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Our project VN Commodore is finally back in the garage and ready for some straightening and painting.

Repairing Dents
In this part I would like to talk about dent repairs. Our Commodore is reasonably straight with only a few ’shopping trolley’ dents that need to be repaired, however the methods used here can also be applied to dents of a reasonable size.

Please note that I am neither a qualified Panel Beater or Spraypainter and my methods may not be ‘technically’ correct but I have been repairing and re-painting cars for more than ten years and these methods are what I have found the best, for me anyway!

Where To Start?
Ok, first things first, we need to find out what we are up against. If you want to do a really good job of straightening and painting your car you need to find each and every dent, mark or scratch that will stand out once the nice glossy top coat goes on.

If you have some panels that have many dents or large dents that may have stretched the metal I suggest you search for a replacement if possible. There are ways of repairing large dents however it is a skill that needs to be developed and is beyond the scope of this DIY guide.

The first thing I suggest is to give the car a thorough wash so it is easier to spot any problem areas. The next step is to inspect each panel, one at a time, first by eye-site and then by running your hand across the panel. My choice is to have the car inside when doing this, however the lighting needs to be good. You also need to position yourself in a way that any small dents are seen. For instance, when looking at the doors, crouch down beside the car and when doing flat panels your line of sight should be along the same lines of the panels.

Going over the car twice even three times is a good idea so you don’t miss anything.

Once All The Dents Are Found
There may be some areas where there is a collection of small dents close together that you would like to repair, such as along doors and quarter panels and we will look at what I think is the best way to handle these in Part Four (coming soon, real soon!).

Next we have to figure out the best way to repair each dent. The ideal way is to ‘panel beat’ the dents out from the inside and finish them off with a smear of body filler. This is not always possible and for the most part the type of dents that the garage handyman (person?) would be repairing body filler should be a suitable solution. I don’t suggest using copious amounts of body filler to fill large dents though as it will crack if used too thick and large areas of body filler are hard to get straight and usually look pretty ordinary. If you can get behind the dent and use a hammer and dolly to get the majority of it out that is a bonus and obviously reduces the amount of filler used.

Repairing The Dents Using Body Filler
The first step in the dent repair process is to remove the paint in and around the dent area. For the small dent in the pictures I used 80 grit sandpaper by hand, however any sanding method will do as long as it doesn’t gouge into the metal.

Time to mix the body filler. I have used a Corolla rear quarter window for years to mix the filler on. Pretty high tech I know, but I have found it to be the easiest thing to clean and you can easily mix up some filler and take it with you as you go around the car. Also I have become very attached to a certain paint scraper. I find it heaps easier than the usual plastic things they give you to apply the filler and as you can see it is nice and flexible to follow the panel lines.

Most body filler is mixed at 50 to 1. A little trick a panel beater told me was to think of the filler as a box of matches and the hardener as a match. Two matchboxes of filler, two matches etc etc . Once thoroughly mixed it should be an almost-pale pink colour. A redish colour indicated too much hardener and it will probably harden before you get to apply it, a very-pale pink indicates not enough hardner and you will be waiting forever for it to harden. Getting a good consistency and knowing how much to mix for each dent takes practice but it will become easier as you go. When mixing the filler be sure to ‘force’ the two parts together to ensure that it is thoroughly mixed and any air bubbles are removed.

The way I apply the filler, once again this is only what I find best, is to first apply the bulk of the filler to the dented area and then smooth it out following the contours of the panel. Once the filler is distributed around the area I then go along and smooth it all down. Applying firm pressure to the spatula or paint scraper usually gets the best results. Be sure to extend the filler further than the edge of the dent so you can feather the edge. On a small dent I suggest taking the filler about 30-40mm out around the actual dent area and for larger, deeper dents you can double or even triple this.

Once the filler starts to harden(5-10mins), even if you haven’t finished smoothing it down I suggest leaving it and applying a thin layer of a freshly mixed batch. Sometimes it will ‘ball’ up and ruin the whole surface if you try and smooth it when it has started going hard. If the dent is reasonably deep, ie more than 15-20mm I think it is better to build up the filler with a few applications rather than trying to fill it all in one go.

Once The Filler Has Set
A handy tip I picked up is to run a razor blade across the surface of the filler before sanding. There is usually a layer of wax type material on the top of the filler that clogs the sandpaper in no time and the razor blade removes this and any ridges in the filler and saves your sandpaper.

