Integral Vacuum System to Keep my LC Clean

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I have been pondering this a while, and I started to put some math to it to make sure it makes sense.

Does it have any real application? Maybe.

Let's look at the application first.

I want to clean out my truck, but I'm not in the city and I'm not near my home or electricity because I'm out in a remote area testing the limits of my LC and I have encountered dry granular products all around me. These dry granular products have been mixed with water to create a sticky paste and will frequently attach to my footwear.

When I enter and exit my LC, some of this paste rubs off on the carpet on the floor and areas around my feet as well as those of my passengers.

I want to set up a way to clean out my LC in order to preserve it and to make sure my bride is able to enjoy a clean ride while we enjoy the outdoors.

I want to design a central vacuum system in order to vacuum the dirt out of the carpets and seats of the truck, using nothing but the things we carry with us.

I propose to attach an adapter to the side of the intake filter housing where a hose can be attached.
This hose needs to be about 1-1/2" in diameter and about 20 feet long in order to reach everywhere in the truck.
The intake filter is just like the cyclone part of the vacuum system (think Dyson) and the filter element filters the dust just like your vacuum cleaner.

Let's look at the number to determine if this will work.
Materials like this need to convey with about 4000 FPM in the line and possibly as much as 5000 FPM to achieve a face velocity at the vacuum hose attachment of a minimum of 500 FPM.

1-1/2" hose = 1.7614587 in2 = 0.012271846 ft2
Attachment with 1/2" x 4" wide opening= 2.0in2 = 0.01388889 ft2

4000 ft/m x 0.012271846 ft2 = 49.087 CFM

4.5L Engine uses 4.5L every two rotations (because it's a four-stroke engine).
4.5L = 0.158916 ft3
49.087 ft3/m/0.158916 ft3/2RPM = 308.886 RPM x 2 = 617.77 RPM

So, the 4.5L engine will produce 49 CFM at 617 RPM to achieve 4000 FPM in a 1-1/2" hose.

Since the engine is a positive displacement "blower" and it is capable of -17" hg suction at idle, it will be plenty for this application.

I don't know about anyone else, but we have a couple dead vacuum cleaners around that we could grab hoses and adapters from.

So, anyone have any suggestions on connecting to the intake canister? I would want it to be a quick connect with a shut off valve so it won't allow in water.
It cannot interfere with a snorkel.
It needs to have an impact plate where the materials enter the canister so the conveyed materials don't damage the filter itself and suck all the dirt directly into the engine.
The Tuna Can can be removed after each cleaning in order to dump the heavy stuff sucked up.
It may cause the filter change out to be a little sooner, but if you have the washable element, it's that much better, right?

Probably best if it attaches to the actual intake on the LC, so maybe in the fender?

How many people would be up for a kit for their LC?

A lot of folks like to go to the beach. Sand ends up in the truck.
Sand is about 100 LB/ft3. It needs about 6000 FPM pickup velocity.
So, maybe you'd need a throttle to boost the RPM to 927 and hold it there.

Now, if my truck could have an IVS as well as door mounted fuel bladders, I think my life may be complete.
 
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If you're actually serious (god I hope not) you would be wise to add an expansion chamber with an integrated efficient HEPA filter before the vehicle air filter. It won't even add any mass penalty to the system, as the chamber (say, a 5 gallon bucket) could double as a storage device for all that vacuum hose you need to carry anyway. If your math is correct (which I doubt just based on casual observation and experience with vehicle intake volume and velocity, but I don't care enough to try to prove it) then you could easily overcome any loss in performance by upping the RPM a bit. My truck's idle has been adjusted to run at 1100 RPM minimum just for A/C performance gains, and I boost that to 1500+ for alternator output gains when using a 12v compressor for airing up, not to mention that it runs at 3k+ on the highway for hours, so there's no reason to limit it to your sub-1k range. However, no one in their right mind is going to intentionally introduce fine dust, abrasives, rocks, and/or objects of varying weights, shapes, and damage potential to their substantially expensive engine's intake when you could easily carry a small portable vacuum in less space than you're going to fill with 20-30 feet of vacuum hose. At the risk of sounding judgmental, that's just stupid. It actually makes the bladders seem less sketchy by comparison. Which is probably why you spent the time to pose this silliness. I hope.

