Engine smooth with timing way off?

international

#1

I’m reinstalling a distributor and having trouble getting it right. I have it in a spot now where the engine runs smoothly even though the timing light indicates the timing is not even close - like 90 degrees advanced (this is a 4 cylinder). I know how to use the timing light and it’s on the right wire. How is this possible?


#2

Is this an IH Scout 196 or 152 engine or a tractor engine? But regardless, they all fire at 0* and 180* plus the prober advance. Is the timing mark on the harmonic balancer on an outer ring pressed over a rubber bushing? If so it can slip. And does your timing light have timing advance circuit in it? You might turn the crank until ZERO is indicated, remove #1 plug and slip a piece of small diameter vacuum hose in until it contacts the piston. Then slowly turn the crank while holding the hose to feel if the indicated TDC is correct.


#3

It’s a Scout 152. My light is not a dial-back unit and the timing mark has always made sense before. The thing that changed is I went from points to electronic trigger. My theory at the moment is that the trigger I got is for a 8-cylinder by mistake instead of 4-cylinder. My tach reading looks double what it should be and I’m getting shocked easily on the cap. If I have double firings per cylinder, I wonder if the light is picking up more on the one that is off for some reason, even though they are both firing… very mysterious.


#4

The electronic trigger sounds like the most likely culprit. When the trigger fires the coil between the plug towers the air gap is very wide and spikes the coil voltage to its max and the strobe may not be recovered from the stray fire when the correct, 6,000 volt spike hits. Were you having problems with the points. They are very reliable if replaced every 10,000 miles. Those old Scouts were great. How long have you had yours?


#5

I had the occasional miss with the points, but I don’t know for sure they were the problem. The distributor needed a rebuild anyway, so I put the new trigger in to complement the MSD6 ignition I have. The MSD made a tremendous difference. I’ve had the Scout about 2 years but it’s just now starting to be reliable transportation. It didn’t run at all when I got it for $500.


#6

If you can’t get an interrupter for a 4 cylinder put a V8 cap on the distributor and ground every other cylinder at the cap. They are great old stump pullers. I enjoyed my old Bronco but it was just Fords best shot at making a hot rod Scout. Keep those wipers on the front hubs in good shape.