Simple Carb

[wa1udg]

Spent some time after the "big" storm helping  neighbors get their gen sets running.  (since I run mine dry with some gas stabiliizer in the last batch I have no trouble)  Some REAL simple carbs on those old L Head Briggs engines, but a nice laver if gum doesn't help matters.  

[Barry]

I suppose engines that are expected to run on a constant or very narrow load range can have a very simple carb.  Bucket with a calibrated hole might work.

[Dizerens5]

Do any other UK members (getting old!) remember the Wal Phillips fuel injector? Fitted in the late 1950s in place of the carb, by some of the boys with strong right wrist. I never did discover how it worked. It certainly was not a true injector like today's kit. But I do know that it depended to some extent on a primitive kind of fuel pressurisation -- that caused by the weight of fuel in the tank! So I suppose it had some kind of injecting function, best I believe with the tank about half full. But I never knew anyone who had one fitted.

[Dizerens5]

And while I'm on the subject, how about this little device on a Jawa, should I call it the poor man's supercharger? Sorry the photo is pretty faded, I took it in 1959...

[Barry]

Do any other UK members (getting old!) remember the Wal Phillips fuel injector

I do indeed and had just thought about them when I joked about a bucket with a hole in but couldn't remember the name.  I had the same curiosity about how they worked and suspect the bucket analogy is not that far off.

I seem to remember they were an impressive looking rectangular shape.

Well I was wrong about that just found an article with a  picture http://www.racinglambrettas.com/howthetdidit/walphillips.html

Interesting reading. They would be a perfect match for airheads as you absolutely could not leave the fuel tap open without emptying the bucket into the engine.  

[Dizerens5]

Good grief Barry, it sounds like keeping a dog and barking yourself. No wonder most of us stayed with the good old Amal. Perhaps it worked better with scooter engines. I would guess in 1960 a pair of high-bump pistons would have done as well and been easier to fit and set up!

[montmil]

Do any other UK members (getting old!) remember the Wal Phillips fuel injector? Fitted in the late 1950s in place of the carb, by some of the boys with strong right wrist. I never did discover how it worked. It certainly was not a true injector like today's kit. But I do know that it depended to some extent on a primitive kind of fuel pressurisation -- that caused by the weight of fuel in the tank! So I suppose it had some kind of injecting function, best I believe with the tank about half full. But I never knew anyone who had one fitted.

Back in me college days, I worked at a BMW, Triumph, Honda and Yamaha dealership. Among other skills learned, I did fit a pair of the Wall Phillips "injectors" to a customer's new Bonneville. There was a simple, tapered, flat side needle and orifice (jet) along with a flat carb slide. A fuel head-think full tank of gas- was necessary for decent ops. No carb icing as there was no venturi. Thus, no carb heat system required.

BTW, an identical slide carb like the Phillips is still sold today under the Posa brand name. Popular on aircraft, I flew one on a self-built, VW-powered, composite, 2-place Experimental Category aircraft that I built. I835cc and 190 mph two-way average with two souls on board. No fuel pump but the carb was on the bottom of the engine -updraft- with a 12 gallon fuel tank up above. Plenty of fuel head pressure simulated a fuel pump. Worked very well. Stone axe simple, it was.

Monte

[wa1udg]

Always seemed to me that the Bosch CF mechanical injection system was based on the CV carb, only the  airflow through the "distributor" was used to control the fuel flow rather than vacuum above the piston.  That system didn't break much, the only  troublesome part was the heated cold engine enrichment valve.  

[Barry]

Always seemed to me that the Bosch CF mechanical injection system was based on the CV carb, only theairflow through the "distributor" was used to control the fuel flow rather than vacuum above the piston.That system didn't break much, the onlytroublesome part was the heated cold engine enrichment valve.  

Sounds like the Bosch Ke mechanical injection I have on my old Merc. It's a very simple system and much like a CV carb in that when the throttle is opened wide the airflow plate lifts and adds only as much fuel as the engine needs. The electronic bit just tweeks the mixture for cold starts, overrun shutdown and acceleration enrichment. The black box can fail and the car will still drive. Never had any problems with it in 17 years.

[Semper Gumby]

AMAL MK 1 Concentric is about as simple as you can get.  

Can't imagine having to "tickle" an R65 though...

I'd love to have proper fuel injection on the BSA's and the R65.

[suecanada]

Gotta say I love fuel injection for the simple reason that warm up is so much faster...I'm off and away right away with the rest of the group I could be riding with. LRB takes some time to be assured he won't stall and cause grief in tight situations. But I can't fix it! Now the new to me DR200SE Suzuki dual purpose bike I got from Micatech wouldn't run without choke on full and couldn't take any throttle. So I got brave and did my very first carb take-off and clean. The first try I couldn't get the pilot jet out. I could see it had a slot for a screwdriver but.... In fact all the phillips head bolts were impossible for me to move but Derek got them out for me on the bowl and top dome. I replaced these with hex heads. Next day I really wanted to ride the bike so I took off the bowl again quickly in situ and got that pilot jet out! Took a 10X magnifying glass to see that the tiny orifice was not round. Soaked in carb cleaner and took a nylon really thin brush bristle and poked it through the jet and turned it around in there till I could see it was round. Viola! The bike runs great now! Even rode my very first gravel trail and remembered from way back how much I like the feeling of the rear tire weaving as it bites and claws  into the gravel going up a hill.
So to me learning about a simple carb (with a diaphragm) paid off big time.

[Barry]

Can't imagine having to "tickle" an R65 though...

You know as my enrichers don't work that well I wouldn't mind if Bings did have ticklers ... leaving aside the smelly finger syndrome.

By raising the fuel level for a cold start which then falls back gradually to normal as you ride off they are a perfectly simple form of automatic enrichment.

[Motu]

I used to have a couple of Wal Phillips fuel injectors - pretty crude and not easy to set up. I only tried them a couple of times on some bikes,and noticed no increase in power,but a huge increase in fuel consumption. I don't seem to have them anymore....I collect a lot of junk and seldom throw stuff away,but I must've given them to someone.

[bubby-joe]

I still have one old Posa fuel injector from the early 70's in 32mm. flange, gravity feed, one moving part and all the calibration needles and the alignment tool just turn on fuel on kick and go.  I had it on a harley 45 to replace a badly leaking linkert worked great at the time.  Idle to go like a kid's rocket with no flat spot, great for a devil sled.  I'd like to find another one for my R-65 to replace my 32mm. bing's.

[tvrla]

I think I've got a couple of them around here somewhere. Came with a 450 Honda basket case I got back in the 70s. I'll see what size they are - maybe they'd work for you bubby-joe.