Yuck, It's Dirty...

This article is written for OE setups. Some things will vary if you are installing performance parts.

Engine oil is some pretty amazing stuff. It has to operate continuously in one of the harshest environments on the planet. If it fails so does your engine and usually rather quickly.

The lubrication system in an engine is very complex. Every passage is carefully planned. Bearing clearances have to be tight enough for parts move properly and loose enough to allow adequate oil flow. If one spot flows too much oil, one or more other spots could starve resulting in very short engine life.

The Players

Where's it going and how...

The Oil Pump and Pressure Regulator

The pump picks up unfiltered oil from the pan. (There is a screen in the pickup but it only stops big stuff.) The oil pressure is limited by a regulator, which often built into the pump but can be in the block. The regulator is always located between the pump and the oil filter.

The Oil Filter

The oil goes is pumped thru the filter before going to the rest of the motor. The filters used in Fiero are non-bypass types. This means they do not contain a bypass valve. Most do contain an anti drain back valve. Oil flows from the outside of the media to the inside. (I.E. The oil enters thru the ring of small holes and exits thru the threaded opening.)

The Valve Lifters

Many people forget that hydraulic lifters are also little oil pumps. The lifters are the only source of oil flowing to the rockers in a pushrod motor. A common mistake during cam work is failing to prime the lifters. It's usually not a fatal issue but it does mean the lifters take that much longer to oil the valve rockers.

To prime a lifter simply place it in a container with enough oil to cover it. Compress the lifter several times to drive out the air in it. Yes, this is harder with roller lifters. You can use an old pushrod as a priming tool. (I used to use a cut off push rod with the cut end stuffed into a wood block. This makes really easy work of it.)

What does oil do?

Without getting technical... Oil has three jobs.

Obviously it is a lubricant. The oil film keeps the two bearing surfaces from actually touching.

It is a coolant. The oil caries heat away from all the places it flows. Oil is the only coolant for things like the wrist pins and rod bearings.

It is a garbage collector, carrying metal and dirt particles out of the bearings.

Oil Weight

5W-30 is the normal oil for Fiero. The W? Think Winter. That is the weight the oil will shift to when it's cold. In really cold places you might want to use 0W-30 and in warmer places 10W-30. (See API web page, SAE Viscosity Grade.)

Using heavier oil, such as 20W-50, isn't always a good thing. It can even do damage because heavier oil will always flow more slowly than a lighter oil, even slower in cold weather. For most people, staying with something in the 5W-30 to 10W-40 range is best. People in hotter climates or running certain high performance setups may need the heavier oil. (Warning! The bearings in many turbo and super chargers are configured for specific oil weights. Using heavier oil than specified can quickly trash the turbo bearings.)

Lowest expected outside temperature	Typical SAE grades for cars
0°C (32°F)	5W-30, 10W-30, 10W-40, 20W-50
-18°C (0°F)	5W-30, 10W-30, 10W-40
Below -18°C (0°F)	5W-30

(Source: American Petroleum Inst. Engine Oil Guide from web page. )

How Much Oil Do I need?

That depends on a couple things.

I believe Pre recall 84 L4 originally specified 3.5 quarts. Post recall 84 L4 and all other L4 and V6 specify 4 quarts. (Pre/Post recall means that recall 84-C-15B and/or 88-C-23A hasn't/has been done.)

You may actually need more than the specified amount. This is usually the case when the longer PF52 filter is used on 1985 and later engines. Using the PF52 will bring the 85 and later engines up to about 4.5 quarts capacity.

The rule with most of the OE Fiero motors is to pour in 4 quarts and start the car for a minute or three. Then check the level and bring it up to the full mark. (With 84 L4, start with 3.5 quarts.)

I always fill to the full mark on a cars dipstick regardless of specified capacity. NEVER run any motor low on oil. Transverse motors are very prone to pressure dropout when cornering, low oil will make this problem much worse. As far as I'm concerned you should be adding oil BEFORE the level drops to the add mark let alone below it.

Yes, this means you may not always add a full quart. Better to add oil more frequently than allow oil pressure dropouts. Every time a dropout occurs the engine is effectively running without oil. The more dropouts you have, the shorter the engine's life.

Oil Pressure

A blow off or bypass valve, usually mounted in/on the oil pump, regulates oil pressure. Oil pressure should stay within the specified range at all times. Oil pressure that swings out side the specified range is very often an early sign of engine problems. (BTW. Most stock GM OP senders will only read to 80PSI max.)

V6, VIN-9, 30-45 PSIG

L4, VIN-R, 36-41 PSIG

(Source, ALLdata)

Oil pressure should stay within the specified range at all RPM. In very cold weather, oil pressure may be a bit higher than normal until the engine warms up a bit.

Always test oil pressure with a mechanical gage! Don't trust an electrical one that can be thrown off by a flaky sender or bad grounds.