Oh, and :flipoff2:
 
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If you're actually serious (god I hope not) you would be wise to add an expansion chamber with an integrated efficient HEPA filter before the vehicle air filter. It won't even add any mass penalty to the system, as the chamber (say, a 5 gallon bucket) could double as a storage device for all that vacuum hose you need to carry anyway. If your math is correct (which I doubt just based on casual observation and experience with vehicle intake volume and velocity, but I don't care enough to try to prove it) then you could easily overcome any loss in performance by upping the RPM a bit. My truck's idle has been adjusted to run at 1100 RPM minimum just for A/C performance gains, and I boost that to 1500+ for alternator output gains when using a 12v compressor for airing up, not to mention that it runs at 3k+ on the highway for hours, so there's no reason to limit it to your sub-1k range. However, no one in their right mind is going to intentionally introduce fine dust, abrasives, rocks, and/or objects of varying weights, shapes, and damage potential to their substantially expensive engine's intake when you could easily carry a small portable vacuum in less space than you're going to fill with 20-30 feet of vacuum hose. At the risk of sounding judgmental, that's just stupid. It actually makes the bladders seem less sketchy by comparison. Which is probably why you spent the time to pose this silliness. I hope.

Oh, and :flipoff2:
I challenge you to double check my math.

I like the idea of a 5 gallon bucket as an extra storage chamber, possibly acting as a high-efficiency addition to the cyclonic action introduced into the intake filter housing.

However, adding a HEPA filter is a good idea. You are correct, you may have to increase the RPM of the engine in order to offset the additional differential pressure restriction added by the HEPA. The HEPA would need to be on the "clean" side of the filter.
 
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Milwaukie battery powered shop vac maybe. I use one with a 8.0 battery and it will suck a golf ball through a garden hose!!
Sounds like a great evening at your house!

 

mudgudgeon

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Do you hate your engine?

Very few commercial vacs remove all dust.

I agree on the Milwaukee vac especially if you already have Milwaukee cordless gear.

I've messed around with cyclonic dust separators for a shop vac a couple of times.
They are about 95% effective of you get the design right, but are bulky.

My LC typically has a humble dust brush stowed beside the driver seat. I periodically sweep the accumulated dust, rocks, gravel etc that hitch hike off a construction site on boots.i also use cheap carpet for mats so they can be dragged out and shaken
 
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Since you'll be in the outdoors, and dust can be returned to dust, why not weld a bung to the exhaust manifold with a valve. Then you can just blow all the dirt out using the exhaust. This will prevent any worry of dust reaching the intake.
As a bonus, the pre-catalytic hydrocarbon vapors will actually provide a chemical "dry cleaning" or solvent cleaning effect to the carpets. the heat will also dry up any water

In terms of your math, you're approaching your constraints wrong. You need enough pressure to lift the sand, not so much the FPM concern. You'll need to calculate the pressure drop as a result of length and friction factors of your flexible tubing.
 
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I propose to attach an adapter to the side of the intake filter housing where a hose can be attached.

Unless you're going to block the main inlet, I'm skeptical that you'll get enough suction to effectively vacuum debris.

It would be so much easier just to carry a portable vacuum, either battery or inverter powered. How much space is all that hose going to take up versus a portable vacuum?
 
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Unless you're going to block the main inlet, I'm skeptical that you'll get enough suction to effectively vacuum debris.

It would be so much easier just to carry a portable vacuum, either battery or inverter powered. How much space is all that hose going to take up versus a portable vacuum?
You have a good point about fully blocking the inlet in order to draw full vacuum.

