The alternative to a snorkel

[Chris]

Presumably you'd need to stick some sort filter on the end just to keep the noise down as Adrian says. Could sound rather throaty in there. Certainly have to turn the radio up a bit.
It wouldn't be used for very long I guess. Cruisers are very well sealed and with that volume of air being pulled out of the cab, I bet you won't be able to open the doors
If it's switched over, make sure you leave a window open before getting out and shutting the door or you might have to wait until it runs out of fuel and stops.

Chris

 

[Roger Fairclough]

I cant believe no one has worked out the best use for this device yet; when someone lets rip in the car this will clear it instantly!

Seriously though this is a really good idea, I remember you showing me the prototype a few years ago and I was sorely tempted to make my own then. Im assuming by the looks of where it goes through the firewall in the pictures it enters the cab behind the dash? Keep in mind there is some serious suction when the engine is above 2000rpm so if there is anything near it you could loose it into the filter (my snorkel sucked an 8mm spanner off the roof when I was testing it!). Is it noisy when its open?

It enters the cab just to the off-side of the brake assembly. It will be noisy when in use but this is an indication that the valve has correctly opened. More on this later in the string.

Roger

 

[Roger Fairclough]

That is a great lateral approach and love the logic - fabulous. How about the equivalent of a ballcock in the engine bay that operates the valve once the water has reached a certain level before the air intake?

Now who are the 4 forum members who will make up the Landcruiser Den

I did look at the idea of a 3 way ballcock design for the unit. Problem was the size of the valve with a 75mm bore and the complexity of the actual 3 way system.

Roger

 

[Roger Fairclough]

Frank, just thinking that if you went with en electromagnetic activation, would you include an indicator light to show it had switched? I'd want to be sure before I went wading that the diverter had moved.

Chris

The electro magnet idea was one of a number that came to mind. Another idea was to use a section of the old style wiper motor to wheel box actuator---it's a sort of spiral on a cable---which I could wind in and out. I would prefer a mechanical system as any thing electrical brings it's own problems.

 

[Roger Fairclough]

The standard air box has a rubber flap drain hole at the base. I blanked this off. Also, the plastic gubbins that festoon the outside of the air box have a number of drain holes in them. I have removed all of them and fitted a 75mm i/d pipe straight into the side of the box. Now I have never seen the fitting instructions for a proprietory snorkel but I would hope they tell you to seal or blank these off, otherwise the snorkel itself would be rendered pretty useless with the water that could rush inwards under the pressure of deep wading.

Roger

 

[Chris]

Sorry Roger, just realised I called you Frank. Either way, it's probably a compliment to you both!

Dave.

 

[Roger Fairclough]

The points raised about the flap valve being either fully open or shut and the problems of dirt or vegetation partially blocking the unit are valid. This is one reason I have spent so long on it's design and construction!

The interior condition of the flap valve can be quickly checked by removing the top cover. It's held down by 5 s/steel c/sunk screws, so corrosion will not be a problem. The body and parts are all plated to resist corrosion. The flow of air through the unit should stop any dust from sticking to the internal parts of the valve. When I replace the air filter the amount of dirt in the filter box is very small. Air for the engine is drawn in from inside the inner wing. This area is surprisingly clean, so I don't believe that the ingress of vegetation will be a problem. Also the valve will be actuated before wading begins, so there shouldn't be anything within the valve to jam it.

A few miles from Redditch is a ford that crosses the River Arrow at Coughton. Normally it is benign and a favourite place for the kids to play in during the Summer. The base is concrete, although a bit battered in places. During heavy rains this idyllic spot---it's next door to Coughton Court, of gunpowder treason and plot infamy---can be turned into a raging monster that will devour anything that attempts to cross it. The concrete surface is slippy with mould and the flow of water can quickly throw you off course and seconds later you are jammed under the footbridge that's situated 10 metres down stream. If you have a 4x4 and a snorkel fitted you engine may well be running, but you are still stuck under that bridge and fast filling with dirty water.

Very few rivers are deep and not fast flowing. The valve is for peace of mind during those crossings that are, hopefully, short and quick.

Roger

 

[Roger Fairclough]

Sorry Roger, just realised I called you Frank. Either way, it's probably a compliment to you both!

Dave.