High oil pressure can be almost as bad as low. Excessive pressure can distort the filter and even rupture it or blow the filter gasket. It can create internal problems as well. Depending on the engine, some oil passages are blocked with gallery plugs, similar to freeze plugs, which could blow out under high pressure. If this happens the engine will usually have no pressure. (VIN R and U motors have at least 1 such plug behind the timing gear on the cam.)

First oil

After a rebuild, no mater how well the block and everything are cleaned; there is always some junk that washes out. After an engine is stored for who knows how long, God only knows what will end up in the oil pan.

This means you should expect that you might need to change the oil again in 500-1000 miles. Maybe even less. I recommend using regular crude based oil for one main reason... While there is debate over seating rings, etc, with synthetic, you want regular oil because it's cheap. It just doesn't make sense to use expensive oil for that short interval.

Which oil is best?

In general, there is no best oil. Any decent brand of oil will meet API service category SJ or SL. (SL is the newest but there is still a large amount of SJ in inventory.) When Fiero was built the API service category was SE or SF so nearly all retail products will exceed Fiero's original specification.

Mobil 1, if you can afford it AND your motor is in good shape, is nice stuff. If your motor has any known lube problems, like leaks or smoking, don't use it or any other synthetic until they are fixed. This stuff is too expensive to be dumped on the ground or fed out the exhaust.

Your individual driving habits and vehicle setup will ultimately determine the best oil. Before settling on a brand, read the oil makers web sites. Mobil 1 has a number of articles that should help you decide on brand, weight, etc. The oil makers all want you to buy their stuff but most seem to want you to pick the right stuff for your application, even if that means staying with the less expensive crude based oils.

Specialty oil

Do any of the specialty oils, like Valvoline MaxLife for high mile engines, actually work? I don't know and even if they do, it would depend on your specific engine how well. There is some concern about these products with the main issue being that long-term use of some of these products might over soften seals and cause leaks.

So far MaxLife seems to be well received by the market. There are so many of these purpose blended oils now that it's hard to keep track of them. Before choosing one, check the makers' web sites and keep in mind that no oil or additive will reverse mechanical damage to a seal. The best you can hope for is some softening and swelling of an old seal to buy some time before replacement is forced.

Does Synthetic oil cause leaks?

No but if you have any small ones, the stuff can find them and wash out the dirt in the gap. That can make it seem like the synthetic caused the leak. The engine already had a problem that the synthetic simply exposed.

Modern synthetics have chemicals that swell seals the same way regular oil is supposed to. Some early synthetics lacked these chemicals and the seals would shrink. In some cases the seal conditioners in synthetic oil may extend the life of aging seals, but again that will depend on the condition of the engine at hand.

Synthetic means no Crude...

Not according to Castrol and some others. Castrol Syntec is made from specially treated Crude base stocks. Car & Driver and Lubricants World, a lube industry trade publication, have reported this issue. Castrol Syntec sells on the same pricing levels as Mobil 1's PAO based oil but the stuff costs far less to make. Personally I consider this an act of consumer fraud and won't use or recommend it.

See at KLOTZ for more info on which "Group" of oil.

Do magnetic drain plugs work?

Yes! They don't trap a huge amount of stuff but everything on the magnet is that much less getting back into the motor. They will attract any size of magnetic particle that gets in range, even really small stuff that might pass thru the oil filter.

They can also give you an early warning to major problems. If the thing is ever covered with coarse trash then you've got something going on that shouldn't be.

You can get magnetic plugs at most parts stores. They are often sold under the OilTite line from MotorMite. They only cost a few dollars.

What Filter do I need?

Note: GM/ACDelco has change maker and PF52 is shorter and cheaper made. See notes below.

This can be confusing. At the moment we'll stay with just the AC Delco numbers.

All V6 specified PF47.

84-87 L4 specified PF51 in TSB 88C23 (Engine Fire Recall), which has been superceded by PF52.

88 L4 specified PF1072

Officially, the filter makers will all tell you to only use the filter listed in their catalog. They don't want to take the chance that some alternate will screw up you engine. Many people use the PF52 filter on all Fiero engines that have room for it. Besides the increased filter surface area, you get a slight increase in total oil capacity and it is easier to reach at service time on L4.

If you use filters in the Allied Signal (They make Fram and other brands) numbering system the long filters are xxx3980. The xxx prefix of the number will vary depending on the brand/grade the filter is sold under. Typical Fram prefixes are PH and PHA. Some Allied Signal numbered brands, I believe Castrol is one, only offer the long filter.

88 L4, and all VIN R or U, motors with the filter in the oil pan use PF1072. Although you do have a selection of different filter media, this motor doesn't have the option of a larger filter.

