N261TA engine rebuild questions

[Gubni]

I sent my engine off to Jewell Aviation as many recommended. David had two questions for me today do I want to upgrade my TSIO-360-MB to an SB? He said it's mostly just a fuel system upgrade. His other question was about the mags. I was going to just put bendix mags on it, but I have read about people upgrading to electronic ignition. I don't know the pros and cons of either of these upgrades. I do know that some upgrades may not be worth the hassle and others can be amazing especially since I'm already there. I look forward to your wisdom. 

[1964-M20E]

MB to SB I don't know what the difference is.  Ask them what are the benefits and what is the costs for the upgrade.  Sometimes we get "better and there is not noticeable benefits.  On the other hand the benefit maybe down the road in less maintenance.

 

However, I just did my engine and went with the Bendix mags.  I didn't want to deal with electronic ignition at the same time as changing the engine but someday I will.

 

 

[smwash02]

The SB is what the Encore uses and provides 220HP at 39" turning 2600 RPM.

I don't know about the legalities of doing it, but if it's an option it would be a nice upgrade.

 

[LANCECASPER]

2 hours ago, Gubni said:

I sent my engine off to Jewell Aviation as many recommended. David had two questions for me today do I want to upgrade my TSIO-360-MB to an SB? He said it's mostly just a fuel system upgrade. His other question was about the mags. I was going to just put bendix mags on it, but I have read about people upgrading to electronic ignition. I don't know the pros and cons of either of these upgrades. I do know that some upgrades may not be worth the hassle and others can be amazing especially since I'm already there. I look forward to your wisdom. 

You'll have to look at your 261 Conversion STC paperwork. I believe it specifies the -MB engine, since the -SB probably wasn't available back then. If the STC holder is still in business you might check with them to see if the STC has been updated to include the -SB engine or if it can be. I wouldn't go ahead with an -SB without it being on the STC since an unsympathetic IA down the road may not sign off on your annual with the "wrong" engine on it.

Regarding the electronic ignition, sad to say I don't think the units available today are quite there yet. Even so, you can only use one electronic unit and one regular mag.

[Aerodon]

I may be wrong, but I have not seen electronic mags for a turbo charged engine?

I don't think there is any legal basis for turning the MB engine into SB for the 262 upgrade.  For sure you don't get the gross weight increase of the Encore, and the MB is happy enough at 210 hp, just going to wear out sooner at 220hp.  I would not do it.  

Aerodon

 

 

 

[carusoam]

The programmable timing shift probably isn’t available to TC’d engines still…

So… there may still be benefit to having an electronic mag…

If my plate was full, I’d be happy with the pair of Bendix…

I’m still waiting on a few MSers to report their experience with electronic mags on their IO550s….

 

Getting the plane flying and getting the pilot transitioned to the new hardware is plenty of challenges…

Getting the S block is icing on the cake if legal…

Use the search around here… it is a common question to ask about the benefits of the various engines available to the M20K line…

By the time you are done reading….  The Rocket will sound like a great next step….  

 

PP thoughts only, not a mechanic…

Best regards,

-a-

[Ragsf15e]

12 hours ago, Aerodon said:

I may be wrong, but I have not seen electronic mags for a turbo charged engine?

I don't think there is any legal basis for turning the MB engine into SB for the 262 upgrade.  For sure you don't get the gross weight increase of the Encore, and the MB is happy enough at 210 hp, just going to wear out sooner at 220hp.  I would not do it.  

Aerodon

 

 

 

Surefly is approved for TC’d engines, but it must be set on fixed timing.  Check the AML for specifics.

On 28v systems there have been some hiccups.  They are currently addressed with a power conditioner installed with the SF.  In the future they will be part of the unit.  On 28v, I’d probably wait for that.  Especially if you’re limited to fixed timing.  On 14v NA engines, I think it is a worthy change when you are at mag overhaul anyway.

[Gubni]

I think its clear I should wait on the electronic mag. Mine is a turbo 12v, but I think it's best to get it going for now. The owner of the STC for the 261 conversion is not available and I can't get an update for the SB mod. Does that mean I can't or shouldn't do it? My engine builder said it's the same cost either way and he does it all the time.

