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I added the turbo upgrade and have been unable to start the engine.
I verified the presence and timing of the coil ignition system. The magnetrons are turned on while cranking.
The heads have been rebuilt; compression is good.
Fuel flow to the Aerocarb is good; #3 needle installed. Fuel drips out when I advance the throttle & mixture.
However, after much cranking, there is no firing and no sign of gas on the spark plugs or even in the intake manifold directly above the Aerocarb.

Any ideas will be appreciated....
Steve Craigle

My first thought is ignition…. AeroInjectors may have issues when running but never heard of or seen one not start, especially if you have fuel dripping out of it. Now, I'm assuming you are using 100LL and not old MOGAS…..

How did you verify the presence of and timing of the ignition? I read on one of your earlier posts, you were querying the 10 deg BTDC timing. This is the system used for starting and if it's way off, that could be the problem. I left mine at 28 BTDC and have no issues. (Note: I did try 10 BTDC and didn't like it.) Check Secondary ignition timing again and keep us posted. Good Luck.

Coil ignition timing ~ 20°BTDC
Fuel a mix of new MOGAS & 100LL; I may drain the tank and go for 100% 100LL.
I may also spray some ether into the intake to get some noise out of the engine.

May I also suggest you check for induction system leaks that may be preventing the engine from developing suction down to the AeroInjector to grab the fuel air mixture.

Jake

Forgot to mention initially: I took the Aerocarb off and cranked the engine with my hand over the intake tube. Sucking up a storm...

Since you have said it is sucking with your hand over the intake manifold, try as you said a bit of starting fluid. But be careful, dont get in the way if it belches back on you. also, maybe its way beyond floded. the plugs you pulled were the top or bottom plugs? look at both. Raw fuel should settle on the bottom plug, and maybe not show up on the top? Just my thoughts from days gone by! :)

Not to nag, but if you confirmed you had spark on secondary, it could be 180 degrees out, or coil wiring switched between triggers…. again, good luck. And as a side note, WD-40 works great as a starter fluid and is a little safer…..

Yes, I checked all the secondary trigger-to-coil wiring early on. All OK there. And yes, I was checking the lower plugs for fuel.
I just found the # 3 needle to be severely toward the lean position to the extent that the needle carrier was acting as the idle stop for the slide. Just finished fixing all that and will give it another try tomorrow. I may still use the manifold pressure port to squirt a little 'go juice' in the intake.
Thanks, everyone for your comments & suggestions!
Steve Craigle

Success!
First run today. Very smooth & quiet (turbo acting as a muffler?) Not so smooth on magnetrons only, but that may go away with more rpm. Also have some mixture control calibration issues; couldn't shut it off with same. I used some 100LL for starting fluid in the MAP pressure port, but later stopped & restarted without any prime. I think the problem all along was the poorly adjusted taper needle in the Aerocarb.
I'll be shopping tomorrow for a VDO tach that operates from the AC output from the alternator.

1X99 wrote:I'll be shopping tomorrow for a VDO tach that operates from the AC output from the alternator.

Just FYI,
I've been having a hell of a time trying to get a good enough signal from one of my alternator outputs to use on my MGL E1 (the old version with no adjustment possibilities). Tried resistors in series, ballast resistors, capacitors, ... nothing works.
It gives my good readings for the first 20-30 seconds, then it's like the signal is becoming unstable and dropping away. RPM readings go lower and lower to almost nothing...
I've tried to get a signal from my magneto P-lead as well, although more stable it seems to under indicate throughout the range, probably not a good clean signal either.

Next thing I'm going to try is using an optocoupler to generate a clean pulse off BOTH AC outputs from the alternator when crossing 0, this is a much more tidy solution and should give me nice clean signal. It is a common solution to this kind of problem, here's how to do it:


If that's doesn't work I blame the instrument and I'll get something else