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    Tim Wilson

    Hi, folks: as some of you might know, l’ve been wrestling for 4 months with the problem of engine dying after about 3 mls of running, every time l take the Special out. Ater testing many variables, l’ve finally ruled out fuelling and electrics. Last weekend l took the slab-type fuel tank off the back and drained it. I duly discovered a blockage of fine particles in the outlet pipe junction at the tank bottom. This debris comprised v. small rust specks and similar-size silver particles, all less than 1mm in size. They weren’t, it seems, entirely stopping fuel flow, but drastically reducing the volume of fuel which the new Facet pump was able to put thru. I extended a magnet down into the tank bottom, and drew up more debris. I now suspect that ethanol is breaking down silver solder in joints and old repairs to the tank. So l’m ultimately prepared to have the tank comprehensively rebuilt by a specialist, should the problem persist. First tho, l have to test-run the Special to see if my draining and flushing has resolved the matter. Now, Question: do you think that a magnet(s) in the tank, positioned near the fuel outlet, might be an extra help in keeping the fuel runs clear of future debris? Or might a magnet cause other, unforeseen snags?  Thoughts/advice would be much appreciated.  Tim.



    If the tank appears in otherwise sound condition I suggest you take it out, flush it and clean with Frosts tank flush then coat it internally with their tank sealing liquid. It should prevent further corrosion and obviate the need to put your magnet in. I would also suggest a good fuel filter near the tank outlet and at the carb end. Cheaper than a new tank.


    david Moseley

    Tim I suggest that you buy a length of rubber petrol line Drill a hole in the top of an old petrol can fill it with petrol (if you have any) shove the pipe in the hole and connect the other end to the inlet of your fuel pump in place of the feed from your tank. Providing you can find somewhere to put the can in the car you can drive it and test whether the fuel tank  is the problem.

    The rule of thumb is if you think its a fuel problem its electrical I you think its electrical then its fuel.

    I see your post about E10 petrol Would be a good topic to discuss at the next zoom session Are there any additives that can be put in E10 to make it compatible.


    Ron Dowle

    Tim, Tank flush and then seal is a good way to go. We have saved many a vintage motorcycle tank over the last few years. Never done a car tank so you may have to look at ways to protect the tank outlet and tank vent pipe locations from getting blocked with the sealant.   Ron

    Ben Stevens

    I can’t see the harm in adding a magnet.  I’d have done that if I’d thought of it – I’ve got a brilliant magnet I can turn on and off for picking up all the swarf / angle grinding mess from the floor.

    Only problem I can foresee with a magnet is getting the filings out.

    For what it’s worth, Jim Turnbull recommended against coating the inside of my tank, said it was better to not put anything else in there that could cause issues in future.

    Tim Wilson

    <p style=”text-align: left;”>Thanks for all your words of wisdom, chaps; really helpful prompts. First, l am fairly certain that my tank is from an Allard – perhaps a P1 or M-type – so l want to keep it – and to keep it as original as poss. However, one can see that it has been hacked about in the past. Inside, apart from superficial rust, it looks OK. The problem in POR 15-ing it might be that there is at least 1 huge internal baffle (possibly 2), which could militate against a thorough, even coating of sealant. And l hear what you quote from Jim Turnbull, Ben; years ago l did slosh my TR3 tank with a proprietary sealant, which subsequently (2014) failed during a Le Mans jaunt and resulted in an AA ride back from Ypres and having to renew the tank. Mel, l do have a filter as an integral part of the Facet pump (l’ve checked it’s clear) and a further filter just downstream of the pressure regulate on the scuttle. David: great minds think alike! Yesterday I jury-rigged just what you describe and would’ve tried it out today, had it not been pouring with rain. Ron: while l have flushed the tank with water (and dried it out completely) l think l might now use a chemical flush to consolidate the process. I will keep you all posted; if you’ve further thoughts, please add to the mix! Tim.</p>

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