Thanks Blokes for your input. What you are saying ties in somewhat with my theory..... There is a small amount of wear on the needles so I have been wondering if the jets are "spurting" rather than evenly atomising. The heavier droplets would tend to make it to the rear cylinder rather than the front.
Rob Rob Thompson 0429 493828 From: [email protected] To: [email protected] Date: Thu, 5 Feb 2015 04:09:59 +1100 Subject: RE: [DOG mailing list] Mixture mystery... All, The Jabaru 6 cylinder was/is having the same trouble ( single common inlet manifold of unsophisticated design), to the extent that the CHT difference between no 1 and no 6 was dangerous to the life of the engine. I think they (Jabaru) have fixed the problem. My friend who had the earlier engine installed, tried may different fixes, which included cyclones, turbulence baffles, and directors (my terminology) or vanes channeling the air. This was both before the carby and after. As far as I can guesstimate the heavier fuel droplets cannot turn the corner to no 1as well as the smaller droplets or vaporized fuel air mix. Thus the heavier droplets go to the end of the tube where they can only go to the last cylinder. Thus the fix or director that John is talking about may well be the answer. My friend persisted and obtained a reasonable even spread of CHT or Combustion, which will be evident on the plugs. I think from memory it was a director or vane turbulator just in front of the carby. Regards Bob Wilson From: [email protected] [mailto:[email protected]] On Behalf Of John Callahan Sent: Wednesday, 4 February 2015 10:22 PM To: [email protected] Subject: Re: [DOG mailing list] Mixture mystery... I have information somewhere about the modification Limbach did many years ago to stop uneven distribution in the inlet manifolds. Some sort of baffle was used to combat pulsating. Will try to find it tomorrow. John. On 4 February 2015 at 21:29, Ian Mc Phee <[email protected]> wrote: I think I read somewhere there is a new inlet manifold for Limbach L2000 which gives better distribution between front and back cylinders. I am wondering if Limbach are putting something in the manifold to improve the air flow and if we could modify same.? Try taking samples of various fuels and do an eyes closed test with various people. The shell 98 is always different with a sort of turps smell. BP98 just smells like fuel. People are picking the Shell 98 first time every time. I should tell all I have 2 used carbs from L2000 ex G109 + inlet manifold. I also have an exhaust engine pipes from a Pusher Limbach & could be cut and modified for use on our installations. I have plaster of parris moulds for aircraft welder to make up engine pipes. To meet the "repair exhaust requirement" he must use a flange from the old exhaust and rest is new. There is more parts thete so will go through them some time. I guess nobody has found my yellow mould for the suck out for H36 in one of their clean-ups? Ian m Ian m On 04/02/2015 7:32 PM, "Rob Thompson" <[email protected]> wrote: G'day all, We have a situation that I haven't encountered before on our L2000. The rear plug on the right side is very "fluffy" (not oily) black but the front one is perfect colour. But they run off the same Carb! I assumed it must be a leak in the head to manifold gasket so I replaced it with some good gasket sealant and it is still the same. Now the same thing is happening on the left side. I have always experienced that plugs running off the same carb look the same. I have just reset the carb needles to the standard position after removing heads and refacing valves. Any ideas? Rob Rob Thompson 0429 493828 No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.5645 / Virus Database: 4281/9055 - Release Date: 02/04/15
