P-Mag Operating Temperatures

[RV7Grinner]

As one of the two recent failures referenced by John above, I am convinced that my failure last week was temperature related. I had just dropped off a passenger with a short shutdown followed by a hot start and taxi for takeoff. Failure (apparent loss of timing) occurred at start of takeoff role.
So, after replacement of "temperature dicolored circuit board", is there a science to pointing the blast tube at the right spot on the Pmag? Thanks for the help.

Bruce McGowan

[RV8R999]

I have 1 P-mag and a slick. I can't even begin to count the number of hot-turn-arounds I've done in the last 200 hours without any ignition issues at all (knock on wood) most of those during 95 OAT days in Southern Florida. I do have 3/4" blast tubes. FWIW

[N941WR]

Originally Posted by RV7Grinner

As one of the two recent failures referenced by John above, I am convinced that my failure last week was temperature related. I had just dropped off a passenger with a short shutdown followed by a hot start and taxi for takeoff. Failure (apparent loss of timing) occurred at start of takeoff role.
So, after replacement of "temperature dicolored circuit board", is there a science to pointing the blast tube at the right spot on the Pmag? Thanks for the help.

Bruce McGowan

Bruce, please contact me off list regarding your failure.

Thanks!
bill (at) repucci.com

[N941WR]

Dan,

Family issues came up this weekend and I didn?t even make it to the airport. Rain is expected for most of this week, so we may have to wait until next weekend for a temperature test.

Bill

[Brantel]

Originally Posted by RV7ator

So let's have a show of hands: who has had, or has first-hand knowledge of, P-mag problems in the last three years? Electrical or mechanical difficulties? Was SB3 incorporated? Blast tube or no?

John Siebold

Absolutely no problems with mine. I love it! Latest design and firmware.

Installed per the directions with a blast tube blasting on the fins of the Pmag.

My taddle tale sticker has never tripped and I see 400F on most climb outs.

[Bad Sheila]

I have just installed 2 E-Mags on my RV6 with O-320 and I am looking for the best blast tubes to use and a way to install them. Any pics and suggestions. Once I get these on I can fly.
Tony

[eddieseve]

I have two P-Mags in my RV7, 114 series, purchased second hand on this site, blast tubes are installed, latest software timing upgrade not done.

Over Christmas we did a series of joy flights for our staff, 1.5 hours of start stop activity in 37 deg C (98F) heat and had no issues at all, I know we are crazy but our staff loved it, bumps and all.

Cheers

[Richard Connell]

One more data point. I've got a sensor glued to the outside top of my left PMAG.

In flight at cruise altitudes it's always pretty cool around 120-140F.

On shutdown the temperatures rise quickly.

Here's the hottest flight I can remember since installing the PMAG. It also involved a quick turnaround. OAT on ground around 40C.
On startup the Temp was around 200F. Didn't really drop below 175F until TOC.


Standard blast tube install.

[N941WR]

FYI - The internal temperature probes on the P-mags are not calibrated, thus any temperature displayed by the EICommander or using the EICAD program should be taken with a block of salt.

Originally Posted by Bad Sheila

I have just installed 2 E-Mags on my RV6 with O-320 and I am looking for the best blast tubes to use and a way to install them. Any pics and suggestions. Once I get these on I can fly.
Tony

I hope you have P-mags and not E-mags installed. Emag is the company and they used to sell E-mags which where the same as the P-mag, less the internal generator.

Originally Posted by eddieseve

I have two P-Mags in my RV7, 114 series, purchased second hand on this site, blast tubes are installed, latest software timing upgrade not done.

...

Please get them in for the version 40 upgrade. It is critical, if you have toggle switches as it is a sure bet you will start the engine with one grounded and one ungrounded, which will reset the grounded mag.

(This upgrade will also help with starting as it sets the timing to 4 degrees after TDC when below 200 RPM. Above 200 RPM and the timing goes to 19.6* BTC at low RPM settings.)

[eddieseve]

I have the ACS key switch with the jumper removed, so both Mags become live at the same time

I have for the last year had the PMags timed to fire at approximately 4 degrees after TDC to ensure no kick back etc.

I initially ran the PMags with the timing at TDC but did experience the occasional kick back, since the timing change I have had no more kick backs and cannot notice any difference in performance, although I am seeing cooler CHTs as would be expected.

I am also running with the PMag jumper installed.

I would love to get the upgrade, but being in Sydney Australia there would be quite a substantial lag involved in shipping and them getting the units returned.

When I bought the two units, I contacted Brad and sent him the serial number information, he stated that they should be fine the way they are currently wired.

If only there was a way for end users to do their own software updates ???

Cheers