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I recently sent my fuel pump for rebuild to Fusik and learned that I had an incorrect fuel pump for 1957 Oldsmobile 88 Sedan (No A/C). The fuel pump they sent me is part number 4646VD which VD stands for vacuum delete. My confusion is how to plumb this particular fuel pump which should be correct for my 57. I do see the fuel inlet, and also where I would install the air dome… where my confusion is where to correctly install the outlet meaning fuel pump to carb line. Also I did order new fuel line part number OC5801 (fuel pump to carb). When I mock it, doesn’t quite line up…
Does anyone have a picture showing how to run the line from fuel pump to carb? Close up would be awesome
@Olds64 it was running an electric fuel pump with a Edelbrock carb from the gas tank. My goal is to run of mechanical fuel pump hence why it’s been rebuild and secondly rebuild the original carb to my knowledge. It was included with the car and sitting in the trunk. Which is why I have no visual reference. I do have the shop manual but not much detail in how to run from fuel pump to carb aside from saying gas to inlet and outlet to carb. Still need to do some more research. Also no the line is not close when I mock it. I feel like there’s something missing between the line from pump to carb. In the meantime much to do while I figure out on this old gal
I have looked at some '57 engine bay pictures. It couldn't be much different from my '55 that still has the original line from the pump to the carb. That line, albeit, has got to be most cut-on, changed item on an older car.
Last edited by madmax442.com; Mar 5, 2024 at 09:15 AM.
I guess my confusion is the outlet from my fuel pump. My pump appears to have two outlets as you can see from the pictures I attached above. Does it mean that I can choose either to the carb? If so I never seen a pump that works that way. Only seen one inlet and one outlet.
I ended up having a local shop install it while doing lots of other getting-it-drivable-again work - like carb rebuild, brake system rebuild, etc. Still, it looks to me like both those ports are on the top side of a diaphragm, so they've got to be both air. If you can pin it down to the bench somehow, or get a helper, you should be able to prove that theory by working the cam lever and checking for air going in one hole and out the other, or just trying to plug each/both and feeling pressure/vacuum build up. Mine's been working well by the way. I'm currently putting discs on the front; already converted to dual cylinder master-booster with proportioning valve. Good luck with yours.
I guess my confusion is the outlet from my fuel pump. My pump appears to have two outlets as you can see from the pictures I attached above. Does it mean that I can choose either to the carb? If so I never seen a pump that works that way. Only seen one inlet and one outlet.
Yes, the top ports are for the wiper/washer vacuum assist. That's why they call these pumps dual action (fuel and air pump). I did a diagram of my wiper/washer vacuum system a while ago. Here it is, hopefully this helps.
@madmax442 Thanks for the diagram it is very helpful. On my pump as mentioned, the vacuum ports are eliminated. So I’m okay with that and not a concern, my confusion is which port goes to the carb and where does the other one go?
I saw another one on the web and it had one of the three holes plugged off, one hole as you have it with the pulsator and that leaves the third for the outlet to the carb. I don't think it matters which hole you use for what. You'll need a 90 degree fitting for the line to the carb if you choose either side hole or if the pulsator fits put that in the side hole and put a straight fitting there.
I don't think you have the correct hose type going into the pump. That looks like a power steering line and I'm not sure if it's compatible with gasoline, you might want to check on that. Besides, it having that fitting on it how would you unscrew it in the event you had to change it? It should have a fitting there where the hose slides on and then held on with a hose clamp. Also check the manual to see what size you should be running, 3/8 etc.
I saw another one on the web and it had one of the three holes plugged off, one hole as you have it with the pulsator and that leaves the third for the outlet to the carb. I don't think it matters which hole you use for what. You'll need a 90 degree fitting for the line to the carb if you choose either side hole or if the pulsator fits put that in the side hole and put a straight fitting there.
