Engine ignition problem - Page 3

BobTurner · #21 06-07-2013, 06:15 PM

Well, it sounds like progress. I wonder if all the previous attempts have left your plugs coated with oil (was it blue smoke?). I'd pull the plugs and have a look.

airtractor8 · #22 06-07-2013, 06:32 PM

Quote:

Originally Posted by VETE76

ok, we installed a slick start system. now we get a lot of puffs of smoke and a few "bangs" but no start. any more suggestions?
ty
fred

Sounds like the timing is out on the mags to me. . Check that your mag to engine timing is correct."bangs" and smoke could be the mag firing the fuel/air charge on the exhaust stroke . Did you check the timing with no1 on the compression stroke? That happened to a guy around here with one of those mags. Turned out to be 180degrees out to the engine.
If its a new engine it could also be that the plugs got covered with preserving oil when you started cranking it and are now all gummed up. That also happened around here on an rv7 with new engine.

SportAvServ · #23 06-07-2013, 06:38 PM

I would think if the engine ran on a test stand and only time and hooking up a ignition switch is the difference, then I would disconnect both "P" leads and crank the engine, you can shut it off with the mixture if it starts. Please make sure you have full travel at both ends of the cables with a little bounce at the end of both the throttle and the mixture. Had a friend with his first start about a year ago and his ignition switch was grounding in the run position but not during start. One thing you need to do is to take the injectors out and just spray carb clean through them, also run your boost pump for a couple of seconds with rags under the ends of the fuel lines while the injectors are out. I have started a couple of new (pre ran) IO 360's and they had little bits of stuff in the injectors and the engine's did not want to run. Good luck, be careful out there.

RT
PS. Does your left mag have a spacer (easy to see, it's about an inch thick) between the engine and the mag?

Walt · #24 06-07-2013, 07:29 PM

Quote:

Originally Posted by VETE76

ok, we installed a slick start system. now we get a lot of puffs of smoke and a few "bangs" but no start. any more suggestions?
ty
fred

Please find someone locally to help you resolve your problems, this is the kind of thing that will get you in big trouble on that first flight if you don't know what you are doing

Toobuilder · #25 06-07-2013, 08:02 PM

Quote:

Originally Posted by Walt

Please find someone locally to help you resolve your problems, this is the kind of thing that will get you in big trouble on that first flight if you don't know what you are doing

+1 on that!

This is beginning to sound very much a "back to basics" situation....

Is the timing correct?
Are the high tension leads routed properly?
Are the p leads/ignition switch terminals correct?
Are the plugs clean?
Are the fuel lines clear?
Is the fuel fresh?
Are the valves operating?
Etc, etc, etc....

These engines are dirt simple... Any competent A&P should be able to verify all of this and more in a few minutes.

Jesse · #26 06-09-2013, 02:26 PM

I have seen a problem before where the leads in the harness were the wrong lengths, so they were on the wrong plugs. The leads will all have a cylinder number as well as T or B. the engine has cylinder numbers at the base of the cylinders on the case. Make sure you have those right, because that could definitely cause the problem you are seeing. If it was run on a test stand, then it should be something simple. Think through and check everything you loosened/tightened on the engine and check that. The plug wires are almost certainly on that list.

az_gila · #27 06-09-2013, 03:08 PM

Quote:

Originally Posted by Jesse

I have seen a problem before where the leads in the harness were the wrong lengths, so they were on the wrong plugs. The leads will all have a cylinder number as well as T or B. the engine has cylinder numbers at the base of the cylinders on the case. Make sure you have those right, because that could definitely cause the problem you are seeing. If it was run on a test stand, then it should be something simple. Think through and check everything you loosened/tightened on the engine and check that. The plug wires are almost certainly on that list.

Aren't engines sometimes run on the test stand with "spare" factory mags, and then shipped with the new users mags in a seperate box?

Jesse · #28 06-09-2013, 03:15 PM

I've never heard of that, but it could be. I'd feel conned by receiving an engine that had been run with other components used than the ones shipped with the engine. If you're going to test run my engine, it is for break in, timing, fuel tuning, etc.

David-aviator · #29 06-09-2013, 04:48 PM

Fred,

The engine came direct from Lycoming, it is past due to contact the them..

This engine should start with no issues right now without adding anything to augment the ignition system.

DanBaier · #30 06-09-2013, 06:30 PM

Quote:

Originally Posted by az_gila

Aren't engines sometimes run on the test stand with "spare" factory mags, and then shipped with the new users mags in a seperate box?

Yep - I have a Lyc that I bought years ago and that's exactly what was done. Not only the mags, but the carb too. After they took it off the stand, they crated it up and threw in a box for the carb and the mags. (This was a Lyc overhaul.)

The engine I bought from Mattituck came "as run." I believe I did have to reinstall the carb.

Dan