William Knopf

1956 Roadmaster Carburetor or fuel pump issues

Recommended Posts

1 hour ago, Beemon said:

Maybe not Teflon then,  I concede. The original was braided stainless on the outside, though, as was obviously replaced with rubber hose in William's photos. 

 

William, how does the filter at the carb look? 

I gotta disagree on the braided steel, B.

I've never seen an original with anything other than rubber.

Edited by buick5563 (see edit history)
  • Like 1

Share this post


Link to post
Share on other sites

...and zero snark intended, William. If you don't know what the second half of the fuel pump does, please put the tools down until you buy a shop manual.

 

In my opinion, that box is a fire waiting to happen and I would remove it.

  • Like 1

Share this post


Link to post
Share on other sites

Buick5563, it was just a unique pump. We saw that the line went to the wipers but was caught off guard. 

My 40 LaSalle, 37 DeSoto, 49 Chevrolet, 55 Studebaker, and 33 Plymouth didn't have anything like it. Of course some of these are not stock. 

Very thankful for the support from everyone on this forum. I will be getting a shop manual as all my cars are different. 

Share this post


Link to post
Share on other sites
12 minutes ago, William Knopf said:

It had dried white powder and I cleaned it out. Suggestions 

 

 

It being the fuel pump?   The white powder is old dried up gas and it byproducts.    Put it back together and install on block.   Disconnect the the hose from the pump to the carb.  Connect the fuel tank hose to the newly cleaned pump.   Turn of the engine and see if she will start to pump fuel.   If so, connect to carb.  If not replace  or rebuild pump.  

 

Personally, I would purchase a pump that is ready to go and install.   

Share this post


Link to post
Share on other sites
11 minutes ago, William Knopf said:

Rockauto shows only electric pump for the replacement. Is this the way to go. Would the vacuum for the wipers still function if I took this route? 

 

 

The electric pump should pump through the original mechanical pump and run the car.  Pump should be 5-6 pounds of pressure if I'm not mistaken.    The vacuum portion on the mechanical pump should run the wipers if the portion of the pump is internally ok and...the wiper motor is internally ok.

 

I do not run electrical pumps on mine.   Never had a need to install one.  

 

 

  • Like 1

Share this post


Link to post
Share on other sites
3 hours ago, William Knopf said:

Where do you purchase one?

Try "Then and Now Automotive" in the Boston area. They should have new original type pumps, rebuilding kits for yours, or possibly offer a service to rebuild yours.

 

Good people

 

Jon.

Share this post


Link to post
Share on other sites

Dad just spent an hour waiting on the vapor locked '56 to cool down & start again. He's over 3 hours from home at the rainbow arch bridges on Route 66 in SE Kansas. 

 

A few weeks ago I told him he should install an electric pump. He claimed he'd never had a vapor lock issue in the '56. I told him he's smoking crack.  When your fuel filter suddenly turns bone dry, it's pretty obvious. Any guesses how hot it was under that big, black hood?

 

IMG_6409.PNG.60032a3c287f5b420f8b433ee285a3db.PNG

 

On a side note, he just noticed this clap trap south of the fuel pump. Anyone think that mess is factory?

 

IMG_6410.thumb.JPG.a3e0e02c3b1282fbcb10a5c672042fc2.JPG

  • Like 1

Share this post


Link to post
Share on other sites

Bad thing about stainless braided hose, for any application, is that it's still got rubber inside and that rubber will deteriorate as if the stainless braid was not there.  Stainless braided brake lines can give a firmer pedal feel in race applications, though.  Otherwise, it's main benefit might be increased abrasion resistance, plus neat cosmetics.

 

NTX5467

Share this post


Link to post
Share on other sites
11 hours ago, buick5563 said:

I gotta disagree on the braided steel, B.

I've never seen an original with anything other than rubber.

I may be a bit jaded here, mine came with one. :P

11203168_10153775052895830_4599979796546

 

I just assumed all Buicks were like mine.