The only tool I use for sanding body filler is pictured below (with broken handle and all!). There is a name for this tool, it just escapes me at the moment! Speed File, yeah that’s it. These are brilliant for straightening panels as their long surface area ensures that you are sanding along the same original contours of the panel. Use a sanding block or orbital sander is really hard because they have a tendency to pitch up and down with the surface of the filler and not follow the true lines of the panel. Sure a bit of elbow grease is needed but the results will be so much better. I usually start off with 80 grit paper and once the filler is pretty close to flat I switch to a finer paper and then a final hand sand with 600 wet and dry, used dry.

If you find that you have some low areas, indicated by ‘un-sanded’ areas of filler now is the time to apply some more to those areas.

Once you are satisfied that the repair is up to scratch, pardon the pun, it is time to lightly sand the rest of that panel, being sure to remove any remaining sanding marks and move on to the next section. More to come…

After our somewhat dissapointing test of the Water 4 Gas product we went on a quest to find more information on what can be done to save gas in these times of record-high prices. There are more Water 4 Gas tests to come regarding non-fuel injected engines but I’m certainly not going to hold out any hope of earth-shattering results.

 Obviously leaving the car in the garage more often or replacing it with a more fuel efficient model (or buying a Horse!) will help alleviate the strain on our budget’s but for the majority of us this simply isn’t practical or sustainable. Particularly the horse idea.

 There is a lot of talk around the forums and gas-saving websites about ‘Hypermiling’. Hypermiling is a phrase coined by the ‘inventor’ Wayne Gerdes and is basically a term that refers to a number of driving techniques used to decrease your vehicles fuel consumption. Some of the figures quoted by users of these techniques are very impressive and given that these comments can be found on public forums not just on cheesy sales type pages makes one think there might be some truth to these claims.

 I personally don’t do enough driving in a week, or a month for that matter to give an accurate assesment of these techniques (I’m lucky to cover 20 kilometres in a normal week) and I think to try and change Belinda’s driving habits would require a mamoth effort on my behalf, after all she does know everything there is to know about driving a motor car, just ask her! Oh and I shouldn’t forget a little fact that she uses on a regular basis to assert her driving prowess over myself - she has never had a ticket of any kind whereas unfortunately my driving history is a little more ‘colourful’.

 What we have managed to do though is secure a copy of the “The Ultimate Hypermiling Guide” that you can download for free and try for yourself. This guide has plenty of practical tips and tricks for getting the most out of each fill-up and comes complete with a ‘Mileage Log’ that you can print out and keep in your vehicle. Just enter your name and email address in the form in the left hand sidebar and the guide is yours.

 We would love to hear any feedback that you have about the guide and of course if these Hypermiling techniques were useful in keeping your fuel costs under control and by how much.

Craig 

After writing the last update on our Water4Gas test it occurred to me that to make any modifications of my own would be stepping outside the guidelines that I had set for this test. The aim was to take the information that we bought and apply it in a practical environment and post the results. Nothing more, nothing less.

The reason for this is that these ‘products’ are being marketed in a way that makes the buyer believe that there are no special skills or equipment required to successfully implement them. One example of this taken from the sales page:-

We have water-to-energy converters running in all our vehicles since 2006. YOU CAN, TOO! I’m about to show you a SIMPLE technology you can have right now, called Water4Gas. It’s one of the most PRACTICAL free-energy devices, marked by extraordinary simplicity and effectiveness.

Now, up until we had the mixture control problem that you can read about here I was reasonably comfortable with what we were doing. From the results of our (very basic) mileage test we saw an improvement of just over 9% (9.22% to be exact). Things were looking kind of positive.

After we noticed the car running rich I went back to the information to re-read the methods described for combating this issue. I’ll be honest, I hadn’t paid too much attention to this previously and I didn’t think it would be such a big issue to deal with when the time came.

The problems we are having WILL NOT happen on a diesel or carby-fed engine. I would still like to see the results of using this system on both of these engines. I suspect these engines would see better results than an efi engine. Got a spare diesel or carb engine anyone???

I’ll explain again what I believe is happening with our engine. The exhaust gases have more oxygen in them due to the introduction of the HHO gas and the computer interprets this as a ‘running lean’ condition and attempts to rectify the situation by opening the injectors earlier and for longer, resulting in increased fuel usage.

To turn this situation around we need to tap into the signal travelling from the oxygen sensor or mass air flow meter/manifold absolute pressure sensor to the computer and ‘modify’ the voltage that the computer receives so that it reverts back to it’s normal fuel settings. Sounds easy in theory, right? Sure it can be easily achieved BUT without any means of testing what air/fuel ratio we are running and with potential damage being done by ‘leaning out’ the mixture too far we could easily be doing something detrimental to the engine.

