Fuel System: Carter bbr-1 6 cyl carburetor

[jclary]

Hey folks, I know we have talked these things to death regarding hard starting, vapor lock, leaking, effects of ethanol, etc. I've given it a lot of thought and while I have been tied up with some long overdue home maintenance projects...I thought I would try a little experiment with the carb on my 1955 E-5 185CI truck engine. I have, for a long time, had difficulty with the truck having to crank over for a long time before starting after it sat for a day or two.

We have discussed, at length, about the modern gas boiling out due to heat retention after shutting down a warm engine. My engine will fire right up quickly if you pour a small amount of gas down the carb. A couple of days ago, I "primed" the carb in this manner and fired the engine up. Once it was running smoothly, I shut it down before it could build much heat. Under this scenario, the carburetor reservoir/bowl should be full to its float regulated level.

Today, I went out to the man cave and removed the top of the carburetor only to find it nearly dry. I can only conclude that the gas is either evaporating at ambient temperature, leaking through the casting, or siphoning down to the fuel pump. I am hesitant to install an electric "priming" pump, just because I don't want to (at this time). Instead, I have one of those old "stand-alone" (as opposed to built into the fuel pump) carter glass bowl type fuel filters. It is "period-correct" for my truck, so I am thinking about installing it at the carburetor inlet.

My thinking is that the bowl will give it a closer back-up reservoir of fuel, and move the fuel line from the fuel pump a few more inches away from the heat of the engine. Any comments or experiences from others welcome.

[bezhawk]

At least, with the glass bowl, you will now be able to see the gas boiling! It's a fuel problem, not a mechanical one. Short of a closed high pressure fuel injection, we will not see things improving.

[Warren Webb]

John, why don't you put a temporary shut off valve on the fuel line at the carb. Start the engine as you have then, after the bowl is full, shut it off again & shut off the fuel line to eliminate the possibility of it draining back. Then check later to see if the gas has evaporated or not. This will tell once & for all if our gas today evaporates that rapidly or not.

[jclary]

Well...after a bit of finagling...including a trip to the parts house fittings bin, I have the glass bowl filter in place. I left the old ceramic element out, since it was dirty, too redundant being that there is already a filter at the fuel pump, and I figured leaving it out would allow for more reserve gas. I did leave the small magnet insert, intended to catch small bits of metal, in place. I was impressed at how "over-built" this Carter brand filter is over some others I have encountered through the years.

I have already fired the engine and ran it long enough to come up to temp. I might drive the truck over to a meeting at the church this evening and see how it does.

Warren, your suggestion is fine, but if there is much siphon back to the tank, I don't think it would be completely back to the tank. The fuel pump is mounted pretty low and the glass filter bowl on the pump stays full. I expect the engine will still require some spinning over when cold merely to fill the carburetor reservoir, however, having whatever amount the added filter holds next to the carburetor hopefully will shorten the time it takes for it to start. I'll report later.

[christophe]

You also could try to use one of these. They are perfect for priming the fuel circuit and easy to install.

http://www.aquilair.com/images/poire-amorcage-petit-modele/poire-amorcage-petit-modele.jpg

[jclary]

You also could try to use one of these. They are perfect for priming the fuel circuit and easy to install.
http://www.aquilair.com/images/poire...tit-modele.jpg

That's funny! I have those on a couple of my boats. We could call it "squeeze and go!"

After spending that time, yesterday, installing the extra glass bowl, I pulled the truck out and washed the barn dust off. I had planned to drive it to a meeting. However, a sudden thunderstorm appeared over the mountains and I had to scramble to get it back inside. Wouldn't you know...it wouldn't fire up again. With the air filter removed, I looked into the throat of the carb as I manually manipulated the throttle. No squirt of gas from the carburetor pump. A quick burst of starter fluid and it fired up immediately.