[Ragsf15e]

1 hour ago, Gubni said:

I think its clear I should wait on the electronic mag. Mine is a turbo 12v, but I think it's best to get it going for now. The owner of the STC for the 261 conversion is not available and I can't get an update for the SB mod. Does that mean I can't or shouldn't do it? My engine builder said it's the same cost either way and he does it all the time.

Have you read the STC language closely to see exactly what it says about the engine?  Another option is to call Maxwell or Top Gun or another msc and discuss.  I’m sure they’ve dealt with it.

[201Steve]

I believe @gsxrpilot had this conversion done at Jewell. Or maybe a different deal. Idk. 

[kortopates]

1) none of the 231's nor STC'd to 261 or 262 are eligible for the -SB or Encore engine. Only 252's with serial number starting 25-1001 are eligible.
2) Even with the 252's starting at 25-1000, the airframe would first have to have the dual brake option installed and then complete airframe mods to allow for the Encore conversion - or both done together with the engine. The Engine is the easy part, the airframe parts can be substantial depending on how sourced.
There is no legal path for just placing the -SB engine on a 231 or 252 airframe.

But what makes the Encore conversion with -SB engine so desirable for 252 owners is the increase of 230 lbs of max gross weight. My useful load after conversion is over 1100 pounds.

The Surefly mag is a good separate mod for any of the K engines, given its turbo there is no advance and frankly you wouldn't want it anyway and even if you truned it on, you'd never see any advance because Turbo MAP rarely gets low enough for the advance to kick till in a descent. Improved reliability over a pressurized mag is the real benefit.

[carusoam]

Paul, your technical back-ground is greatly appreciated… 

Thanks for sharing all the details.

Best regards,

-a-

[Will.iam]

Yea Paul beat me to it. I have a 252 and would love to put the SB engine on it but the airframe mods will run me at least 15k in parts not including labor and then I have to overhaul the engine too so big chuck of change to do it all at once. I’m still sweating what my first annual will set me back and I have laundry list of squawks going into it.  
I talked to the surefly rep at Oshkosh one of the only booths I got to go to and asked when the new version of their system with the beefed up voltage regulator on their system would be avail for purchase and he said probably not til the beginning of next year. That made me a sad panda and will have to IRAN both mags at this annual. My timing is horrible. 

[kortopates]

25 minutes ago, Will.iam said:

Yea Paul beat me to it. I have a 252 and would love to put the SB engine on it but the airframe mods will run me at least 15k in parts not including labor and then I have to overhaul the engine too so big chuck of change to do it all at once. I’m still sweating what my first annual will set me back and I have laundry list of squawks going into it.  
I talked to the surefly rep at Oshkosh one of the only booths I got to go to and asked when the new version of their system with the beefed up voltage regulator on their system would be avail for purchase and he said probably not til the beginning of next year. That made me a sad panda and will have to IRAN both mags at this annual. My timing is horrible. 

No need to overhaul the engine to a -SB unless you really want too. Its very easy an inexpensive to convert it. The obstacle is those expensive and time consuming airframe mods for sure. 

But I wouldn't sweat the Mag IRAN's. I pull mine off every annual to open up anyway, since they're pressurized mags. So an extra $350 a mag to IRAN them every 500hrs/5yrs hardly affects my annual operating cost. Not to mention the Surefly is only going to replace one of them.

[Will.iam]

19 hours ago, kortopates said:

No need to overhaul the engine to a -SB unless you really want too. Its very easy an inexpensive to convert it. The obstacle is those expensive and time consuming airframe mods for sure. 

But I wouldn't sweat the Mag IRAN's. I pull mine off every annual to open up anyway, since they're pressurized mags. So an extra $350 a mag to IRAN them every 500hrs/5yrs hardly affects my annual operating cost. Not to mention the Surefly is only going to replace one of them.

