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#70228 12/18/2006 12:49 AM | Joined: Jul 2005 Posts: 13 New Guy | | New Guy Joined: Jul 2005 Posts: 13 | My all-original 1941 Chevy truck has the special combined fuel and vacuum pump, that was made for the larger trucks. It's a big help with the wipers when going uphill. Since I had the pump rebuilt a few years ago, it has been leaking motor oil profusely. The leak comes out of a pair of drilled, 1/8" holes that are in the body of the pump, on the side facing away from the motor. Can anyone tell me what these holes are for? Would any harm come from blocking them up?
Bob Acland | | |
#70229 12/18/2006 1:39 AM | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy Bob, I'm not totally sure from your description, but I think those holes are the vent holes above the diaphragms, which allow air to move in and out of the housing as the diaphragm moves up and down, if that's what they are then you can't plug them, hope that helps. | | |
#70230 12/18/2006 2:43 AM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Bob Acland,
I wonder if this is more common than folks think. I did a search and found this post.
http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=2;t=011368#000000
Stuart | | |
#70231 12/18/2006 4:13 AM | Joined: Feb 2004 Posts: 29,805 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,805 | Leaks from those holes means there are some seals that have failed, or weren't replaced when the pump was rebuilt. The linkage between the diaphragms must be lubricated by crankcase splash, but there shouldn't be enough oil in there to leak out. Either get another pump, or go back on the "rebuilder" who caused the problem and make him fix it right!
Also, if your crankcase vent system (road draft tube, etc.) is clogged, crankcase pressure will cause a leak there.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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#70232 12/18/2006 11:46 PM | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Pluging holes like that are like useing a cork to stop diarea.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | |
#70233 12/19/2006 1:51 AM | Joined: Oct 2000 Posts: 112 Shop Shark | | Shop Shark Joined: Oct 2000 Posts: 112 | Yep, I don't have double style just single with bowl on top only mine leaks from pin hole that holds diaphram and lever together. not bad but drips a little, I rebuilt it myself and guess the old casting was worn to much, IE> pin is to sloppy, works good but leaks a little. Gotta get a newer one.
Jbennett
40 burb | | |
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