Paul’s esoteric meanderings

Airsprings differ from conventional Leaf or Coils in that their behavior is not linear. This gives a significantly different ride to a conventional spring with great resistance to bottoming out. I wont get into better or worse, but will settle for different.

If you are running PolyAirs or similar helper airbags in your vehicle, it’s probably a reasonable idea to know what effect the pressure you are running has compared to the normal spring.

Attached is a spreadsheet that should help you work it out.

For some reason spring loads are commonly still in lb/inch, hence the combination of imperial and metric.  Read more... (444 words, estimated 1:47 mins reading time)

This thought occurred to me as I was fitting the bash plate last week. This thing in front of me that seems to be working just fine – should not work well at all.

Twin tube shock absorbers don’t work on their side or upside down. The gas in them mixes with the oil and turns it into a foamy mess. This sends the damping rates all over the place, making it unpredictably worse than useless.

Monotube dampers are fine on their side, but not many people run monotube steering dampers. My steering damper didn’t look like a monotube.  Read more... (271 words, estimated 1:05 mins reading time)

http://www.landyspares.co.za/landyspares/files/vehicle_recovery_points.htm

http://www.landyspares.co.za/landyspares/files/snatch_straps.htm

I’ve been tossing round the strength of recovery points and the techniques I see used to recover vehicles. My primary concern has always been a shackle or other piece of heavy hardware staying attached to the strap and hitting one of the vehicles or occupants at x00km/hr. A broken strap may not be fun, but a high speed steel projectile is far more dangerous.

My preference is not to use shackles with snatch straps unless it can’t be avoided. They will nearly always be stronger than the vehicle mount points. This means if the vehicle mount fails (likely from the debates circulating) before the strap at 8000KG, you’ll have 3kg of shackle headed toward you at high speed. You just supplied the projectile needed and you know it’s aimed straight at your vehicle.  Read more... (428 words, 1 image, estimated 1:43 mins reading time)

http://www.pirate4×4.com/tech/billavista/Recovery/

If you own a live axle 100 Series cruiser, it’ll have the 1HZ diesel motor in it. There is also a fair chance of it having the factory alloy bullbar, or one similar.

This model (as opposed to the IFS models) didn’t get a bash plate or and form of protection in front of the radiator. If you look under there you’ll see that it is easy for any stick coming up to jam into the Air Conditioning condenser, and possibly into the radiator as well. If you have seen the 4WD Monthly video of Tasmania and the Prado with a smashed bottom radiator tank you’ll know exactly what I mean.  Read more... (493 words, 2 images, estimated 1:58 mins reading time)

Basically every generator on the market is next to useless for the average four wheel driver. The normal generator puts out 240V. Next to nothing you need when camping runs on 240v, you need 12V. That will run your fridge, flouro lights, water pumps and recharge your batteries.

Here’s the catch. To get 240V down to 12V means a battery charger. Most battery chargers only put out 4 – 8 Amps depending on the model. Expensive versions put out 10 – 16A but will cost $150-$400. Assuming the average person uses approx 40A/H per day, that’s going to take 4 – 8 hours to be replaced.  Read more... (351 words, estimated 1:24 mins reading time)

Now I see the topic of mechanical lockers come up time and again on lists. There are descriptions all over the place of these things, and most are right in their outcome, and wrong in their “why”. So this is the “why”.

This mainly relates to the Lokka and Lock-Rite lockers. Detroit has a similar process, however I have never pulled one apart and I believe there are some differences.

First, Mechanical lockers are NEVER locked. Any document that says they are locked is either over simplifying, or doesn’t have a clue.  Read more... (1152 words, 3 images, estimated 4:36 mins reading time)

It’s only the ARB one that came with the lockers and it takes 127.35 seconds per tyre instead of the 124.28s of the other one. I’m never going to get a girlfriend with that sort of performance.