So...I have determined my problem is two-fold. One...the accelerator pump isn't working, and two...the carburetor bowl leaks down (or gas evaporates to atmosphere)over time. I suppose there is no way to avoid taking the carb off the engine and addressing the accelerator pump. I have two options there. Risk heat stroke in the attic of my shop rumbling through boxes of parts, or heading to NAPA to see if they have a kit in stock.

Oh well...the life of a tinkerer

[(S)]

Do whatever you can to get an original base gasket. They were thick and made of a better insulating material that keeps the heat off of the carb. Stack 2 in there and it will make a difference.

[jclary]

Playing around with this carburetor has been an interesting experience. As these cars age, it is probably a subject all of us with stock six cylinder engines need to educate ourselves in if we expect to keep the vehicles operational. If you are like me, you probably have not given much thought to how they actually work. As long as they perform, you just merrily go about ignoring the little device, not giving much thought about how it magically and mysteriously does it thing. That is...until it begins to falter. Although it is a Carter Bbr-1...I wonder how many variations of the little carburetor are in existence. There are ones with manual choke, automatic choke, flat top reservoir covers, covers with a rib/fin, and applications for cars, trucks, Studebakers, Chryslers, etc.

Yesterday, I found a dirty, grimy, and neglected (patina?) spare manual choke version, just like the one I'm working on, lying on a shelf in a dark corner of an old rusty tin utility shed, shoved up against the back wall of my man cave. I needed to run an errand to town, so I plopped the little carb in an old coffee can and decided to visit my local NAPA store while in town. I am amazed that these guys that work there don't run the other way when they see me coming. However, as usual, one of them asked, "Can I help you?" I half jokingly replied, "You don't look old enough!" After thanking me for the complement, he offered to help anyway. I plopped the coffee can containing the carburetor on the counter and asked if he could supply a rebuild kit. When he asked what it was for, and I replied "Studebaker"...I had everybody's attention, clerks and customers alike.

After over half an hour of great conversation, banter, searching old print catalogs, web site visits, and one corporate phone call, I left with no kit, part number, nor suggestions for the future. Yep...those guys are TOO YOUNG!

I have cleaned the exterior of the old carb so that it is not too dirty to handle. I need to go to town again today...think I'll try another parts store.

[jclary]

Well...yesterday I tried my very dependable old time family owned auto parts store and they couldn't come up with a kit for rebuilding my Carter BBR-1 carburetor either. So, today I climbed into the attic of my two story shop to look through boxes of old parts I have stored there. It must have been 130 degrees and opening the window was not much help. I found several carburetor kits with Studebaker part numbers but none of them seem to be for the little six cylinder single barrel BBR-1. Just as I was about to give up (or pass out from the heat), I accidentally knocked over a box. The lid popped off and exposed a small box labeled NAPA ECHLIN carburetor kit. Part number is 2-5072. A little further examination reveals that it is exactly the correct kit...complete with instructions.

Once I made it back into the cool air-conditioned comfort of my house, I emptied the contents of the box to find the original invoice where I bought it from Early Auto Supply over 15 years ago. Mr Early sold the business and has since passed away. I can't read the date but the price for the kit was $6.26 plus sales tax for a total of $6.51

I looked at the kits offered by some of our Studebaker parts vendors and they want over forty dollars plus shipping. There are some other internet vendors who want over eighty dollars for the kits. I should've bought a dozen of those kits way back when.

[Roger L.]

I found this thread quite interesting. I had a similar experience trying to find a kit for the BBR1 on my M16. I went to my local NAPA store and they were able to source a new custom built kit from a supplier in St. Louis, MO that specializes in early and vintage carburetor kits. It fits several different models of the BBR1 and even had the correct needle valve for an M with a commander engine. It was marked as part no. 2080 the source is labeled AFLA on the receipt. It cost me $48.39. Since then I've been able to get two complete original Carter gasket kits off ebay and one complete original Carter rebuild kit, also from ebay, that includes all the parts that goes in the carburetor. Don't remember the seller or price though.

