|Subject:||RE: Super X timing marks on gears ?||Date:||Thu Feb 2 19:08:46 2012|
I'll take a stab at this one. I've never been into a Super X timing chest, but they are very similar to the 61" big X, infact all the gears except idlers will interchange. The only gears with timing marks are the pinion, cam and mag gears. The idlers are not marked. Origonally, they lined up the cam and pinion gears, set the mag at the correct point, whatever that was, and then installed the idler gears. They stamped a timing mark in the case that corresponded with the mark on the mag gear. So look for a small line stamped inside the case adjacent to the mag gear, usually around 4:00 I believe. It looks like they used a small chisel and stamped in the backside of the case.
Unless you know for a fact that all the internals and the mag came from the factory in that engine, I would disregard the mag timing mark and work it out on your own. Lign up the cam and pinion gear marks. Set the timing on BOTH cylinders, not just one. I set my 19 X at 7/16" before TDC. Locate that spot on one cylinder and rotate the mag until the points just begin to open for that cylinder. Install the idler gears and rotate the engine around to the other cylinder and check the timing. Be sure to have all the slack out of the gear train when checking the timing. You may find that you have the wrong cam lobe in the mag timed to the wrong cylinder, so try again..... Careful checking should get you close. Now fine tune that setting so both cylinders fire exactly the same amount BTDC. If one cylinder is on the money, good! Then if the second cylinder is firing early, you need to move the mag gear 1 tooth back and time to the second cylinder, then check the first, which should now be firing late. If you can't get things dialed in by moving 1 tooth at a time, then get one cylinder set right on the money with the other cylinder firing a bit early. Dress the leading edge of the cam that corresponds to the cylinder that is firing too early. Check often and carefully. Removing a few thousandths on the cam changes the timing quite a bit. You can slowly dial the timing in so they are even. I was able to get both cylinders on the 19X timed to within .007" TDC of eacjh other. I used a dremel tool with a small barrel sander to remove large amounts, then an emery board for the final dressing.
This is a slow and frustrating procedure, but well worth it! When you get it right, that thing will run better at all speeds and idle down very slowly and evenly.
Once that's done, be sure the wires are going to the right cylinders! For Bosch magnetos, the wire coming from the front pickup goes to the front cylinder, rear exiting wire to the rear cylinder. Splitdorf mags are the opposite, front wire to the rear cylinder, rear exiting wire to the front cylinder. You can also remove the high tension pick up from the (Bosch) mag and look inside to be sure that the brass section of the slip ring is going to the correct cylinder at the right time.
When you're sure you have it right, make some kind of marks inside the timing chest so next time it comes apart, you don't have to go through all this again. An easy way is to paint marks on all the gears, start with the timing marks on the cam and pinion.
Clear as mud!!!???I hope this helps out.
----- ORIGINAL MESSAGE FOLLOWS -----
i am completing a rebuild motor of a 1930 Super X and have a question on how the gears are put back in correct order ?
There are no timing marks on these gears and fortunately i have found no related topics in the board.
Also the Super X manual doesn´t show clearly the correct reassembly.
Can anyone please kindly help me ?