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| | | | Joined: Apr 2012 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2012 Posts: 23 | I have a casting number of 3835590, pretty sure it is the right intake manifold. But it has a larger than normal attachment for vacuum. The male portion is screwed in to manifold per normal, the female where you would attach a hose to it are not NTP, just a bit larger than 1/4" NTP. Possibly compression? What would that thing be? Better question, how would I hook up original vacuum WS wiper motor? Am I better off to take it out and get a standard item, and where would I find one?
1955 1st Series 1/2 ton
| | | | | Joined: Jun 2012 Posts: 1,749 'Bolter | | 'Bolter Joined: Jun 2012 Posts: 1,749 | My 235 has an elbow with a slip tube extending from it. No hose barb or fitting. If I had vacuum wipers I would use a canister to buffer the vacuum and I would be looking for the double action fuel pump to supplement the vacuum. Just use a hose clamp to secure the line and you should be OK.
Steve H
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | take it out and go to a plumbing supply store to find something appropriate to fit - if nothing there, check the auto parts stores, as Steve says, commonly the wiper hose is attached by clamping
Bill | | | | | Joined: Nov 2011 Posts: 1,611 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 1,611 | The larger hole in the intake manifold may be to accommodate a line nut which holds a very short section of 1/4 inch steel line (just like brakes). Rubber hose is slipped onto the steel line and clamped. | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 |
The larger diameter vacuum line hole in the intake manifold was probably for/from a truck with a hydrovac and a 2-speed-rear selector and wipers, or there might have been a larger vacuum hole in later manifolds?
I have some steel or brass vacuum wiper fittings that fit that larger hole, and some brass fittings for the larger trucks that used hydrovac and 2-speed-rear that fit the larger hole.
A brass reducer adapter should be available at an auto part store or a hardware store.
I'll post photos, if that would help.
| | | | | Joined: Apr 2012 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2012 Posts: 23 | Tim,
pictures always would help. I tried brass in the outlet of the insert, it isn't NPT. I suppose compression. Makes sense if it was going to brakes or something more safety related. I may be able to get a compression / NPT reducer. Really, my biggest issue is I am trying to keep this thing as "correct" as possible. And I know that if I don't have this right, it is going to bug the crap out of me. I would really like to get right part that screws into the manifold for the truck its on.
1955 1st Series 1/2 ton
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Here is a quick-and-dirty web page that shows the intake manifold with 1/2" NPT hole (same GM part number as yours). Also shown are various fittings that I have accumulated (they are not for sale) and some images of fittings that would work with the wiper vacuum hose. Make sure the hole in your manifold is 1/2" NPT (it most likely is). NAPA and Grainger should have the brass fittings (or, be able to get them). If you have a fitting in your manifold, you might be able to find a brass barb hose adapter for your vacuum hose. | | | | | Joined: Apr 2012 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2012 Posts: 23 | Are all of those "standard" issue? I have the one at the bottom of the picture, I guess it is 1/2" NPT x compression?
You think this would fit as a one part replacement?
http://www.ebay.com/itm/380863173244?_trksid=p2055119.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT
1955 1st Series 1/2 ton
| | | | | Joined: Apr 2012 Posts: 23 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2012 Posts: 23 | I should probably just get a brass 1/2" plug and some copper pipe and make one.
1955 1st Series 1/2 ton
| | | | | Joined: May 2006 Posts: 423 'Bolter | | 'Bolter Joined: May 2006 Posts: 423 | I just had to deal with the same. The 235 manifold I found here on the site had a 1/2" solid plug, and I am far away from proper parts. I found a short section of former steel gas line, bent 90 degrees. I drilled a hole in the center of my 1/2" plug and glued in the gas line with JB Weld. Then rubber line to the wipers. It works so far.
Karl
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe | | | | | Joined: May 2006 Posts: 423 'Bolter | | 'Bolter Joined: May 2006 Posts: 423 | As far as I am concerned, anything that looks like it might have been done on the farm with whatever is at hand is "correct."
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe | | | | | Joined: Mar 2010 Posts: 10,308 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,308 | As far as I am concerned, anything that looks like it might have been done on the farm with whatever is at hand is "correct." Now that's the spirit I can relate to! Many of these trucks were used as farm implements that kept the farmer out of the weather.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Apr 2006 Posts: 506 Shop Shark | | Shop Shark Joined: Apr 2006 Posts: 506 |
-Tom
1950 Chevy 3100 w/ 1956 235
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