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Prime the carb when the gas has evaporated? What do you guys do?

I was talking about sitting for weeks,not after
Sitting for an hour or so.
 
It appears I've been drive-by red X'ed. View attachment 668602

Hey @forphorty - I don't mind a red "X" but at least be prepared to state why you disagree - or offer alternative ideas.
Cranking RPM is slow . Just cranking on the starter won't provide much splash oil to the cam and lifters. It's better to have the engine start immediately and be slinging oil everywhere. This is the main reason that it's recommended to keep the RPM's above 2500 when breaking in a new cam. Obviously it's much less critical after. As far as ideas: Seems like most of the complaints are from the Carter/Edelbrock guys. Holley style carbs have the acc pump at the bottom of the fuel bowl so if any fuel at all remains in the carb you should be able to get a good squirt or two. My suggestion? Get an electric fuel pump and a Holley carb.
 
Cranking RPM is slow . Just cranking on the starter won't provide much splash oil to the cam and lifters. It's better to have the engine start immediately and be slinging oil everywhere. This is the main reason that it's recommended to keep the RPM's above 2500 when breaking in a new cam. Obviously it's much less critical after. As far as ideas: Seems like most of the complaints are from the Carter/Edelbrock guys. Holley style carbs have the acc pump at the bottom of the fuel bowl so if any fuel at all remains in the carb you should be able to get a good squirt or two. My suggestion? Get an electric fuel pump and a Holley carb.
I appreciate your answer. I've had a bunch of both types of carbs over the decades, like most I'm sure have.
There are well known disadvantages to the Holley design as well, of course, and they're enough for me to shy away from them.
Personal choice there. I wouldn't be adverse to running a nice Holley 750cfm vacsec again in the future, in fact.

As far as slinging oil goes, of course there's going to be oil circulating by the simple turning of the engine, running or not -
obviously not as much as when it's running, but some nonetheless. I don't see any harm in that at all.
I've thought about an electric pump, but find it unnecessary for this purpose because with this Carter repro hemi fuel pump, gas
gets to my carb within 10 seconds of cranking anyways.
The starter gets a good workout, sure, but I run a late-model high torque one off a Dakota V8 application and it takes the work
just fine and even spins the engine over faster than the stock 440 one ever did. If it should prove over time to lay down from the
work, that's no biggie either - it's a "lifetime" unit from the local parts store. Free replacement. :)
To each their own.
I don't see this whole issue as that big a thing.

I AM, however, totally against ethanol mandates for our gas,
simply because it has had a very severe adverse effect on our grocery prices AND the environment- and the fuel itself is inferior
in every way to "straight" gas, too.
It's just another case of do-gooders in DC mandating something for our own good, under the best of intentions I'm sure
(yes that was sarcasm - looking at YOU, ADM, Monsanto and others) where the results were nothing like we were told they would be
and we all pay the price for it.

Finally, as far as this whole red "X" thing goes -
Using such a thing, at least from what I've observed over these years on FBBO, is considered somewhat rude and insulting by some.
It's perfectly fine and perfectly acceptable that we can disagree with each other on this forum without resorting to such and we do
every day.
Me, I have some fun with it as you can see. Some others won't. Word of caution on that as a result.
 
Tak419 is correct, I did an experiment last year when the debate in another thread was going on about fuel evaporation. Here is the experiment post I made. https://www.forbbodiesonly.com/mopa...ars-from-my-carb.137351/page-5#post-910766385

Ethanol fuel is a prime issue with evaporation and no matter the carburetor and insulators, they all will eventually suffer from heat soak and evaporate ethanol even faster. With the exception if you have a high rise that sits outside the engine compartment above the hood line!
I remember your experiment (and that thread) very well. It confirmed what my (dusty) old memories of the volatility of the involved chemicals
would do.
Much like having the experience of having to pull over to the side of the road when gas is pouring out the top of an old Holley
(find something and smack hell out of the fuel bowl to get the needle to unstick!!), we now all pretty much know what's going on with todays'
"disappearing gas". The only question is how we each decide to deal with this known issue.
 
