables is corroded inside under the insulation. If it starts on the house battery(s) then the problem has to be with the engine battery and its cables or connections.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
[GMCnet] Re: Nothing happens when I turn the key [message #365786 is a reply to message #365785] Fri, 30 July 2021 23:16 Go to previous messageGo to next message
Sammy Williams is currently offline  Sammy Williams   United States
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Fusible link wire between key and starter perhaps?
Loose or corroded battery terminals
Blown fuse




On Fri, Jul 30, 2021 at 23:14 Ken Burton wrote:

> I second Bill's suggestion. Check and clean BOTH ends of BOTH battery
> cables. Also possibly one of the cables is corroded inside under the
> insulation. If it starts on the house battery(s) then the problem has to
> be with the engine battery and its cables or connections.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
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Re: [GMCnet] Re: Nothing happens when I turn the key [message #365787 is a reply to message #365786] Sat, 31 July 2021 06:48 Go to previous messageGo to next message
ktcnyc is currently offline  ktcnyc   United States
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I have good voltage from the engine batt to the solenoid - cables are good and clean.

Where is this fusible link between the key and the starter?

What "fuse would be blown"?


Kevin Cloutier -'77 Eleganza II-455, 6 disk brakes, Edelbrock carb, headers, , resident of NYC and Dingmans Ferry, Pa. '72 MGB-GT & '73 MGB convertible Member GMCMI since 8/20
[GMCnet] Re: Nothing happens when I turn the key [message #365788 is a reply to message #365787] Sat, 31 July 2021 07:06 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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If the fusible link were blown, the House battery wouldn't work either.

How do you know the chassis voltage at the solenoid is "good"? A
voltmeter, used without engaging the starter can read full voltage even
though there's far too high resistance somewhere. I'm guessing the
resistance at the terminal on one of the battery cables is so high that is
dropping all the voltage when current tries to reach 200+ Amps. I had that
happen a couple of years ago -- the positive battery cable at the battery
looked great and had a clean, well-maintained connection to the battery,
but when I pulled on the cable, it slipped right out of the terminal.

Ken H.

On Sat, Jul 31, 2021 at 7:48 AM wrote:

> I have good voltage from the engine batt to the solenoid - cables are good
> and clean.
>
> Where is this fusible link between the key and the starter?
>
> What "fuse would be blown"?
> --
> Kevin Cloutier -'77 Eleganza II-455, 6 disk brakes, Edelbrock carb,
> headers, , resident of NYC and Dingmans Ferry, Pa.
> '72 MGB-GT & '73 MGB convertible
> Member GMCMI since 8/20
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Nothing happens when I turn the key [message #365790 is a reply to message #365783] Sat, 31 July 2021 08:58 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   Canada
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Kevin,

An often ignored place for poor connections is the ground path. Check that before you spend any more money. Those flat braid cables can dissolve in a corrosive environment like the east coast. Care to guess how I know??

If your diagnostic data is correct, you just have a bad connection somewhere. I hope you kept the good boost contactor that you took out.

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] Re: Nothing happens when I turn the key [message #365791 is a reply to message #365783] Sat, 31 July 2021 07:25 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
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Neutral Safety Switch?
http://www.gmcmhphotos.com/photos/g5493-gmc-cranking-improve-for-free.html


-----Original Message-----
From: kcloutier@nyc.rr.com [mailto:kcloutier@nyc.rr.com]
Sent: Friday, July 30, 2021 7:48 PM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] Nothing happens when I turn the key

Hello Folks - I'm on a trip In Maine and suddenly nothing happens when I
turn the key on my '77. No dash lights, totally dead. It will start with the
battery boost switch from the house batts and runs fine. The engine battery
tests good and is getting a charge. I stopped at a Napa and changed out
the battery boost solenoid but no luck there. Something just blew or
disconnected somewhere but what? Any help is greatly appreciated!
--
Kevin Cloutier -'77 Eleganza II-455, 6 disk brakes, Edelbrock carb, headers,
, resident of NYC and Dingmans Ferry, Pa.
'72 MGB-GT & '73 MGB convertible
Member GMCMI since 8/20
_______________________________________________
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bdub
'76 Palm Beach/Central Texas
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Re: Nothing happens when I turn the key [message #365792 is a reply to message #365783] Sat, 31 July 2021 09:34 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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You did not need to replace boost contactor as that is just a stud pass through junction on the engine positive side.
You say dash lights no go. Try the headlamps and report back. Not sure about the validity of your engine battery “test”. Digital battery load testers are USUALLY accurate but not always. You could have an intermittent cell which can be a bugger to diagnose at times.
Since BOOST works, logic says the problem is on the hot side before the boost junction. Positive battery cable to boost junction or battery itself. Could also be the Neg cable or connections on engine battery side. You don’t need to look elsewhere as Boost starts it.


John Lebetski
Woodstock, IL
77 Eleganza II
[GMCnet] Re: Nothing happens when I turn the key [message #365793 is a reply to message #365792] Sat, 31 July 2021 10:01 Go to previous messageGo to next message
Biggamehunter is currently offline  Biggamehunter   United States
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Try doing a voltage drop on the positive engine cable. B+ to starter terminal. Have some one crank it over and look at your meter. If you have more than .2 volts ,any reading on the meter, you have a bad cable or connection. Red lead on meter to battery and black lead on starter.