PF52 change notes

PF52 has change, read these links:

AC Delco PF52 oil filter has shrunk and The New AC Delco PF52 - Buyer Beware! in PFF

ACDelco Launches Redesigned OE Oil Filter

ACDelco Newsletter in PDF doc

Filter Install Notes

Most people over tighten filter and worse, use a wrench to tighten... Typical instructions:

Lube filter gasket with new oil.
Tighten 3/4-1 turn after gasket contacts the base.

Most people can tighten by hand force. Using a wrench to tighten? Then be very careful and not over tightening or dent/crush the filter. (Some "wrenches" are great for damaging/destroying the new filter.) Use a marker if needed so you can see what 3/4-1 turn looks like.

What Filter is best?

This is another minefield. I have a real problem with any filter claiming they are better than another. (Even among different products in the same brand.) Here's why.

All the filters test against SAE specifications. The problem is that these specifications are not readily available to the public. In most cases if you want read them, you will pay a hefty fee to get them from SAE. Even then the specifications are beyond the general public's ability to understand them.

This makes the tests rather meaningless. For example: one filter claims that when tested to an SAE spec it has 50% increased dirt trapping capacity vs. another filter, and it costs 3 times as much... Well if you are talking about the standard short Fiero filters, you get at least 50% more capacity by simply changing to the long filter which most times costs the same as the short one.

To make matters worse there are Multiple SAE tests. If you take two competing filters:

Filter A does better than B on Test One.
Filter B does better than A on Test Two.
Both filters will likely try to claim they are better than the other and both will site only the unintelligible SAE standards as proof.

Filter construction

The filter makers all love to abuse each other over construction.... As long as the materials used do their job, who bloody cares what kind of springs and end caps are used? As long as the filter media holds its shape and doesn't leak, everything else is really totally meaningless to the average motor. All of the name brand filters meet or exceed the OE requirements for the Fiero motors.

If you are racing, then it matters. If you are running high volume/pressure pumps them you want good filters. Racing oil pressures could rupture regular filter cases or make them puke out the filter gasket. The high flow rates could collapse the media. Neither is a good thing. Some "performance" filters also have a hex nut on them that is drilled for a safety wire. (Safety wire may be required in certain race classes.)

Changing Filters

Some people and documents recommend changing filters every other oil change. I always recommend you change the filter with the oil every time. This isn't to make you spend money. It's to get as much dirty oil out of the system as possible. There's no sense changing the oil and leaving up to a quart of dirty oil in the filter.

Brands

Brand is at least some small indication of quality. At the very least you can check out many brand's product data online now.

Don't buy off brand filters. Some are ok but many are crap. There's no way to know which is which with them.

I also avoid the filters at quick lube places. Even when these filters have a brand name, they are often lower quality than the same brand's retail product. Many of them have shells like beer cans.

On the other hand, Store brands from larger chains are often pretty good. Many of the chains buy under contract from one of the big filter makers. These are worth checking out most of the time.

You've also got some obscure brands, like WIX, running around. These lines are often targeted at heavy industry, commercial vehicles, and/or racing. These brands may not have products for every car on the road.

Filter Bypass Valve

Nearly all motors have an oil filter bypass valve. In OE Fiero motors, the bypass valve is located in the block where the filter is attached. (This is true of all GM engines using AC PF47 or PF52 filters or the Fram equivalents.) In other setups, it can be in the block or built into the filter.

This valve opens only when the pressure difference between the filter inlet and outlet exceeds a few pounds. (About 7 PSI I think.) When the valve is open, oil flows unfiltered into the engine. Under Normal conditions, this valve will hardly ever open. The oil has to be very cold or the filter very dirty to make the bypass valve open.

Some people advocate elimination of bypass valves but this is actually a really bad idea. Without this valve the filter media can collapse resulting in restricted oil flow. That could kill the engine depending how bad the restriction is.

Keep in mind that while Mobil 1 will flow down to -65F, many crude based oils start getting stiff at +20F. This stiff oil can easily trash many filters if there is no bypass valve.

(Bypass valves are commonly eliminated in Fiero running V8 engines.)

Part Numbers

If you ever need a new bypass valve...

84-87, L4, VIN R, Oil Filter Bypass Valve, AC DELCO 25010497

V6, VIN 9, Oil Filter Bypass Valve, AC DELCO 25014006

88, L4, VIN R, Oil Filter Bypass Valve, AC DELCO 25014006

(Source: ACDelco.com)

Always double-check the numbers before ordering. Part Numbers do change. These numbers may not be right for all years.

What does Ogre use and why...

I started using Mobil 1 when the motor had around 140,000 miles on it. I didn't have any significant leaks or any other problem because of it. My engine has been pretty well taken care of by the previous owner and me. For filters I'm just running standard Fram PH3980's with the grippy paint. The short filters work fine but I can't reach them to change them.

