15 replies to this topic

[Tommyboy12]

Hi guys
Got my Megajolt wired up to my 1275 MG Metro engine yesterday. From what ive read it is advisable to get the engine running in 'limp' mode before connecting the MJ unit to the wiring. However Im suffering backfire through the carb. Spark is strong but the carb is running at a base setting at the moment as I stripped it and rebuilt it just before fitting the MJ.
Am I right to think there is too much advance?
Any advice on how to go about rectifying this or is it worth trying to get it running with the MJ unit plugged in and adjust the timing?
The trigger wheel is a machined and welded part I bought off Wilson1330 so it cant be adjusted.
Thanks in advance.

[coopdog]

are the plugs the right way round?

when i started my car sunday it was firing through the carb because the dizzy is 180 degrees out, swaped the leads around and now its fine :)
try that?

[Tommyboy12]

I checked the lead order and it is definitely firing in the right order. However I will give it a try.

[Alex_B]

+1 for checking leads are correct, had the same when I took my leads off to clean bits of the engine bay and put them on 180 degrees out and defo was backfiring through the carb a lot!

[Tommyboy12]

Could it be possible that the ring gear isnt at the correct position on the pulley?

[charie t]

tdc the engine, the missing tooth should be 90 degrees to the sensor

[Tommyboy12]

Checked it today. The leads are firing in the right order and the sensor is 90 degrees before tdc. I played some more but it was still only coughing and backfiring...

[Ethel]

It's wasted spark, both the cylinders fire together. If you can get it to run at all you can use a timing strobe to see what the actual advance is - you could adjust it by adjusting the crank sensor position, but it's easier to just adjust in the MJ software.

[Tommyboy12]

I cant really adjust the position of the crank sensor either. I guess I will just plug in the MJ and adjust it from there.

[Tommyboy12]

Im still trying to get this started. I dont suppose anyone has a map for an MG Metro cam. Its just coughing and spluttering while cranking and not starting.

I suppose I should add:
Plugs are connected in number order as follows: (flywheel) 4-3-2-1 (rad)
There is a permanent live and a good earth.
Fuel is brand new Shell super unleaded (tank was drained and carb emptied).
Car wont run in limp mode or plugged into the MJ.
MJ will speak to the computer fine and I get load readings, however there is no change in RPM gauge while its turning over?

Edited by Tommyboy12, 05 July 2012 - 01:47 PM.

[Tommyboy12]

Another point to add is that the engine is actually getting hot. There is spark and burn. Its just not enough to start it.

[Tommyboy12]

Anybody?

[Gr4h4m]

You need to connect them 1 2 3 4 as its wasted spark. Not in he mini firing order!

So coil 1 to cyl1, coil 2 to cly2 you get the picture

Im still trying to get this started. I dont suppose anyone has a map for an MG Metro cam. Its just coughing and spluttering while cranking and not starting.

I suppose I should add:
Plugs are connected in number order as follows: (flywheel) 4-3-2-1 (rad)
There is a permanent live and a good earth.
Fuel is brand new Shell super unleaded (tank was drained and carb emptied).
Car wont run in limp mode or plugged into the MJ.
MJ will speak to the computer fine and I get load readings, however there is no change in RPM gauge while its turning over?

[racingenglishcars]

Checked it today. The leads are firing in the right order and the sensor is 90 degrees before tdc. I played some more but it was still only coughing and backfiring...

I hope what you mean is that the missing tooth passes the sensor 90 deg before tdc when the engine is turning in the normally rotating direction.
It sounds like (in old standard distributor engines) 180deg out of sync.
Just for kicks, try interchanging leads 1 with 2 and 3 with 4.

[Tommyboy12]

You need to connect them 1 2 3 4 as its wasted spark. Not in he mini firing order!

So coil 1 to cyl1, coil 2 to cly2 you get the picture

That is how they are wired up. As I said. Plugs are connected in number order from rad to flywheel.

I hope what you mean is that the missing tooth passes the sensor 90 deg before tdc when the engine is turning in the normally rotating direction.
It sounds like (in old standard distributor engines) 180deg out of sync.
Just for kicks, try interchanging leads 1 with 2 and 3 with 4.

I tried interchanging the leads and the engine locked while turning it over. I will double check the missing tooth. That would be the only thing I havent checked more than once...