Notes on Cleaning Up Fuel System Deposits | Oil Additive Information Links |
Other Approaches
There are other approaches
to the fuel system cleaning besides adding aftermarket fuel additives.
One is to use water as described in many of the messages posted to this
list, one is the fuel tank/vacuum induction fuel system cleaning approach
that many quick oil change places use and one is the high tech, expensive
(some of these machines cost $4000), and complicated machine approach.
Water is a great deposit remover. It is just like steam cleaning the combustion
chamber.
Unfortunately, the
heavy components of fuel and fuel additives are liquid during the combustion
process and don't get completely burned. About 25% of the active fuel additive
components (the oligimeric detergent and fluidizer components) end up in
the crankcase. These components may or may not be compatible with the oil.
As you can imagine, water does not burn. It may leave through the exhaust
valve as steam or it may end up in the crankcase. Do you want 25% of the
total amount of water used in the cleaning process to end up in the crankcase?
You can change the oil right away or you can run the engine long enough
and at a sufficient speed to distill off the water. After any of the serious
fuel system cleaning, the oil should be changed anyway. You can draw your
own conclusions about the effects of water in the crankcase and the prospects
of getting all of it out, but you can clean up the engine just as effectively
without the use of an oil insoluble actor. There are some systems out there
that use water in the fuel system cleaning. I think these systems usually
employ some kind of very expensive machine. I don't think they clean more
effectively than the fuel tank/vacuum induction fuel system cleaner. Cars
are sensitive to deposits, but not that sensitive.
The fuel tank/vacuum
induction fuel system cleaner cleans injectors, intake valves and the combustion
chambers through the action of the bottle of additive poured into the fuel
tank. The vacuum inducted intake system cleaner is added through a vacuum
line behind the throttle plate. The purpose of the intake system cleaning
is to remove deposits left by the PCV and the EGR as well as aiding in
cleaning up the intake valves, ports, and combustion chambers. One brand
that is very effective and provides a high quality product is C.A.T. Products
makers of Run Rite.
The tool used to induct
the intake system cleaner into the vacuum line is usually a metal bottle
with a tube in it that connects to a hose with a fitting on one end to
connect to a vacuum line close to the throttle plate on the vacuum side.
There will be no problem as long as the engine is running, it will suck
in the cleaner. If the engine stops but the fluid keeps flowing, you can
hydrolock the engine and damage valves, rods, pistons and gaskets. These
tools often have a valve in line and a clear portion in the hose after
the valve to adjust the feed and monitor the flow so that it is a steady
drip. The fluid usually used in the bottle is an air intake/throttle plate
cleaner package. Only the additized fuel in the tank goes through the injectors.
Based on what I have seen, this should work as well as any injector cleaning
scheme on the market. Fuel injectors deposits are not as much of a problem
now as they were a few years ago. New injectors are more resistant to deposits
and most gasolines, as poor as they are at controlling most deposits today,
still can keep injectors (and carburetors) clean. STP Fuel System Cleaner
works very, very well. Two bottles should have them spotless and will clean
the valves, ports, and the combustion chambers. The fuel tank/vacuum
induction fuel system cleaning makes an immediate difference in the way
the car runs. It must have something to do with the EGR and PVC deposits.
You can also try to replace the PCV. The beauty of the vacuum induction
fuel system cleaner approach is that it doesn't require a degree in mechanical
engineering and a master mechanic certification to operate: pour a bottle
in the tank then find a vacuum hose and suck a bottle of the intake system
cleaner into the intake. I don't think the systems that utilize the expensive
machines actually clean the fuel system any more thoroughly.
The problem with the
machine systems hooked up to the fuel rails is that they can not clean
the parts of the system that the fuel does not get to. Cleaning through
port fuel injectors can clean the injectors, intake ports, intake valves,
and combustion chambers. Cleaning through the vacuum line cleans
the entire intake manifold, intake ports, intake valves and combustion
chambers while the fuel additive added to the tank cleans the injectors,
intake ports, intake valves, and combustion chambers, albeit at a slower
rate as the fuel in the tank is burned over about 350 miles. I think the
fuel tank/vacuum induction fuel system cleaner approach may, in fact, provide
a more thorough cleaning. I personally do not believe that the expensive
and complicated machine/high pressure systems have any advantage over the
simple approach that we are using. They do, however, have a major drawback
in that there are more things to go wrong. The technician has to disconnect
the fuel pump and connect to the fuel rail. There is big potential for
disaster with this approach if the technician is not highly trained. It
is pretty easy to pull off a vacuum line and suck in the cleaning solvent.
