Sudden loss of power 2lt cu Aircooled.

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sarran1955
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Re: Sudden loss of power 2lt cu Aircooled.

Post by sarran1955 »

Hello,

Use the model as shown, it is 'incompatible' because it is a SVDA not a DVDA.

However, as you will be timing at 8.5 degrees BTDC (SVDA), and not 5degrees ATDC (DVDA), taking the vacuum signal from either the lhs carb or even the balance tube.

I will be doing another video on this topic soon.

Cordialement,

:ok
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paperhouselad
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Re: Sudden loss of power 2lt cu Aircooled.

Post by paperhouselad »

Thanks sarran, on order, think i understand it more now, getting my head round it.

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Re: Sudden loss of power 2lt cu Aircooled.

Post by paperhouselad »

About done it now, just wondered which other of the original wires are to be left connected ie to the coil, presume the brown one under the old distributor is redundant, thanks in advance.

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sarran1955
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Re: Sudden loss of power 2lt cu Aircooled.

Post by sarran1955 »

Hello,

You will need the +ve feed wire from the big black plastic box inner left wing, to the + on the new coil, then the feed to the carbs on the same terminal.

The red lead from the dizzy goes to the + terminal on the coil

The black lead from the dizzy goes to the - terminal on the coil.

So you will need a proper 3, or even 4 lug terminal on the + of the coil.

and a 2 lug on the -terminal would be good.

If you have the original old Bosch coil, the terminal lugs can be unbolted, and in the bottom of the dizzy delivery box there are more lugs and nuts.

Now for the good news... :)

The rest goes in the bin, loom,amplifier, idle stabiliser.

Use a timing light to get the 8 and a bit BTDC,

My rough setting on the video needed a slight clockwise tweak to the dizzy on start up.

Use quality vacuum hose flexibles.

The idle speed should not alter much, it is controlled by the brass air horn screw on the lhs carb.

I must get these new videos done... :roll:

Hope this helps..

Cordialement,

:ok
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paperhouselad
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Re: Sudden loss of power 2lt cu Aircooled.

Post by paperhouselad »

Great stuff sarran, ùnderstand now, already swopped the old terminal lugs over onto the new coil, fire it up tomorrow and give it some timing light. Again many thanks, :ok sarran.

paperhouselad
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Re: Sudden loss of power 2lt cu Aircooled.

Post by paperhouselad »

must be doing something wrong, had three attempts starting from scratch at timing as per the video and will barely start but if I twist the distributor, I think clockwise ? it runs pretty good but don't have a timing mark to go off with my strobe for more accuracy. sorry saran.

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sarran1955
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Re: Sudden loss of power 2lt cu Aircooled.

Post by sarran1955 »

Hello,

The timing notch really is on there, on the inner flange of the pulley... :roll:

Mark it up with Tippex.

No need to apologize.. :)

Even without a strobe, once the engine is running on a slightly speeded tick over, then you will find the 'sweet spot' by rotating the dizzy clock wise starting at the stumble point on the rhs, through max speed, back to the lhs stumble point..between the 2 is not far off..

Don't forget to re tighten the pinch bolt.. :wink:

You'll be setting it again once everything has settled down.

Air Cooled Bliss.. 8)

Cordialement,

:ok
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paperhouselad
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Re: Sudden loss of power 2lt cu Aircooled.

Post by paperhouselad »

All sorted now running better than ever, turns out it was a bent valve not seating properly, and then the valvespring broke causing the misfire / powerloss. Anyway new head coupled with powerspark ignition she now purrs along. Many thanks to all who gave input especially sarran 55 whos videos helped no end. Cheers.

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