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[GMCnet] Starter Problem [message #280013] Tue, 16 June 2015 09:42 Go to next message
glwgmc is currently offline  glwgmc   United States
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Registered: June 2004
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Senior Member
Rebuilt starters acquired from chain auto stores seem to have solenoid issues far more often than they should. When you take yours out, remove the solenoid contactor and see if it looks like thin beer can metal with a little copper sputtered on. If so, it will likely randomly fail to pass enough current to spin the starter. On our Royale three of the four we have tried were that way and the failure always occurred in the most inconvenient place with a hot engine. Let it cool for an hour or two and it would start normally. Some say heat it the issue and suggest heat shields. That may help, but I think the root cause is these cheesy contactors. Jim Hupy has a rebuilder in Salem, OR that appears to use real copper contactors that are supposed to cure this issue. I sure hope so as we have this rebuilders starters in both our coaches now. The east and west coast Jims may also have good starter sources. No more chain store wonder rebuilds for me.

Also, be sure your battery-to-starter cable is at least 2 ga wire (0 or larger is better), not the 4 ga stuff you can buy off the shelf. Our starters can pull as much as 600 amps and a 4 ga wire will simply not support that. It is best to follow Gene Fisher’s suggestion to run a 2 ga or larger wire directly from the battery + to the starter and another from the battery - directly to the engine block. Far too often the frame to engine ground is insufficient to carry the starting current required. While you are at it, have a 2 ga or larger wire made to run from the battery + to the chassis side of the boost solenoid in case you have to use that. A 4 ga wire size is fine to run from the chassis side of the boost solenoid to the coach + to power the lights and other coach related circuits.

BTW, the starter is easy to remove and replace once you get the coach up on sturdy jack stands enough to be able to climb under there. Be sure to pull the negative cable off of the starting battery before you do anything else. Also, if you have a battery combiner disconnect that before you attempt top remove the starter cable as well. You don’t want sparks flying around in your face when you are upside down under there!

Jerry
Jerry & Sharon Work
Kerby, OR
glwork@mac.com
http://jerrywork.com

78 Royale 455
77/94 Clasco 455
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Message: 9
Date: Tue, 16 Jun 2015 07:38:13 -0400
From: Gary Mills
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Starter Problem
Message-ID:
Content-Type: text/plain; charset=utf-8; format=flowed

I think I have a problem with my starter. When I turn the key I only get
a click, as if the battery is low. This happens hot or cold and not
every time. Most times I can hit the boost switch and it will turn over.
But not always. When this does not work I lift the hatch and tap on the
starter with the handle of a hammer or screw driver. This seems to work
every time. But it is a real pain when the engine is hot. The starter is
not that old. It was a rebuild when I bought it. Could it be the
solenoid? Most all the wires are new and all are tight. Good ground to
the block of the engine. Is there something I could do, short of
removing it? That sucker is heavy. I think that was a stupid question.
I am sure it has to come out. Maybe have it rebuilt?

--
Gary W. Mills
Livonia, MI
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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] Starter Problem [message #280046 is a reply to message #280013] Tue, 16 June 2015 17:40 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
Messages: 458
Registered: September 2013
Location: Odessa FL
Karma: 7
Senior Member
My coach had similar issues. Drove the PO nuts despite replacing the starter and solenoid several times. I got a screaming deal on it because of that.

I did what I have done on other cars and went to a remote ford type solenoid and uses a copper jumper to bypass the contacts. Also used huge welding cable. Not one issue since, even hot with a marginal battery


76 Glenbrook
Re: [GMCnet] Starter Problem [message #280059 is a reply to message #280013] Tue, 16 June 2015 20:59 Go to previous messageGo to next message
George B. is currently offline  George B.   United States
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Registered: February 2012
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Senior Member
I too had starter problems. Every time I stopped for gas I was worried if that starter would turn enough to start up and I would be blocking traffic and cussed at. I followed Gene Fisher's advice http://www.gmcmhphotos.com/photos/g5493-gmc-cranking-improve-for-free.html and had new battery cables made up at a local battery shop. They were able to make me double cables with a single connector at the battery with 0 ga welding cable to run (+) direct to the starter and I think a 4 ga cable to the boost solenoid. Same thing for the ground cable (-) direct to engine block and the other cable to the chassis ground. I also got a new (rebuilt) premium life-time warranty starter from NAPA and while at it a new battery. Now that starter seems powerful enough to drive the coach on. Worth the effort - Thanks Gene! Best not to leave any old weak links in that starter circuit. (Another good investment for positive marriage relations)

Also related, there are two or more flat ground straps that bond the frame to the body in the front and rear at the main supports (wish I knew what to call them). Some of mine were broken/corroded/not attached. Good idea to check these and replace if necessary. So many electrical issues in these coaches have a ground problem as a root cause.


George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
Re: [GMCnet] Starter Problem [message #280116 is a reply to message #280059] Wed, 17 June 2015 13:06 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Registered: July 2007
Location: SE Wisc. (Palmyra)
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Senior Member
George B. wrote on Tue, 16 June 2015 20:59


Also related, there are two or more flat ground straps that bond the frame to the body in the front and rear at the main supports (wish I knew what to call them). Some of mine were broken/corroded/not attached. Good idea to check these and replace if necessary. So many electrical issues in these coaches have a ground problem as a root cause.


See here for some pics of the OEM frame grounds.

http://www.gmcmhphotos.com/photos/g6081-frame-ground-connections-2c-1974.html

Note the construction from fine wires. After 40 years these are probably almost gone on your coach.

The trans to frame ground is a bugger to get off. Don't bother. Run a ground cable from the engine ground bolt to the frame by the RH front body mount.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Starter Problem [message #280118 is a reply to message #280116] Wed, 17 June 2015 13:18 Go to previous message
George B. is currently offline  George B.   United States
Messages: 213
Registered: February 2012
Karma: 1
Senior Member
midlf wrote on Wed, 17 June 2015 11:06
George B. wrote on Tue, 16 June 2015 20:59


Also related, there are two or more flat ground straps that bond the frame to the body in the front and rear at the main supports (wish I knew what to call them). Some of mine were broken/corroded/not attached. Good idea to check these and replace if necessary. So many electrical issues in these coaches have a ground problem as a root cause.


See here for some pics of the OEM frame grounds.

http://www.gmcmhphotos.com/photos/g6081-frame-ground-connections-2c-1974.html

Note the construction from fine wires. After 40 years these are probably almost gone on your coach.

The trans to frame ground is a bugger to get off. Don't bother. Run a ground cable from the engine ground bolt to the frame by the RH front body mount.


Good pictures, thanks. Even if some of these ground straps are intact the actual connection could be rusted and corroded enough to limit the electrical path. Clean these connections and install star washers and some problems may go away.


George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
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