If the vacuum line is not reconnected properly, the car will not run, but
it is easy to diagnose and fix. It is also unlikely to burn the car up
if the technician doesn't do something right.
The walnut shell blasting
can be done without removing the head. It is a fairly difficult operation
and requires the right equipment. You also have to make sure you remove
all of the residual walnut shell. All in all, the aftermarket fuel additive
packages or the fuel tank/vacuum induction fuel system cleaning are probably
the least intrusive approaches.
1. Synthetic Base Stocks.
Group IV base stock is made of PAO and was for a while the only base used
in synthetic oil until Group V (Esters) came along. PAO has a property
of shrinking rubber gaskets, and when older cars were switched the leaking
was generally due to this fact. Cars with new gaskets that used PAO-based
oils from the beginning did not encounter shrinkage or leakage. The newer
and the better synthetic oils began to incorporate a new base stock (group
V -Esters) that helped to keep the rubber from shrinking. True synthetics
are generally Group IV (PAO) mixed with Group V (Ester) base stocks, like
Mobil 1, Valvoline Syn Power, and Amsoil. Mobil began using straight
PAO, but switched to a very good blend of the two. Their additive package
seems to be among the best. [Email from Mobil Products: 1. Mobil
1 Tri-Synthetic is a blend of alkylated naphthalene (Group V), PAO (Group
IV) and ester (Group V). The alkylated naphthalene is for improved deposit
control. The Mobil 1 Tri-Synthetic Formula 15W-50 is A3/B3-B4-98
approved. Mobil Delvac 1 is B4-98, E5-99, SJ and CH-4 approved. Mobil
Delvac 1 is a proprietary blend of synthetic base stocks formulated for
optimal performance in diesel and gasoline engines.] [Comment from
Geoff William: The first component (alkylated naphthalene) has the
advantage over PAO and esters in that it has the best additive solubility
and the best seal compatibility of the 5 most common engine lubricants
(PAO, esters (2 types) and mineral oil).
This is great news for older cars, with
brittle seals that might be more suceptible to shinking with a PAO and
ester-only based synthetic motor oil.] Castrol does not produce a true
synthetic motor oil. Castrol Syntec used to be a GIV base but it was switched
in the early 90's to the much cheaper GII base. Technically it is
a hydrocracked petro-based oil. If you want a synthetic do not spend
the money on Castrol Syntec, you are much better off using Mobil 1 (the
best oil for your money). Penzoil uses the same base stock as Syntec in
their regular "cheap" oil. "Pure-base" is a what they call the Group II
base. Group II and III are nearly as good as synthetic based oils but cost
almost the same as conventional oils to manufacture. On the
plus side Syntec does use one of the best anti-wear additives, Moly-DiSufide.
BUT they are ripping you off charging as much as they do.
2. Oil Longevity. Synthetics
are designed to last longer than conventional oils. Changing the oil every
3000 miles with synthetic oil or even Castrol Syntec is a complete waste
of money. IMPE, using Castrol Syntec (what was provided during the free
service period) in my Turbo Diesel (VW TDI) for 10,800 miles (the recommended
change interval) it was found through oil analysis of the oil taken out
of the engine when it was changed that it hadn't broken down, and the additives
were not depleted enough to warrant changing. That was after nearly 11,000
miles in a turbo diesel. Your Volvo puts less depends on an oil than my
TDI running up here in Michigan at below freezing temps, and the oil still
lasted that long.
What was the manufacturer's recommendation
for drain intervals on the motor? Our '86 is supposed to be changed every
5k miles. And it has for 220,000 miles. Doesn't burn or use any oil and
it has had regular dino (petroleum) oil in it for the life of the car!
I am switching the oil to a synthetic blend of Group III and Group IV/V
base stock to add protection and because I got a deal on buying 2 4 gallon
cases of oil. A 3,000 mile oil change does not make sense for any
car unless you are racing it or you drive less than 10,000 miles a year.