Why Fram? I've never had any problem with them. I just like orange I guess. (It's as good a reason as any when you start to look into filters... It's a close race between the oil people and the filter people who can produce more bullshit.) If they are out of Fram, I use AC Delco or some other known brand.

Mobil 1 is generally considered to be one of the best oils there is. It works well for me. If you get the 5-quart jugs when they are on sale at Wal-Mart it's not as expensive. Price wise you're getting a quart free like that. I usually run 5W-30 or 10W-30. (Wal-Mart only caries the 5-quart jug about twice a year.)

My change interval is probably more like 4000-5000 miles. I don't beat the car. I get a mix of decent runs with some stop and go. I'm using better oil with a long filter. I've also got one of the magnetic drain plugs.

Recycling

Used oil is a huge environmental problem. Please don't dump it on the ground or into storm sewers.

You can return used oil to most chain stores with service centers. Pep Boys and other such places will take it. While they may be legally required to, small service stations may or may not take it. Some states, like Delaware, have additional programs. Delawareans, and nearby residents of MD and PA, can put oil into the Recycle Delaware bins 24/7 even on holidays. The Recycle Delaware program also has filter disposal bins. (Filters are crushed to extract oil and the metal is sold for scrap.)

If your area won't accept used filters... Punch a hole in the dome and let them drain overnight before trashing them. They will drain faster and more completely if they are kept warm.

New Technology

Many newer cars have an "oil life monitor" installed. There are two kinds of monitors used.

The most common method in GM cars seems to be a program running in the PCM. In short, when the car goes X miles the light turns on. It's basically a high tech version of the Jiffy Lube cling label they put on your windshield. It's a pretty dumb system that can't fully account for using Synthetic oil, driving conditions, and many other factors. To make them even more annoying, there is no standard way to reset the thing even across GM products.

Another, more intelligent, system is marketed by Delphi and likely others. In this setup, there is actually a sensor in the oil pan that continuously monitors oil chemistry. Software in the PCM uses this data to tell you when to change oil. When properly programmed, this system can account for many of the things the above method cannot. If this system says change the oil, you better listen.

Starting Dry Motors

There are two kinds of dry motors...

Rebuilding

When you are rebuilding a motor, use assembly lube. This light grease is specifically designed for engine assembly and will hang around until the oil washes it away after startup. It provides far more protection than using engine oil. Assembly lube should be applied to all cam lobes/bearings, rocker tips and pivots, and any other thing that needs it.

Stored

An engine stored long term will dry out almost as much as a rebuilt one. Just what you can do depends what motor is involved.

Starting for the first time

Before starting the motor, grab some kind of spray oil and spray some into each cylinder. (If possible into the valve cover(s) of a stored engine. Bend the straw to oil as many rockers as possible.) Oil like Valvoline SynPower spray oil or CRC 556 will work better than a high solvent product like WD40 but WD40 will do.

Leave the spark plugs out and crank it over 2-3 turns by hand. Yes, even rebuilt motors. If you can't crank it over by hand, odds are good that something could break if you hit the starter.

Most people know to prime the oil pump before starting the engine. On engines that allow it, you can make a priming tool from an old distributor shaft. (I think Fiero V6 allows this) Many engines don't provide easy access to the pump drive. In that case, disable the ignition and fuel injection then crank the motor until oil pressure registers. (Don't crank it too long and cook the starter.)

People often forget that priming the oil pump doesn't prime the lifters. Even if you manually prime the valve lifters during a rebuild it will still take them some time to pump oil thru the pushrods. So don't panic when you first start the thing. If the lifters aren't pumping after a minute or three then either a lifter is bad or the pushrod is plugged.

Disabling OE Fiero Motors

WARNING! Disable the ignition by unplugging the ignition module or the low voltage side of the coil. NEVER pull off high voltage wires!

If you pull of the high voltage wires, the spark energy still has to go someplace. It can feed back into the ignition system and if it doesn't fry something immediately, it will likely weaken the system so it fails later.

On DIS L4, unplug the two-wire connector from the ignition brick. That will kill power to it.
HEI L4 or V6, unplug the ignition module.
To make sure the EFI is dead... Pull the fuse for the fuel pump.

The EFI goes dead in many systems if the ECM doesn't see the reference signal but kill the pump just to make certain.

Links

The American Petroleum Institute represents most oil producers in the U.S. They also have another site, API Used Motor Oil Collection and Recycling.

The Filter Manufacturers Council represents many of the filter makers in North America. Some interesting reading and links to info on filter recycling.

The Delaware Solid Waste Authority has info on Delaware's recycling program. (Such as it is.) It includes views of the "igloos" used here. (Most of them were originally igloo shaped. Now they mostly all are just dressed up dumpsters.) Only a few facilities have the oil and filter igloos.

Earth 911 can help you find commercial and municipal oil/filter and other recycling information for your local area.