Something I forgot to mention is that I bought a Street Demon 625 with the composite bowl for my wife's car...it sometimes sits a month but usually lights off almost instantly.
I know a lot of people think those are junk but it has been the most problem free carb I have ever had. It was spot on out of the box...and it didn't cost $500+
Very interesting. I'm putting together a truck for my dad and have been looking at carbs and was wondering about those, might have to take another look. So how's the driveability, any hiccups? I love my Holley style carbs but have always like the simplicity of the Carter carbs but had bad luck with the Eddy I bought.
 
I appreciate your answer. I've had a bunch of both types of carbs over the decades, like most I'm sure have.
There are well known disadvantages to the Holley design as well, of course, and they're enough for me to shy away from them.
Personal choice there. I wouldn't be adverse to running a nice Holley 750cfm vacsec again in the future, in fact.

As far as slinging oil goes, of course there's going to be oil circulating by the simple turning of the engine, running or not -
obviously not as much as when it's running, but some nonetheless. I don't see any harm in that at all.
I've thought about an electric pump, but find it unnecessary for this purpose because with this Carter repro hemi fuel pump, gas
gets to my carb within 10 seconds of cranking anyways.
The starter gets a good workout, sure, but I run a late-model high torque one off a Dakota V8 application and it takes the work
just fine and even spins the engine over faster than the stock 440 one ever did. If it should prove over time to lay down from the
work, that's no biggie either - it's a "lifetime" unit from the local parts store. Free replacement. :)
To each their own.
I don't see this whole issue as that big a thing.

I AM, however, totally against ethanol mandates for our gas,
simply because it has had a very severe adverse effect on our grocery prices AND the environment- and the fuel itself is inferior
in every way to "straight" gas, too.
It's just another case of do-gooders in DC mandating something for our own good, under the best of intentions I'm sure
(yes that was sarcasm - looking at YOU, ADM, Monsanto and others) where the results were nothing like we were told they would be
and we all pay the price for it.

Finally, as far as this whole red "X" thing goes -
Using such a thing, at least from what I've observed over these years on FBBO, is considered somewhat rude and insulting by some.
It's perfectly fine and perfectly acceptable that we can disagree with each other on this forum without resorting to such and we do
every day.
Me, I have some fun with it as you can see. Some others won't. Word of caution on that as a result.
Bingo, bingo, bingo:thumbsup:
 
Hmmm, take the lid off to fill it with a squirt bottle, an electric fuel pump, or deal with it?

How much are electric fuel pumps, again?
I have the same issue with my car. This Edelbrock carburetor fuel pump and wiring kit solved the issue right and quick.
$210 for the pump. No regulator needed.
https://www.summitracing.com/parts/edl-1791/overview/
This is Edelbrock’s wiring kit.
https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=EDL-1795
Summits wiring kit, cheaper.
https://www.summitracing.com/parts/sum-890023/overview/

Don’t forget fuel fittings!
 
Very interesting. I'm putting together a truck for my dad and have been looking at carbs and was wondering about those, might have to take another look. So how's the driveability, any hiccups? I love my Holley style carbs but have always like the simplicity of the Carter carbs but had bad luck with the Eddy I bought.

I've had nothing but great things to say about it. I was actually looking at smaller carbs for hers as it's just a 302 and only mods are ignition and headers so I was a little worried about over carbing w/625. But with its smaller primary opening its great for idle and low rpm response. The larger secondary ( I think they call it a goggle valve) is more than adequate when laying into it.
I think they make an 750 version too. Some people call it a reworked T-quad...I like it.
It's simple,
I've always liked Holleys but with today's gas even with the high dollar bowl gaskets, they seem to dry out and leak after a year or so..dont have to worry about that with the Street Demon...Eddys are a pita for me...

street-demon-idle-transfer-configuration.jpg
 
Update: So l last Sunday I cranked up then let it sit until Thursday. To my surprise, the car fire right up without even touching the gas! Well I took it for a drive and the engine ran great. I then let the car sit for an hour and it was hard starting and heat soaked. I let it run for a bit and it was fine. Took it home and parked it for two hours. I cranked it up again to go to my friend's house. No issues starting. Then I got stuck in traffic, ran into a store, and started it again. Little hard start but nothing major. Got stuck in more traffic and it started acting up really bad! I thought a spark plug fell off. Then I looked at the temp gauge. The engine was really hot. So I drove it for a bit and ran fine. Today I moved it out of the garage. Hard starting again! I think heat is main factor I'm dealing with.

