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| | | | Joined: Sep 2014 Posts: 120 'Bolter | | 'Bolter Joined: Sep 2014 Posts: 120 | My new to me '51 Chev panel came with a GMC hot water heater. The front is marked "Special GMC Heater." It has a separate squirrel cage motor for the defroster. The squirrel cage and regular fan motors both work. They appear to run well on 12 V.
Of the 3 outlet doors, only one has knobs on it. The knobs are similar to the knobs that are on the ash tray door of the '51. Looks like there should be two of these rectangular knobs per door.
So my question is, where can I find matching knobs for the heater?
1 1951 Chev Panel with a 350 small block, automatic tranny.
1 2004 Chev 2500 HD pickup... stock
1 1950 Chev 5 window pickup; 261 c.i. engine, 4 on the floor.
With lots of time and money, any Stovebolt can be restored.
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | My stupid answer is "Where they stock hen's teeth." Your best bet is a place a Part Wanted ad in the Swap Meet and hope someone has one collecting dust in their shop/garage. Provide a link to good photo of your heater. Is it in the lower left of this image (compliments of Rob English's website)? http://www.oldgmctrucks.com/img01183.gif | | | | | Joined: Sep 2014 Posts: 120 'Bolter | | 'Bolter Joined: Sep 2014 Posts: 120 | Tim: I found some hen's teeth.  . The two remaining knobs on my heater door are exactly like the knob on the ashtray. Classic Parts has them for $7.49 ea. Shame on me for not looking more closely and comparing the two knobs before I submitted my post. Jerry
1 1951 Chev Panel with a 350 small block, automatic tranny.
1 2004 Chev 2500 HD pickup... stock
1 1950 Chev 5 window pickup; 261 c.i. engine, 4 on the floor.
With lots of time and money, any Stovebolt can be restored.
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Excellent, Jerry
Thanks for reporting back here. | | | | | Joined: Sep 2014 Posts: 120 'Bolter | | 'Bolter Joined: Sep 2014 Posts: 120 | Thanks Tim. I light bulb finally when on this morning. LOL
As mentioned in the original post, I've run both fan motors on 12V,
and they hum along just fine.
But, is there a way to tell if the motors are 6V or 12V. There are
no voltage markings on the motors and they "look" original.
Maybe I should refer this question to the "electrical" section of this forum?'
Jerry
1 1951 Chev Panel with a 350 small block, automatic tranny.
1 2004 Chev 2500 HD pickup... stock
1 1950 Chev 5 window pickup; 261 c.i. engine, 4 on the floor.
With lots of time and money, any Stovebolt can be restored.
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Jerry,
I'd bet it's a 6v fan. Maybe someone has a Blue Chip GMC accessory/option brochure? GMC changed all models to 12v negative ground by 1956.
The earlier 6v systems would have been positive ground.
A 6v fan would probably run on 12v negative ground - my guess is that it would be a faster RPM.
Maybe the Moderator will move this to the electrical forum?
| | | | | Joined: Sep 2014 Posts: 120 'Bolter | | 'Bolter Joined: Sep 2014 Posts: 120 | Tim,
My panel is a Chev and the heater is GMC. No telling what year the heater
was made. Fan motors honk right along with 12V negative ground. And the
air flow moves in the right direction.
Hope someone in the electrical forum can help me determine if the motors
are 6 or 12V.
Thanks fur yer hep'
Jerry
1 1951 Chev Panel with a 350 small block, automatic tranny.
1 2004 Chev 2500 HD pickup... stock
1 1950 Chev 5 window pickup; 261 c.i. engine, 4 on the floor.
With lots of time and money, any Stovebolt can be restored.
| | | | | Joined: Jan 2016 Posts: 631 'Bolter | | 'Bolter Joined: Jan 2016 Posts: 631 | It's fairly obvious when the 6 volt fan motor is run on 12 volts.
The 6 volt fan motor pretty much screams on 12 volts. I used two ignition ballast resistors in parallel to reduce the voltage to run the fans at a reasonable speed. | | | | | Joined: Mar 2010 Posts: 10,290 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,290 | If you run that 6 volt heater on 12 volts you will melt the shoes off the ole lady on low speed.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Oct 2012 Posts: 60 Shop Shark | | Shop Shark Joined: Oct 2012 Posts: 60 | Follow-up question. Did the ash try pull handles fit your heater?
mjl | | | | | Joined: Sep 2014 Posts: 120 'Bolter | | 'Bolter Joined: Sep 2014 Posts: 120 | Yes the pull handles I ordered from Classic Parts are exact duplicates of the ash tray pull handles AND the pull handles on GMC hot water heater.
1 1951 Chev Panel with a 350 small block, automatic tranny.
1 2004 Chev 2500 HD pickup... stock
1 1950 Chev 5 window pickup; 261 c.i. engine, 4 on the floor.
With lots of time and money, any Stovebolt can be restored.
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