Sent from Mail for Windows 10

From: John R. Lebetski
Sent: Saturday, July 31, 2021 7:35 AM
To: gmclist@list.gmcnet.org
Subject: [GMCnet] Re: Nothing happens when I turn the key

You did not need to replace boost contactor as that is just a stud pass through junction on the engine positive side.
You say dash lights no go. Try the headlamps and report back. Not sure about the validity of your engine battery “test”. Digital battery load
testers are USUALLY accurate but not always. You could have an intermittent cell which can be a bugger to diagnose at times.
Since BOOST works, logic says the problem is on the hot side before the boost junction. Positive battery cable to boost junction or battery itself.
Could also be the Neg cable or connections on engine battery side. You don’t need to look elsewhere as Boost starts it.
--
John Lebetski
Woodstock, IL
77 Eleganza II
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Michael Orlandi Fairfield, Ca 1973 GMC Canyonlands Lenzi knuckles/ hubs
Re: Nothing happens when I turn the key [message #365794 is a reply to message #365792] Sat, 31 July 2021 10:33 Go to previous messageGo to next message
94nubble is currently offline  94nubble   United States
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In the last month or so I have seen people having starting problems have the starter battery cable connected to the boost side (Left) of the boost solenoid. This will have the house battery as the starting battery. The engine will start but only if the battery has a good charge. The alternator will only be charging it through the isolator. Hitting the boost will engage the engine battery to start and everything will seem normal until you try and start the engine again.


Tom McManus
1977 Royale
Chesapeake VA
[GMCnet] Re: Nothing happens when I turn the key [message #365795 is a reply to message #365794] Sat, 31 July 2021 10:58 Go to previous messageGo to next message
stu@97381.com, Emery  is currently offline  stu@97381.com, Emery   United States
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Why would they have it wired so it starts from the house battery? That doesn’t make sense to me. There are a lot of reasons it should start from the engine battery.

Emery Stora

> On Jul 31, 2021, at 9:33 AM, Tom McManus wrote:
>
> In the last month or so I have seen people having starting problems have the starter battery cable connected to the boost side (Left) of the boost
> solenoid. This will have the house battery as the starting battery. The engine will start but only if the battery has a good charge. The alternator
> will only be charging it through the isolator. Hitting the boost will engage the engine battery to start and everything will seem normal until you try
> and start the engine again.
>
> --
> Tom McManus
> 1977 Royale
>
> Chesapeake VA
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Re: [GMCnet] Re: Nothing happens when I turn the key [message #365796 is a reply to message #365787] Sat, 31 July 2021 12:42 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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As has been stated by several posters and me here, the circuits are the same when starting on the house or the engine battery. The ONLY difference between in the two scenarios is the engine battery and it's cables. So forget looking for fuses, switches, boost solenoid, etc.

You need to take voltage readings when the key is turned to the start which puts the engine battery under load. Use the same ground reference for your meter that the starter is using (the engine block).

I strongly suggest that this is a battery to engine connection problem or the battery itself. I have experienced in the past where the connections are visually clean, even wire brushed clean, but not electrically clean and still did not work. You can prove all of this by using your meter and referencing all of your readings to engine block ground. Then only take readings while the key is turned and held in the start position.

All of the above assumes that the coach is wired in the OEM configuration with no modifications to engine and house battery electrical systems.

Do not throw any parts at this until you have proven with your meter what the problem is.

Ken B.

ktcnyc wrote on Sat, 31 July 2021 06:48
I have good voltage from the engine batt to the solenoid - cables are good and clean.

Where is this fusible link between the key and the starter?

What "fuse would be blown"?


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Re: Nothing happens when I turn the key [message #365797 is a reply to message #365793] Sat, 31 July 2021 12:55 Go to previous messageGo to next message
ktcnyc is currently offline  ktcnyc   United States
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John- You were so right in the basic logic -
"Since BOOST works, logic says the problem is on the hot side before the boost junction. Positive battery cable to boost junction or battery itself.
Could also be the Neg cable or connections on engine battery side. You don’t need to look elsewhere as Boost starts it. "

It was a very funky, dirty connection to the ground battery terminal connector.
Moby (my coach) fired right up!

Many many thanks and to all that chimed in

KC


Kevin Cloutier -'77 Eleganza II-455, 6 disk brakes, Edelbrock carb, headers, , resident of NYC and Dingmans Ferry, Pa. '72 MGB-GT & '73 MGB convertible Member GMCMI since 8/20
Re: [GMCnet] Re: Nothing happens when I turn the key [message #365799 is a reply to message #365797] Sat, 31 July 2021 15:10 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Great. You got it and hopefully are on your way.

Ken B.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Re: Nothing happens when I turn the key [message #365801 is a reply to message #365795] Sat, 31 July 2021 18:14 Go to previous message
94nubble is currently offline  94nubble   United States
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[quote title=stu@97381.com, Emery wrote on Sat, 31 July 2021 11:58]Why would they have it wired so it starts from the house battery? That doesn’t make sense to me. There are a lot of reasons it should start from the engine battery.

Emery Stora

Because it works and when something works, life go on until it doesn't. I had a guy that thought that the boost solenoid was the starter solenoid. He had owned too many FORDS. I have told more than one owner to back away from the vehicle and call a professional.


Tom McManus
1977 Royale
Chesapeake VA
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