EIS4000 - Replace VTACHGEN 2 with MGL TACH-SLICK

[CHI_Pilot]

My 2011 Vans RV-6a has a VTACHGEN 2 which, I think, is problematic. When the rpms go above 2400 for a minute or two, the EIS4000 rpm drops to zero and stays there for the remainder of the flight. The other day after I landed, the RPM started working again when taxiing.

Some newbie questions:

It looks like Vans no longer sells the VTACHGEN 2 so I need to switch to a hall effect transducer. Correct?

I have an IO-360 with two mags (Right - 66GP-OSANN, Left - 66GC25SFNN)

These show up at Spruce as Lycoming Mags - but I believe they are Slick Mags (vs Bendix). Is that Correct?

If so, do I need this part: https://www.aircraftspruce.com/catalog/inpages/mgltachslick.php

And, lastly, does it go on the right or left mag, or does it not matter? The engine is a young engine with 150 hours. I intend to replace the mag at 500 with an e-mag. Do I replace the right or left mag at that point? Does that impact where I connect the MGL sensor?

Thanks... in advance

 

[Tankerpilot75]

Frankly the first thing I would do is to check the wiring between the Tach and your EIS. I’ve experienced both MP and Tach RPM readings go intermittent on my EIS because of wiring and connection issues. Do this before you commit to any part replacement.

 

[planenutz]

Some newbie questions:

It looks like Vans no longer sells the VTACHGEN 2 so I need to switch to a hall effect transducer. Correct?

I have an IO-360 with two mags (Right - 66GP-OSANN, Left - 66GC25SFNN)

These show up at Spruce as Lycoming Mags - but I believe they are Slick Mags (vs Bendix). Is that Correct?

If so, do I need this part: https://www.aircraftspruce.com/catalog/inpages/mgltachslick.php

And, lastly, does it go on the right or left mag, or does it not matter? The engine is a young engine with 150 hours. I intend to replace the mag at 500 with an e-mag. Do I replace the right or left mag at that point? Does that impact where I connect the MGL sensor?

Correct - Vans no longer sell the VTACHGEN 2 sensor and it appears they're no longer manufactured. My research leads me to beleive these were in fact a Stewart Warner product in common use on some vehicles however reliability seems to have been an on-going issue. I've recently had to replace mine too.

It is most likely that you have Slick magnetos but there is a chance you have Bendix. Without checking the manuals to be certain, I believe you've quoted the Magneto serial numbers, not the part numbers. I would have expected your mags to have a part number similar to 4370 - or similar.

If these are Slicks, then yes, that alternative sensor you linked to is the one you need.

Whether you place this on the left mag or the right mag is up to you, it really doesn't matter. Naturally it would be more sensible to place the sensor on the magneto you intend to retain on the engine in the long term.

In respect to replacing the magneto with an E-Mag - I'm sure there are lots of opinions on this and others will provide you with their reasons, but you might find it best to place this on the left side for easier starting. That said, I installed a SUREFLY 4N on the right side of my IO-360 and retained the standard Slick mag on the left. I'll probably replace the Left magneto with a SUREFLY at the next 500 hour Inspection... 428 hours away (!).

Hope that helps.