I have to admit, this old school stuff is too complex for this IT nerd! I really don't know how the old fellows dealt with it! I really don't. I remember my dad dealing with when I was kid. I'm just done with it. I'm going new school!

I'm looking at getting getting a Holley Sniper EFI kit:
https://www.summitracing.com/parts/sne-550-511k

And this distributor:
https://www.summitracing.com/parts/sne-565-305

And a spacer to work with my intake:
https://www.summitracing.com/parts/hly-17-6

Hopefully this will solve the hard starting, priming the car, backfire at WOT, weird idle, and general unpredictable behavior of the changing weather. I'm way more comfortable working with a laptop.
 
No doubt about it, carburetors are finicky bastards.

As an old guy, I can remember the -10° nights after shift change when every other car in the lot had it's hood up. You just don't see THAT anymore.
 
Electric pump did not help on mine. I too spin it a bit for lube purposes without touching the throttle. Then, 5-8 times to the floor. Normal. We forget what normal was as time goes on. Like halogens and bias tires.
 
I have to admit, this old school stuff is too complex for this IT nerd! I really don't know how the old fellows dealt with it!

We weren't useing ethanol gas back then.

I have access to ethanol free gas and don't have any problems with fuel evaporation. I'm useing dual 600 eddies, pump twice, pull the manual choke, hit the key and it fires.

Now I have been using 103 octane 10% during the summer just to see how it acts. I add the Stabil 360 at each fill up and haven't had any problems with it. I had one instance where I had to crank on her a bit before it fired off. I believe it had set for three weeks. Now that it's close to winter, I'll keep it filled with 92 ethanol free again.

On the real hot days, after being out on the road, I'll pull it into the garage, shut it down and put a fan in front of the car with the hood up to cool it down. Takes about an hour or more.

I'm also using 1/2" wood spacers under my carbs, fuel lines have foil insulation on them and the crossover port in the intake is blocked. Running a 180* Super Stant. Also my coolant is mixed for 10* above 0. The more water the better it cools. Coolant additives like Water Wetter and distilled water during the Summer will really keep them running cool also.
 
We weren't useing ethanol gas back then.

I have access to ethanol free gas and don't have any problems with fuel evaporation. I'm useing dual 600 eddies, pump twice, pull the manual choke, hit the key and it fires.

Now I have been using 103 octane 10% during the summer just to see how it acts. I add the Stabil 360 at each fill up and haven't had any problems with it. I had one instance where I had to crank on her a bit before it fired off. I believe it had set for three weeks. Now that it's close to winter, I'll keep it filled with 92 ethanol free again.

On the real hot days, after being out on the road, I'll pull it into the garage, shut it down and put a fan in front of the car with the hood up to cool it down. Takes about an hour or more.

I'm also using 1/2" wood spacers under my carbs, fuel lines have foil insulation on them and the crossover port in the intake is blocked. Running a 180* Super Stant. Also my coolant is mixed for 10* above 0. The more water the better it cools. Coolant additives like Water Wetter and distilled water during the Summer will really keep them running cool also.

Maybe that's the issue? I can't remember having these hard starting issue when I ran ethanol free.

The 87 octane ethanol free stuff is very easy to come by around here but it makes the engine ping and if I turn down the timing the car feels like a slug.

There was a station that had 90 octane, for $4 a gallon, which was awesome but they lost their roof over the summer. They stop selling the 90 octane stuff when they reopened and converted the pump to diesel. Bastard.

I have been using 92 octane from a Kroger's. Maybe I'll switch back to Costco gas?
 
Maybe that's the issue? I can't remember having these hard starting issue when I ran ethanol free.

The 87 octane ethanol free stuff is very easy to come by around here but it makes the engine ping and if I turn down the timing the car feels like a slug.

There was a station that had 90 octane, for $4 a gallon, which was awesome but they lost their roof over the summer. They stop selling the 90 octane stuff when they reopened and converted the pump to diesel. Bastard.