I don't think you have the correct hose type going into the pump. That looks like a power steering line and I'm not sure if it's compatible with gasoline, you might want to check on that. Besides, it having that fitting on it how would you unscrew it in the event you had to change it? It should have a fitting there where the hose slides on and then held on with a hose clamp. Also check the manual to see what size you should be running, 3/8 etc.
That fuel line to the bottom of your pump looks similar to the flexible line from the frame hard tube to the hard tube on the bottom of the pump. I would not be that concerned about compatibility.
@Supernice88@DFitz thanks for your help and explaining that I can plug one or the other holes. As far as the flexible fuel line, this is the line that was sent by Fusick (part number 11216) also per the shop manual section 8-9, to remove the flex line must be attached to the fuel pump before attaching the other end to the main fuel line. So no worries there.
To run line from fuel pump to carb, below are the instructions I received from Fusick. It shows two ports inlet and outlet with air dome. That’s where I was a little confused about the third port on my pump but as supernice88 mentioned I can plug one or the other hole. Even though when mock the hard line with a 90 degree from pump to carb it doesn’t line up which ever way I try. I think I’ll call Fusick tomorrow and get some clarification if I am missing something here…
Last edited by dangulo4; Mar 12, 2024 at 08:04 PM.
@Supernice88@DFitz thanks for your help and explaining that I can plug one or the other holes. As far as the flexible fuel line, this is the line that was sent by Fusick (part number 11216) also per the shop manual section 8-9, to remove the flex line must be attached to the fuel pump before attaching the other end to the main fuel line. So no worries there.
To run line from fuel pump to carb, below are the instructions I received from Fusick. It shows two ports inlet and outlet with air dome. That’s where I was a little confused about the third port on my pump but as supernice88 mentioned I can plug one or the other hole. Even though when mock the hard line with a 90 degree from pump to carb it doesn’t line up which ever way I try. I think I’ll call Fusick tomorrow and get some clarification if I am missing something here…
It's entirely possible, that at some point in the past, something else was retrofitted. It still should work, just different.
I'd send you a picture of my '55, but it seems different enough to not be helpful. My filter is on the bottom of the pump, not the carb inlet. Good luck.
BTW, my original pump does have 3 ports on the bottom. 1 outlet, 1 plugged, and the dome. The rebuilt unit I now have only has 1 outlet plumbed, no dome. It seems to work just as well.
"It's entirely possible, that at some point in the past, something else was retrofitted. It still should work, just different."
He didn't show the flex line they sent him. On their site it explains that it attaches to the frame rail hard line which screws into the other end not seen in his photo.
Also used Fusick paint, did you put clear coat over the valve cover stickers as well? I just installed my valve covers today so seeing your pictures was awesome!
Over the weekend I received my rebuilt stock carburetor and looks amazing. Because this was not plumbed when I bought the car, I am not quite sure how to plumb the vacuum from distributor to carb and dashpot. To my disappointment the shop manual was very vague and what I could find online was all for J2 setup, not 4 barrels single carb.
Also my 57 olds does not have power brackets so not sure where to plumb the port in rear of carb. See pic below
@OLDSter Ralph your pictures was very helpful for fuel pump to carb and gave me an idea where to plumb what I am missing, if possible would you be able to take pictures of dash pot to carb port, distributor vacuum to carb, and where the rear port line goes to?
Yes, my mistake, I meant @Nomadocyour pictures was very helpful for fuel pump to carb and gave me an idea where to plumb what I am missing, if possible would you be able to take pictures of dash pot to carb port, distributor vacuum to carb, and where the rear port line goes to?
Over the weekend I received my rebuilt stock carburetor and looks amazing. Because this was not plumbed when I bought the car, I am not quite sure how to plumb the vacuum from distributor to carb and dashpot. To my disappointment the shop manual was very vague and what I could find online was all for J2 setup, not 4 barrels single carb.
Also my 57 olds does not have power brackets so not sure where to plumb the port in rear of carb. See pic below
@OLDSter Ralph your pictures was very helpful for fuel pump to carb and gave me an idea where to plumb what I am missing, if possible would you be able to take pictures of dash pot to carb port, distributor vacuum to carb, and where the rear port line goes to?
