Missing under load

[woodchk502]

So I'm trying to get my pile back abusable again, and it has a miss under a load only. I thought I had a bad wire so I put together one of my good Taylor wires
Seemed to help so I just bought all new 8mm wires. Problem solved... Or not, again idled well but missed under a load. So I investigated the cap and rotor, and found the center pin in the cap broken. Replaced it and adjusted timing to 8* and it still misses under a load. In neutral it will rev fine (for a worn out small block). Thoughts. It has been sitting for a while, it is a little low on old fuel so I added about 3-4 gallons (all I had) of fresh to the tank. Plugs look good as well, they are 3-4 years old but have less than a thousand miles on them. Thought???

 

[big dan]

Vacuum leak?

I'm not very good at diagnosing miss under load situations. My scout was doing it and after trying numerous things I ended up putting in new distributor, new wires, new plugs, new intake gaskets, new vacuum lines and a new base plate on my propane mixer. Not sure which one got it but it's fixed

 

[woodchk502]

Vacuum leak?

I'm not very good at diagnosing miss under load situations. My scout was doing it and after trying numerous things I ended up putting in new distributor, new wires, new plugs, new intake gaskets, new vacuum lines and a new base plate on my propane mixer. Not sure which one got it but it's fixed

Would a vacuum leak only cause miss under load? The cap and rotor are not new, but they were purchased at the same time as the plugs, so they have very little mileage on them.

 

[ryoken]

9 out of 10 misses are ign...


if the cylinders make good compression, it'll be in the cap/rotor, wires or plugs themselves... plugs are $25... cheap... cap/rotor, same.... just cuz it's low mileage, doesn't mean squat.. I've seen caps f*ck up in months with no signs of issues...

 

[woodchk502]

9 out of 10 misses are ign...


if the cylinders make good compression, it'll be in the cap/rotor, wires or plugs themselves... plugs are $25... cheap... cap/rotor, same.... just cuz it's low mileage, doesn't mean squat.. I've seen caps f*ck up in months with no signs of issues...

Ive Been dreading checking compression. But rather than replace cap, rotor And plugs, I guess I'll do it in the morning.

Thanks,
Jim

 

[Kain]

when you put the button in the cap do you put it under the rubber or over?