Point well taken on the space taken by the equipment versus portable vacuum.
 
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Since you'll be in the outdoors, and dust can be returned to dust, why not weld a bung to the exhaust manifold with a valve. Then you can just blow all the dirt out using the exhaust. This will prevent any worry of dust reaching the intake.
As a bonus, the pre-catalytic hydrocarbon vapors will actually provide a chemical "dry cleaning" or solvent cleaning effect to the carpets. the heat will also dry up any water

In terms of your math, you're approaching your constraints wrong. You need enough pressure to lift the sand, not so much the FPM concern. You'll need to calculate the pressure drop as a result of length and friction factors of your flexible tubing.
I have worked pneumatic and dust collection for conveying for 35 years. It is the velocity (FPM) past the particulate that will disturb it and get it into the air stream. This is known as the pickup velocity. This is sometimes as much as 2X of the required conveying velocity (typically around 4000 FPM, depending on bulk density of the material) that keeps the product entrained in the air stream.

Remember, I am approaching this from a vacuum (negative pressure) standpoint, however, your approach of pressure with heated air and hydrocarbons could be more viable if it didn't introduce more safety concerns with having airborne particulate introduced, particularly silica. This violates OSHA and MSHA regulations for airborne contaminants.
 
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If you are set on this, why not install a snorkle and make an adapter for the intake of the snorkle to fit a vacuum hose. You can then just connect the vacuum tube to the snorkle when needed. This avoids multiple inlets.

The other option for blowing dust out of the vehicle would be to use a york OBA compressor and just blow everything out. This gives you air for tires etc and avoids sucking dirt into your engine. If you still want a vacuum to run off the engine, maybe use the OBA to createa a vaccuum using the venturi effect or use the air from the oba to power a fan of a vacuum. Still seems like a battery operated hand held vaccuum cleaner would be easier and more compact.
 
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If you are set on this, why not install a snorkle and make an adapter for the intake of the snorkle to fit a vacuum hose. You can then just connect the vacuum tube to the snorkle when needed. This avoids multiple inlets.

The other option for blowing dust out of the vehicle would be to use a york OBA compressor and just blow everything out. This gives you air for tires etc and avoids sucking dirt into your engine. If you still want a vacuum to run off the engine, maybe use the OBA to createa a vaccuum using the venturi effect or use the air from the oba to power a fan of a vacuum. Still seems like a battery operated hand held vaccuum cleaner would be easier and more compact.
Great thoughts on those! Thank you!
 
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Earlier this year I spent a few weeks in the DV desert - lots of dust in the silt beds.

Used my 12V hard wired compressor (that feeds a tank) to blow dust off things. That silt powder is 'fine' and 'sticky'. You can have much higher PSI as compressed air versus trying to suck - you can only pull around 14psi of vacuum...

I was more interested in blowing the dust out of the vents, off general surfaces and where it 'collected' in the window sills and rear tailgate area. Compressed air (100psi plus) did a good enough job of getting rid of most of the dust/powder - well, enough that I didn't care until back in town.

I have rubber mats that are easy to pull out to dump excess foot traffic 'dirt'. My threshold for dirt/dust is pretty high though, from many oz bush trips over the decades :)

cheers,
george.
 
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I would love having an onboard vacuum cleaner in my 80 series.

This would be me solo winter camping in the back of my rig......

 

DSRTRDR

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you cannot be serious :bang:
 

DSRTRDR

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I think we need @nukegoat to pipe in here . . .
 

mudgudgeon

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I think we need @nukegoat to pipe in here . . .
Vacuuming dust out of carpets is a lost opportunity for additional fuel storage.

Dust laden carpet is 11% more absorbent than clean carpet is.

Just flood the carpet each time you fuel up, then use your on board vacuum cleaner to extract fuel, and empty into the tank and needed

- Nukegoat
 

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