[jclary]

I found this thread quite interesting....

Thanks for contributing Roger. You and I might be the only ones interested...but with the vast number of these old engines still in use throughout the SDC, others need to pay attention. Sooner or later, these little devices are going to need servicing. I am determined to become proficient in adjusting and rebuilding these little carburetors. Not that I want to be the "SDC go-to guy" for servicing them for others, but for self satisfaction of not having to be at the mercy of anyone else.

After discovering the complete kit buried among some of my own stash of parts yesterday, I returned to the local NAPA store today, kit in hand, to see if they could find a current equivalent using the old kit number. They couldn't. However, after a little more forensic study of the old invoice...I have determined that I bought the kit in 1981. I'm sure now, that I must have bought the kit back then, and instead of using it to rebuild my old carburetor, I probably installed one of the many spares I had and kept(and forgot) the kit.

After leaving the NAPA store, I went back by to my other independent family owned parts store. We used the instruction sheet, that has adjustments for different brands of cars, to work backwards to find a current kit number. Using the "BB" model number, instead of "BBR," we found a kit for a Dodge application priced at $25.00. It will be in tomorrow morning. Since this kit covers both the models, we are hoping the new one will have enough compatible parts to suffice. If so, it will provide a current kit at half the best alternative source found thus far.

I'm all for supporting our Studebaker vendors, however, if my local store can supply a kit at a profit for $25.00 paying others a range of $45 to $89 before sales tax and shipping just don't make sense...even for A non-CASO!

[Roger L.]

These carburetors are really quite simple. Just watch out for the needle valve. One difference between the Studeabaker application and others, mainly Chrysler is the needle valve. My carb on my M16 uses a 1/8" pipe thread to attach the fuel line, Chrysler used an inverted flair female flare fitting. There are also two different bodies and air horns. On one the accelerator pump jet screws directly into the side of the fuel bowl, on the other the jet is behind a lead plug. All kits that I'm familiar with will have gaskets for both but only one needle valve. The accelerator pumps are the same though. I'm not familiar enough with all the models that Studebaker used to know if your needle valve is the same as mine or not. Good luck with your quest.

[jclary]

Just got back in the house from testing the truck after reinstalling the carburetor. After opening up the carburetor and giving it a close inspection...I decided not to do a complete rebuild.

I removed the float, needle valve, and accelerator pump. Using a can of carburetor cleaner with the attached discharge tube, I checked all jets, fluid passages, and air mix passages. Everything was clear with no restrictions. I cleaned some sediment out of the bottom of the reservoir/bowl. I liked the fact that the needle was all metal (no viton) and since it had no visible "seat mark" I decided to continue using it instead of the new one in the kit.

As I had suspected, the accelerator pump was toast. The leather cup was only about half the size if the new one in the rebuild kit. It was also misshaped and the spreader spring was protruding from under the cup. I also worked the linkage that operates the pump and discovered that it was hooked up in a manner that caused the pump linkage to pull the pump piston off center in its cylinder. That is probably what caused the cup to deform and fail over time. It also limited the stroke movement of the pump which probably led to poor performance on sudden acceleration. Connecting the linkage rod to the outer of the three holes (instead of the middle one) gave the piston a straight up and down movement in the cylinder with no binding side motion.

Another problem I found was that the float was set too low. That meant the bowl was always a little low on fuel. Probably not enough to affect performance, but with modern gas so quick to evaporate, that could explain why the bowl was so low after sitting a day or two. After giving the float a proper adjustment, I put it back together. The only new parts are the accelerator pump and gasket. I lubricated all the moving parts and bolted it back on the truck.

One other problem I found not carburetor related, was a leaking fitting on the fuel pump outlet. That 90 degree fitting on the pump outlet needed one more turn. Talk about a difficult fitting to get to while the pump is on the engine...good grief! I used a special tube wrench, conventional open end wrench, adjustable wrench, and an odd angled channel lock style wrench to get that little brass fitting one more turn without collapsing it. Turned out to be the hardest part of the whole job.

