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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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| | | | Joined: Jun 2006 Posts: 35 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2006 Posts: 35 | I would like to install my double action fuel/vacuum pump so my wipers don't slow down so drastically. How are the vacuum lines routed? Is the engine vacuum still used? Any advice or comments are appreciated. Thanks, Possum | | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | I've considered doing the same with my 38. I've not seen any "official" instructions but I would imagine the vacuum line would just route the path that would keep it out of the way. I would route it through the firewall hole the current line occupies. I can't imagine the engine vacuum being used for the wipers anymore. I'm sure that if I'm wrong someone will correct me. 
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Dec 2005 Posts: 324 Member | | Member Joined: Dec 2005 Posts: 324 | The double action fuel pump has two diaphragms, one pumps gasoline the other supplements the vacuum. The exit line from the vacuum side goes to manifold vacuum. The other line goes to the wiper motor.
"It ain't a truck if you can't hose out the cab."
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | You still need to use the manifold vacuum also. The pump is an auxilary. Plumb it like Chester says.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | 46possum,
Enclosed is a great link that even has pictures. I have seen questions on this before, and it seems there are several different pumps and a few varying ways to hook them up. Take a look!
http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=22;t=003936#000000
Stuart | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | There are diagrams in the factory assembly manual. Should be about the same for all years. | | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | See, I told ya I'd get corrected if I was wrong. 
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Jun 2000 Posts: 2,773 'Bolter | | 'Bolter Joined: Jun 2000 Posts: 2,773 | Another option is to install a vacuum tank in the line to the wipers. It needs to have a one-way valve so it doesn't bleed down. There are lots of them at the junkyards, most all modern cars have them. Only problem is finding one that looks like it belongs in an old truck.
Fred
52 3600
69 C-10
| | | | | Joined: Jan 2005 Posts: 1,602 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 1,602 | Hey I have one of those double action fuel/wipers pumps in my garage that has never been used. If anyone wants it, let me know.
I bought the wrong one and had it taken off my truck before I put gas in it. You can see it in the picture link below as well as the new one single action I bouight to replace the one I'll be letting go. I made a mistake so somebody might as well put it thier stovebolt.
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