Labor Day Putting down your wrenches or time for MORE wrenching? 
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | On my 55.2 GMC, I have pulled gently on the switch while pushing on the spring loaded button on the port side of the switch. All positions of switch button(all the way in, first notch, all the way out) have been tried, no joy. Am I missing something, or is it likely clogged with dirt( both devices move easily) or something else?
Th@nks,
Edi
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2019 Posts: 4,472 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,472 | Try twisting it one direction or the other as this worked for me.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Phil,
Thanks, I have been trying that, I will keep at it.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Dec 2013 Posts: 224 'Bolter | | 'Bolter Joined: Dec 2013 Posts: 224 | I’d keep working on the button while pulling and turning on the knob. The button likely is rusted etc and is not releasing. Perhaps if there’s an opening some light oil may help. Don’t pull too hard or you may break the tang holding the switch on. I know by experience! | | | | | Joined: Mar 2014 Posts: 4,475 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,475 | Ed, sometimes the bakelite slider inside will break (usually partially but recently I ran across one that broke completely) and that will make things pretty horsey. One, the switch won't work well any longer. Two, you can't get the knob out occasionally. If you go back several posts, you'll see a tutorial I made showing how to disassemble these and repair/rebuilt them. I was hoping that might become a sticky or a tech note, but guess not. Once you do that, they usually work just like new. Good luck.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Jon,
Thanks, I have been working mine gently every time I go outside, turning the knob every time, no joy. I will look up your post.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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