Rough engine on EI

rv6aviator · #1 08-18-2010, 03:24 PM

Gentlemen. I have an RV6, w/ Lyc 0360- Recently developed rough running which seems isolated to the EI side since - runs ok on mag side only and somewhat rough on both. All wiring and plugs have been checked. The EI is on right side and has no identifying marks anywhere on it that I can find. Is has aluminum look round housing w/ a multi pin plug near top and a small green plastic thingy ( I know ,I know) just south of centre which looks like it might be an LED light. 2 coils are mounted on top of the engine, rectangular, flat on top. Sorry don't have pics of this yet but can anyone identidy the unit and more importantly, how to dianose the rough running and how to fix. I defer to your greater knowledge.

Birkelbach · #2 08-18-2010, 03:34 PM

Does it look like this?...

http://www.myrv7.com/viewimage.php?pictureid=383

Another shot is here...

http://www.myrv7.com/viewimage.php?pictureid=473

If it does then it's a Lightspeed hall effect sensor.

Here are some manuals...

http://www.lightspeedengineering.com...s/Ignition.htm

The little green dot is in fact an LED that is used for timing. The details are in the manual.

rv6aviator · #3 08-18-2010, 04:50 PM

That is exactly what it looks like. Don't know why it would not have some id on the case but... Tks very much

RVadmirer · #4 08-18-2010, 05:04 PM

Check your PMs

Ron Lee · #5 08-19-2010, 02:37 PM

I had a rough running Lightspeed a few years ago and replacing several parts fixed the problem after returning to the original part. I think that removing and replacing the two DB connectors cleaned off some corrosion.

Another time a wire connection to one of the coils failed and that was easily fixed.

Do read and follow the troubleshooting guide in the links you were given.

rv6aviator · #6 08-19-2010, 03:03 PM

Cleaned the connector at the Hall effect unit, checked the coils (good), checked the plugs again (good) and moved the Hall unit as per Lightspeed Manual kindly linked to me above. The led light came on and off as suggested but the off point was about 5* arc clockwise to where the unit was set before (25*engine). Ran engine and not getting that hard occasional knock I was getting but still not real smooth on the EI. Do you set the Hall unit where the LED light first comes on or where it goes off or in between- the manual is not specific on that?

Birkelbach · #7 08-19-2010, 03:25 PM

You set it as the LED turns OFF. If you use the point where the LED comes ON you will be about 5 deg off. This was a problem with my engine when I first got it.

IIRC if you are turning the engine in the normal direction of rotation the LED should come on around 5 deg BTDC and then go off right at TDC. (For 25 deg engines)

I did do the automotive timing light test and it's a little nerve wraking having the engine running inside and being trapped between the wing and the prop, but that's how you get the definitive answer on your timing. You may have a MAP leak or something causing the timing to be off. The HAL effect sensor won't tell you that, but the timing light will.

Schmeddz · #8 08-27-2010, 04:38 AM

90 percent of the problems will either be wiring related or a vacuum leak. On the Light speed it will probably be wiring. Check your connectors and don't be afraid to open the DB connectors and check the soldered connections. You might be surprised at what the soldered joints look like. (Bad, cold connections.)