Jim P

Jim P

Well Known Member
OK, I finally started the Slick SB work and had the parts on hand to replace brush and cam on the right mag. Everything seemed to be going OK for the right mag, L rotation. I did the following after pinning the gear to L:

1) removed the distributor block
2) Pulled the small gear
3) Used the E-Gap T150 timing tool to check and reset the timing making sure I used the tool on the L cutout in the rotor, rotating the mag housing clockwise so the T150 stopped against the pole laminations. Then set the points to where they "just opened" using a buzz box.
4) Reassembled, ensuring the large gear was pinned to L and the small gear was alligned to L as well.
5) Re-assembled the cover and installed on the engine
6) Finally, checked that the mag was timing at 25 BTDC.

After re-installing p-lead, groung, plugs and ingition harness, I did a test run. The left mag, which I hadn't touched ran normally, but the one I did, ran very rough. It runs but it's really rough. I re-checked the mag timing and it appears fine.

I'm thinking I've honked up the internal timing somehow. Any clues?

Thanks.
 
Jim, any chance you watched the EGT's (assuming you have individual EGT's) to see if it was only one plug that perhaps is not working? Or do all of them drop off? That will tell us whether to chase down the mag or something coincidental.

Also, where was the engine when you removed the mag? TDC? And if so, did you install it back the same way?

Vic
 
Steve, pin the mag for right if it's on the right side. Also, I'm assuming you don't have na impulse mag, but if so, make sure you pull the prop through so the impulse fires, then go back to 25 degress and set the timing.

vic
 
It was at 25 BTDC when pulled and I set it the same. I didn't even have a chance to check EGT as I figured it's the mag since I messed with it.
 
Vic, its my understanding the L and R holes used with the pins are indicating the rotation of the mag, not the left and right use on an engine.

Check the mag data plate to determine which to use...
 
Issue Resolved

Went back and pulled the mag, re-verifed the e-gap and internal settings, then re-timed the mag on the engine and everything checks good. I believe I didn't have it correctly timed with the engine on the previous install so life is good once again!
 
You must log in or register to reply here.