Snorkels on town cars

[joe2006]

I blocked up mine as well a few weeks ago.

Whats the bigger risk, ingestion from the top or the bottom?

I believe that there is a valve that you can install that lets the water out but not in.

 

[Old.Tony]

The small hole shouldn't be blocked. Even submerged, it won't suck water in, but water will eventually drain out.

Air has a certain density. Water is 680 times more dense. When presented with a large aperture (the snorkel head) versus the relatively tiny drain hole, gases and fluids will find the path of least resistance, and if the vacuum created at the airbox's outlet by the turbocharger gets a choice between sucking nice easy-flowing air through a large pipe or relatively dense liquid through a tiny hole, the air will win every time. Not just most of the time, EVERY time.

When the engine stops or the intake suction is taken away so that the pressure above the water is the same as the pressure below the hole, any water lying in the bottom of the airbox will slowly seep out thanks to gravity. Without that, any water that enters your airbox will accumulate and eventually cause problems.

 

[obr1en]

That all makes sense to me. I think i will drill out the silicone.

Thanks for that Tony.

The small hole shouldn't be blocked. Even submerged, it won't suck water in, but water will eventually drain out.

Air has a certain density. Water is 680 times more dense. When presented with a large aperture (the snorkel head) versus the relatively tiny drain hole, gases and fluids will find the path of least resistance, and if the vacuum created at the airbox's outlet by the turbocharger gets a choice between sucking nice easy-flowing air through a large pipe or relatively dense liquid through a tiny hole, the air will win every time. Not just most of the time, EVERY time.

When the engine stops or the intake suction is taken away so that the pressure above the water is the same as the pressure below the hole, any water lying in the bottom of the airbox will slowly seep out thanks to gravity. Without that, any water that enters your airbox will accumulate and eventually cause problems.

 

[gadgets]

Ya mate. Id be re drilling the hole. If water comes in the head of the snorkle it has no where to escape.

 

[BravoBrad]

Leave it open, if you are nervous, drop some 100mph tape over the hole before any DEEP water crossings.

back to the original question.

Personally I have a snorkel just to pissoff people like Bloke48 (insert a big sarcastic smiley face here)

Serious answer here.. I've never had a machine snuff out due to water ingestion from rain. My D40 has the factory snorkel, safari on the 200.

I have a snorkel for 4 reasons.
1) I drive a lot of dirt and like the cleaner air
2) Better fuel consumption (not scientifically proven by me, but I get reasonable consumption)
3) I have heard that in high altitudes, the snorkel helps in low ambient temps (not proven, but I spend a lot of time at low temps up high)
4) If I ever get stuck with flood waters etc, I want to get through, but I don't go looking for water that high

 

[siringo]

Yep, leave the little hole open. Here's my non scientific, 5 second thought process on it...

How many times do you drive in the rain? 100 times a year?
How many (snorkel requiring) river crossings do you do a year? 1?

More chance of ingesting rain water than river water. That's why I left the hole there.

 

[joe2006]

Maybe a job for Mythbusters

Safari recommend blocking all holes: https://www.google.com.au/url?q=htt...oQFjAC&usg=AFQjCNFpLvF1Y02XSrio1TlUdedwDp_N7w

My thinking is a vacuum is created which increases with RPM. This is why a vacuum cleaner picks up solids.

 

[happy john]

If one has a deep crossing over the bonnet a car bra or tarp and a slow steady bow wave the chances of anything getting through that hole are slim.I would be more worried about the cheaper ones not sealing at the joints i spent the extra on the Safari on my last 3 utes despite the ugly ram i have never had an ingestion of water.We got in a horrible storm at Tully coming back from Cairns 300kms of very heavy rain at 90kph i turned the ram around
still had a dry filter.

 

[MjWatt]

I did a lot of research before I brought the safari snorkel - came down to for the extra couple of hundred bucks (if it was even that) and being a little bit uglier, if the one time I need it to work, I want it to work.

 

[bloke48]

See that's, in part, exactly my point. As you can see in the attached photo, those snorkels on semi's dump straight into what looks like a bloody big filter!
http://www.kenworth.com.au/fileadmin/site/brochures/Model_Range/T909_web.pdf

 

[bloke48]

Let's try that again..... right click on the small image icon and then click on "Open image in new tab". Photo pops up as a new tab at the top of the page.

 

[Old.Tony]

Bloke, that image is actually a PDF. I've changed the tags in your post so that people can grab it and take a squiz.

 

[joe2006]

These snorkels sure glamorise the trucks and are clearly town cars.

It would be a bit hard steering if water is expected to be over the roof!

 

[bods]

I also think they may have some problems with water in the engine bay hahahahaha

 

[bloke48]

Thanks Old Tony from an Old Bloke! I think some of the recent comments miss the point. If these snorkels are OK on semis, how come they have what looks like a bloody great filter cannister on the bottom of them? 4WD snorkels sure don't.

 

[Old.Tony]

Trucks have big engines. Your 2.5L engine revving at 2,000rpm (optimum cruise speed for a D40) should gulp 60 * 0.5 * 2000 * 2.488 = 149,280 litres of air per hour. Now apply that to a truck (Western Star 4900FXT with Detroit Diesel 560HP as an example) with a 14.8L engine and every hour (cruise is about 1700rpm) it's guzzling 60 * 0.5 * 1700 * 14.8 = 754,800 litres of air.

Unlike petrol engines, diesels take a full gulp every time the valves open. Mind you, that's the volume at atmospheric pressure too - it will use more if it's boosting.

Any wonder why we have such a small filter in ours - with that much air flow, it would pay to be even larger!

 

[bods]

As above, their great big canisters are where the air filters are housed. Freightliner use a similar system to ours, the air intakes are on the sides of the bonnet, which feed into an airbox that is mounted on top of the motor. Although they aren't as high as some other trucks, they are still as high as a navara with a snorkel fitted... If you actually look at the diameter of the snorkels on the trucks, you'll see they are closer to 5 or 6" in diameter, compared to about 4" on the navara snorkels.....