8n miss

I've been reading on mostly this and a few other forums for almost a week now and I can't figure out what my problem is so I've decided to ask the experts. I have a late 8n (side distributor)zenith carb, 12v with full 12v coil(says it has internal resistor) 437 AL plug. Coil and plugs are new as is points condesor plug wires (copper)rotor button and distributor cap. Fuel is new and clean and flow good to carb. Carb is adjusted by instructions I found online for the zenith. Timing is set with a light, and firing order is correct. The tractor starts good, barely have to touch the starter. Its seems to run well for a minute or so, but when I throttle up it gets a miss. It will pull its own weight ok in 1 2 3 gear, but doesn't want to go in 4th or with a load. The miss does persist if I throttle back down, but does not seem to be as bad. I've been over the points with a feeler gauge several times and even took some 150grit to them (lightly) even tho they are new. The only thing I can think of is that the distributor bushings are worn. If I put my finger on the cam with the rotor off I can move it but only a little (maybe .010)and it doesn't seem to move freely. Any help would be great, I'm lost...

clip under the rotor in place and rotor fit tight and not move?

advance mechanism in good order?

The rotor seems to fit tight, I'm not sure about a clip. The springs on the weights are a little light, but everything moves freely.

how about the dizzy shaft itself.. much play?

I can turn it back a forth a little. I"m at work so I"m having to go off of memory. It seemed like it turned more than I thought it should, but not enough to knock it out of time by more than a degree or two. You can wobble the shaft side to side, appling force to the cam, but not by very much and it doesn"t seem like it wants to move. I"m not sure if there is enough play to be causing my problems or not.

Tim23 ,Is there any side play in the distributor shaft? That could cause a miss.

Make sure you have the cip. Will note run right without it.

This is the clip the guys mentioned. Link
It goes on the distributor shaft under the rotor.
Was this problem there before you replaced all the parts?
Do all the plugs look that same when you take them out?
It's not uncommon to get a bad plug or have a bad connection on a plug wire.

I don't think it has that clip on it. I will check in the morning. The problem was there from the begining, the tractor was not running when I bought it. Its one of those "it ran last year" deals. I started by replacing the plugs and doing some work to the fuel system. Once I got fuel going and replaced the plugs condesor and points it started right up. Everything else I replaced was to get that last little miss out and get the power up where it should be so I can do some work. As far as the plugs go, I haven't had them out since I put them in 5 days ago with the exception of #1 and it looked fine. I did disconnect each plug wire while running and there was a noticable drop with each one. I don't know if this means anything or not, but #2 did shock the p*** out of me, where 3 and 4 did not.

Tim........from yer description, even though you replace yer sparkie wires, (and gott shocked, no surprize there) recheck yer firing order; 1,2,4,3, CCW. The 5-nipple sidemount can be confusing. These N-Engines are SOOOooo GOOOoood that they will start and run on just 2-sparkies but won't have enny power just as you complain. ........Dell, yer self-appointed sparkie-meister

Thankyou everyone for your help. I went out this morning to check up on the things mentioned yesterday and found very little play in the distributor shaft. I also rechecked the firing order, it is 1243 ccw. I think my problem as mentioned yesterday, is there is no clip on the underside of the rotor. I looked around and didn't find it in the old parts that came off(I don't throw anything away). Decided to go by TSC on the way in to work and they didn't have one with their ignition stuff. I was wondering if I could use a piece of tape to wedge it in tight, or if anyone had an idea about what I could do to get it running quick. I would really like to mow tomorrow or Friday before it rains again.

Go to your local Case New Holland dealer and as for the New Holland tune-up kit for the sidemount and it should (as of last year) have the clip you are looking for. And the points are pretty good as well. The AL 7 plugs have caused some heartburn for members of the forum however. I have used them in a show tractor, but I can't tell you how good they are under load. I don't remember how much the kit cost.