The air museum I am a member of has a PT19 with the Ranger L440 engine that has had battery charging issues since is was rewired a number of years ago. It seems the charging system is simply not able to get charge back into the battery during taxi and idle (900-1500 rpm) and barely a “needle width” of movement on the ammeter at cruise speed (2000 rpm). I came across these old postings, and am in hopes there may be some more recent info out there that could help with diagnosis/resolution. Here is some configuration information:
Generator: (same as that referred to in the posts below)Ranger Engineering CorporationType 6631, No. 28021514V, 12A, 3300 RPM
Voltage Regulator:Delco Remy No. 1119165E
I found in a Ranger engine service manual that the Generator RPM = 1.5 x Crankshaft RPM
We took the following measurements yesterday (at the Generator/A+ output terminal)
Engine RPM Generator RPM Generator Output Voltage900 1350 5.0V1200 1800 10.5V1500 2250 12.5V
We took the same measurements with the field output connected directly to ground (to bypass the voltage regulator) and got essentially the same results.
At 1500 engine RPM, the generator just managed to exceed the reverse current relay cut-in voltage, and a small amount of charge (“needle width”) was indicated on the ammeter, but nowhere near enough to put back what starting the engine took out, much less powering accessories. I estimate the battery SOC at about 50%, with 12.3V across the terminals with no/light load. So, some questions:
1. Do the voltage measurements above look like normal or abnormal generator performance?2. What is the proper Make and Part Number for the voltage regulator that should be mated with this generator?3. Should we just reconsider the whole generator thing, and do an alternator conversion using the Jasco Model 6555-1 kit (consisting of the 6555-T alternator plus J12M20SP regulator)?4. Is the alternator conversion likely to solve our problem, i.e., effectively charge the battery at lower rpm (900-1500) as well as cruise rpm (2000)?
Any help would be greatly appreciated. Thanks!
Martin
pt19b2001Aug 29, 2012Curt,
What generator and voltage regulator are you using on your PT.
Thane
'Hide message history--- In fairchildclub@yahoogroups.com, ptcurt@... wrote:
>
> Cut in on mine is about 1600 rpm, engine that is. Not sure what the generator drive ratio is.
>
> Curt
> Sent via BlackBerry by AT&T
>
> -----Original Message-----
> From: "pt19b2001"
> Sender: fairchildclub@yahoogroups.com
> Date: Wed, 29 Aug 2012 03:24:24
> To:
> Reply-To: fairchildclub@yahoogroups.com
> Subject: [fairchildclub] Re: Voltage Regulator
>
> Thanks for the information. I will contact them and see what they have to say.
>
> Regards,
> Thane
>
> --- In fairchildclub@yahoogroups.com, "RMR" wrote:
> >
> > Hi,
> >
> > I have recently had success with Aerotech in Louisville. It will cost a little more than a NAPA regulator but should last longer and be correctly matched to your generator. John Evans at Aerotech should be able to answer most questions.
> >
> > www.aerotechlou.com
> >
> > Rick
> >
> >
> >
> > --- In fairchildclub@yahoogroups.com, "pt19b2001" wrote:
> > >
> > > I have a Ranger Engineering Corp generator to install on my PT19B. it's 14 volt, 12 Amp. My question is what voltage regulator should I use? Does the amperage of the regulator matter as long as it is over 12 Amp? I see several on eBay that are in the range of 35 amp.
> > >
> > > I think the 12 amps should be sufficient to charge the battery and run a couple of modern radios. Though I'm not sure what the cut in RPM is. It's marked 3300 RPM is that the cut in speed or the max output speed of the generator?
> > >
> > > Thoughts?
> > >
> > > Regards,