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how to test a slickStart

J

jwilbur

Well Known Member
I strongly suspect my slickStart is not doing what it should. For the first many flights I had no trouble starting the airplane. One or two blades and it's running. Lately, not so much. No change to my starting procedure but it just doesn't want to go. When it does catch it's all fine. But man, the battery is getting a workout.

What is the easiest way to test the slickStart unit to see if it's doing its job correctly?

Thanks,
 
Well, here?s one way.
Disconnect the starter cable. Cover the end with tape or shrink wrap.
Pull the plug on #1 that?s connected to the left mag (assuming that?s the one connected to the Slick start). Re-connect the high voltage lead to the plug. Lay the plug on the cylinder where it?s in contact with ground.
Ignition off, mixture idle cutoff. Be careful.
Turn the prop slowly, normal direction, until you?re on the number 1 compression stroke.
Have an assistant turn and hold the key on start. (If solo, jumper the start lead to 12 volts and leave the key on left).
Slowly move the prop toward TDC.
As you get there, you should see multiple sparks jump the plug gap, if the Slick start is working.
 
Another key symptom when it fails is if your motor tends to fire or start just as you release the start key. But the retard set of points not opening on the retard magneto will do the same.
 
If you have a mag timing box, you can verify that the retard breaker points are opening and closing, and also check that they are opening at the right time. Check the mark plate on the mag for the Lag Angle. it should be after TDC in any case.
 
TT on Mag?

On the mag the SS is connected to, how many hours since NEW on the MAG
and how many hours since OH?
 
For what it is worth I recently had a new 6393 suffer infant mortality in less than 5 hours flight time. The starting points worked fine in this case but the normal points went from totally normal to totally non operable in the last 2 hours. It was under warrantee, so there was no need to open it up and have a look inside. Shaking the mag it sounded like a baby rattle. However using a mag timing box allowed backup proof with a video of the problem.

I am not saying this is your issue, but it could be. Just remove the p leads on both the retard points and the normal points. Hook up the left lead to the P lead. Ground to the mag case. The right lead the the retard points post. The normal points should open at your desired timing of 20 or 25 BTDC and the retard points should open after TDC. It sounds like they might not be opening at all.

If it checks out OK then perhaps it could be the SS or a fuel issue.
 
F1R said:
For what it is worth I recently had a new 6393 suffer infant mortality in less than 5 hours flight time. The starting points worked fine in this case but the normal points went from totally normal to totally non operable in the last 2 hours. It was under warrantee, so there was no need to open it up and have a look inside. Shaking the mag it sounded like a baby rattle. However using a mag timing box allowed backup proof with a video of the problem.

I am not saying this is your issue, but it could be. Just remove the p leads on both the retard points and the normal points. Hook up the left lead to the P lead. Ground to the mag case. The right lead the the retard points post. The normal points should open at your desired timing of 20 or 25 BTDC and the retard points should open after TDC. It sounds like they might not be opening at all.

If it checks out OK then perhaps it could be the SS or a fuel issue.
Click to expand...

If the retard points are not opening and the SS is operating correctly wouldn't the engine NOT start at all? When the SS engages, I believe it grounds the normal points. If the retard points also fail to open then I'd be getting no sparks at all, right? (right mag is grounded by the starter switch).
 
Until you let go of the key or starter button, yes. Then it would fire or try and fire at that moment. An earlier post (Janekom) made that point. In the realm of all thing are possible and easy to check(with a timing box), I would check that the retard points are operating.
The 6393 that died young on me, would start with 1 blade or less, but because the normal points were not operating at all, the engine would die when a mag check was done. A bit confusing at first as if it starts with the LH 6393, how can it not run on it. So it was back on with the old tired 6393 and it runs fine but has no where near as good starting manners. Which is what you are describing.

I would check your retard points, with a timing box. No need to open it up as it should be under warrantee, based on the low hours.
 
F1R said:
Until you let go of the key or starter button, yes. Then it would fire or try and fire at that moment. An earlier post (Janekom) made that point. In the realm of all thing are possible and easy to check(with a timing box), I would check that the retard points are operating.
The 6393 that died young on me, would start with 1 blade or less, but because the normal points were not operating at all, the engine would die when a mag check was done. A bit confusing at first as if it starts with the LH 6393, how can it not run on it. So it was back on with the old tired 6393 and it runs fine but has no where near as good starting manners. Which is what you are describing.

I would check your retard points, with a timing box. No need to open it up as it should be under warrantee, based on the low hours.
Click to expand...

This makes some sense. Thank you.
 
Plugs

Got the slickStart manual and did a field test. It checks out fine. I bought a buzz box, learned how to use it. I checked the mag timing. Both mags were at 28 degrees. Seems they came this way from the factory. Both exactly in sync with each other and at 28 degrees. I set them to 25 degrees. I also used the buzz box to check the retard points. They check out fine. Open just past TDC (was just before TDC before I corrected the timing).

To do the timing I removed all the bottom plugs. They seemed somewhat fouled with an oily gunk all over the threads and coating the terminals. I cleaned them and reinstalled. Decided to remove and clean the top plugs while I was at it. Top plugs were pretty clean but I cleaned them anyway and put them back in.

Short story: The engine starts right up now just like it should - almost too easily. I'm guessing the problem was the fouled plugs made worse by the timing being wrong.

Thank you to everyone for the suggestions. Forced me to learn how to time the mags. And now I know the timing is correct and the slickStart is working properly.
 
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