Surefly/Slick Combo

[Matthew P]

Currently have a 65 M20E with a Surefly on the left and a Slick on the right..had heard of individuals modifying it so that you get spark to ALL 8 plugs as opposed to the (4) you normally get...has anyone done that and what are the pros/cons....like the idea of all 8 plugs sparking during start sequence, that way of a mag fails you can still get the plane started if at a remote airfield and I would assume it would start a little better.

TIA

 

matt

Edited Wednesday at 12:57 AM by Matthew P

[Ragsf15e]

17 minutes ago, Matthew P said:

Currently have a 65 M20E with a Surefly on the left and a Slick on the right..had heard of individuals modifying it so that you get spark to ALL 8 plugs as opposed to the (4) you normally get...has anyone done that and what are the pros/cons....like the idea of all 8 plugs sparking during start sequence, that way of a mag fails you can still get the plane started if at a remote airfield and I would assume it would start a little better.

TIA

 

matt

Some people put the sf on the right mag and then modified the switch wiring so that it’s not grounded out during start.  Then they both fire.  I think @jetdriven might have a thread on this?

 

[Pinecone]

I just had a SureFly installed (by @jetdriven ).  It was installed as the right mag, so I still have the impulse coupling on my left mag.

I replaced the standard switch with toggles, so just flip both on for start.  Engine starts very quickly.

[Ragsf15e]

50 minutes ago, Pinecone said:

I just had a SureFly installed (by @jetdriven ).  It was installed as the right mag, so I still have the impulse coupling on my left mag.

I replaced the standard switch with toggles, so just flip both on for start.  Engine starts very quickly.

I will eventually get one on my 252 as well.  As i understand it though (could be wrong), both our mags are impulse mags and on for start anyway (different from an io-360).  In that case, I might do the left mag as the sf as it’s a real bear to get to under the alternator.  Not having to remove it every 500 hours might be nice.

[PT20J]

There is a mod for the dual mags to get all plugs to fire for starting. sim20-59a.pdf

If you have separate mags you need to to have both mags able to retard the timing if you want them both to fire. Since the left mag has the impulse coupling, you would need to put the SureFly on the right mag.

Pros: You get more plugs firing for maybe an easier start. However, the SureFly already puts out a hotter spark during starting and should start fine on one set of plugs.

Cons: The impulse coupling adds some complexity to the mag that isn't really needed.

[jetdriven]

The 252s have two impulse mags, and they both start the engine. But the left magneto on these things is hellishly impossible to get on and off, so we put the Surefly on the right side. We generally try to leave the impulse mag on the engine and then install the Surefly and then do the ground strap mod.

[Pinecone]

Hmm, I did not know that both mags on my 252 were impulse mags.

But it did help the shop to pull the right mag, as they needed to do that to get to the direct drive alternator, as it needed to be overhauled.

[PT20J]

Why is it that every part of a Mooney seems like the first part they started adding other parts around to build the airplane?

[Ragsf15e]

4 hours ago, jetdriven said:

The 252s have two impulse mags, and they both start the engine. But the left magneto on these things is hellishly impossible to get on and off, so we put the Surefly on the right side. We generally try to leave the impulse mag on the engine and then install the Surefly and then do the ground strap mod.

The left mag on my 252 looks downright easy to get to right now… of course that took a starter adapter failure which required removing the belt driven alternator, intercooler, starter and starter adapter.  If i had the choice, I might put the sf on the left just to avoid coming back in for the mag every 500 hours?  It looks like removing the right mag might “just” require removing the intercooler.