Engine ignition problem

[VETE76]

ok here's update.
we installed the slick start. wow, you talk about sparks!!. but no start.
mags are timed perfect. start switch wired correctly. our last start attempt had puffs of smoke we never had before. and a back fire or two. spark plug wires connected to correct plugs. so we removed all 4 bottom plugs. disconnected starter. turned prop by hand until tdc #4. grounded all 4 plug wires and then turned master on and turned key to start. #1 sparked . conclusion, plug wires are marked wrong. will verify with lyc in the morning. my engine paperwork says engine ran for 59 min in test cell.
fred

[Walt]

Mag point opening (timing) can be correct, but for the wrong cylinder.

[Jesse]

So, either the harnesses are bad, or they're on the wrong side, or the mags are not right on the engine. You could pull the mags, set the engine to tdc on cyl 1, put the timing pin in the correct hole on the mag and reinstall, it could be that they had the engine on the wrong stroke when they inserted the mags, obviously not having run it that way, then shipped it. Personally, I'd read them the riot act and ask to be made right. Overall, if this fixes the problem, then you should be good. So, depending on the firing order, is it possible that the tdc mark for cyl #1 on the compression stroke could be cyl #4 on the exhaust stroke and vice versa? If so, that could easily explain the mistake. What is the firing order on that engine? If 1 & 4 are not next to each other, then that could well be the cause. I'd check the easiest things first, which would be the harnesses possibly on the wrong mags.

[BobTurner]

Originally Posted by David-aviator

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.

My IO540 came direct from Lycoming with retard mags, no impulse couplings, and no Slick start.

Ignition leads were attached to mags only, bundled and wrapped in plastic.

Walt's diagram shows firing order as 1-3-2-4, so 1 and 4 are not opposite each other.

[Jesse]

A call to Lyc is definitely in order, but short of sending the engine back to them, you may be on your own to figure it out. You verified it's an ignition problem, so next you may want to do the same test for all 4 cylinders. If the firing order is correct, and they are just out or sequence, then the mag timing to the engine is the problem. Pull the mag, insert the pin (in the hole for the correct rotation), turn the engine to 25 btdc on cyl 1 and reinsert the mag. Also, you could look in the back of the engine to see if the timing mark on the gear shows correctly, although this doesn't matter much, but it can determine if the gear was installed correctly

Also, it may just be the one mag that is wrong. Maybe try grounding the mag that you know is wrong and disconnect the p-lead from the other mag and see if it will start, without the slick start. If it runs there, then only one mag is wrong.

[Andy Hill]

mags are timed perfect

Can you let us know "how" you timed them and with which marks?

NB Marks on the back of the flywheel tend to align with the crankcase split i.e. vertically up. Marks on the front of the flywheel with the starter i.e. about 5 o'clock as you look at the engine.

[VETE76]

Originally Posted by Andy Hill

Can you let us know "how" you timed them and with which marks?

NB Marks on the back of the flywheel tend to align with the crankcase split i.e. vertically up. Marks on the front of the flywheel with the starter i.e. about 5 o'clock as you look at the engine.

they were mounted from factory. i call an AP friend of mine and he went over to it and check the timing for me. i wasnt there.

[VETE76]

Originally Posted by BobTurner

First, get another mechanic. Your engine is a certified type. And a brand new mag is less than half his estimate for an impulse coupler.
Check easy stuff first. Are the correct cylinders hooked to the correct high tension leads? Is the ignition switch wired correctly? (check with an ohmmeter that left mag P lead is open, right P lead is shorted, with key on start).
Then harder stuff, like mag timing.

yep a brand new mag w/coupler is less than what my mechanic but he added in the possible core charges for a mag and a coupler. now i have no core mag so me giving him a brand new mag as core is like an additional $7-900 lost, then core for coupler is another chunk of change,,,,, he had all that in the new price because its the bottom line of what it is costing me for the coupled mag.

[VETE76]

as of 10:30 am 2day I now have a strong running io360 thanks to Dave l. the mags were timed perfect but the internals were timed to a different cylinder. he took the mags apart and put them together the correct way, installed them, set them and said 100% guarantee it will start 1st time especially with that slick start u added. wow! it did!!!!!in the words of a famous rock and roll band "excuse me, while I kiss this guy", not really, he was old and ugly soo I just shook his hand!! he also showed me that there wasn't any sign of oil inside the mag, he said that proves these mags never ran on this engine. I called lyc they were very concerned that this happened. waiting for an answer. thanks to all who helped , this is a great community of people!!
fred

[Weasel]

Originally Posted by VETE76

he also showed me that there wasn't any sign of oil inside the mag, he said that proves these mags never ran on this engine.
fred

Interesting!!!!