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Filling dry carburetor bowl

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BigBrother-84

Filling dry carburetor bowl

Gentlemen, I am on the route to solve my problem.

Recap.:
- I use my truck (Big Brother) one or two times a month. A little more in summer time, but not so much.
- The engine (351W) is equipped with a 4V Holley and a mechanical fuel pump (which I don't want to modify).
- Carburetor tends to dry between each use.
- Until now, was cranking the engine and "pumping" furiously the pedal until getting a start.
- Jim mentioned he uses a syringe to pre-fill his carb, through the primary vent tube.
- I feel that pre-filling my carb after a long-term inactivity would result in a "softer" and les "agressive" starting process for various parts (battery, starter, etc).

So, I am willing to give a try for this starting method.
I am wondering about your various experiences about filling a dry carburetor.
- How do you proceed?
- How much fuel do you fill?

For the moment, I plan to use a squeeze bottle or a syringe to pour some fresh fuel into the primary bowl vent hole.
Thanks for sharing your advices!

Jeff / 1984 F350 Crew Cab 4x4/5.8L w351 4V/ T18/ D50 4.10 front/ 8' bed.
Restored 2019-2022.
Nicknamed «Big Brother 1984», due to its soooo-looong shape & nod to George Orwell's 1984 famous novel.

mat in tn

Re: Filling dry carburetor bowl

be careful as some paint is damaged by gasoline. don't spill on painted parts and silver seems to be worse than others. I know gasoline evaporates quickly and sitting on a hot engine will speed this up. try to just start it more often. just how vented is the carb that is on it? if it is an original, are the bowl evaporative vents open? these are the large ones meant to keep evaporative emissions from drying off to the atmosphere, part of the vapor recapture system. the two inside the air cleaner housing are much smaller and the ones on holleys "truck" carbs are hooped front to rear with even smaller vent holes to avoid spilling in odd angle driving. this has often made me think the vents are far bigger than needed for most situations.

grumpin

Re: Filling dry carburetor bowl

In reply to this post by BigBrother-84

Another option is starting fluid.

It will get the engine to stumble a bit and easier on the starter.

Dane
1986 F250HD SC XLT Lariat 4x4 460 C6-Sold
1992 Bronco XLT 4x4 351W E4OD
1998 GMC Sierra SLE K1500 350 4L60E
Arizona

Gary Lewis

Re: Filling dry carburetor bowl

Administrator

I believe your mechanical pump will pull fuel through an electric pump. So you could put an electric pump in the line and wire it up to a pushbutton in the cab that is powered by the Run circuit. Turn the key to Run, push the button for a couple of seconds, and then turn the key to Start and it'll fire right up.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

86 1/2 Brutus

Re: Filling dry carburetor bowl

The best and easiest way to do this is how i do it. If the bowls are dry, disconnect the coil to distributor wire, crank the engine for about 30 to 45 seconds, the bowls will fill.

Nick and George
1986 1/2 F150 XLT Lariat 4X2 300 Six - C6 - 3:08 in a 8.8 - Fully Loaded - 8 Foot Box
Owned since new

BigBrother-84

Re: Filling dry carburetor bowl

86 1/2 Brutus wrote

The best and easiest way to do this is how i do it. If the bowls are dry, disconnect the coil to distributor wire, crank the engine for about 30 to 45 seconds, the bowls will fill.

I like this approach, simple and easy. I'll give a try.

My main issue is in winter time, when weather is very cold (let's say below 5°F, often below -5°F).
Batteries suffer of that, one minute cranking can low them drastically.
Have similar issue with my AVTs, as if mixture can't be enough rich for too cold air. They just don't start before the battery dies.

Summer time is different, I can crank longer and let the fuel come up, no battery issue.

That's why I am looking for an easy method to manually fill the bowls before putting battery and starter at work.
Gary's suggestion about a parallel fuel circuit with a small electrical fuel pump could do the job.
But little more complicated to install than a syringe.

I'll consider that, but not this winter.

Block heater (and battery heater pad) help a lot. But the wait for the first spark is still long.

Guys, please don't suggest me to insulate and heat my garage.

