Brake noise to some extent is normal, especially on new pads. Most cars are using a harder compound, usually a semi-metallic material. Honda Parts and Toyota Parts are often the most guilty of this. Squeals heard the first few stops in the morning when the brakes are cold, and squeals that are heard the last few feet while coming to a stop are usually nothing to worry about. Constant noise or harsher sounds should be checked out asap. They could be signs of bigger problems.

The most common cited reason for the noise. Semi-metallic brakes are made of bits of metal shavings in place of the banned aspestos material. These semi-metallic brakes have great stopping power and have a long wear life, but can cause a high-pitched squeal that drives car owners crazy and frustrates mechanics who can’t get it to go away to please their customers.

If you have any noise you should inspect your brakes. You are looking for any signs of cracking, inconsistent wear, loose fittings, etc, etc. Constant noise or harsher sounds should be checked out asap. They could be signs of bigger problems.

The do make brake noise reducer which just dulls the pads. This is best used when brakes are first installed. This is only a band air and should be used lightly. If you are still having these problems, switch to a better material like ceramic pads

More Brake Noise Reading.

You mention to anyone that you work on superchargers and instantly their first question is; Can I supercharge my car? This time the question was; Do you have a Nissan Xterra Supercharger I can put on?

Here is the deal. Adding a supercharger to a car without one runs about 3-5K. Yes, $3,000 – $5,000. You are not plugging in something, you have to modify the whole engine. So in this case, if you have the smaller 2.4L or 3.3L engine, you are better off just selling your ride and buying one that came from the factory with a Nissan Supercharger already on it.

I get that most people do not understand what a supercharger really is, but at least know that a supercharger engine is completely different than one without it.

What the hell is the AC Compressor dessicant element? This is a good question.

Older vehicles used to use a metal drier as the filter in the A/C System. Starting in the late 1990’s, the Toyota AC Compressor began using dessicant elements instead. They recognized that servicing the A/C System required changing this out. These dessicant elements are much easier to replace. Most condensers have a cannister on the side of them, see picture. You open the top of the cannister with a 10mm hex nut and change out the dessicant. If the old one is black then you’ll need to change the whole condenser.

As you can see in the picture, the dessicant looks like a long tea bag. It is the same thing you find in your shoes, just a finer grain. The dessicant pulls moisture and debris out of the refrigerant. While refrigerant is a liquid, water in the system can be a big problem.

I was working with someone who had a kit car. It was a classic mercedes that required a Mustang manual steering rack.

I was fairly impressed with the price and availability for these. Apparently alot of companies are building kits that use this Ford Steering Rack. Who would have thought a 70’s Mustang II steering rack would still be so popular?

They can also use power racks, which are nice if the car is bigger or heavier. If the car is lightweight and small I recommend sticking with power, since the power steering pump sucks power from the engine. Either way its nice to have a good supply of new racks and not have to worry about returing a core.

So I got a good tip on an a car parts coupon. The website CarPartsWarehouse.com has a special promotion. I think it is designed for certain repeat customers , but anyone can use it.

Enter: P9Z5N2 at the coupon box and get 10% off your order.

Not a bad little deal. They seem to have a good selection of A/C Parts, Rack and pinion Steering, turbos, supers, electronics and more.

If you know of any good deals or coupons about auto parts, be sure to let us know. We’ll happily post them here.

So the current question is what is the best AC Compressor? This is a tough question because every compressor is unique and therefore only a few people build or rebuild that specific compressor. You have to review what is availablel for your vehicle

If I had to take a stab at it for the OEM’s; I would say 1. Nippon Denso – They invented quality manufacturing 2. Sanden – another great Japanese builder 3. Delphi – struggling to stay alive, but the parts still seem to be good. Once again, please remember you cannot use a Denso for your Dodge AC Compressor, it just doesn’t fit.

They other options are tough to break down. I would avoid used entirely, just not worth it. Reman units only if you cannot get new. The best option is often aftermarket new. These are new compressors just not made by the original manufacturer. Just like you car came with Firestone tires, you can put Dunlop or any other brand on when they need to be changed. Same is true for Compressors, you just have to get the part from a quality builder. Our sponsor will appreciate this, but DiscountACParts.com does make an excellent line of aftermarket compressors. I have gotten very good feedback on their parts, if they have one of their brand compressors available, I would definately go with that. They have a great warranty too.

Working on on some Honda Parts and had this strange question. When do you know the ac evaporator is bad? In this case it was an 2002 Honda CRV AC Evaporator and they weren’t sure.

The answer is; its tough. Not a good answer, but the evaporator can 1. Leak, 2. Have damage or 3. Be contaimated. Any of these are reasons to replace the unit.

The difficulty is not changing it out and they are not even that expensive, compared to other car parts, its just they are very hard to get to. Often up against the firewall which makes them take forever to get to.

So I was watching a friend work on a 1996 Mitsubishi Eclipse Turbocharger. He had purchased an upgrade turbo for this vehicle that I was excpecting to be a ton of work to install. Turns out it was a drop in replacement that really gave a boost to the engine. No modification required and I couldn’t believe it.

For those curious, it was a T28 Garret turbocharger that provides up to 400hp, 600cfm flow all in a ported turbine housing. Real nice upgrade if you are looking for it. Purchased at turbochargerpros.com part number 40-30001 N. Their N is the drop in upgrade. The HP requires down pipes and other modification

If you have a Mitsubishi Eclipse (DSM era) I would highly recommend this upgrade. Easily worth the money if you are into speed.

So yesterday we discussed expansion device systems. Today we are going to look at orifice tube based systems.

On some auto air conditioning compressor sytems they use an accumulator and an orifice tube. Chevrolet AC Compressor systems use this setup frequently. In this system the pressure is accumulated in the accumulator and hence the name. The orifice tube catches debris at the low side of the system

The orifice tube is in line on the return side of the system. You usually have to pry it away from the hose to get it to fit in there. The orifice tube should be changed with any ac compressor change or any system cleaning.

So I’ve gotten a few questions as to understanding pressure relief in an AC Compressor System. The answer is in the expansion device. Most ac systems use an expansion device to release pressure in the atmosphere. This can either be an expansion valve or an expansion block, see picture for more on the difference, but essentially they do the same function, just different designs. The valve has an external sensor arm while the block is pressure based

Both of them have a relief valve internally that will send excess pressure into the atmosphere. This ensures that the air conditioning compressor doesn’t blow up because of excess pressure.

In action the circle in the picture at top of the block (hidden on the valve) raises up if the pressure is too high and the air escapes. Without this relief you would quickly destroy compressors.


We’ll discuss accumulator and orifice tube systems tomorrow so check back.