Fuel evaporating from carbs and lines when engine is left standing a long time

Do a search for "rotary fuel pump" we talked about this issue sometime ago on the list.  You'll find some great comments from those who lived with this issue or click here fuel pump in series thread 

Yes, an electric, preferably rotary, fuel pump will cure this problem.

Turn on the ignition to start the pump, count to 10 or 15, then pump it 5-6 times with the gas pedal and then hit "start".

Should start right up (with all of the usual puking and coughing that Dells do when started cold).

CB's rotary fuel pump is a good fit.

Gordon;

What is the PSI requirement for Dells?

carmodymichael posted:

I have a 1600 engine with twin  Dellortos. I have a stock mechanical pump. My Speedster is often left standing for anything up to a few months. Even after a couple of weeks though, I have to make a number of attempts to start the engine before fuel gets through and the engine fires. I presume the fuel in the carburettors and lines has evaporated. 

Some people have said that an electric fuel pump shall solve this problem. 

What do you think?

Mike

Drive it more so the fuel doesn't evaporate.  Decrease the number of days between drives until the problem goes away.

My work takes me away. My wife does not want to run this vehicle whilst I'm away. Life isn't always easy.

Art- Dels and Webers like 3- 3 1/2 lbs. Any more can push fuel past the needle/seat assemblies.

Michael, this is a safety feature designed into these cars so that your wife won't be out driving around in the Speedster while you're gone.

Have you ever noticed how guys are drawn to this car like a magnet? Now imagine how that would work if it were being driven by an unaccompanied woman.

Balky carburetors were placed on this earth for a reason.

Do NOT ever let the wife near the speedster!

The current owner of my old speedster goes through this twice a year when she leaves town. Thus, I always have the time to help her and drive my old car...

Thanks Al

Art

Bosch…anything...and a hard start

 Last fall I ran out of 600 grade wet and dry paper …so instead of cleaning up my distributor rotor, I just replaced it with a “bosch” item…a few weeks later, I am about to go out on one of our air-cooled gang “scare the neighbors” speed-run…and all of a sudden I have a real hard cold start situation!

 Never trusting bosch…I scratch my head and look around…a week later on a whim, I pull the rotor and remembering the nightmare rotors on the bosch distributor Lamborghini Jalpas, I check for continuity…and guess what…a big 5000 + Ohm resistance in the electrode span !

 Since I don’t run CD boxes, the small voltage boost provided by the Pertronix or Compuspark  op-amps is drowned out by the huge resistance and all of a sudden 8,000 volts and maybe 20 milli-joules of energy is trying to start the fuel as it dribble-drabbles down the long inlet track to the cylinder head !

 Far from ideal…so check your rotor !

  ReV

Bosch offers rotors for our distributors in both resistor and non-resistor types.  

The resistor rotors were used for a while as a way of reducing spark noise on car radios, just like resistor spark plugs or resistor plug wires.  The trouble is, you only need ONE of those (rotor, wires or plugs) to reduce spark emissions, not two or three of them.  I've seen quite a few VW engines running resistor plugs, resistor wires and a resistor rotor.

The resistor rotor usually has a trough of epoxy between the center disk and the rotor tip.  They hide the resistor in there and "pot" it in epoxy.

The non-resistor rotor has a solid metal strip between the central disk and the rotor tip (the disk, strip and tip are usually all one piece of metal).

If you're running a higher-powered coil (40,000 volts or higher) it might have enough "Zap" to fry that resistor in the rotor.  In that case, the solid metal rotor is the way to go.

In the Beach Boy's FUN FUN FUN case it wasn't his wife but his daughter who escaped with the sports car!

Meanwhile, how did this thread get any idea that there was a rotor arm, distributor problem?????? The car runs great once it's up and running! I was looking for people who had experience with the electric fuel pump and extended standing. Thanks for the advice everybody. I shall think about the best pump for the job. As always, the pump itself is only one aspect. There's a relay, wiring routing, putting a plate on the stock body hole on the block etc etc.

Gordon? Good to see you're still a Resident Guru. Hope your Speedster gets a lot of running. How many years now and how many reinventions of this website have you been helping people here?

Thanks for the help.

Mike

Ahhh....Springtime in Derby!  You guys drying out yet?  I heard it's been a bit wetter than normal this past winter.  Mind you, I only hear from guys in Windsor and Feltham, these days, and the odd-emails from Cork or Limerick, Ireland.  I keep thinking it might be nice to attend Silverstone, but haven't been (yet!).

