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| | | | Joined: Oct 2012 Posts: 101 Shop Shark | | Shop Shark Joined: Oct 2012 Posts: 101 | i got a 235 engine out of a 3800 and didnt notice til
i got home fuel pump is double and one section goes
to hollow bolt on fuel pump to block. the other
outlet off fuel pump i dont know where it went.
i saw a picture online of a 1941 car with a double
but cant see where the lines go.
was this some kind of extra oil circulator/filter ??
i am putting the engine in a 1/2 ton
thanks | | | | | Joined: Mar 2010 Posts: 10,282 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,282 |
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | rwb,
Can you post links to photos?
| | | | | Joined: Oct 2012 Posts: 101 Shop Shark | | Shop Shark Joined: Oct 2012 Posts: 101 | i will try to post photos.
the pump had crankcase oil in it and the bolt
was special replaced reg fuel pump bolt.
had a hose going from one side of the double pump
that went to that bolt.
thanks
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | rwb,
Someone else recently reported a hollow bolt holding the fuel pump to the block. I think someone might have posted something about it providing lubrication to the lobe on the camshaft?
Was/is there a tube/line going into the hollow bolt? Where does that line/tube connect at the other end?
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | TC, I have a 1961 235 with a pump with that bolt. I replaced it. I think there was a rubber hose connected to it. I don't know where the hose went, always thought that hose bolt was a vac bypass or something related to wiper vac. I have seen that you have the largest library of Chevy info in the nation, you mean you don't have a pic or instructions for that pump bolt hook up? That's impossible! 
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Feb 2008 Posts: 212 'Bolter | | 'Bolter Joined: Feb 2008 Posts: 212 | My 58 had that bolt on it also but my rubber hose had been cut and was just hanging over the engine, I did also have the dual action fuel pump. | | | | | Joined: Oct 2012 Posts: 101 Shop Shark | | Shop Shark Joined: Oct 2012 Posts: 101 | i didnt notice where the other end went when we
pulled the engine.it was a old state of alaska rig.
thing is has to be oil right as bolt with hose barb
is one of the 2 holding fuel pump.
i know i can just block it off just curious what
purpose was.
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 |
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | Some GMCs had a bolt there for the oil filter return. However, it had a threaded hose fitting. Never seen one like Bart posted or seen one on a Chevy. | | | | | Joined: Mar 2010 Posts: 10,282 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,282 | Could it be that this hose barb/bolt was connected to the input side of the vacuum pump, providing crankcase ventilation via the pipe going to the intake?
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | The breather/draft tube is right next to the pump. That is a big pipe, why need more? Hole in bolt is less that 1/8.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
Does anyone know the location of the attachment at other other end of the hose/line that goes to the hollow attachment bolt for the fuel pump (in 59 & 58?)?
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | I have been working on that with no luck yet.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2010 Posts: 10,282 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,282 | The breather/draft tube is right next to the pump. That is a big pipe, why need more? Hole in bolt is less that 1/8. Bart, it needs to be pointed out that I do not know what I am talking about and that I am just throwing out random ideas. I don't drink any more so my answers sound stupid to ME sometimes. Anyway... the draft tube doesn't function at all at a full stop, and not much at all until some speed is built up. I was stabbing at the notion that a vacuum pump could be a neat way to evacuate fumes from the crank case at idle, when the downdraft tube isn't providing that task then. A vacuum pump on a 235 of this vintage seems odd if the trucks had electric wipers by then (?). Carl
Last edited by 52Carl; 03/21/2014 12:10 AM.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Carl, "...Why need more?" ...does sound like a bad remark, sorry. Did not see it that way, just meant it as a wonder why you would need more (a rhetorical question). You are absolutely correct about tube not good til about 15MPH. The 59's did have vacuum wipers. Electric, I believe, was an option. I have a stock 59 with vac wipers. The thread I linked is about a 58 with vac wipers and a hollow bolt. I PM'ed him to see if he ever figured it out. The 58 manual talks about vac wipers and that hollow bolt but the wording associated with it is "crossover hose" and "check valve assy". Hard to understand what they mean by crossover hose, wish they would have said crankcase vent or pressure relief or ? My apologies again. I started to feel the same way about
"Isn't there a cardboard tube on the high beam bulb to prevent that light leakage?" to my silly suggestion, but I know you and took it correctly. Maybe the cardboard tube is crumpled, shifted, leaking light, missing...
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2010 Posts: 10,282 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,282 | Hey Bart, you might be on to something with the "crossover hose and check valve assy". If the crossover hose ties into the vacuum pump, it would pull fumes out of the crankcase. The question now would be, where would the fumes go once sucked into the pump? The mention of a check valve assy reeks of PCV to me. As far as apologies go, I am not owed any from you, I probably owe more, in general, than I am due.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | if the dual acting fuel pump were pulling fumes from the crankcase, it'd be sending them to the vacuum wipers .... not likely
Bill | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | We don't know "crossover" from where? and we don't know if flow is in or out of the hollow bolt. We don't even know if the hollow bolt has anything to do with the pump. Someone has to know what this is. I have searched the internet quite a bit looking for wording and pictures. Nothing yet except the repair manual verbage and the fact that one vendor sells two dual action vacuum wiper pumps, a 52-57 and a 58-62. A design change.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2010 Posts: 10,282 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,282 | if the dual acting fuel pump were pulling fumes from the crankcase, it'd be sending them to the vacuum wipers .... not likely
Bill My hair-brained, Imagination-land notion doesn't have vacuum wipers. At anytime, anyone is welcome to tell me to shut up, and a will.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | We are all brainstorming, no one is excluded. Maybe our hint is from the guy who actually has one? (OP)
"...pump is double and one section goes
to hollow bolt on fuel pump to block." Keep in mind it could have been mis-hosed, if that is a word.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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