Fuel system cleaner

[Blueadventures]

Has any one run a fuel system cleaner through their tanks and engines. I have a Rotax 912 ULS and run ‘Liqui Moly’ in my diesel patrol to give the system, pump and injectors to give a clean twice a year, also worked on my Hilux diesel.  Thinking it might be ok to run the petrol additive through the Nynja’s tank or the collector tank to give the carby internals a clean out of any buildup of deposits.  Any experience comments appreciated.

[skippydiesel]

I would not - you dont know what the additive/cleaner/conditioner actually is (chemical constituents & ratios) and therefor its compatibility with the fuel system is unknown.

 

Further - unless your engine is infrequently run and stale fuel is likely, I doubt any real/cost effective benefit will result from using a fuel additive. 

 

Like you I use a diesel additive/conditioner, at double the minimum rate - about every 4-5 tank fills (approximately 3 - 4,000 kms) l. No idea if its doing anything really (makes me feel good) I hope for a longer service life for my Ford Ranger 3.2L, common rail injection system.

 

It may interest you: I keep a record of all fuel used/added, what the main activity was (towing a large/small trailer, long distance free way trip, etc) and the kms. So far, I am unable to see any improvement in km/Litre for the Ranger. I have a 1985, Daihatsu Rocky2.8  turbo diesel - old style indirect injection - the same fuel additive resulted in a small increase in fuel consumption. 

[spacesailor]

Were do you put the 'liqui Moly ' 

In the oil or the fuel tank !.

spacesailor

[Blueadventures]

55 minutes ago, spacesailor said:

Were do you put the 'liqui Moly ' 

In the oil or the fuel tank !.

spacesailor

In fuel.

[walrus]

Don’t use anything unless it’s approved by Rotax or you are now a test pilot. You have no idea what the effect of this cleaner will be. For example what if it “works” and liberates a mass of dirt and decayed contaminants into your fuel system - when you are at 6000ft over tiger country?

[cscotthendry]

What Walrus said, or worse, what happens if a lump is dislodged at 200 feet over trees at the end of a runway on takeoff.

[spacesailor]

"Were do you put the 'liqui Moly ' 

In the oil or the fuel tank !."

There was a molybdenum (spelling  ) that was an oil additive, if l remember a black powder.

After adding & using, do you wash it all out with a dose of clean fuel !.

spacesailor

[skippydiesel]

12 hours ago, walrus said:

Don’t use anything unless it’s approved by Rotax or you are now a test pilot. You have no idea what the effect of this cleaner will be. For example what if it “works” and liberates a mass of dirt and decayed contaminants into your fuel system - when you are at 6000ft over tiger country?

I agree with the advise not to use - but not the reasoning - Highly unlikely scenario!

[facthunter]

There was also a colloidal Graphite additive for engine oil. Todays best filters would probably separate these additives out and they would tend to centrifuge out into the oilways. MOS2 coating is used on new  camshafts often. (NOT when rollers used)  Nev

[onetrack]

Molybdenum Disulphide has been around since WW1 and its superior lubricant properties, particularly under "dry lubrication" conditions, were noted by the 1920's.

You can still readily buy MoS2 in powder form and in oil-based formulas as a lubricant additive. A number greases used on construction equipment contain MoS2, as it continues to lubricate when the grease is getting hammered out of pins and bushings, or dust, dirt and mud are destroying the contained oil and soaps lubricating abilities. Liebherr make a special semi-fluid lubricant for their excavator gearboxes, that is about 50% MoS2.

 

A bloke used to sell a product called "Krause" in the Modern Motor magazine for decades, from the 1950's to the 1990's, for fixing whines in gearboxes and diffs. It was simply concentrated MoS2 in a heavy oil base.

It did work to a certain extent, I can remember buying some to fix a whining Holden diff (Holden diffs were terrors for losing bottom drain plugs on rough roads, and you only found out when the diff started to whine with no oil left in it!)

 

As far as fuel additives go, they're all pretty much based on the same style of additives. Solvents to clean out combustion deposit, combustion-promoting hydrocarbons, such as 1,2,4 trimethylbenzine and naptha hydrocarbons, and lubricant additives such as polybutenes that also prevent deposit buildups in combustion chambers.

A lot of these fuel additive products contain Stoddard solvent, also known as White spirit, and which is used in paint thinners, as a parts cleaning fluid, and in drycleaning fluids. There are also a number of essential oils added to fuel additives, as a large number of essential oils contain volatile hydrocarbons that provide improved fuel burn, and which also act as potent solvents for petroleum and combustion deposits.

 

You would need to have a seriously dirty fuel system for a fuel additive to release deposits that would clog your fuel system. All of the fuel additives are exceptionally pricey (around $30-$60 a litre bottle) and they are used in very small quantities, such as 50 or 100ml to a tankful of fuel. Thus their concentration is pretty low, and their action on deposits is relatively slow, it's not like they would release huge globs of fuel tank deposits in one go - that's if you had major deposits in your fuel tank or fuel system, anyway.