I have been using 92 octane from a Kroger's. Maybe I'll switch back to Costco gas?

Not enough timing will definitely make an engine run hotter. The Factory settings were for the gasoline of the day. Useing the 10% will require a bit more timing. So you have to experiment with it. I found the average 440 likes 18* with 34* all in. Running lean will cause excessive heat. Read your plugs, they will tell you a lot about you fuel and timing.

Controlling the engine temps are a must also when useing the 10%. I'm useing a aluminum radiator, two rows, one inch tubing, fan shroud, 180* T-stat. Runs 10* hotter with 10% gas. It might see 200* on a 90* day in slow traffic. As soon as I'm moving it's back down to 185* to 190*. Useing E-free it never gets over 190*

Top tier gas is another topic that I have discovered. Apparently there's some real junk out there. Here's an article on it and a list of what stations carry it.

https://clark.com/cars/top-tier-gas-stations-clean-engine-aaa/
 
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Electric pump did not help on mine. I too spin it a bit for lube purposes without touching the throttle. Then, 5-8 times to the floor. Normal. We forget what normal was as time goes on. Like halogens and bias tires.
5-8 times! WOW!
 
Good opportunity to build some oil pressure before putting everything under load. I crank my engine for a good 10 seconds or so before hitting the electric fuel pump if it's been sitting.

I CAN turn on the electric pump and hit the throttle a few times with instant fire-up but why would I do that
 
I have the same evaporation problem with my 413, crossram with 600 Carter Comps. I agree with the more evaporation with the Edelbrock (Carter) than the Holley. I had a 600 Eddy on my 305 Chev in my Sreetrod, I had to prime if it sat for a week or more. Have a 600 Holley now, it starts fine even after a couple months. I think this problem gets worse as the crud builds up in bottom of the fuel bowl. A few hundred evaporations has to leave residue.
 
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I have consistently had that problem with my 70 Roadrunner real V-code correct size (larger) factory 3/8" fuel line 6bbl aluminum intake 440....
After about 7-10 days or more of not starting or running it, it takes about 30 seconds or so of cranking to get the fuel to the spark.
I run NO ETHANOL premium fuel 90+% of the time when I am local or heading to the racetrack, and the times I have to use premium gas with 10% ethanol I ALWAYS add a top quality fuel additive like Marine Sta-Bil 360 or Royal Purple octane boost/fuel stabilizer.
Now I just changed from a stock mech fuel pump to the :lowdown: Carter M6903 mech fuel pump, but right away I did the week of Cruisin the Coast. So now my car has set up without running for a couple of weeks, so I can report back on any improvements in reduction of cranking time if any.
I also eliminated the vapor separator and plugged the return line.
 
Good opportunity to build some oil pressure before putting everything under load. I crank my engine for a good 10 seconds or so before hitting the electric fuel pump if it's been sitting.

I CAN turn on the electric pump and hit the throttle a few times with instant fire-up but why would I do that
Because that's what a motor is supposed to do, fire right up!:rolleyes: I don't get this whole priming the oil pressure before every start up logic, does any of your daily drivers that get 200,000-300,000+ miles on them have a pre start oil priming system... No and they run and run and run. The most vulnerable part of the motor to wear is the cam and lifters.... guess what's getting ran without oil with this logic? Your just taxing your starter, battery and making everyone around think your in dying need of a good tune up IMO. :poke:
 
Because that's what a motor is supposed to do, fire right up!:rolleyes: I don't get this whole priming the oil pressure before every start up logic, does any of your daily drivers that get 200,000-300,000+ miles on them have a pre start oil priming system... No and they run and run and run. The most vulnerable part of the motor to wear is the cam and lifters.... guess what's getting ran without oil with this logic? Your just taxing your starter, battery and making everyone around think your in dying need of a good tune up IMO. :poke:
Maybe some of us run engines that are beyond your daily driver. Maybe some start only once a month or so and maybe some very high valve spring pressures, etc. You think built engines will survive 200-300k miles? Think starters and batteries cost more than $2200 valve-trains?

I had a buddy that would preheat his oil in his pulling truck before he would even fire the engine. I thought this was extreme but then again I was just a kid that didn't know any better.
 
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