OK – so it’s not real fast, and I am real lazy. Pumping up tyres, bending, checking pressures, inflating still, checking again etc. It’s all too hard. A faster compressor would help, but I prefer the Shell digital auto inflator thingy – drive up – attach – tyres are set. So simple.  Read more... (288 words, 1 image, estimated 1:09 mins reading time)

Last trip to Sundown I noticed some unusual noises on the way into the park, but couldn’t track is amongst all the other rattles from the crap in the back.

I had the lockers installed 6 months ago when the front diff was broken as it seemed an opportune time. This was my first chance to really test them out in anger, and I planned to have some fun getting into places that were normally too rough or steep to attempt.  Read more... (340 words, estimated 1:22 mins reading time)

Hard numbers on rear suspension travel for my HZJ105.

When reading articles in magazines, I see this statement all the time: “We broke a shock absorber” and then remarkable stories of welding it up with batteries or bubblegum.

Myself on the other hand have never broken a shock absorber. Not in the rally car, not on Cape York corrugations, not playing silly buggers at Ormeo, not whilst breaking diff’s, not whilst launching 4wd’s or race cars airborne, not whilst towing heavy loads, not whilst hot, cold etc etc. I have tried good factory shocks, worn out crap factory shocks, Monroe’s, Koni’s, Bilsteins, Old Man Emu, yet none of them have broken. Get the drift.  Read more... (1361 words, 7 images, estimated 5:27 mins reading time)

Because I got sick of explaining why the diff lock button in your Cruiser / Discovery is not the same as the diff lock buttons in mine…..

http://www.safari4×4.com.au/80scool/george_couyant/diffs/diffs.html

Summary: If you own an AWD car – AWD should stand for Any Wheel Drive – Any wheel with the least traction will get all the drive. The centre diff button just turns it into a “normal” “traditional” 4wd, that is one front and one rear must lose traction to stop going forward. This happens on many hills and is the reason pressing this button doesn’t do that much more to where you can go.  Read more... (109 words, estimated 26 secs reading time)

Road worse than normal, soft roaders would get in but need help to get out.

Plenty of water at Burrows Waterhole – this surprised me. The toilets are getting pretty full, the ranger plans to build new ones.

Red Rock Gorge track in good condition, no problem for soft roaders.

Reedy Creek track in poor condition – similar to Rat’s Castle.

Rat’s Castle road in usual condition. Soft Roaders need not apply. Standard Nissan Pathfinder managed the loop, but be prepared to use plenty of right foot.  Read more... (513 words, 5 images, estimated 2:03 mins reading time)

The batteries in the HZJ105 were cactus. They were the ones it came with and the whole system was dubious and time for an upgrade. When I purchased the car the wiring was a mess, although quite effective. I am still sorting some of it out.

My goals were as follows:

1. Seperate battery for starting
2. Maximum capacity for Aux items
3. 80Ah Useable Capacity
4. Option to expand to triple battery setup for winching

I’ll go into a debate on battery system choices in a seperate article, but to meet my needs I chose the following:  Read more... (764 words, 3 images, estimated 3:03 mins reading time)

http://www.exploroz.com/Forum/ArchiveView.asp?ForumQID=32036

Battery isolators and battery systems are always an area of hot debate. This article is not to get into the differing battery constructions and variants, but rather into the systems to manage them.

In an ideal world every cell would be managed independently, and batteries would cover all our needs. The reality is that we have to make do with  differing solutions and varied information.

Some of the best battery information is here, here and here

This guy also has great information.  Read more... (1248 words, estimated 4:60 mins reading time)

An excellent test of products in the marketplace, all destroyed on a test rig. Love it.

Results surprised me slightly.

http://www.lizardlegs.com.au/blackrat/news.asp

As you can read on many websites and discussion lists, it will bring about the end of the world if you put two batteries that are not exactly the same in parallel.

Unfortunately for most 4WD owners, this is exactly what we want to do. Even if they are exactly the same using an isolator makes them do different jobs, so when you go to charge them they are no longer the same.

95% of battery isolator systems charge your dual batteries in parallel. Even the ones that claim to be smart – are just a set of relays (switches) inside to parallel the batteries together. (There are some EXPENSIVE exceptions, you’ll know already if you have one).  Read more... (201 words, estimated 48 secs reading time)