Hints and Tips - Fuel Catalysts

From: Geoff Holmes
cc: british-cars-pre-war
Subject: Questionable fuel catalyst
Date: Sun, 28 Mar 1999

I received in the post yesterday a leaflet extolling the many virtues of something called "System4" (sic). It is "a fuel catalyst made from an amalgam of metals uniquely bonded", and is, according to the blurb, just too good to be true, its main claim being that of "converting" elderly engines to use unleaded without damage. Installation consists of chucking a sachet of pellets into the petrol tank (good for 250,000 miles), and the product comes with endorsements, a money back guarantee *and* discounts. As an engineer and a sceptic, I ask why haven't I heard of it before, and at UKP45, why haven't we all got one (no mention of the U.S. anywhere)? Bargepoles tend to spring to mind.
Any comments welcomed, especially from technical folks.


Date: Sat, 27 Mar 1999
From: M. Frankford
To: Geoff Holmes
Subject: Re: Questionable fuel catalyst

Lead was removed from gasoline here in the early 80's. There was a lot of snake oil being sold around that time. I talked with a shop who makes a living building race engines as well as rebuilding old engines. He said that he has not seen any problems with valve erosion except in marine engines and NASCAR engines. Those engines are held at high loads at high rpms for long periods of time. He said that the engine wear is considerably less with unleaded gasoline. Drive passively and keep it under a 100mph and there should be no problems with unleaded fuel was his advice.

For almost two decades now I've used unleaded gas in my Rileys, I'm amazed at how clean the spark plugs remain. The only real problems are with octane. Gone are the days of 100 octane. Current fuels ping with 11:1 CR engines. Therefore, I used 8.3:1 pistons when rebuilding my 1500cc Riley engine.


From: Graham Orme-Bannister
Date: Sun, 28 Mar 1999
Subject: RE: QUESTIONABLE FUEL CATALYST

There are several so called "catalysts" on the market making all sorts of claims about improved fuel consumption, reduced emissions, protection against valve seat recession, octane enhancement, reduced particulates from diesel engines, etc., etc.

They are mostly based on metallic tin and hark back to poor aviation fuels during WW2. The one thing they all have in common is complete lack of any data acceptable to the technical community. There is masses of data presented but most of is of the "I have used it for a year and had no problems" variety. The best known product, Broquet, was told by the (British) Advertising Standards Authority to stop making claims it could not substantiate, but it does not seem to have had much effect. The bottom line is that, if such a simple technique had even one tenth of the effect that the suppliers claim, then the engine makers and fuel companies would be on board, but they are not. There is no theoretical basis for the claims, even though catalysis is a perfectly respectable chemical technique in industry.

In the absence of any acceptable comparative data, the Federation of British Historic Vehicle Clubs (FBHVC) have contracted the Motor Industry Research Association (MIRA) to run a 70 hr bench engine test based on the Rover "A" Series engine to evaluate products and devices to protect against valve seat recession using unleaded gasoline. The testing is supported by the Rover Group in the supply of new "old specification" cylinder heads. The test has fairly good discrimination showing recession of 0.001mm using leaded gasoline and 1.00mm using premium unleaded gasoline.

Forty suppliers of products and services were invited to submit to the test, twelve accepted. Suppliers pay for the test and the results are their property. The FBHVC will endorse those products considered to give "adequate" protection. Of the twelve products tested, four were considered adequate and were those four listed by Dick Morbey in his note. The results were assessed by an independent technical assessor and have been accepted by the Royal Automobile Club (RAC). The other side of the coin is that eight products failed, but we do not know which eight. None of the products gave protection as good as lead, and the FBHVC endorsement exludes "racing or any other exceptionally arduous uses". It also advises against mixing additives.

A further series of tests may be run if sufficient suppliers submit their products. It is also hoped that Lead Replacement Petrol (LRP) will be tested if and when such a product appears. It has been promised by the end of the year but the British Standards Institute has yet to publish an accepted Standard.

The FBHVC Newsletter can be read on web site; www.come.to/Motordata.

Graham Orme-Bannister
Alresford, Hampshire, UK


From: Mike Robson
To: Geoff Holmes
Subject: Re: Questionable fuel catalyst
Date: Sun, 28 Mar 1999

Sounds like nonsense to me Geoff.....a scheme to collect the odd forty five quid!
I'm not especially technical but having lived in the US for many years I have already gone through the "lead withdrawal" syndrome that the UK is facing - its a bit like your odometer rolling back to zero......A certain amount of trepidation but..... Nothing happens Any engine that has been running on leaded fuel for as long as our cars has built up a sufficient coating to run just fine on unleaded fuel without any type of modification and the only thing to remember is to use hardened valves and seats the next time you need to rebuild - which won't be any earlier with unleaded than it would have been on the old stuff I have put 12000 a year on one of my MGs, (a 70 GT) for the last 4 years - all with unleaded and the engine is still completely original. My RMF was resurrected a year ago after standing since the early 70s and fired right up on unleaded after little more than rubber replacement and continues to run just fine some 2500 miles later Save your 45 quid and buy your club a round at the next meeting!

mike robson
53 RMF
CT USA


From: Graham Orme-Bannister
Date: Mon, 29 Mar 1999
Subject: Re: QUESTIONABLE FUEL CATALYST

Neil Sherry referred to lead replacement additives and turbocharger corrosion. There have been problems reported using sodium technology additives causing corrosion of exhaust valves and turbochargers on Volvo and Saab cars in Sweden. The (British) Retail Motor Industry Federation presented a paper on this at a recent London Conference but so far I have been unable to get a copy.

The four products recently endorsed by the FBHVC by chance represent four different additive technologies, sodium, potassium, phosphorus and manganese. It is not clear which sodium technology products are implicated in the Swedish case, but it seems reasonable to ask any supplier of sodium based products some pertinent questions before using his products.

Given the warning not to mix additive technologies, one of the things delaying the introduction of Lead Replacement Petrol in the UK is the need to specify the additive technology to be used. It would be unworkable to have different companies supplying LRP which could not be mixed with another companies LRP. Refuelling on a dark wet night would be a nightmare if you could only stop at an XYZ filling station. In the light of what we know it seems unlikely that sodium based technology will be specified for LRP.

Graham Orme-Bannister
Alresford, Hampshire, UK


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