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Miss Agatha

jlaird

Great Pumpkin
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has a high speed miss or stumble.

Is not the carbs I think as the plugs are just fine. Kind of wonder if I have a valve that needs adjusted or is sticking, heard a bit of noise up there like an exhaust leak when it was doing it.

Anyway, fun and games.


Was on the way back from a show and shine at one of the local mauls that sponcers our big anual show. We had about 30 cars on their main street. Was a good time for all.

Photos later.
 
You know, I just looked at my plugs again. Numbers 1,2 and 4 are just lovely, number 3 is a bit black like it has not been fireing properly. Now that can not be carbs because of the intake ports 3 and 4 must be the same fuel wise.

Hmmm, wonder if I have one of those bad rotors that is not allowing that plug to fire correctly at high speed when compression is up high and operation is fast.

Hmmmm.
 
Or, put another way. Plugs 2 and 3 should be the same if the rings and valves are ok as they are both fed the same fuel through a joint port. If they both also have good fire they will look the same.
 
What is high speed?

How much axial play is there in your distributor shaft?

I assume you've set the valve clearances and point gap correctly. And the plug gaps are fine.
 
Going to check all that in the morning Trevor.

Yep, and it is prob time to have Jeff rework this old dizzy as well, no excuse sir, I just been putting it off.

High speed is 60 on the highway. I never do that, I run it out to 5K in the gears though and have not noticed the prob before, however it may have been there since I put her together. First time I have done any highwiay speed for more than a min or so.

Morning is valves, points, and plugs then a test run just to check. I know the timeing is spot on, well will check that as well. Heck I trust nothing at this point.
 
Follow up.

Points were set at or slipped to .003. Back to .015 now. Have not tested yet but bet that does it.


Another one of those dumb things where I did not get the screw tight.
 
Learned something, just goes to show ya.

If the points are too close, tight, the engine will not idle properly. As you remember I could not get idle down to 850, well I can now.

Need to take a test drive but I think I need to work on mixture as well as it seems to be different with the proper spark.

See, you can teach old dogs new tricks.
 
I don't know, Jack...sometimes with old dogs, it's not necessarily teaching a new trick so much as REMEMBERING an old one!! :wink: :jester:
 
Hehe, just got back from a short run. Miss Agatha is as good as it gets, idle to 5500 RPM smooth and happy. Plugs a nice tan, all of them.
 
Way to go Jack. I learned something from your description of the symptoms (plus/points..etc) and the cure.

Oh...at what age do you become an old dog?
 
I will be 70 in a couple of weeks, I am sure that makes me an old dog.
 
You're an old dog when you stop feeling like a puppy any more!! :devilgrin:
 
Golly knows I don't feel like a puppy but I like to keep an eye on stuff.
 
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