Been through 12 years and two or three iterations of this site, and the three years on the Speedstershop, but that's it.  Shop Talk Forums and the Samba are good, but things can get testy/opinionated over there at times.  Also hung out on VWVortex when I was putting my late brother's Sirocco Callaway back together and those folks were great.  Used to do the same thing for a living, helping people sort their way through Enterprise Computer Storage when I was still working...

Ask around about the available pumps over there.  Some of the solenoid pumps make a LOT of clacking noise, others are quiet.  The rotary pumps (CB, Carter, Mallory, etc.) are pretty quiet.  Make sure you stay under 3-1/2 PSI and you'll be fine.  Some people run fuel pressure regulators, some don't.  The CB pump sits at 3-1/2 PSI and doesn't need a regulator on Dells or Webers.

Cheers, Mike!

It sounds like Michael's engine is running just fine with the mechanical fuel pump, once it starts.

So, here's another suggestion that's a bit more Luddite (from a champion of all things Luddite). Why not hook up one of those 'security' switches under the dash that cuts out power to the coil? It would be a lot simpler than a new electric fuel pump and block-off plate.

If the car's been sitting more than a week, just throw the switch and crank the engine for about 10-15 seconds. Then, flip the switch on - and voila! (or 'Bob's your uncle!' where Michael lives).

I was lucky enough to have a mechanical fuel pump that tested right at 3 psi when we put in the new engine, so haven't had to install an electric pump. My solution to dry carbs is to just start the car once a week if it hasn't been driven.

And oh - here's another advantage to the Luddite way. After sitting a few weeks, most of the oil has drained back into the sump. A little slow cranking will circulate the oil some before the engine fires.

What could possibly be easier than a rotary fuel pump?  I'm not wild about grinding away on an engine to get the float-bowls to fill. With a rotary pump, there's no need for a regulator, the pump will support up to 200 hp, and the car starts right up after sitting for a couple of weeks (just as Gordon described: turn on key, count to 15, pump accelerator, start car). It's pretty hard not to love something so clearly superior, Luddite or no. 

A nice side benefit of ANY electric pump is never running the chance of filling your crankcase with gas when the (east Asian) diaphragm in the mechanical pump goes bad (as it most certainly will). A nice side benefit of not filling the crankcase with gas is not diluting the oil and galling the bearings on start-up. A nice side benefit of not galling your bearings on start-up is saving a few thousand bucks for a new engine. A nice benefit of saving a few thousand bucks on a new engine is staying in love with your car and not selling it at a multi-thousand dollar loss.

Sometimes you've got to spend a little bit to save a lot.

The CB pump is a repackaged Carter pump available on Amazon for 30-ish bucks (I think I got two for less than $50 a few years back). A block-off plate is less than $10. Wire off the coil positive if keyed power is too difficult for you, and Bob really IS your uncle.

I'm the resident retro-grouch, but even I know something better with no downside when I see it.

I recently wired up the Carter from Amazon. Came with a fuel filter. I found keyed power on the ignition switch. The lug I tapped into shuts off the power while "cranking" the engine. Returns the power when you stop cranking.

Turn on the ignition for 10/15 seconds so the float bowls can fill. Pump the throttle as you crank it. Giddy'up.

I pulled 12v constant from the battery. Fused 30amp 10ga wire to a 30 amp relay. 12ga (fused lead) signal from the ignition to a relay. 10ga from the switched side of the relay to the pump. Soldered everything. Grounded everything properly.  

I spent more time worring about wiring the thing than it took me to actually do the work.

Stan, reading between the lines here, I sense that you're not a fan of mechanical fuel pumps.

Were you betrayed by a mechanical fuel pump in your formative years? Or perhaps there was an incident of galled bearings later in life that's left you a little bitter? I know how a single unfortunate episode can profoundly affect our whole outlook on life. I still don't like to talk about why the mere sight of a red Volvo can ruin my day.

If this is the case, I apologize for any insensitivity I may have shown you inadvertently in the past. And I'd like you to know that I'll always be here for you.

Your friend,

- Mitch

Hi. I have a Chesil too. I now have a electric fuel pump (of the type you picture - it's not a rotary - and is American made, I'm told used for aircraft) I have the same problem with leaving the car and evaporation. My method is to turn the ignition for a few seconds prior to actually starting (have webers) just letting the electronic fuel pump fill the lines and float chamber. Still takes a few turns from leaving for a few weeks but OK. My carbs are recommended as max 3 psi, but I've found the regulator turned down to 2- 2.5 psi works fine. Too much pressure can make the float chambers overflow.

