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| | | | Joined: Apr 2009 Posts: 187 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 187 | I heard somewhere that when switching from 6 volt to a 12 volt system you may have a problem with the 12v starter pinion gear not meshing with the flywheel ring gear properly, has anyone heard this before.
I would rather be late 10 minutes in this life than 10 minutes early for the next
The reason my lady and I have been together so long is because of the kids. Neither one of us wanted sole custody
| | | | | Joined: May 2016 Posts: 268 'Bolter | | 'Bolter Joined: May 2016 Posts: 268 | Yes a 6volt starter must go with a proper 6 volt flywheel with the corresponding tooth count.
1949 gmc 1-ton | | | | | Joined: May 2016 Posts: 268 'Bolter | | 'Bolter Joined: May 2016 Posts: 268 | I may be wrong but I believe 6volt needs 139 tooth and 12 volt is something like 168? Someone will correct me
Last edited by Johnny N; 10/17/2021 5:30 PM.
1949 gmc 1-ton | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy Blanch53, unfortunately the 6 volt and 12 volt starter armature shafts are different diameters, so a simple swap of starter drives is not possible. The six volt starter will survive quite well on twelve volts, providing it is in good condition and that is not used to crank the engine for excessive amounts of time. Good luck with it. | | | | | Joined: Apr 2009 Posts: 187 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 187 | thanks for the replies and information, I have a 6v system with the 235. I have aquired a 12v starter and generator and want to make sure if I do convert that it is done correctly
I would rather be late 10 minutes in this life than 10 minutes early for the next
The reason my lady and I have been together so long is because of the kids. Neither one of us wanted sole custody
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Like 3B said, if you want to use the 12v starter, need to change to 12v flywheel. 6v starters work fine on 12v, just don’t sit on the starter, no need to change flywheel.
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: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | Everyone has provided good/correct information on the switch over. One thing not mentioned is the faster spin of the 6 volt starter running on 12 volts. If you have a cantankerous starting Engine the faster spin can be a blessing. Another advantage is you don’t have to pull the transmission and clutch and change out the flywheel. Install your 12 volt generator and call it good. Stovebolt has a very helpful Tech Tip on 12 volt conversion. Search the Tech Tips at the top of the page.
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
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| | | | | Joined: Jan 2016 Posts: 1,101 'Bolter | | 'Bolter Joined: Jan 2016 Posts: 1,101 | There is a local shop in my area that does Alternator, generator, starter and water pump rebuilds for shops all over the U.S. Last time I talked to the guy he stated they send out about 40 rebuilt alternators a week. they have been in business for years and really know their stuff. I don't know if it is possible but if you want to go this directions I can send you their contact information and they could possibly rebuild and convert your 6v starter to a 12v starter using the existing pinion gear, avoiding a needed change of the fly wheel. | | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | blanch 53 When you switch to 12 volt,electrically,it will make your starter whip over much better. switching mechanically is when parts can clash. | | |
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