Cutting out under load

Maestro, SEI-V
mbmm350s
Posts: 666
Joined: 22 Jun 2018 10:18
Location: Reading UK
Location: Berkshire UK

Re: Cutting out under load

Post by mbmm350s »

Is your Avo so old it has only 1000, 10000 and 100000 resistance ranges like a 47 !!!! - check on the 1000 ohm scale
Treebod
Posts: 18
Joined: 08 Jun 2017 19:43
Location: Hereford

Re: Cutting out under load

Post by Treebod »

Update,had it running again today ,when it got hot it was reluctant to rev when opened up and kept fluffing,then it stopped dead, checked for a spark,none on either cylinder,this time still no spark even when cold, its official ,its dead! guess I will be taking the Guzzi to Cadwell.
Treebod
Posts: 18
Joined: 08 Jun 2017 19:43
Location: Hereford

Re: Cutting out under load

Post by Treebod »

Hello,yes it is old, ex army- 1950's !,but checked it with a modern multi meter at x1k it read off the scale-it only goes up to 250,so I am pretty sure the stator is ok, unless you have other ideas,i now favour the pick up as the guilty party.
Steve Brown
Posts: 1390
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Re: Cutting out under load

Post by Steve Brown »

Treebod wrote:Hello,yes it is old, ex army- 1950's !,but checked it with a modern multi meter at x1k it read off the scale-it only goes up to 250,so I am pretty sure the stator is ok, unless you have other ideas,i now favour the pick up as the guilty party.
Not familiar with your meter but surely you only need to use a 0 to 300 or 500 ohm scale? If you are finding too high a resistance then that would suggest a knackered coil too. It's when you mention 1k I'm puzzled but that isn't too difficult to do either.
All donations to the rest home for old Camels, Leicestershire.
mbmm350s
Posts: 666
Joined: 22 Jun 2018 10:18
Location: Reading UK
Location: Berkshire UK

Re: Cutting out under load

Post by mbmm350s »

Hi,
Hello,yes it is old, ex army- 1950's !,but checked it with a modern multi meter at x1k it read off the scale-it only goes up to 250,so I am pretty sure the stator is ok, unless you have other ideas,i now favour the pick up as the guilty party.
I have a 47a ( 1940s admiralty version) it has a 1K range, try on that. As Steve says a very high resistance would also indicate a faulty coil, it should be between say 200 and 300 ohms. We are thinking the generator winding has died!
An alternative is it could be that one transducer is faulty (due to shorted thyristor) and it is effectively shorting the generator (green wire). May be try to see if either transducer can fire on its own by disconnection of the other one's green wire
Its rare for a pickup failure to fail both cylinders, and it would most likely in that case that its earth is broken/detached. worth a look for sure.
If you can trailer to Cadwell there might be someone who could help with parts swaps to diagnose it.

Mark
Treebod
Posts: 18
Joined: 08 Jun 2017 19:43
Location: Hereford

Re: Cutting out under load

Post by Treebod »

Hello , thank you I will certainly try what you suggest & if I get nowhere I may take you up on your offer and bring it up anyway,i will prep and bring the Guzzi up as well just in case. As an aside which replacement ignition system would you recommend if I were to consider replacing the standard set up? Thanks again.
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