Frank, oh don't worry about him, he's about here somewhere, keeps sticking his oar in at inopportune moments. The doctors keep talking to me about him and every now and again he buts in but I, and all the others, we don't really mind.

Now who am I?

 

[Birder]

Sorry to say that the forward / rearward discussion has been done to death and it's been show to be utter bunkum.

Sorry Chris I dont see how this can be right, simply look at the back of any 4x4, the rear tailgate is always covered in much more crap than the front as the dirt hangs in the turbulence so it must be doing something.

Also to Roger, I agree with you on keeping it mechanical so a simple lever and cable would work to control your flap

 

[SpinDrift]

The points raised about the flap valve being either fully open or shut and the problems of dirt or vegetation partially blocking the unit are valid. This is one reason I have spent so long on it's design and construction!

The interior condition of the flap valve can be quickly checked by removing the top cover. It's held down by 5 s/steel c/sunk screws, so corrosion will not be a problem. The body and parts are all plated to resist corrosion. The flow of air through the unit should stop any dust from sticking to the internal parts of the valve. When I replace the air filter the amount of dirt in the filter box is very small. Air for the engine is drawn in from inside the inner wing. This area is surprisingly clean, so I don't believe that the ingress of vegetation will be a problem. Also the valve will be actuated before wading begins, so there shouldn't be anything within the valve to jam it.

Ok Roger, understood. Just probing the mod. It does look like quite a lot of work has gone into it. As I said earlier, I like the mod and especially if you want a discrete air intake eg if the car is a daily drive that you also use for work etc, you dont have a monstrous pipe sticking out of it.

 

[SpinDrift]

Sorry to say that the forward / rearward discussion has been done to death and it's been show to be utter bunkum.

Sorry Chris I dont see how this can be right, simply look at the back of any 4x4, the rear tailgate is always covered in much more crap than the front as the dirt hangs in the turbulence so it must be doing something.

mmm, I think that to understand the movement of air with a rear facing snorkel you would need to carry out some kind of test using smoke so you could see how the air is flowing.

My snorkel is rear facing and has been years.

off topic ....

 

[Roger Fairclough]

The points raised about the flap valve being either fully open or shut and the problems of dirt or vegetation partially blocking the unit are valid. This is one reason I have spent so long on it's design and construction!

The interior condition of the flap valve can be quickly checked by removing the top cover. It's held down by 5 s/steel c/sunk screws, so corrosion will not be a problem. The body and parts are all plated to resist corrosion. The flow of air through the unit should stop any dust from sticking to the internal parts of the valve. When I replace the air filter the amount of dirt in the filter box is very small. Air for the engine is drawn in from inside the inner wing. This area is surprisingly clean, so I don't believe that the ingress of vegetation will be a problem. Also the valve will be actuated before wading begins, so there shouldn't be anything within the valve to jam it.

Ok Roger, understood. Just probing the mod. It does look like quite a lot of work has gone into it. As I said earlier, I like the mod and especially if you want a discrete air intake eg if the car is a daily drive that you also use for work etc, you dont have a monstrous pipe sticking out of it.

As the rep for Warwickshire for GLASS, I feel that being as unobtrusive as possible when laning is a good idea and less likely to create animosity towards genuine users of our rights of way. Although a 4x4 with stickers covering the rust spots. a dozen or more lamps pointing in all directions, bridging ladders, a snorkel, and every other "must have" accessory might be legal, it's hardly going to give the impression that we care about the countryside. I remember, with a degree of smugness, gently and quietly coming up behind a group of walkers on a Warwickshire lane. I got within 5 metres of the back of the group before they heard me. I think they were as astonished/amused as we were as to how close we got before they new we were there. End result was a wave and a smile as we went past.

Roger

 

[wobbly]

Looks like a top bit of kit Roger.

Pete

 

[Chris]

I don't think that you can compare the forcing of 4 meters square of 4x4 through the air creating a massive hole which closes behind it, with the snorkel head facing backwards.

The point of the rolling road experiment was that it was a dynometer measuring HP, torque etc. These figures didn't show a difference. So regardless of whether it creates low pressure or not, it doesn't make a practical difference. It's drawing in air after all - but facing backwards if low pressure is created by some sort of cavitation, it's unlikely to be sufficient to starve it of air. Plus it would be speed related. I just chalk it up to being an Old Wives' Tale. Does it make the difference between 20 to the gallon and 25? Err no. Then frankly I'm not bothered.

