LM7 will not start.
05-12-2011, 09:35 AM
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LM7 will not start. I am new to forum......need help figuring out why my conversion to carberator using Edelbrock intake and Edelbrock MSD ignition will not fire up. I have done all the usual things...contacted both Edelbrock and MSD tech line with no usefull info. I have checked all wiring, grounded box to battery, installed new crank and cam sensor, new plugs and plug wires, tested coils to make sure they are firing. I have compatible crank reluctor (24X). Compression test: 1=135 2=135 3=145 4=135 5=135 6=140 7=145 8=135. I was told that the low compression numbers may be the issue.
05-12-2011, 09:52 AM
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Is the carb bowl filling w/ fuel? Actuate the throttle and watch the accelerator pump nozzles, should shoot a mist of gas during movement of the throttle shaft.
After that is confirmed, whip out your timing light and hook it up to any plug wire. Should pulse the light during cranking...if not then you have no spark.
After fuel and spark are confirmed you're down to ignition timing, assuming you didn't have the cam and/or timing chain out and therefore know the cam is timed properly.
You might re-post this in the Carb section and get much better info, you're in the Internal Engine section where it's all cams/pistons/etc.
After that is confirmed, whip out your timing light and hook it up to any plug wire. Should pulse the light during cranking...if not then you have no spark.
After fuel and spark are confirmed you're down to ignition timing, assuming you didn't have the cam and/or timing chain out and therefore know the cam is timed properly.
You might re-post this in the Carb section and get much better info, you're in the Internal Engine section where it's all cams/pistons/etc.
05-12-2011, 11:43 AM
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LM7 will not fire Thanks for reply. There is 6lb presure at carb and fuel is being fed into carb when trottle is pressed. I have all coils firing, I attached and grounded a spark plug to each coil and they are all firing. Carb mixture screws are turned out three full turns. The engine backfires thru the carb. Currently just have headers not connected to exhaust. Just did a wet compression test all cylinders are between 180 to 190 psi.
05-16-2011, 02:24 AM
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Hello , You said that You have crank trigger ignition , is that correct ? So no distributor ? If You still have a distributor then the ign timing is 180deg off . Pull up distributor and turn rotor 180deg and that should get it online . If no distributor maybe there's a crank learn procedure . Good luck