So i can overhaul the MB engine when it starts making metal to an MB engine and then later say 500 hours or so convert it to an SB once i have the airframe mods done?  That’s good to know. 

[kortopates]

34 minutes ago, Will.iam said:

So i can overhaul the MB engine when it starts making metal to an MB engine and then later say 500 hours or so convert it to an SB once i have the airframe mods done?  That’s good to know. 

Basically, there are two airframe mods - the double puck brakes which can be done anytime on their own, but need to done before or at the same time as the actual Encore mods. The Encore mods require the engine to be re-configured to an -SB along with the re-balancing flight control surfaces to new specs, plus re-marking or re-configuring IAS, MAP, RPM instruments, new POH and new wt & bal update. Most have been done by simply re-configuring the engine since the engine was fine and didn't need overhauling.  Its rare, but I have one client with just the double puck brakes mod that has so far chosen not to do the Encore mod. But i'll bet when he sells the new owner will do it immediately.

[Will.iam]

I can already flat spot a tire with just the single brake puck I wish I had less stopping power not more. Are the double puck brakes as touchy as the single puck. Have thought of adding an air bubble or 2 to make my brakes more spongy to avoid locking up the wheels. Really with they had antilock brakes. 

[carusoam]

Will,

For this challenge… I invite @Hank to describe braking technique…

There are certain details to consider to get max braking… in a Mooney…

It is crazy easy to flat spot a set of tires… at highway speeds…

Best regards,

-a-

[Hank]

8 hours ago, carusoam said:

Will,

For this challenge… I invite @Hank to describe braking technique…

There are certain details to consider to get max braking… in a Mooney…

It is crazy easy to flat spot a set of tires… at highway speeds…

Best regards,

-a-

I don't have any exceptional braking techniques, I just don't use them until the ASI is below 50. Keep heels on the floor around the pattern and don't be in a hurry to brake. I generally reach 50 right after raising the flaps, to reduce lift and put weight on the tires.

[Ragsf15e]

10 hours ago, Will.iam said:

I can already flat spot a tire with just the single brake puck I wish I had less stopping power not more. Are the double puck brakes as touchy as the single puck. Have thought of adding an air bubble or 2 to make my brakes more spongy to avoid locking up the wheels. Really with they had antilock brakes. 

You use the brakes?  I might need them taxiing downwind or during the runup, but otherwise, don’t use them much.

[rbridges]

18 minutes ago, Ragsf15e said:

You use the brakes?  I might need them taxiing downwind or during the runup, but otherwise, don’t use them much.

but don't you have to land a mooney at 110 knots?  

[EricJ]

12 hours ago, Will.iam said:

I can already flat spot a tire with just the single brake puck I wish I had less stopping power not more. Are the double puck brakes as touchy as the single puck. Have thought of adding an air bubble or 2 to make my brakes more spongy to avoid locking up the wheels. Really with they had antilock brakes. 

From race car experience, in addition to potentially increasing the effective pressure area, multiple pistons in the caliper increase the ability to modulate the brakes, i.e., a more linear translation of pedal pressure to stopping torque.   This decreases the likelihood of unintended lockup.

 

 

Edited August 4, 2021 by EricJ

[kortopates]

In addition to Eric's fine comments above, if you end up using the added useful load alot they found that in the first couple years of Bravo operations (at heavier weights)  that the single puck brake disk pads where wearing out at an accelerated rate. Going to double puck brakes eliminates the quick wearing and they sure do give much geater braking control; which is why some have added them without strictly needing them. (K's and early Bravo's alike).

Edited August 4, 2021 by kortopates

[geoffb]

I've got the dual pucks on mine.  I think Goodyear owns the stc ;-)

When you're new to them, they're hard on tires.

[Will.iam]

Part of the reason I’m having a hard time with the brakes is landing at my home field of only 2500ft and i have 2 speed bump like sections in the lower third of the runway that landing to the north pops me back into the air and landing south you need to scrub the speed before getting to the bumps or you might not get it stopped by the end of the runway so its really like landing on a 2000 ft runway trying to avoid the bumps.