Some people have said that fitting a snorkel has improved mpg for them. Can't say I have ever noticed an increase.

Chris

 

[revs4x4]

Roger...hmmm looks very tempting....what are the costs involved (i.e. how much are you going to sell them for! !!)......

 

[wobbly]

Stop me if what i'm saying is daft,but....

Coulnt you fit one of these in line with the normal air intake, so you could then add an external snorkel - in this way the snorkel is only in use when it is needed, thus removing the complaint that a snorkel makes the engine gasp.

I understand that a snorkel may or may not cause a lack of air if rear facing - but enough people believe it does to create a market for these!

Not just LC's, but landies also, for when they are not broken down.

Pete

 

[Roger Fairclough]

Roger...hmmm looks very tempting....what are the costs involved (i.e. how much are you going to sell them for! !!)......

Material costs are very small, probably about £50 in total, but the labour and fiddling time was huge. As Dave said earlier, Iv'e been working on this for a couple of years.

Roger

 

[Roger Fairclough]

Stop me if what i'm saying is daft,but....

Coulnt you fit one of these in line with the normal air intake, so you could then add an external snorkel - in this way the snorkel is only in use when it is needed, thus removing the complaint that a snorkel makes the engine gasp.

I understand that a snorkel may or may not cause a lack of air if rear facing - but enough people believe it does to create a market for these!

Not just LC's, but landies also, for when they are not broken down.

Pete

It's an interesting thought Pete, but, in my case, I wanted a system that did away entirely with the standard snorkel, although it could be adapted for your idea if someone wanted it that way.

Roger

 

[jonkem]

So you finally got it finished then Roger? You're right, it was probably around 2 years ago that you dropped this idea into my build thread I didn't respond at the time because I couldn't decide if it was a good or bad idea.

To jump on the bandwagon a bit 1st, forward facing snorkels don't tend to have any problems with water ingress in heavy rain and the induction system can cope with quite a bit of water because it is suspended in a large volume of air. Rear facing is thought to be better for fast road use in dusty conditions but in reality the dust is suspended in the air being drawn in whichever way the snorkel faces. The whole question of the best way to draw air in is covered in an excellent book "Race & Rally Car Source Book", it's not as simple as most of us think!!

In response to earlier points raised:
You should try to have the windows open before going into deep water, it's difficult to open a door when it's that deep, so air will be available for the engine and driver.
Induction noise is a small price to pay to ensure the engine keeps running.
If the valve has proved itself in testing then there's no difference regarding risk than having a snorkel. For example, once you've fitted the snorkel and tested it's watertightness, has it subsequently sprung a leak? You'll only know once you've ingested water
The dirt on the back of 4x4s is created by the updraft created by the car passing over the dust not by a downdraft from the roof. Simple to stop it happening by fitting a small roof spoiler as seen on lots of road biased 4x4s. They direct the air downwards from the roof to counteract the updraft.

I'd expect Roger to have designed the valve so the direction of airflow will assist in keeping the flap closed?

A nicely presented 4x4 is always less offensive to walkers than a rough looking one and especially a well and considerately driven one tends not to get them waving sticks

Over-riding all of the discussion though, don't go into deep water unless there isn't an alternative. It's not just dangerous to your engine

 

[Roger Fairclough]

All very true Jon.

I tried driving with the valve in the snorkel position. Think twin 40 DCOE's in an open topped MGA. It actually quietens down once you are cruising. With windows and roof closed, no problem, I assume the various air vents supply sufficient for the engines needs.

I read an article in the magazine of the North American Land-Cruiser Assoc., which details the work necessary to prepare a motor for the various river crossings in Alaska. We are not talking about a quick splash in here, more a lengthy run across a swampy morass around 4ft deep. Think Russian off-road events around Ladoga. Wading through deep water can be ruinous to starters, alternators and such unless extreme measures are taken to waterproof them.

I was thinking of a single piano wire inside a bowden outer cable for the control system, but on reflection, a twin (pull on, pull off) system with normal braided wire will be better and more predictable. If I can find a suitable mounting point, a heater slide control may be ideal.

Roger