Matt, I think someone added that drain petcock.

  • Like 1

Share this post


Link to post
Share on other sites
10 hours ago, Beemon said:

I may be a bit jaded here, mine came with one. :P

Or that was the replacement sometime in the last 61 years.:o

  • Like 2

Share this post


Link to post
Share on other sites

ok guys. We got the Buick running this afternoon. We drove it about a 100 yards in our driveway and it cuts off. Couldn't get it to start back up unless we manually put gas in the carb. Suggestions?

Is it still possibly the fuel pump. 

Share this post


Link to post
Share on other sites

I'm guessing something with the float (needle / seat) not refilling the primary portion of the carburetor IF it started on its own without filling the carb (fuel pump filled it). 

Or clogged line. 

Again, if you put gas in the carb to start it and run the 100 yards, that is what the car will run on with just the fuel in the bowl.

  • Like 1

Share this post


Link to post
Share on other sites

Did you confirm fuel was being pumped by the fuel pump?

Share this post


Link to post
Share on other sites

Is the filter the old pancake style? If so, you might want to take that apart first and give it a good rinse and make sure it's actually passing fluid through. it has one screw that you undo and it should come apart. If that doesn't do it, then it looks like a carburetor rebuild. Before you take it apart, check the sight plugs and see if the bowls are filling up. You might be able to get away with just removing the air horn and seeing if the needle and seat are gummed up. Is this a Rochester or Carter carb?

Share this post


Link to post
Share on other sites
On ‎7‎/‎11‎/‎2017 at 7:38 AM, dons56 said:

Fuel pump on top.  I cut a disc of neoprene when mine leaks... I have found a source for ethanol free gas which is all I buy unless out of town.  Ethanol and neoprene do not play nice together...

 

In another thread, possibly in another AACA forum, the northeastern USA fuel pump rebuilder was noted to use the newest ethanol-resistant neoprene in his rebuilds and kits he sells  It WAS later pointed out that while the particular neoprene will resist deterioration from ethanol, as long as the diaphragm is wet with fuel, but IF the diaphragm is ever allowed to dry out (no fuel against it or in the pump body from non-activity, over time), the neoprene will become brittle and fail as a result.  So, a few dynamics to the fuel pump diaphragm and ethanol fuel.  SO . . . . keep that engine "exercised" even if the car doesn't move.

 

NTX5467

  • Like 1

Share this post


Link to post
Share on other sites

I respectfully agree that the stainless steel braid hose was probably put there "after initial assembly", rather than at the assembly plant.  Until the later 1970s, in the car hobby, stainless steel braid hose was more aerospace than automotive in where it was used.  That was a good 20 years after 1956, so you can figure how far things had come in those 20 years.  Also, two other dynamics.  One is cost, which was certainly more than normal rubber hose.  There would have had to be a VERY strong case to use that more expensive type of hose to justify it to GM's Financial Dept.  Another is that vehicle warranties were much shorter back then, months instead of years, so the factory's liability exposure was much less than in more recent times.  It would also have been much easier to configure a simple metal shield for the rubber hose, if abrasion-resistance was one reason to use SS braided hose rather than bare rubber line.

 

Regards,

NTX5467

  • Like 1

Share this post


Link to post
Share on other sites
4 hours ago, William Knopf said:

Carter

Rochester carbs use rubber tipped needles in the seat that can go bad after a while. If the Carter is original, the needle should be metal. However, you don't know if they've been replaced with rubber or not. Verify the filter flows, then verify the float bowls are dry. If they're dry, then it's time to open the carb. 

Share this post


Link to post
Share on other sites

Rochester and Carter (Holley also) went to the rubber (neopreme) tipped fuel valves about 1963. Before that, all were metal (well, with the exception of a few Carter in the late 1940's that were plastic). The neopreme was, and is, a vast improvement over the metal, even with E10 fuel. The ethanol will cause the steel needles to rust.

 

Jon.

  • Like 2

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...