After fabricating a new steel fuel line from the fuel pump to the carburetor, I fired it up. It runs great! I let it run for about fifteen minutes, shut it down and went in the house for supper. After about two hours, I went back out to see if it would fire up right away. That is about how long I would be at a cruise in when it would be reluctant to restart after sitting. Again, it started without hesitation. So far, so good. And...I have enough left over kit parts to build some of the old used spares I have lying around.

If I can only figure out how to make my own accelerator pump cups. (CASO to the extreme)

[altair]

carb woes

Just got back in the house from testing the truck after reinstalling the carburetor. After opening up the carburetor and giving it a close inspection...I decided not to do a complete rebuild.

I removed the float, needle valve, and accelerator pump. Using a can of carburetor cleaner with the attached discharge tube, I checked all jets, fluid passages, and air mix passages. Everything was clear with no restrictions. I cleaned some sediment out of the bottom of the reservoir/bowl. I liked the fact that the needle was all metal (no viton) and since it had no visible "seat mark" I decided to continue using it instead of the new one in the kit.

As I had suspected, the accelerator pump was toast. The leather cup was only about half the size if the new one in the rebuild kit. It was also misshaped and the spreader spring was protruding from under the cup. I also worked the linkage that operates the pump and discovered that it was hooked up in a manner that caused the pump linkage to pull the pump piston off center in its cylinder. That is probably what caused the cup to deform and fail over time. It also limited the stroke movement of the pump which probably led to poor performance on sudden acceleration. Connecting the linkage rod to the outer of the three holes (instead of the middle one) gave the piston a straight up and down movement in the cylinder with no binding side motion.

Another problem I found was that the float was set too low. That meant the bowl was always a little low on fuel. Probably not enough to affect performance, but with modern gas so quick to evaporate, that could explain why the bowl was so low after sitting a day or two. After giving the float a proper adjustment, I put it back together. The only new parts are the accelerator pump and gasket. I lubricated all the moving parts and bolted it back on the truck.

One other problem I found not carburetor related, was a leaking fitting on the fuel pump outlet. That 90 degree fitting on the pump outlet one more turn. Talk about a difficult fitting to get to while the pump is on the engine...good grief! I used a special tube wrench, conventional open end wrench, adjustable wrench, and an odd angled channel lock style wrench to get that little brass fitting one more turn without collapsing it. Turned out to be the hardest part of the whole job.

After fabricating a new steel fuel line from the fuel pump to the carburetor, I fired it up. It runs great! I let it run for about fifteen minutes, shut it down and went in the house for supper. After about two hours, I went back out to see if it would fire up right away. That is about how long I would be at a cruise in when it would be reluctant to restart after sitting. Again, it started without hesitation. So far, so good. And...I have enough left over kit parts to build some of the old used spares I have lying around.

If I can only figure out how to make my own accelerator pump cups. (CASO to the extreme)

I can relate to your story in every detail, I went through the exact procedure to find the failed accelerator pump and the float level too low. A curious point, some guys talk about fuel evaporation and fuel syphoning. How can the fuel syphon back to the tank and overcome the closed return valve in the fuel pump and the needle valve in the carb? After shut down the remaining fuel in the carb has very limited access to atmosphere and that being manly through the jet system it seems to me it would take months for the fuel to evaporate, unless there was no fuel in the bowl in the first place because of a maladjusted float level. I don't know how a float can get so out of wack unless somebody has taken plyers and bent the adjustment, or when removed was mishandled and got bent on the bench. When these units are apart the float adj is vulnerable to accidental bending. A common mistake is where the carb is flooding as a result of a contaminated needle assembly and the float gets the attention instead. After the flooding continues the needle and seat is replaced and the float remains too low. And the chase is on. Good story well written Dave