None. I'm run them like this in 2 different vehicles. Uses 100% of the fuel and doesn't suck air.
CK5
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Propane consumption?
- Thread starter mason72
- Start date
None. I'm run them like this in 2 different vehicles. Uses 100% of the fuel and doesn't suck air.
From what i have read and seen, the 2 style tanks bbq and fork lift work differently. Your gas grill tank operates and uses the vapor from the tanks, forklift draws liquid. Part of that is why with running forklift you need to use your heater hoses to warm the liquid to convert it to a gaseous state. Running forklift tanks standing up "may" work fine but that could also be why you will only get short bursts of wide open throttle. With the tanks layed down with them on an angle toward the valve(tube) i would't think is needed this way. Standing up tho on an angle for sure....part of the reason on forklifts the tanks always lay down and also why the tanks have the little pin so it sits in the mounts correctly.
With having the single carb and mixer especially impco stuff i think its only good for 450 cfm at most. Big inch or small motors with high compression most of the time will need the 2 carbs and 2 mixers. But with running them with the impco dual carb mount with one base plate they really don't kill the fuel like you would think until you start getting heavy in the rpms. Also what helps a ton with propane is a good distributor that really is all in at 3k rpms. I messed with this alot doubting that theory and came right back to it.
With having the single carb and mixer especially impco stuff i think its only good for 450 cfm at most. Big inch or small motors with high compression most of the time will need the 2 carbs and 2 mixers. But with running them with the impco dual carb mount with one base plate they really don't kill the fuel like you would think until you start getting heavy in the rpms. Also what helps a ton with propane is a good distributor that really is all in at 3k rpms. I messed with this alot doubting that theory and came right back to it.
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I had my tanks mounted vertical for a while before I built my new mount. 2 of my 7 tanks would only use about 60% of the fuel mounted vertical but will use 100% horizontal. My others all used 100% when vertical. I'm not sure if those two tanks have a different style pickup or what the deal was.
And I don't think it's possible to "suck air" as it's a closed pressurized system. As long as there's pressure on the tank you shouldn't get any additional air.
With tanks standing up it would depend how long the draw tube is inside the tank. The longer the tube the more fuel it will pull and the only way to really know with that is taking em to a gas place to have the valves changed. Both my 10 gallon have about an 18 inch tube.
Here is what the inside of a commonly used 7.8 gallon forklift tank looks like. Forklifts use them in the horizontal position because the air bleed/80% full valve needs to be at the highest point while filling and most forklift operators are not real smart and would mess that up often. Plus most propane lifts are standardized and having a tank in the vertical position is not as easy to fill because the tanks are mounted on top of the rear counterweight.
My first tank was a clear composit so I could visually see the liquid, they have been discontinued by the only 2 manufactures. I run my tanks until they are empty and it always takes just under 8 gallons to fill them. It is possible to suck vapor and not liquid if the suction tube is not correct.
All the data I have seen shows the Impco 425 at 460 cfm which should be enough for around 320 hp which is a little over what a stock vortec 454 is rated for (290 hp). The distributor is a new MSD PN 8365 with the lightest silver springs so the timing is 32 degrees at 1800 rpm. The Model E vaporizer is mounted directly to the mixer so no worries about a long vapor hose. I'm hoping to get it on a chassis dyno soon to see what the issue is.
Here are some info links for the common Impco model 425 mixer
https://www.propanecarbs.com/impco/425carburetormixer.html
http://www.rasoenterprises.com/index.php/propane/31-carburetion/65-impco-fuel-mixtures
Here are some info links for the common Impco model 425 mixer
https://www.propanecarbs.com/impco/425carburetormixer.html
http://www.rasoenterprises.com/index.php/propane/31-carburetion/65-impco-fuel-mixtures
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The short or connected right to the carb vapor hose deal is real good. That helps starting and throttle response. I'm not sure if you seen or read about positioning the model e on its side , they stay cleaner and the build up inside doesn't get as bad. That could be here say tho... I do tho like the msd deal tho you posted above, i might have to look into one of those. Although 1800 might be a little early tho for higher hp motors.
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What mixers are those and where do you get those cable pre injector levers?
These are mm x450's, these are older but pretty awesome. Pretty high quality, whenever i see them i buy em..lol. I have 3, real hard to find. One in the picture was brand new at that time. Only a few o rings to rebuild these and very little maintenance. They are a variable venturi style, even have a power valve. These also put out more cfm than the impco's. These carbs alot of places use to sell them, got propane did about 6-7 years ago.
