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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Today I hooked up starter alternator coil to new speedway 20 circuit harness Hooked up ignition wires to the stock switch 1952 Chevy truck basically it's a on off switch I'm able to start the truck but have to disconnect the battery to turn it off should I replace the ignition switch with a new universal one truck has stomp start Stock switch has no markings on the 3 post on the back of switch. Thanks Robert
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| | | | | Joined: Jul 2014 Posts: 1,289 Moderator for Tons o' Fun , Co-Moderator Driveline Forum | | Moderator for Tons o' Fun , Co-Moderator Driveline Forum Joined: Jul 2014 Posts: 1,289 | Sounds like you might have the wire going from the ignition switch to the coil "hot" all the time. Check the ignition switch with a volt meter to see if that is happening. The old wiring diagram had a two pink wires on one terminal with one going to the gas gage and the other going to the + side of the coil.
Ron - - Dusty53 1954 Chevy 3604In the Gallery Forum "You can't dance with the Devil and then wonder why you're still in Hell." "They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel." | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Thanks dusty I will check coil wires asap
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | You need to, as said, check to see what the switch does. Use a continuity meter to see which terminals are connected to which other terminal when switch is operated. Then you will attach a battery hot wire to one terminal and the switch will turn on (energize) one or more of the other terminals. The schematic for stock truck and as Dusty says: hot wire from Voltage Regulator "Bat" terminal to ign sw hot terminal. One of the other terminals (the one that gets turned on/off by the hot terminal) goes to gas gauge and to coil. Your testing of switch will tell you what terminal on Ign Sw should be used for hot. Only two terminal were used. If you have a 3 terminal switch, one will be unused. No accessories to turn on, back in the day. Study the original 52 wiring diagram and the kit wiring diagram and meld them to suit. These two diagrams may or may not match wire colors. So wire per function. Exact color is not necessary but nice if possible.
How many positions does your key have? 2 position-Center and right on? or 3 position-center and left and right?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | 2 left off right on digging out the manual for the 52 now Thanks for help
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| | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | The truck was 12 volt when I got it so no voltage regulator had 12 volt converted generator I took that off now has alternator
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| | | | | Joined: Jul 2000 Posts: 2,188 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,188 | You said you have an alternator, so no voltage regulator anymore? You wouldn't be the first guy to have a engine that won't shut off due to an improperly wired alternator. Easy to check - disconnect the alternator and try again.
Gord 🇨🇦 ---- 1954 1/2 ton 235 4 speed | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Yes, as Gord says, may need a diode or idiot light. I have a link to a kit for that. $10.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Jul 2014 Posts: 1,289 Moderator for Tons o' Fun , Co-Moderator Driveline Forum | | Moderator for Tons o' Fun , Co-Moderator Driveline Forum Joined: Jul 2014 Posts: 1,289 | Oh heck, I plumb forgot about the alternator conversion issue! Bartamos and Gord&Fran are right on. That diode prevents feed back to the coil . Disconnect the plug from the alternator and start your truck. Then turn the ignition to "off" .......if it "shuts off" you've found your problem. I think.
There's another post in this forum by 1954Chevy 5Window who had the same issue, you might check that out as it describes a similar problem, the alternator and diode issue.
Last edited by Dusty53; 10/22/2017 3:00 PM.
