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Stumble on Acceleration

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Hmmm.... the plot thickens. You already have the Petronix ignition system AND a 5-bladed fan.

If this something that just started happening in a car that has been running normally for years under these temperature conditions, I'd be tempted to favor an ignition problem (or maybe even a bad tank of gas?).
 
My BJ8 once had a stumble on acceleration, but it occurred at random times and didn't appear to be temperature-related. I'd installed suppressor plug wires a few thousand miles earlier and I think the 'spiked' terminals in the stock distributor cap did a number on them. Installed stranded copper core wires and life was good again.
 
Hi Rob,
I haven't read this entire thread so apologies if it has been mentioned. There have been posts in the past where people have insulated the fuel pump since the earlier models located the pump over the exhaust pipe. Later cars had the pump on the other side of the car.
 
Greg, That's a worthwhile suggestion. My fuel pump sits over the tail pipes so some insulation wouldn't hurt. In looking at the engine compartment this morning, I see the aftermarket fuel filter sits only about 6 inches from the number one cylinder exhaust manifold. I may insulate that also. Maybe I'll just get 12 cans of that expanding foam insulation you see in the building supply stores and fill up the entire engine bay........
 
I had this problem on my BT7. It was frozen weights under my distributer points plate. They would not expand out when I accelerated.
 
Rob Glasgow said:
Greg, That's a worthwhile suggestion. My fuel pump sits over the tail pipes so some insulation wouldn't hurt. In looking at the engine compartment this morning, I see the aftermarket fuel filter sits only about 6 inches from the number one cylinder exhaust manifold. I may insulate that also. Maybe I'll just get 12 cans of that expanding foam insulation you see in the building supply stores and fill up the entire engine bay........
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Okay, hope you aren't serious as even I know that would not be a good idea. Besides being messy, it just might crowd the engine a tad.

:lol:
 
Seriously Gentlemen - I very rarely post on this forum as for the most part is all about the internal combustion engine which for the most part has been a mystery to me. I have to say that I have learned a lot since caretaking to Agatha and I do read your posts and they are more than helpful.

Thanks!
 
judow said:
Seriously Gentlemen - I very rarely post on this forum as for the most part is all about the internal combustion engine which for the most part has been a mystery to me. I have to say that I have learned a lot since caretaking to Agatha and I do read your posts and they are more than helpful.

Thanks!
Click to expand...
My AH BJ7 is suffering the same problem. I just yesterday discovered the problem. Actually quite by accident. I was fiddling with the choke controls at the rear carb and just reached down and pushed up on the HS6 rear carb needle and it immediately smoothed out the idle and began running as new again. So now I'm planning on removeing the carb and go through the steps of re-aligning the jet needles. You can check this quite easily; first start the car and let idle, then reach down and speed up each carb individually by hand. The one thats bad will stumble and gasp, the other one in my case would just speed up, of course with just one carb you can't speed up too much but you will see a difference.
 
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