No need for one of those new fangled electric fuel pumps that help prolong the life of your starter and make starting easy after your car has been sitting or even starting your car every week just to bring fuel to the carbs and shortening bearing life. All you need to do is pick up one of those hand operated rubber bulb priming pumps* from your local boating supply and install it on your fuel line back by the engine for easy access. Then when you want to start that long sitting engine just open the rear lid, give that bulb 5 or 6 good pumps and you're ready to go. I must be a luddite?  

*this item may be a fire hazard when installed improperly

What an amazing topic...every VW based pan or Spyder for that matter has a gas tank higher than the mechanical pump !

So...there is always fuel at the firewall and in most cases at the mechanical pump.

Since the fuel is already there it takes 2-3 seconds for the first carb's float bowl to have fuel, and if you have a split take-off at the firewall 2-3 seconds for both bowls to have enough fuel to support combustion.

 ReV

If you owned a VW Type 1 in your formative years and drove the hell out of it, like we all did, you have had a vapor locked mechanical fuel pump. Need I say more. 

Yinse can say more...or yinse can say less

My family had a brand new 1957 Karman Cabriolet and several other VWs until about 1974 In Bronxville, NY . No one I have ever met on the East Coast ever mentioned "vapor lock" on a Type 1 VW motor !

 It's a Salton Sea thang

  ReV

Did they have stock motors or bigger displacement dual carbed motors?

majorkahuna posted:

If you owned a VW Type 1 in your formative years and drove the hell out of it, like we all did, you have had a vapor locked mechanical fuel pump. Need I say more. 

 

^ This is real, and it's a buzz-kill. Noel hit this one right on the head.

"Hey honey, lets just hang out beside the road in the middle of this corn-field for an hour or so while the fuel quits boiling in the line".

Look, I'm as analog as the next guy (probably more so, if the next guy in an average "merican), but I'm struggling to think of a single reason to stick with the mechanical pump. It's not even cheaper.

Perhaps Mitch is right. Perhaps a cult drugged me, kidnapped me, and did horrible things to me with mechanical fuel pumps. But since I have no recollection of this, I'm going to go with the clear superiority of a decent rotary pump as my explanation for my distaste for dorking around with stacking shims and gaskets to "dial in" the mechanical pump's fuel pressure, etc.

Glenn Ring is the only guy I've ever heard of liking them, but as Al B pointed out-- Glenn's running (modified) IDFs with GIANT fuel bowls.

Stan, I don't doubt for a minute the fundamental superiority of the rotary electric fuel pump. And I'm sure you are...

It's just that my wise and grizzled mechanic suggested we start with the basic, stock fuel pump when we put in a new engine, just to keep things simple, and to see how that worked out. The plan was to switch to electric if there were any need to. But two years later, there hasn't been any need to.

At least any actual, physical need to - like ominous pools of volatile liquid under the car, an engine that coughs and sputters, or suspicious petrol smells in the garage. I think you've already outlined in detail the theoretical needs to. And I must admit that the Luddite in me is drawn to the prospect of having yet another toggle switch under the dash to command.

"Perhaps a cult drugged me, kidnapped me, and did horrible things to me with mechanical fuel pumps."

I'm heartened to see that our sessions here have helped you to confront the mechanical fuel pump demons in your past. You're still not ready to admit that this actually happened, but this is a good start. I'm sure that surviving the ordeal has made you a stronger person.

"Hey honey, lets just hang out beside the road in the middle of this corn-field for an hour or so while the fuel quits boiling in the line".

You say that like it's a bad thing. I have at least a few memories from my youth when hanging out in the middle of a cornfield with the right someone for an hour or so was not at all an unpleasant experience.

Okay, I think our hour is up now. Let's pick this up where we left off, next week.

Cornfield? I once had a sailboat I kept on Folsom Lake that had a difficult motor to start after the Lake was becalmed around 10PM. 

" I have at least a few memories from my youth when hanging out in the middle of a cornfield with the right someone for an hour or so was not at all an unpleasant experience."

And that back seat in a Beetle sedan was THE best place to be, once you pushed the passenger seat all the way to the front and flopped the seatback forward.

Or, so I've heard 

If my 2 type II's could talk...

Gordon that maneuver you are referring to still required a bit of a contortionist maneuver to execute properly and was not really conducive for extended periods of usage.  I never had a bus whilst young and crazy. I did buy a old Type 2 Westy in 1998' and spent about 7 years doing a restoration. I bought it from a Surfer Dude that was living in it on the beach in LA with two young Surfer girls. I had a lot of fun cleaning out the evidentiary debris that was left behind. However, I could only fantasize about what may have taken place prior to my purchase.