Fuel, Additive,  Lubricant and Coolant Reference
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 Volvo Maintenance FAQ for 7xx/9xx/90 Cars                                                                                                                     Version 5.0
Notes on Cleaning Up Fuel System Deposits

Coolant Information Links

Oil Information Links

Synthetic Oil Notes

Oil Filter Information Links

Oil Additive Information Links

Gasoline Information Links

Gasoline Recommendations for Turbo Engines

Brake Fluid Performance and Comparisons

Notes on Cleaning Up Fuel System Deposits [Mark Burns].
    Some of the high end aftermarket fuel additive packages are very effective at removing deposits in the fuel injectors, intake ports, intake valves, combustion chambers, and exhaust valves. One of the best products available is the STP Complete Fuel System Cleaner. It can out perform Techron and other Techron-based products like Slick 50 and Gumout Regane with respect to intake valve and combustion chamber clean up.  These aftermarket packages can remove any and all deposits in the system if used at sufficiently high or repetitive dosages although there is some risk of crankcase lube contamination. All deposits in the system are carbonaceous. The structure of the deposits in the injectors is different from the structure of the deposits on the valves is different from the structure of the deposits on the combustion chamber, but all are carbon based. The chemistry that is able to remove each type of deposit depends on the temperature profile that each area sees and the thermal stability of the detergent in the additive package.  Since October 1, 1993, all gasoline marketers are required by the federal government, according to the Clean Air Act Amendments, to deliver a minimum level of deposit fighting additives in their fuel. Up to that time, deposit control additives had been used to differentiate branded gasoline. The major gasoline marketers usually added at least a competent package to all of their grades. The lesser known brands rarely added any additives at all. About thirty percent of the gasoline sold were not additized. The minimum level of deposit control performance that all gasoline must meet are two standard deposit control tests-the ASTM D 5500-97 BMW intake-valve deposit test and the ASTM D 5598-95 Chrysler 2.2-liter port-fuel-injector test using a test fuel that encompasses the sixty-fifth percentile of U.S. fuel severity parameters. This federally mandated requirement for gasoline has established a lowest common denominator for deposit control performance.
    Gasoline additive suppliers have found ways to minimize additive dosage and "beat" these two tests. The result has been an overall reduction in the deposit control performance of U.S. gasoline. While a fuel marketer may have data demonstrating that their specific additive package once passed the BMW intake valve test and the Chrysler port fuel injection test, there are no guarantees that the gasoline they are marketing will provide adequate performance in any consumer's engine.  There are many commercial gasoline, available in the market today, including some major national brands, that, when tested in fleet test vehicles representing various drivetrain configurations, have developed more than 1000 milligrams on the intake valves. This is ten times the maximum amount of deposit allowed for passing the BMW intake valve test. There is even some evidence that the very low levels of deposit control additives being used by some gasoline marketers actually make the base gasoline create greater levels of intake valve deposits in the average engine than the unadditized gasoline would. It could be suggested that more consumers on the road today could benefit from the occasional use of a high quality aftermarket additive package than ever before. In some gasolines on the market, use of a high quality gas treatment package would certainly be advised if a driver wants a greater degree of certainty that their engine will be kept clean.

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.

Coolant Information Links.  Here are some links to informative sites about coolant and antifreeze topics:
http://www.team.net/sol/tech/coolant.html  This comes from the Triumph Car Club and discusses basic coolant information.
http://www.texaco.com/products/  This is the Texaco Dexcool product information site.
See the following reference web sites for information on automotive coolants:

Oil Information Links. Check out these great links to find out all/more than you ever wanted to know about oil:     http://rconcepts.com/beard/dragnet/drag/oilinfo.html

Synthetic Oil Notes.  [Tips from Geoff Williams]  I have spent the last 6 months learning about which oils will work best in my new VW TDI engine. In that process I have come across a wealth of information.  I'll state the following hopefully in a straight forward manner (BTW my wife is now the primary driver of our '86 240 wagon).

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:

The Mobil and Chevron oil corporations sell synthetics and have some good information on their sites.

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.

Oil Filter Information Links.  [Tip]  For a comprehensive (but very much embryonic) study on common brands of oil filters, see:
 and for the study in detail: http://minimopar.simplenet.com/oilfilterstudy.html

Oil Additive Information Links.  Thinking of using Slick 50 and other additives?  Check out these references for more information: Overall good advice is: always use high-quality lubricants at the proper viscosity range; never use additives, especially PTFE-based oil "enhancers."

Gasoline Information Links.  See for gasoline information: http://www.repairfaq.org/filipg/AUTO/F_Gasoline.html

Gasoline Recommendations for Turbo Engines.  [Query]  What octane requirements work best with a turbo? Around here, 90 grade with ethanol is widely available; 92 is more expensive; Will 87, 90 or 92 work?
[Response 1: Bernard]  The B230FT engine is set up for the North American market to run without problems on 87 octane engine (ROZ = MOZ :2). In today's view, that might not have been the wisest decision. Most drivers would appreciate a few horsepower more (maybe on B230ET-level) and rather spend 10 cents a gallon more on gas. Anyway, if knocking is detected on a late model 700 or early 900 car, the Bosch Motronic will retard ignition automatically. However, as with many other cars from other manufacturers, it might very well be that someone experiences knocking when buying no-name 87 octane gasoline. Many of turbo Pilots have therefore decided to run at least 89 octane, many even 91octane gas all the time, myself included.  [Response 2: Phil]  I'm stuck with that ethanol gas also. I can't run 89 so I'm stuck with the more expensive 92. When I can get undiluted gas it makes a noticeable difference in performance. If you can't get anything but the ethanol you'll probably need to use the 92.  [Editor's note: using lower octane will cause retarded timing, lower power and higher engine operating temperatures. Use your own judgement.]

Brake Fluid Performance and Comparisons.  See the Brake Fluid Comparison file for more information.

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