From the looks of your carb in the picture above, you are going to need a t-fitting for the power brakes and the vacuum for the vacuum portion of the dual action fuel pump/wipers. I just pulled my 4GC last weekend so this is fresh in my mind. On my 4GC the rear port has a t-fitting for power brake vacuum and then the dual action pump. The side vacuum port (passenger side) is for the distributor. I know in '56 they went to the dashpot, so slightly different from my '55.
Last edited by madmax442.com; Apr 23, 2024 at 11:39 AM.
@madmax442 Thank you for the response. Ya so for my situation, I purchased a rebuild fuel pump with no vacuum for wipers from Fusick (pictures above). Essentially the idea here is to go with electric wipers in the future so Fusick sells a fuel pump that deletes the vacuum section of the fuel pump. Secondly, my car has no power brakes so that is why I was/am confused where that port would be routed.. The good news, is I did talk to Fusick and they said I should've received a "carb base plate plug" so that explains what I need to do for the rear port.
Still hoping that someone with a similar setup (no power brake car) can chime in and show how the stock carb is plumed. Thanks again for your input and it helps clear up the confusion from my end.
@madmax442 Thank you for the response. Ya so for my situation, I purchased a rebuild fuel pump with no vacuum for wipers from Fusick (pictures above). Essentially the idea here is to go with electric wipers in the future so Fusick sells a fuel pump that deletes the vacuum section of the fuel pump. Secondly, my car has no power brakes so that is why I was/am confused where that port would be routed.. The good news, is I did talk to Fusick and they said I should've received a "carb base plate plug" so that explains what I need to do for the rear port.
Still hoping that someone with a similar setup (no power brake car) can chime in and show how the stock carb is plumed. Thanks again for your input and it helps clear up the confusion from my end.
Ok, I see. My guess is that the rear port would still be used on a stock setup as all the wiper motors were still vacuum assisted back then (until 1958, pretty sure), otherwise that rear port was just plugged.
Sorry, I have not visited the site for a few weeks.
Here are some photos of how my 57’s vacuum lines run. The main source at the back of the base plate goes to the transverse hardline that supplies the vacuum canister and power brakes
( which you don’t have). Distributor advance also comes off the smaller port in the base plate.
Oh, and I applied the clear to the valve covers before I put on the stickers.
Bill
Sorry, I have not visited the site for a few weeks.
Here are some photos of how my 57’s vacuum lines run. The main source at the back of the base plate goes to the transverse hardline that supplies the vacuum canister and power brakes
( which you don’t have). Distributor advance also comes off the smaller port in the base plate.
Oh, and I applied the clear to the valve covers before I put on the stickers.
Bill
Good morning, I'm new to the Classic Oldsmobile forum. I was looking to learn more about my vacuum situation and came across this post from April 25, 2024. These photos are great and they are most helpful. The pictures below show my set up (no p.s. or p.b.). It seems very similar to Nomadoc's pictures I am referencing - through not as nice. When I got the car it was transported from California and I was aware that I might need to fix some vacuum and electrical issues. I want to reference the short vacuum line in Nomadoc's photos that connects the line at the back of the carb to the passenger side line from the top of the fuel pump - it is a simple short piece of vacuum line with a clamp at either end. In my case the car came with a T. The top of the tee had the water line from the windshield washer pump connected to it, so I removed that, as this was incorrect. I connected my vacuum gauge at the top of that T (got 18/19 in.). After I removed the water line, I removed the T and ran a straight piece of vacuum line and used two clamps, just like Nomadoc's. But then I thought the T was there so it would be easier to check vacuum. I guess there is no absolute right or wrong in some of this and I have two questions:
Is Nomadoc's set up closer to stock/original than mine? Other than more places for a vacuum leak, should I go back to the set-up with no T?
If you needed to check vacuum, where would you connect your gauge?
