The UK hub for Luscombe Aircraft across Europe 

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Technical Chat Tips and Advice, including flying the Luscombe

Moderator: HTB

 #3132  by Tom
 Sat Dec 27, 2008 12:19 pm
Hi Rob

Nice to hear from you!

Thanks for the advice KB running really well at the moment, so maybe your right, maybe we shouldnt try Mogus!!

Do you think the problems in running could be the needle valve? Did you fit an all metal one?

We did mention to Alan that we may come over to Tibenham in the summer, so might see you then :D



 #3133  by rv8or
 Sat Dec 27, 2008 2:47 pm

I joined this forum purely so that I could let you know what we found when we tried to run on mogas.
I would have hated to see you with another rebuild if I had not mentioned anything.
I think the fuel cost difference at the rates which KB burns fuel makes it a no brainer.

I flew into Templehof from Norfolk in the RV 6 this year and fuel burn averaged out at 6.3 gals/hour.

I hope we see KB this year on our, or your travels.

All the best

 #3148  by Tom
 Tue Dec 30, 2008 12:49 am
Hi Rob

Thanks for the advice, much appreciated.

Hope to see you on our travels :)



 #3211  by GARRY626
 Wed Jan 07, 2009 9:00 pm

 #3217  by Nige
 Thu Jan 08, 2009 9:52 am
You beat me to it Gary! Indeed there is Tom and the LAA paint a cautious picture... :?

 #4717  by Tom
 Thu Feb 18, 2010 9:45 pm
Hi All
We finished all the modifications to KB’s fuel system, new needle valve, hoses etc, at the end of last year, but due to the bad weather, have only recently started flying on Mogas. After about 8 hours now I can report KB is running really well on the stuff. We use the left tank for Avgas and the right for Mogas, take off and landing we use avgas, and when settled into the cruse switch to Mogas. There seems to be no difference on mogas and fuel consumption and performance are the same. I checked the plugs today, they where a light brown colour with very little lead deposits. The only difference I have noticed is that the exhausts are sootier on mogas. We will have to see what the warmer weather brings.

Many thanks to everyone for their advice, especially Pete Bush, who is always there with advice and support when ever needed! More Beer coming your way this summer Pete :cheers2:
 #4719  by Nige
 Fri Feb 19, 2010 9:30 am
Very interested to see how it all goes with KB Tom. Hope it all works out.

Talking about fuel, can anyone help me with my 'mild' dilemma regarding fuel selection;Both, left or right?? or have confused everyone with my previous thread again?? 'Andair Fuel valves'

Incidently, I only run on Avgas even though I've done the full conversion, AND the new needle starting leaking!! :? {stopped now}.

Don't we just love aviation eh? :wink:

Good luck all..

 #4720  by Steve Martin
 Fri Feb 19, 2010 3:28 pm
Interesting article in the Luscombe Assoc Mag this month by D. Combes on the "both tanks on" syndrome. His advice is never do it. Always use one then the other. There's some calc's for vent pressure (way over my mental ability!) he uses to confirm his theory.
Having said that, I'm afraid I usually fly with both tanks on. May be I wont in future?
 #4721  by Nige
 Fri Feb 19, 2010 6:00 pm
Just said all that asking for clarity about this on the thread reagrding Andair fuel valves etc! :?

 #5679  by luscombe47
 Sat Nov 20, 2010 8:48 pm
Hi Tom

Been flying a A65 Continental (Champ) for 8 years and the last 10 years a C90 (Luscombe) on Mogass with 0 % problems - old and brand new carburators. True about the more modern Mogass which produce more ugly black greesy stuff. Remember this is low compression engines originnally built for 87 octane so they do fine on 95 octane. Don't mind about the warmer days or height which is also a piont of discussion regards vapour locks :sign3: . I have operated a lot between 5000 - 10 000 ft without any problems. My flying today was on a nice cool morning 23 degree celcuis (will hit a low 17 degrees tonight :shock: )- normally it is 30 :sunny: and above with no problems. Enjoy your "cheap" mogass ! By the way, what is your price currently in the UK ?

Luscome 47
 #5681  by Tom
 Sun Nov 21, 2010 4:36 pm
Hi Luscombe 47

Weve have run KB on Mogas for the last year or so with no problems at all!

Mogas here is about £1.20 per litre and Avgas is about £2.00 per litre, at our local airfield.

Where about are you based?


 #5688  by Robert Lees
 Mon Nov 22, 2010 7:02 pm
Tom wrote:< snip> Avgas is about £2.00 per litre,

£1.58 at my airfield. A quite useful guide on UK avgas prices here.
 #5700  by luscombe47
 Wed Nov 24, 2010 7:02 pm
Hi Tom

With current exchange rates Mogass are about £0.80 per litre and Avgas £1.0 per litre. Nige asked me to do a post about my flying in Malelane, South Africa - will do it under the General section.

Luscombe 47
 #5703  by Nige
 Thu Nov 25, 2010 8:56 am
Thanks '47.D'you pay landing fees over there?

Wow! Grrrreat fuel prices '47!! God, we're ripped off here in Europe!!! :mad: Off to Turweston today, 2 and half hours flying, - best part of £100.00 including landing fees. Not including lunch! :? [-2c at the moment, 9am. :shock: ]

 #6358  by TIJ
 Thu Jun 30, 2011 1:15 pm
Hi All,

I've started running on Mogas but not on the Luscombe. I'm quite wary of ethanol as although the rotax engine is approved, we in the gyro community were left off the CAA's dispensation for the use of fuel containing it. Therefore we have to be extra cautious in these litigious times. I therefore bought an ethanol test kit from Airworlduk LTD.

Here's the link. ... 1352-p.asp

I can't vouch for it's accuracy, but so far I've managed to buy fuel wisely. I'm using BP Ultimate 97 as I'm on a turbo, and so far I've not seen any alcohol indication, at least not from my local BP garage. I'll test any other brands as I use them and let you know as and when, however it will only be the super unleaded that I'll be using. Surprisingly this is at odds wi the recent article in Light Aviation which stated that BP were one of the majors that did put ethanol in their supr unleaded fuels.

Ho hum.