The Jiffy Lubes of the US have brain washed the public into thinking that
changing the oil every 3000 miles is needed. Hogwash!!!! For $15 you can
have your oil analyzed to determine if you are changing it too soon or
waiting too long. Using Synthetic oil you can double, triple of quadruple
your change intervals. I know some Amsoil dealers and their customers all
run over 10,000 miles per change, and the cars that see lots of stop and
go driving get an oil filter change in between.
My recommendation for you is to stop throwing away your money and to stop wasting natural resources. If you want to use Syntec that is fine but be aware that you are paying double what you should be based on what the oil is made of. Increase your oil change interval unless you drive less than 10k miles per year. If you use a real synthetic oil like Mobil 1, change the oil every 10,000 miles or every 6 months which ever comes first. The information you have provided doesn't mention mileage driven in a year a big factor in choosing oil. If you want the best for your engine, get a real synthetic in there.
3. API Standards. The standards set by the API are very easy to meet. Look for the Chevy Corvette standards (GM 4718) if you want a good oil. Or if you want the best protection against wear use an API CH-4 rated synthetic oil. Anyone can make an oil meet most standards, but the standards don't look at the amount of caking or sludge deposits. The additive package and the Viscosity Improvers have more to do with longevity and do not affect the passing of tests but do affect the long term health of your engine.
4. Viscosity. Per the SAE (Society of Automotive Engineers), viscosity is a measure of an oil's thickness, or resistance to flow. Lower numbers indicate thinner oil and higher numbers indicate thicker oil. There are two types of motor oils, single grade and multi-grade. Multigrade oils such as a 10W-30 are designed to have the viscosity of an SAE 10W oil at cold temperatures combined with the viscosity of an SAE 30 oil at engine operating temperatures, The "W" or "Winter designation indicates that the oil meets viscosity requirements for low temperatures (below 30°F). At the Chevron site http://www.chevron.com/prodserv/lubricants/products/oil-labels.html there is a nice SAE Viscosity Grade guide at the bottom of the page.
As an illustration, the Kinematic Viscosity is measured in centistrokes, the higher the number the thicker the oil (65 is thicker than 55) The Viscosity Index can be interpreted as an indicator of how thick the oil is, the LOWER the number the thicker or more viscous it is.
The following is for a 5w30 and a 0w30
made by the same manufacturer (synthetic based oils: Group IV and V blend)
Kinematic viscosity @ 100C cST (ASTM D-445 test) 11.5 and 11.3
Kinematic viscosity @ 40C cST (ASTM D-445 test) 66.00 and 57.3
Viscosity index (ASTM-D2270 test) 170 and 196
Now if we compare Castrol and look at the
5w30 compared to the 10w30 (Group I base stock nonsynthetic:)
Kinematic viscosity @ 100C cST (ASTM D-445 test) 10.7 and 11.3
Kinematic viscosity @ 40C cST (ASTM D-445 test) 63 and 80
Now in the same line of oils, a "monograde"
SAE 30:
Kinematic viscosity @ 100C cST (ASTM D-445 test) 11.2
Kinematic viscosity @ 40C cST (ASTM D-445 test) 93
Quite a bit of difference there. . .
Here is some data from Chevron on their
Supreme Motor oil (all Group II base, just like Syntec except they also
sell a true synthetic:)
(numbers below are for 5w30 and 10w30 and 30, respectively)
Kinematic viscosity @ 100C cST: 10.4 and 10.4 and 11.5
Kinematic viscosity @ 40C cST: 62.5 and 69.8 and 101
Viscosity index: 155 and 135 and 101
Again the oil is thicker as the first number
increases.
