Water Fording (in numbers)

[MiddleAgeSubie]

We have a pretty good thread about water crossings in general:
https://www.offroadsubarus.com/showthread.php?t=4845&highlight=fording

But I like numbers. This thread is thus about numbers, not water flow rates or how to dodge white sharks while driving from Sydney to San Francisco.

We all know that Subaru recommends water no deeper than the undercarriage.

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.

2/How deep you go without much concern? Either depth or a recognizable point on car.

3/How deep you would go with some extra prep (covering the front, stopping fans, etc).

4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.

5/Any surprising mishaps that should not have happened but did?

 

[MiddleAgeSubie]

I will start but there is nothing interesting here:

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.

Stock 2013 H6 OB except 0.5" spacers and 28.5 vs 27.5 tires (nominal numbers). Total actual lift is about 20mm over stock. Less than an inch for sure.

2/How deep you go without much concern? Either depth or a recognizable point on car.

Luckily, all the water I have had to cross has been 6-12" deep. I consider up to the rocker panel to be my "standard" zone.

3/How deep you would go with some extra prep (covering the front, stopping fans, etc).

Haven't had to consider this question seriously. The one time I was maybe up to 15" was just a spot on a foot deep crossing. Deep water in the US Southwest is rare and seasonal and thus usually easy to avoid on almost every trail.

4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.

On paper, I have thought up to 18" without drama, 2' at most but, again, have not had a reason to give this issue much thought. However, there are a couple of trails I might at some point do that require doing so.

5/Any surprising mishaps that should not have happened but did?

Well, yeah, car shut off after a prolonged drive in water when I still freaked out about a scratch more than two years ago. Restarted. No issue was found. Then same story after a watery/muddy forest trail. I was told that the culprit was poorly installed transmission harness at the factory. Since then no extensive use in water but the car did fine on the crossing where water was briefly over a foot and in up to a foot on other occasions. While this issue never cost me a dollar, it did ruin a day on one occasion and two on the other and it thus prevented me from driving some really nice trails because I was not sure what was going on.

 

[Tweaksta]

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.

2 inch lift. 30cm clearance at most points underneath. No snorkel but a water crossing veteran.


2/How deep you go without much concern? Either depth or a recognizable point on car.

Just got back from outback queensland during a recent deluge, there were many flooded rivers. Have had brief waves come over the bonnet at various times. Comfortable with 50-60cm for extended periods.


3/How deep you would go with some extra prep (covering the front, stopping fans, etc).

Easily does 50cm, 70cm with care and has survived short bursts of 80cm which is probably about the point that water comes over the bonnet, any deeper and I would panic. I have never used front covers or stopping fans.


4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.

If my car had a tarp over the front and fans off, 65-70cm could be done for sustained periods with safe short dips to 80cm but not for too long as the air intake is pretty damn close to that height and it's an expensive risk. A snorkel would be essential for an extended 80cm or more run.


5/Any surprising mishaps that should not have happened but did?

A few members here will remember my trip to the Flinders Ranges where some rain flooded some parts of the Oodnadatta track. Video here https://www.youtube.com/watch?feature=player_embedded&v=ug2gfs6PQ5A. I think I was pretty lucky to survive that without a snorkel. Just a few weeks ago in the Simpson desert we hit a hidden deep spot during a long water crossing and had a wave over the bonnet again. I'll post that video soon, and I also have a few more pics and vids I'll be posting in a report about that trip.

 

[NachaLuva]

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.
Almost 15" to the sills

2/How deep you go without much concern? Either depth or a recognizable point on car.
Anything over the sills will let water into the cabin if you stop. Trick is to use slow steady momentum

3/How deep you would go with some extra prep (covering the front, stopping fans, etc).
I wouldn't go above the bottom of the headlights without a snorkel. You should always stop before entering water, cycle the fans on (hit the A/c) then off, then proceed

4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.
I've been up just over the bonnet. At this height, the rear floats (even loaded) & the front bobs up & down

5/Any surprising mishaps that should not have happened but did?
Haha, a few :lol:

 

[Kevin]

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.

