Seems a bit flat??

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Velocemitch
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Seems a bit flat??

Post by Velocemitch »

I've just about finished restoring my Minor now and I've been out for a few test runs. There's something not quite right about the way the engine is running.

Previously I remember the throttle response was really sharp, just a quick blip and it would rev, it's not like that now it takes a few seconds before it picks up.

It seems to pull reasonable well though, maybe it lacks power... I'm used to cars with five times the power or more so that could be me, but the throttle response certainly isn't right.

I have an inkling I know what this is, but before I mention it perhaps somebody will confirm it so I haven't put words in the their mouth so to speak. :)

As background I have recently changed all the easy stuff, Coil, Plugs, Leads, Points condensor etc. I also changed the Head gasket as that blew when my daughter put the starting handle through the rad! :roll: . All that was to cure other issues though, the throttle response was always pretty good up untill now.
MarkyB
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Post by MarkyB »

Check the vacuum advance is working.
bmcecosse
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Post by bmcecosse »

Piston clear to lift and fall in the carb ? Does it respond better with some choke out? If so - it's set too weak!
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Velocemitch
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Post by Velocemitch »

MarkyB wrote:Check the vacuum advance is working.
Bingo, thats what I was thinking.

How can I tell though?, I can feel it sucking if I take it off at the dizzy end, but it makes not a jot of differance too how it runs, if it's on or off,, which can't be right.

I don't think having the choke out helps much but I might try that. How can I tell if the piston is clear to rise and fall?.
bmcecosse
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Post by bmcecosse »

Lift it with a finger - and then - let it fall!
Yes - failed vacuum unit will make for a 'flat' engine too - test it by sucking the pipe to the dizzy - and watch the base plate - it should move!
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