13 replies to this topic

[johnR]

I'm struggling to start my uprated 1275 engine. The plugs all show sparks, the timing seems right (checked several times) but it won't fire even though there is petrol on the plugs and vapour coming out of the exhaust. I'm wondering if the coil is not up to the job - Lucas gold sport one?

[DeadSquare]

It sounds as though it is flooded..

 

Take the plugs out over night and tomorrow try filling the engine with as much boiling / hot water as you can and warming the carb with a hair dryer and replacing the plugs that you have just heated with a blow torch before trying to start it with no choke.

[johnR]

OK - I'll try that - just checked the coil with a multi-meter and it's showing 4 ohms across the output so presume no problem with that.

[NZMini1275]

Did you set the 123 up at Tdc ?
What values have you put in map

[KernowCooper]

Those Lucas Gold coils are a source of trouble and if its not a old Gold Coil replace it to avoid problems down the road, do the makers of the 123 distributor not say what coils to use?

[croc7]

I found that you have to follow the instructions, PARTICULARLY to leave the black wire (neg ground) unconnected when setting static timing using the LED in the 123, Once that is done, tighten the 123, then connect the black wire to the coil. Give that a try.

[johnR]

I found that you have to follow the instructions, PARTICULARLY to leave the black wire (neg ground) unconnected when setting static timing using the LED in the 123, Once that is done, tighten the 123, then connect the black wire to the coil. Give that a try.

Good point! - looking back over the instructions I may have set the dizzy up before static timing , so the dizzy may be working against me. 

I'll re-set it from scratch.

[johnR]

Did you set the 123 up at Tdc ?
What values have you put in map

Possibly not - I haven't changed the default curve. I'll re-set the dizzy after static timing. thanks. 

[johnR]

Investigation seems to point to the carb manifold gasket not sealing - it's the large port type but the inlet holes in it are too big leaving a very minimal contact area with the manifold. There's good suction at the head but none at the carb mouths with them in place.

[mk1leg]

Do as Instructions say and use a flame thrower coil as recommended by 123 onse tdc is found remove rocker cover and watch valve 7 and just as you see it move thats TDC remove old Dizzy and install new 123 remove red cap connect red lead to coil +tive and twist dizzy body anticlockwise untill you see a green LED light up through a hole in alloy plate also turn rotor arm clockwise to remove slack once you see the led light up Clamp tight refit cap connect black to -tive and select appropriate curve to suit engine spec I found the works setting best curve

[johnR]

The instructions say turn body until the green LED 'just' lights - did you take that to be just the edge of the LED or the LED fully visible?

[johnR]

Do as Instructions say and use a flame thrower coil as recommended by 123 onse tdc is found remove rocker cover and watch valve 7 and just as you see it move thats TDC remove old Dizzy and install new 123 remove red cap connect red lead to coil +tive and twist dizzy body anticlockwise untill you see a green LED light up through a hole in alloy plate also turn rotor arm clockwise to remove slack once you see the led light up Clamp tight refit cap connect black to -tive and select appropriate curve to suit engine spec I found the works setting best curve

My coil seems to be one of the few Lucas Gold Sport ones that's OK - showing 4 ohms which is more than the Bosch Blue that 123 sell. As I mention above, my biggest issue is lack of suction through the carbs so I need to address that first. Where did you find the works curve you mention - presumably you input the curve yourself?

[ansmania]

So how did it go with your 123 bluetooth?

I’ve just ordered mine and am curious how to set it up. Did it come with any preset curves or you gotta manually set it up on your own?

[johnR]

So how did it go with your 123 bluetooth?

I’ve just ordered mine and am curious how to set it up. Did it come with any preset curves or you gotta manually set it up on your own?

It comes with a pre-set curve that should be fine until you get it on a rolling road.  I haven't really had the opportunity to really get any use out of mine as the crank shells and bigends went after only 100 miles. trying to track down the problem now.

Being able to monitor the engine on a phone is great though, as is the ability to lock it. Let me know how you get on with yours.