 

Where they do operate, is in removing thin deposits of gums and varnishes in fuel systems, in pumps, and combustion byproducts buildup in combustion chambers themselves.

If you have major combustion chamber deposits, you're well on the way to engine trouble with hotspots and detonation and pre-ignition, anyway. Many older engines throw out small hot particles of combustion deposits, without any major drama.

 

 

Edited June 19, 2021 by onetrack

[walrus]

DO NOT add moly or any other friction modifier to oil if your rotax has a slipper clutch. If you do, your clutch will probably start slipping and require replacement.

 

Sorry to be a wet blanket, but rotax has a service letter on fluids.

 

 

[facthunter]

There are additives that stop bacteria growing in fuel .Jet A1 has such additives, Also you can get some for other  fuels. It's sold for lawn mowers and such things.  Might be worthwhile in antique motorcycles etc

  Colloidal graphite is rarely used except in DRY form for locks etc  but CV joint greases have  the highest %'s of MOS2.   MOS2 is regularly used as a paint on new or reground camshafts without roller followers. Nev

[Paul davenport]

Best to use the 98 fuel if you wanted to keep your fuel system clean as it cleans as you go .  There is a spray in the carby cleaner used by Subaru ( I have used it and it works well ) but if you were using the 98 that probably wouldn’t be needed

[jackc]

17 hours ago, onetrack said:

 

If you have major combustion chamber deposits, you're well on the way to engine trouble with hotspots and detonation and pre-ignition, anyway. Many older engines throw out small hot particles of combustion deposits, without any major drama.

 

 

Water injection would solve that problem, but you would need a precise, reliable method of doing it

https://en.wikipedia.org/wiki/Water_injection_(engine)

 

[skippydiesel]

We are all susceptible to the magic quick fix "mechanic in a bottle" products. They promise much and deliver little. Over the many many years I have been playing with machinery, I have seen so many of these miracle products come & go.

 

I get "hooked"  infrequently  but I am ashamed to say I take the bait all too often.

 

I have yet to find  one of these products that delivers a cost effective benefit  ie there may be a benefit but the cost out ways the result . The one exception is the appropriate use of Molybdenum Disulphide.

 

A tangential benefit may also be that people who lean towards these products are often anal about servicing/maintenance and so their equipment tends towards longer in service life & reliability.

[facthunter]

Quite a  few actually do harm. The only way to clean a motor internally is to dismantle it and use the right chemicals or other processes, in the case of rust scale, Metals like aluminium and magnesium alloys need special attention. .All oil gallery and cooling system welch  plugs should be removed and oilways physically cleaned out. Magnesium needs special surface treatment (chromic acid). to prevent corrosion of the surfaces.  Nev   

[spacesailor]

The one proct that I consider good is ' Lithium ' grease n & spray, when you havr the need to lube plastics it works wonders.

spacesailor

[Blueadventures]

Thanks for all comments.  I am not going to use in my fuel system.

 

For info the ‘Liqui Moly’ brand diesel injector cleaner worked well in my Hilux 3 litre diesel when it was running rough.  I had planned to pull the injectors a replace the tips and ran two cans of the cleaner in low volume tank contents and idle when to smooth.  Every twelve months I put a can in the tank at low volume and run it through.  Seems to continue with good results.  Just hoping to always remove light deposits in the system to ensure particularly the inject nozzles are spraying the diesel within spec. Cheers.

Edited June 20, 2021 by Blueadventures

[skippydiesel]

3 hours ago, spacesailor said:

The one proct that I consider good is ' Lithium ' grease n & spray, when you havr the need to lube plastics it works wonders.

spacesailor

High quality silicon is better, longer lasting (persistent) and less prone to attracting dust - I have used CRC Automotive Silicon (Red can) for a squillion years. It expensive but a little goes a long long way.

 

I also use Lithium grease  - from a spray can - mainly on garden tools, automotive door mechanisms/hinges and also as a grease (out of a tube) for very specific lubrication of components where specified.

[spacesailor]

Agree  Silly cone is good, can you get it as a grease thou.

spacesailor

[skippydiesel]

14 hours ago, spacesailor said:

Agree  Silly cone is good, can you get it as a grease thou.

spacesailor

Yes you can - very expensive  for the good stuff - I use Molykote 111 - a tube usually lasts me 2 years

 

[spacesailor]

Molycoat !.

That rings a bell for ' antyseize ' .

long time ago, SO l will give looking through my garage away. 

spacesailor

[skippydiesel]

Molycoat is owned by Dow Corning - they have a staggering range of products

[facthunter]

So has our local Pub. Nev