Ron - - Dusty53 1954 Chevy 3604In the Gallery Forum "You can't dance with the Devil and then wonder why you're still in Hell." "They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel." | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Thanks to all in attempt to solve this issue Today went through starter coil alt ignition wires and still the same even disconnected alt wires truck still running had to disconnect battery to turn off switch still not working Again thanks for help
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | If there is only one wire on coil positive and it's from the switch and you disconnected alternator, then it is the switch. Either bad or miswired. That probably means the truck will start when key is off.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Miswire sound about right next chance I will disconnect and start over one by one I really appreciate the input on this Robert
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| | | | | Joined: Nov 2001 Posts: 1,517 'Bolter | | 'Bolter Joined: Nov 2001 Posts: 1,517 | Latroca, I sent you a PM. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | It's always nice when someone let's us know what the fix was when they solve it. Please let us know. Thanks.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Feb 2004 Posts: 80 Shop Shark | | Shop Shark Joined: Feb 2004 Posts: 80 | Yes, as Gord says, may need a diode or idiot light. I have a link to a kit for that. $10. Bartamos - I might have missed it but I did not see your link to the "kit" you referred to earlier in the conversation. I am a few weeks away from rewiring my 50 3100 with a new harness and new alternator and would like to avoid any problems! Thanks in advance. | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Hello Bruce, I did not post it because wasn't sure if he had that problem. Turns out he does not. This Ebay kit just plugs in. You can also DIY with a diode or 12V bulb. Search here and the internet for info and part number. Diodes block current in one direction and are polarized. I had this problem and installed a 12V bulb which solved it. In that case the resistance of the filament was sufficient.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Ignition switch update had a few minutes to change things around I disconnect positive wire from coil to starter put + coil wire to ignition switch started truck turned it off with switch than had to shut it down to charge low battery fresh start tomorrow with full battery Step in right direction Thanks to all with solutions
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Ignition switch update had a few minutes to change things around I disconnect positive wire from coil to starter put + coil wire to ignition switch started truck turned it off with switch than had to shut it down to charge low battery fresh start tomorrow with full battery Step in right direction Thanks to all with solutions Sounds like you had a wire from the starter hot post to the coil. We did not know that. That is your problem. As Dusty53 said, You had an unswitched hot wire to coil As I said........ If there is only one wire on coil positive and it's from the switch and you disconnected alternator, then it is the switch. Either bad or miswired. That probably means the truck will start when key is off. Sounds like you are in business. Another success story. Well done.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Ok just a thought been a few threads about stock heater switches When I wire up electric cooling fan I had planned on a toggle switch to use when ever I wanted to turn on fan .so here's the question I have a 2 speed fan switch original fan switch for the truck if I were to add a voltage reducer would this switch work for the electric cooling fan. Thanks Robert
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | I guess you have a 12V electric radiator cooling fan installed and you want to use a two speed 6V heater fan motor switch. I guess you don't have a thermostat controlling the 12V cooling fan. So if this is all true, we can discuss. If not, re explain.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Correct no thermostat control would like to switch fan on and off manually as needed And have this switch that's pretty cool and would like to see if I could use it instead of using it for garage art.
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Assuming you are talking about a 12V aftermarket or donor electric radiator cooling fan, that switch is NOT suitable for an electric fan.
Red leader to Blue leader....Negatory on the switchatory.
Using a dash on/off switch is the wrong way to go. Using a two speed switch will be a disaster for the fan motor if low speed is used. The voltage reducers you have been reading about are to reduce 12V to 6V to operate existing 6V components. I have asked you this already in a previous post but you did not confirm. A radiator cooling fan? NOT a cab, blow in your face, cooling fan, right? A 12V fan, right?
The proper way is a thermostatically controlled electronic fan control switch, operating the fan thru a relay. Also, what is the reason for an electric fan? What motor do you have? 235? Is it overheating? There is a fix that moves the fan up for some motors, available from Pre68Dave. AD motors should not need an E-Fan if all is well. If A/C is added, maybe.
I believe this discussion should be on a new thread. It's kind of a general rule not to morph.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Yes Bart I was talking about a radiator electric fan Was just a thought about using original fan switch if possible I do plan on a relay for radiator fan .due to California traffic requires lots of sitting still was thinking wouldn’t hurt to put a fan on to keep engine cool.and just turn on as need or when not moving Thank you for input and wealth of information Robert
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| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | It may be possible to use the switch only on Hi. Using the Lo would supply less than 12V to motor and may or may not be OK. The 6V heater switch should be built for higher 6V amps, therefore OK for 12V if using a relay. Fuse the circuit very near the amps of the fan. As you know, the relay has big contacts to handle the startup load of the fan motor and the 6V switch would just turn on the relay. My comment was about not using a switch and rely on user to self control the heat. Your lag time would be a problem, you would watch an old temp gauge to determine when to engage. Using a cab switch is not the normal way to go. It your case, in would be OK, you don't already have an overheat to solve. You are just installing a safety.
It may save a lot of effort to wait and see if it overheats. I now understand what you want to do and with what parts. I'm slow. Thanks Robert.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn | | | | | Joined: Mar 2010 Posts: 10,272 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,272 | Most cooling fan relays are switched on by less than 1 amp. Your heater switch on high would work just fine for energizing your relay. Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Mar 2010 Posts: 295 'Bolter | | 'Bolter Joined: Mar 2010 Posts: 295 | Thanks Bart and carl thanks for input on this and yes just for safety and prevent a possible over heat have not had that problem in the past but seen many many six cylinder cars and trucks over heat sitting in traffic was also thinking for driveway idle time getting the truck back on the road Robert
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| | | | | Joined: Oct 2017 Posts: 42 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2017 Posts: 42 | Yes, as Gord says, may need a diode or idiot light. I have a link to a kit for that. $10. I would be interested in hearing more about this kit. I understand I will need to add a GEN light to make the new alt work.
Vintage Paul Paul O'Neil, SoCal 1951 Chevy 3600 Project
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