I found it was strategic about the rust (and more economic I admit) to keep Big Bro out of the snow/rain/sun way and at "natural" weather temperatures.
The guy has absolutely no rust and I want to keep it that way.

Jeff / 1984 F350 Crew Cab 4x4/5.8L w351 4V/ T18/ D50 4.10 front/ 8' bed.
Restored 2019-2022.
Nicknamed «Big Brother 1984», due to its soooo-looong shape & nod to George Orwell's 1984 famous novel.

mat in tn

Re: Filling dry carburetor bowl

I'm impressed at the concept about natural temps. it is a real thing! my current garage is well insulated, and I use a tiny space heater as a hand warmer basically. everything is cool if not cold. I dress as if I'm outside yet without wind or rain. zero condensation or moisture related issues at all. my last shop was the same way and it allowed me to strip/ sand body panels to the bare metal and be left for periods of time if I got pulled away by other work. sometimes for way longer than preferred.

Gary Lewis

Re: Filling dry carburetor bowl

Administrator

I would not want to crank my engine even close to 30 seconds. In fact the owner's manual says:

Avoid excessive cranking (in excess of 30 seconds) with an intermittently firing or flooded engine. To avoid starter overheat or damage, do not crank the starter continuously for more than 30 seconds at a time. If the engine fails to start within the period mentioned above, wait 2 minutes before again attempting to start the vehicle.

Not only does that hurt the starter, but in really cold weather it will deplete the battery. So I'd either add fuel via the syringe or add the electric pump.

Gary, AKA "Gary fellow": Profile

81-F150-Explorer

Re: Filling dry carburetor bowl

Using a fuel stabilizer/Fuel Antifreeze also helps with cold starting. Back when our trucks were new, they would add Fuel Antifreeze etc, to the fuel. This is something they do not do any longer. I notice a big difference when I use it, than when I don't.

Truck: 1981 F-150 Explorer / Engine: 300-6 California MCU Feedback System / Trans: T-18 - 4 speed / 2.75 Ford Rear Axle Open Diff.

dionden

Re: Filling dry carburetor bowl

If the fuel bowls are dry, then the carb is perculating the fuel when engine is shut off. The carb is not tuned right, the idle speed screw is not set up right, or the secondary plates are drawing in the fuel.
Before going any further with anything, install a translucent fuel filter just before the carb, Is it draining or fuel leaking from somewhere?
My mechanical fuel filter as I just found in cold weather leaks! The fuel filter was dry, but the fuel bowls had enough fuel to start the engine right away.
If it doesn't start right away, there may some thing wrong with the choke. Choke adjustment!

1981 F150 4x2 C6 Flareside 302
1986 F150 4x2 Flareside T170RTS 302 Efi

dionden

Re: Filling dry carburetor bowl

Typo "My mechanical fuel filter = My mechanical fuel pump"

1981 F150 4x2 C6 Flareside 302
1986 F150 4x2 Flareside T170RTS 302 Efi

BigBrother-84

Re: Filling dry carburetor bowl

Interesting, the idea of a translucent filter before the carb, to monitor if the line is full/empty/leaking.

I'll give a try, easy to install. And I'll watch the mechanical fuel pump, we never know.

Jeff / 1984 F350 Crew Cab 4x4/5.8L w351 4V/ T18/ D50 4.10 front/ 8' bed.
Restored 2019-2022.
Nicknamed «Big Brother 1984», due to its soooo-looong shape & nod to George Orwell's 1984 famous novel.

ArdWrknTrk

Re: Filling dry carburetor bowl

Administrator

In reply to this post by 81-F150-Explorer

81-F150-Explorer wrote

Using a fuel stabilizer/Fuel Antifreeze also helps with cold starting. Back when our trucks were new, they would add Fuel Antifreeze etc, to the fuel. This is something they do not do any longer. I notice a big difference when I use it, than when I don't.

You might Ralph, but adding alcohol to gasoline back then would keep water from freezing in the fuel line or pickup at the bottom of the tank where it sits.

Today most fuel sold in America is already 10% ethanol.
If you add a pint (1/8 gallon) to a 19 gallon fill up it's 1/152 or 0.657%

Think about that....