The cable primer i use as a choke to fire it up, it doesn't start easy with the 2 carb setup and the carbs so high. I bought the lever and the cable in a kit from nash fuel(link below, its not cheap). I buy most of my stuff from here. Also if you look at the model e in the front lower bottom by the carb you will also see a cold start valve screwed in to the model e. I'll put that link in too, this one you operate with a toggle. To be honest i'd rather buy the last link i posted before the other 2. The cable lasted about 5 years and is super stiff. Its steel on steel, i had to buy another choke cable from the dorman section to fix it. The enrichment valve works decent but i would need 2. Nah, ill just pull the primer 3-4 times and varoom.
http://nashfuel.ecrater.com/p/21051427/impco-cable-manual-hand-primer?keywords=cold+start
http://nashfuel.ecrater.com/p/18223368/impco-sv-cold-start-assist?keywords=cold+start
Here is also an electric primer instead of the cable
http://nashfuel.ecrater.com/p/18223506/impco-electric-solenoid-cold-start-for?keywords=cold+start
The cable primer i use as a choke to fire it up, it doesn't start easy with the 2 carb setup and the carbs so high. I bought the lever and the cable in a kit from nash fuel(link below, its not cheap). I buy most of my stuff from here. Also if you look at the model e in the front lower bottom by the carb you will also see a cold start valve screwed in to the model e. I'll put that link in too, this one you operate with a toggle. To be honest i'd rather buy the last link i posted before the other 2. The cable lasted about 5 years and is super stiff. Its steel on steel, i had to buy another choke cable from the dorman section to fix it. The enrichment valve works decent but i would need 2. Nah, ill just pull the primer 3-4 times and varoom.
http://nashfuel.ecrater.com/p/21051427/impco-cable-manual-hand-primer?keywords=cold+start
http://nashfuel.ecrater.com/p/18223368/impco-sv-cold-start-assist?keywords=cold+start
Here is also an electric primer instead of the cable
http://nashfuel.ecrater.com/p/18223506/impco-electric-solenoid-cold-start-for?keywords=cold+start
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thx guys..your links just cost me 200 bucks 
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This is perfect timing. lots of great info. I'm getting really close to completing my propane system and firing it up. I'll be saving this thread for future reference. What are the smaller 3/8"? rubber hoses running from your vaporizer to the mixers? Mine doesn't have that, or atleast not yet?
thx rob..your links just cost me 200 bucks
No problem, Better you than me...lol.. This crap adds up but its really nice to go the extra mile and add the little touches.
Do you have an x450..?
If you look at the model e where the 3/8 is there use to be a gold screen in that spot, then look at the carb pic above and you will see that's an open port on the carb. My setup needed that, yours may or may not. My motor has alot of valve over lap so vacuum is not my friend here. The brakes were that bad that i needed a moroso canister. So somethings are hooked up for that benefit.
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FYI, If you Amazon Nashfuel you can get those links alot cheaper and with free shipping if your a prime member
I almost fell off my chair when i seen those prices now, i bought that stuff a few years ago and i know for instance the cable primer was like 30.00. I have another sv start assist with the v8 pill for enrichment that i'll never use somewhere here.
Oh and since we are spending money..lol....here is the low fuel light setup that i have and it works pretty nice.
http://nashfuel.ecrater.com/p/18223444/dash-mount-warning-light-for-propane?keywords=low+fuel
http://nashfuel.ecrater.com/p/18223444/dash-mount-warning-light-for-propane?keywords=low+fuel
No I see, I don't have the 450s. They must be different and need that hose. I bought my kit from Got propane, its a dual set up. So you would suggest the cold start valve and the electric primer both? also would I need them on both vaporizers or just one of them?
Got go to work now. I'll check in later
What i would do is don't buy anything and see how it fires. The impco carbs i'm not familiar with so maybe they will be easier starting. If it turns over too many times and you have an electric lockoff then turn the key on and go out and push the primer button on the model e. Then start it... If that does the trick then just either pick up the electric or cable primer. (Or open the hood each time and push the button....lol..) I only have the cable primer on one and it fires decently, within 5 turns.
Do you have a build here for this..? I'd like to see what all is in the kit cary sold you, he seemed like a good guy when i called. He lost me tho saying he never sold the carbs i have and the guy i got my 1st setup from(used) had the receipt...
Oh are you using dual carbs or dual fuel..? If you look in my pics i have a 14 inch air cleaner that fits 2 carbs that is a custom fit for the impco dual adapter. I just bought the base and used my air cleaner instead of buying it all.
Do you have a build here for this..? I'd like to see what all is in the kit cary sold you, he seemed like a good guy when i called. He lost me tho saying he never sold the carbs i have and the guy i got my 1st setup from(used) had the receipt...
Oh are you using dual carbs or dual fuel..? If you look in my pics i have a 14 inch air cleaner that fits 2 carbs that is a custom fit for the impco dual adapter. I just bought the base and used my air cleaner instead of buying it all.
I have owned 2 kits from Cary over the years. The one I have now I bought complete but used. see my build thread below for pics... works great fires right up..And you need to stop linking stuff..I cant afford it