Here is QuakerState: 5w30
and 10w30 and 30 (all Group II base, just like Syntec except they also
sell a true synthetic)
Kinematic viscosity @ 100C cST: 10.7 and 11.0 and 11.2
Kinematic viscosity @ 40C cST: 67 and 73.2 and 90.5
Viscosity index: 155 and 140 and 113
Here is Penzoil: 5w30 and 10w30 and
30 (all Group II base except for the straight 30 weight which is a Group
I or solvent refined oil)
Kinematic viscosity @ 100C cST: 10.5 and 10.5 and 11.5
Kinematic viscosity @ 40C cST: 60 and 67.0 and 98
Viscosity index: 160 and 140 and 105
Remember that the 5 is just for start up and gives you better protection if you start you car often, and the last number is what your car sees in operation, But it is possible for a 30 to be almost as thick as a 40 weight oil. The 30 will in some cases give you better fuel mileage than a 40 weight.
The heavier weight synthetics are designed for cars that are burning or leaking oil not for properly running cars. There is a market because some folks have been running synthetic and recognize how superior it is but wind up with a slight oil leak. Switching to a heavier weight synthetic will help reduce oil consumption. But using a 5w50 has some other problems besides creating a thick film of horsepower-robbing resistance, it stretches the limits on stability over time. The viscosity improvers needed to have a 5w50 (the w stands for winter) displace some of the lubricating molecules and are the first component to break down and create deposits in your engine.
Volvo does not recommend a single grade for the motor. They recommend multi-grades for their engines. Single grades should only be used as per manufacture's recommendation.
Viscosity Index improvers are mentioned
at Lubrizol in a New York taxi test: http://www.lubrizol.com/products/core/vmodifiers/fieldtest.htm
This test was much different than the
Consumer-sham-Report/Review test on NYC taxi cabs, the results are more
meaningful. In summary, "the New York City taxicab fleet test provides
persuasive evidence of the outstanding performance of Lubrizol viscosity
modifiers. Despite the severe operating conditions, Lubrizol viscosity
modifiers, combined with the Lubrizol performance package, provided superior
engine cleanliness and durability. Further, they maintained their remarkable
rheological characteristics over the extended drain intervals of the test,
providing consumers with additional confidence that their cars will start
and operate reliably in all weather conditions.
5. Break-In Period.
The issue of using a dino/mineral oil as a break in oil is somewhat overblown.
And since you are using Syntec, you are still using a mineral oil, NOT
a synthetic oil. Like I said before, Syntec is a highly refined and stabilized
MINERAL oil, it is not a synthetic in the terms you are thinking.
Regular oils, Dino - mineral - petroleum - whatever you call them, are
most commonly solvent refined, a process that leaves many impurities in
the oil. Castrol and many other companies now are using the hydrocracking
process that refines the crude oil without using solvent separation, resulting
in an ultra clean pure product. BUT IT IS STILL A REGULAR OIL.
If you want to switch to a synthetic oil wait till you have 10-20k miles
on the engine. At that point your car should be 'broken-in' enough for
you to feel comfortable about using a REAL synthetic.
A couple comments about break in myths
and synthetic oil consumption after switching: Most break-in periods in
new engines will be accompanied with some oil consumption. If this is not
the case for a particular engine switching to synthetic early will not
prevent normal break-in. The extra slipperiness of a synthetic might prolong
the period but it will provide extra protection and as long as you don't
beat up the engine by over revving it too much or loading the car up and
climbing a mountain before it is broken in you should be fine.
6. Switching to Synthetic Oil. As far as switching from normal oil to synthetic I think that it is better to change over all at once, but you will need to make two or three changes before resuming or beginning normal change intervals. I would put a full crankcase of synthetic in, drive it for 1000 miles, change the filter, drive 2000 miles and change the oil and filter, and then change both after 3000 miles then begin either 5, 7.5 or 10k mile oil change intervals. The filter changes are important because the new oil will be removing lots of deposits and sludge and you don't want to overload a filter. The extra cost and time spend with the first few changes will be rewarded with a smoother running car, lower costs (extended drain intervals, and if the proper viscosity is chosen fuel savings) and a nice clean running engine.
Check out these sites for more info on oil:
Fuel Economy Issues. See Lubrizol's
discussion of the effects of base oil on fuel economy at: http://www.lubrizol.com/referencelibrary/newsline/1997/novnews97.htm
[Williams:] My personal experience is
in line with this and I have seen an increase in Fuel Economy of 10% (24
mpg to 26.5 mpg) since switching from a Group I 10W-30 to that Group III/IV/V
0W-30 blend I have mentioned before.