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: Filling dry carburetor bowl

Administrator

In reply to this post by dionden

dionden wrote

If the fuel bowls are dry, then the carb is perculating the fuel when engine is shut off.

If it doesn't start right away, there may some thing wrong with the choke. Choke adjustment!

This isn't about fuel boil or choke settings.
The truck starts just fine an hour (or a day) later.

The float bowls evaporate completely when left all week. (ask me how I know!)
The idea of an inline booster pump with momentary switch intrigues me.
I doubt I'll implement it, but it is appealing.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ckuske

Re: Filling dry carburetor bowl

Administrator

Jim,

I had the same idea, and I implemented it. I tried to choose an electric pump that allowed pull-through from my mechanical pump, I had a push button switch wired, a filter installed between the tank and the electric pump, etc.

It turned out that it seemed to help, but it ended up causing my mechanical pump to fail. There could be lots of reasons for this, so I'm not blaming the electric pump, but is something to be aware of if you start on making that change.

Since I got a new mechanical pump installed and my carb rebuilt, my truck starts very quickly even after sitting for a week.

Just an FYI.

Chris

'84 F-150 XL 2WD Flareside, 302 w/ AOD transmission, Motorcraft 2150 feedback carb w/ CA Emissions, EEC-IV w/TFI, factory A/C, speed control - Info about me and my truck - My project thread

Les Kerf

Re: Filling dry carburetor bowl

In reply to this post by BigBrother-84

My 74 F-350 w/300-6 engine gets used a whole bunch at times, then might sit for months. It would NEVER crank long enough to pump the fuel up to the carburetor. I would have to pull the fuel line off at the pump inlet, then blow back through the tank, when I hear it bubble I would stop blowing, and right away the fuel would be there so I would quickly stuff the line back on the pump, crawl out of the engine bay and crank the engine; it always started quickly after that procedure.

For some odd reason I could never convince my wife to crawl into the engine bay to start the truck, so I finally installed an inline electric fuel pump, which solved the problem quite nicely. It only has to crank a few seconds now to get running.

I wired the pump to only activate during cranking. I contemplated wiring in a momentary button to pre-charge the carburetor, but I feel there is some benefit in having the engine spin the oil pump a few revolutions before the engine fires up after it has been sitting for an extended period of time.

BigBrother-84

Re: Filling dry carburetor bowl

Gentlemen, TADAAAAM!

Big Brother suffers of dry carb bowl syndrome, it's a fact!

He was parked since last January 31th. Six long winter weeks, no block heater plugged, only battery maintenance charger.

Usually, the engine would have cranked a lot before start. Mechanical fuel pump has to work a bit before the carb bowl fills up.

This morning, I tried the "syringe method" to pour some fuel in the carb vent tube.

Success! Big Bro started immediately!

Here a YouTube video.

Jeff / 1984 F350 Crew Cab 4x4/5.8L w351 4V/ T18/ D50 4.10 front/ 8' bed.
Restored 2019-2022.
Nicknamed «Big Brother 1984», due to its soooo-looong shape & nod to George Orwell's 1984 famous novel.

Gary Lewis

Re: Filling dry carburetor bowl

Administrator

Well done, Jeff! So is that the long-term answer to his DCBS?

Gary, AKA "Gary fellow": Profile

BigBrother-84

Re: Filling dry carburetor bowl

Ok Gary, I abdicate.

The Peter Principle won, I just hit my English level of respective incompetence...

And Google does nothing to help.

Please fix my lack of knowledge, what DCBS stands for?

Jeff / 1984 F350 Crew Cab 4x4/5.8L w351 4V/ T18/ D50 4.10 front/ 8' bed.
Restored 2019-2022.
Nicknamed «Big Brother 1984», due to its soooo-looong shape & nod to George Orwell's 1984 famous novel.

Gary Lewis

Re: Filling dry carburetor bowl

Administrator

In reply to this post by BigBrother-84

BigBrother-84 wrote

Big Brother suffers of dry carb bowl syndrome, it's a fact!

Gary, AKA "Gary fellow": Profile