Front to Hub 480mm (19"); Rear to Hub 490mm (19.3"). 270mm (10.6") under the front and 305mm (12") under the rear diff. Snorkel and off switch for radiator fans. Strut blocks and custom struts:
https://www.offroadsubarus.com/showthread.php?t=953&highlight=setup

2/How deep you go without much concern? Either depth or a recognizable point on car.

Over the hood/bonnet for short periods is OK: [ame="https://www.youtube.com/watch?v=fcbpJL0yfm4"]Subaru Forester goes snorkeling! - YouTube[/ame]

3/How deep you would go with some extra prep (covering the front, stopping fans, etc).

As per 2.


4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.

Depending on conditions, tarped up and with reasonable weight to stop it floating 80-100cm (3 feet approx.).


5/Any surprising mishaps that should not have happened but did?

Before I had the snorkel I hydrolocked on a trip to Stockton Beach; car ran for 2 weeks before punching holes through the block!

 

[Rally]

More important than depth is the speed of the water.

 

[Beachworm]

I'm new to water crossings in my Forester. I've done more than one deep crossing in a series 2 Land Rover but that's a different story.

1/Tell us about the ground clearance of your car: what lift, if any. Of course, tell us if your car has been specifically modified to cope with water.


My ground clearance under the front is stock Forester. I have 12mm extra from bigger tyres but lost that by fitting a sump guard. Under the diff is 12mm more than stock.

2/How deep you go without much concern? Either depth or a recognizable point on car.

I would, and have crossed fast running water in the Condamine River at sill height but only after watching a number of other vehicles make the crossing without issue.

3/How deep you would go with some extra prep (covering the front, stopping fans, etc).

I am more confident to cross non-flowing deeper water (up to knee deep - about 450mm) after watching Dedman on video swim his Forester with nothing more than a snorkel added. I purchased a military ground sheet that is ideal as a crossing cover. I haven't used it yet. Yesterday I pulled the air box out and discovered that I have a 4 or 5 litre catch container under the air box so I can swallow up to that amount through the fresh air intake without any getting into the engine. The crossing cover should keep almost all of it out up to the 450mm level.

4/What is the deepest you would do after the best prep you can do? This assumes your other options are dismal enough to make the risk worth taking.

If there was no way around it and I couldn't go back I would be prepared to risk up to 600mm without a snorkel. Any higher than that and I would rather wait for it to go down. If the water was still rising and not fast flowing and it was apparent It would rise 600mm higher than any ground I could park on I would cover the front, spray the electricals with WD 40, wind the window down, take my seat belt off, put my insurance policy in a ziplock bag and give it a shot.

5/Any surprising mishaps that should not have happened but did?

None yet. My email name "safetydave" may give an indication why not. My most recent occupation was a safety consultant. I studied risk management at Swinburne!

 

[Kevin]

Yesterday I pulled the air box out and discovered that I have a 4 or 5 litre catch container under the air box so I can swallow up to that amount through the fresh air intake without any getting into the engine.

Relying on this is exactly how I hydrolocked my engine many years ago! It depends on the design of the "snorkus" box. The SF Forester intake went down through the fender wall into a box and then back up again - a good design for catching water. The snorkus box on my SG model was in the engine bay and the intake passed across the top of it i.e. not through it then back out again. So with that design and under acceleration any moisture was just drawn across the top of the snorkus and straight into the engine

 

[Beachworm]

Relying on this is exactly how I hydrolocked my engine many years ago! It depends on the design of the "snorkus" box. The SF Forester intake went down through the fender wall into a box and then back up again - a good design for catching water. The snorkus box on my SG model was in the engine bay and the intake passed across the top of it i.e. not through it then back out again. So with that design and under acceleration any moisture was just drawn across the top of the snorkus and straight into the engine

It looks like the SH has a similar design to the SG

I don't think I've attached this image correctly. IF THERE ISN'T AN IMAGE OF AN sh AIR BOX REMOVED FROM THE CAR, PLEASE LET ME KNOW WHAT I HAVE TO DO TO INSERT IT CORRECTLY.

 

[Kevin]

Yep, the image is there.


It's different in design but if the air can travel directly across the intake then the end result would be the same. The intake boxes are really meant to muffle the intake sound rather than protect from water.