Typically when setting air/fuel mixtures or ‘maps’ on a fuel injected vehicle, such as tuning an aftermarket ecu to a modified engine you rely almost entirely on a stoich meter (air/fuel ratio meter) to get your ratio as close to 14.7/1 as possible and to avoid ‘lean out’ at high rpm. Unfortunately in this case a stoich meter is useless as it will read true exhaust gas levels indicating a constant lean mixture (due to the added oxygen from the HHO gas). In-dash air/fuel ratio meters typically read off the signal from the oxygen sensor so once again useless.

Here is how the author of Water4Gas recommends you ‘tune’ your mixture altering device.

Now for actual tuning on the road.

1. Turn the knob all the way to “rich” (it should be fully counter clockwise if you
   hooked it as shown in the last photos of this chapter). This will be factory
   original.
2. Make sure your water device is operational. Warm up the engine and drive a while before messing with the knob.
3. DO THE NEXT STEP WITH CARE – ON A SIDE ROAD - JUST IN CASE YOUR ENGINE STOPS UNEXPECTEDLY.
4. Now start turning the knob clockwise, the mixture will turn leaner and leaner until the car stalls or bucks as you drive. Back the knob off slightly after the bucking and chugging.
5. Keep the danger of overheating in mind. If your Water4Gas device is non operational temporarily, set the enhancer at or near original factory setting (rich).
6. Another thing I’ve noticed is that set points change from one gas station fuel to another, weather conditions, cold engine, etc. The differences are not large, but if you’re on the edge then the car will buck or vibrate and you’ll need to change the set point a bit. Remember that this is a simple device. There is no point in computerizing it, it will require a whole new programmable ECU which is a very costly thing for most drivers and countries.

NOTE: When this device turns on the “check engine light”, and it WILL do that, you can turn off the light using a ScanGauge-II (1996 cars or newer).

As I said earlier, up until this mixture control problem I was reasonably comfortable with what we were doing, but this!! The Camry is probably worth 3 grand if we’re lucky but I won’t be attempting this little modification that’s for sure.

For this mod to be even remotely safe for your engine depends on a number of variables. Namely:-

1. That the Hydrolyzer is producing enough HHO gas to keep combustion chamber temperatures under control. (If you read some of the comments on previous posts it stands to reason that we are not producing a great amount of gas here and there is no documented testing of the expected volume of these units)
2. That the gas is getting to the engine. Apparently the ‘elbows’ used are prone to blocking up
3. That the driver and I quote “Doesn’t overwork the engine by leaning it too much”. How much is too much? How long is a piece of string?

Even if you are ‘car-savvy’ enough to wire in one of these devices could you be confident that you would be able to tune it to a level that would improve your mileage but not lean the mixture to a potentially dangerous level? Sure in the short term everything might be fine but I have to wonder about the long term effects. Way to many variables and not enough documented testing for my liking and I cannot see someone with a relatively new vehicle going to these lengths.

The only plausible solution that I could come up with is to fit a thermo-couple fitting to one of the spark plugs running back to a dash mounted temp gauge to keep an eye on cylinder head temperatures and use a programmable mixture adjustment device that will control the output over a number of load points OR mapping out the sensor readings across a wide range of engine loads without the gas and then using the same programmable unit to replicate these readings with the gas unit installed.

Neither is something that is easily or cheaply achieved. In my opinion the device that is mentioned in the Water4Gas book would be a difficult install for the vast majority of motorists and it certainly gives new meanings to the words simplicity and effectiveness.

JayCar here in Aus has a diy kit that gives you total control over the air/fuel ratio’s for around $80.00 plus it needs a hand controller (or pc) to set the parameters - another $60.00. The time taken to put these kits together and install and tune the lot - Priceless!

Disappointing but it has been an interesting experiment to do and I have certainly learnt a lot from the process, more from people leaving comments than what is in the books though! I got enough out of it to feel that is was worth the $97.00 that the system costs however I detest the way it is being marketed.

There really needs to be some explaining done as to what is needed to ‘optimize’ the system for efi vehicles, even if the methods they recommend are far from ideal. To answer the question posed in the original post - I won’t go quite as far as saying that the system itself is a scam, I would like to see it installed on a diesel or carby engine before drawing that conclusion but I definitely have to say that the way it is marketed is a complete scam.

I am going to finish this post off with a quote that had me nearly falling off my chair with laughter. It is something that should be straight from the X Files but in reality it comes from the fuel saving report in question. I’ll be expecting a copyright breach notice after this post but this is too good to leave out.

Now the problem shows its ugly face when we discover that the computer – your vehicle’s computer – has been pre-designed to protect the vested interest of those who would like to see you waste fuel like crazy. While pretending to be your friends.

The truth is out there.

Craig