Cessna 400 Series Voltage Regulator Upgrade Kit

[Skymasterdriver]

Can we buy you wire diagram and 337 paper work and us zeftronics regulators or is the Cessna ones all we can use ?

[california Sky]

Good morning

Looking to purchase the diagrams have a set of regulators available.

Please advise

[mshac]

If you just need copies of all the FAA paperwork and the step-by-step instructions I wrote, plus tech support (if needed) its just $100. I will email everything immediately upon payment. Please PM me for payment details.

[patrolpilot]

Another successful install mshac! My shop loved the package!

[mshac]

Originally Posted by patrolpilot

Another successful install mshac! My shop loved the package!

I'm very happy to know you're enjoying the upgrade to true parallel alternators!

Makes you wonder why Cessna didn't do it this way themselves, since they already had the parts and the design ready to go.

[JAG]

Hi Mark,

Will your modification work for the 337A model as well? Mine has the two 30 amp alternators, and I have just replaced one of my voltage regulators and about to change the other...

These older planes have just 1 regulator for both alternators (the second one is just a spare), so one alternator is always carrying more load.

Thanks,
Jeff

[mshac]

JAG, your alternators would work fine with this system. It would require 337 field approval, just like all the other installs, but I've yet to hear of anyone being denied the 337, as its a simple and safe upgrade.

EDIT:

There would be additional wiring required for the older airframes like yours. This upgraded system requires each alternator to have its own dedicated voltage regulator. I don't know how the wiring was done by Cessna on a 337A, but you would need independent circuits to each alternator.

I hope this helps. Feel free to PM me anytime.

[mshac]

Originally Posted by Skymasterdriver

Can we buy you wire diagram and 337 paper work and us zeftronics regulators or is the Cessna ones all we can use ?

This upgrade only covers factory Cessna voltage regulators. Its possible that a system could be designed using the Zeftronics VRs, but it may well be "a bridge too far" for an easy field 337 approval because it strays too far from the original design.

This modification takes an existing, approved system from 400 series aircraft and applies it to the Skymaster, with no changes to the POH or placards. The FAA seems to view this approach favorably.