---------------------------------------------------------- RV-List Digest Archive --- Total Messages Posted Wed 06/29/11: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:06 AM - mag timing (thomas sargent) 2. 08:37 AM - Re: mag timing (Linn Walters) 3. 08:46 AM - Re: mag timing (Michael Kraus) 4. 09:05 AM - Re: mag timing (Ed Holyoke) 5. 09:33 AM - Re: mag timing (thomas sargent) ________________________________ Message 1 _____________________________________ Time: 08:06:39 AM PST US Subject: RV-List: mag timing From: thomas sargent I bought the TP105 "mag synchronizer" from Spruce. My plane has only the left magneto. I use a Lightspeed ignition on the right. I was fairly sure this could be used to time a single magneto, but the instructions don't even mention that. Did I buy the wrong buzz box, or is the timing procedure so "well known" that they don't even explain it? -- Tom Sargent, RV-6A ________________________________ Message 2 _____________________________________ Time: 08:37:25 AM PST US From: Linn Walters Subject: Re: RV-List: mag timing I couldn't find the tp105 on spruce, but the 'buzz box' should work fine. I'm guessing that you have an impulse mag on the left. Remove one plug from each cylinder to prevent inadvertent firing. Rotate the engine until you feel compression on #1. Look at the engine data plate to see what the timing BTDC is. Locate this mark on the flywheel. I use the back side which lines up with the case split. The front marks line up with the starter ..... never could find the 'hole' mark! Turn the prop until you hear the 'click' as the impulse breaks. This should be near TDC. Move the prop backwards until the mark lines up with the case split. This should be the same degree mark as is on the data plate. Typically 25 deg BTDC but can vary on different engines. If the mark doesn't line up, rotate the mag until it does. You're only timing the left mag so the right isn't connected because of the lightspeed. Once the left mag is timed, use the Lightspeed instructions to time the right side. Hope this helps. Linn On 6/29/2011 11:03 AM, thomas sargent wrote: > I bought the TP105 "mag synchronizer" from Spruce. My plane has only > the left magneto. I use a Lightspeed ignition on the right. I was > fairly sure this could be used to time a single magneto, but the > instructions don't even mention that. Did I buy the wrong buzz box, > or is the timing procedure so "well known" that they don't even > explain it? > > -- > Tom Sargent, RV-6A > * > > > * ________________________________ Message 3 _____________________________________ Time: 08:46:07 AM PST US Subject: Re: RV-List: mag timing From: Michael Kraus The synchronizer tells you when the points open and close (ie fire). If you have 2 mags, it will show you how close they are together (ie do they fire a t the same time, or one before the other). Use this along with some way to t ell degrees before TDC and you want the single mag to beep at typically 20 d eg before TDC (depending on engine and cylinder compression). Sent from my iPhone On Jun 29, 2011, at 11:03 AM, thomas sargent wrote: > I bought the TP105 "mag synchronizer" from Spruce. My plane has only the l eft magneto. I use a Lightspeed ignition on the right. I was fairly sure th is could be used to time a single magneto, but the instructions don't even m ention that. Did I buy the wrong buzz box, or is the timing procedure so "w ell known" that they don't even explain it? > > -- > Tom Sargent, RV-6A > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 4 _____________________________________ Time: 09:05:55 AM PST US From: Ed Holyoke Subject: Re: RV-List: mag timing Howdy Tom, Can't find the TP-105 on ACS' site. I use the "Inductor Magneto Synchronizer": http://www.aircraftspruce.com/catalog/topages/synchronizer.php For this unit, remove one set of spark plugs, top or bottom. Find top dead center on #1 by moving the prop until it blows pressure past a finger on the spark plug hole. If the mag has an impulse coupling, go far enough to hear the snap, then back up to about 35 degrees BTDC and sneak up on 25 BTDC by the mark on the flywheel that lines up with the hole in the starter casting. This gets any gear lash out of the picture. Put a drill bit in the hole as a pointer to get a better look at it's relationship to the flywheel mark. Hook the black wire to ground and one or the other of the colored leads to the P-lead on the mag. Turn the mag switch on. Turn the buzz box on. Move the prop back and/or forth until one of the lights goes out and the sound changes. Ignore the other light since it isn't hooked up. Look at the flywheel again to see where the timing really is. Loosen the mag hold downs and adjust as necessary to get it to where the light goes out exactly when the 25 degree mark lines up when you sneak up on it. Snug the hold downs on the mag before you check timing. The timing will often change slightly as you tighten the magneto hold downs, so it may take a few (or many) tries to get it just right. Have fun with it. Pax, Ed Holyoke On 6/29/2011 8:03 AM, thomas sargent wrote: > I bought the TP105 "mag synchronizer" from Spruce. My plane has only > the left magneto. I use a Lightspeed ignition on the right. I was > fairly sure this could be used to time a single magneto, but the > instructions don't even mention that. Did I buy the wrong buzz box, > or is the timing procedure so "well known" that they don't even > explain it? > > -- > Tom Sargent, RV-6A > * > > > * ________________________________ Message 5 _____________________________________ Time: 09:33:21 AM PST US Subject: Re: RV-List: mag timing From: thomas sargent Ed: Thanks for that description. That helps a lot. The TP-105 is the mfr. number. Spruce lists it on the same page with the E-50. It's the "Mag timing light Industrial Typ" at the bottom of the page. p/n 12-01279 On Wed, Jun 29, 2011 at 9:02 AM, Ed Holyoke wrote: > ** > Howdy Tom, > > Can't find the TP-105 on ACS' site. I use the "Inductor Magneto > Synchronizer": > http://www.aircraftspruce.com/catalog/topages/synchronizer.php > > For this unit, remove one set of spark plugs, top or bottom. Find top dead > center on #1 by moving the prop until it blows pressure past a finger on the > spark plug hole. If the mag has an impulse coupling, go far enough to hear > the snap, then back up to about 35 degrees BTDC and sneak up on 25 BTDC by > the mark on the flywheel that lines up with the hole in the starter casting. > This gets any gear lash out of the picture. Put a drill bit in the hole as a > pointer to get a better look at it's relationship to the flywheel mark. Hook > the black wire to ground and one or the other of the colored leads to the > P-lead on the mag. Turn the mag switch on. Turn the buzz box on. Move the > prop back and/or forth until one of the lights goes out and the sound > changes. Ignore the other light since it isn't hooked up. Look at the > flywheel again to see where the timing really is. Loosen the mag hold downs > and adjust as necessary to get it to where the light goes out exactly when > the 25 degree mark lines up when you sneak up on it. Snug the hold downs > on the mag before you check timing. The timing will often change slightly > as you tighten the magneto hold downs, so it may take a few (or many) tries > to get it just right. Have fun with it. > > Pax, > > Ed Holyoke > > On 6/29/2011 8:03 AM, thomas sargent wrote: > > I bought the TP105 "mag synchronizer" from Spruce. My plane has only the > left magneto. I use a Lightspeed ignition on the right. I was fairly sure > this could be used to time a single magneto, but the instructions don't even > mention that. Did I buy the wrong buzz box, or is the timing procedure so > "well known" that they don't even explain it? > > -- > Tom Sargent, RV-6A > > * > > * > > -- Tom Sargent ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv-list Browse Digests http://www.matronics.com/digest/rv-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.