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Irregular Heartbeat - SOLVED!!

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Geeze Louise! I wrote such a nice long-winded note to this when I posted it, I don't know why it didn't go, but at least the icon and subject line made it! /ubbthreads/images/graemlins/confused.gif

Anyway, the final solution was a hidden airleak in the rubber cap I was using over the intake manifold's pollution control stem. This engine is from a 1970 Midget, just after they started requiring air pollution control. The PO had removed the system, so when I rebuilt it, I used a heavy rubber cap and a hose clamp to seal off the intake manifold stem where the pollution control hose came in from the exhaust side. I'm only guessing, but I think that during the autocross I ran on August 1st (95F), things got hot enough under the hood, and my heavy foot, created enough vacuum at the intake to actually suck a hole in the softened rubber cap.

I would have never seen this if I hadn't had a club member over to offer his help solving the problem. While he was bent over the carbs using a synch tool, I was in the appropriate LBC prayer position (kneeling in front of the radiator looking quizzically at the engine). My eye happened to glance down the to the area of the valve cover and coolant return pipe. I noticed something that looked like a hole in the bottom of the rubber stem cap. I put my finger over it with the engine running and it immediately smoothed out and purred.

The ironic thing is that I would have never seen this hole in any other postion than where I was at, since it was on the bottom of the cap and "unseeable" from above. I have since placed a permanent brass plug in the stem pipe, sealing it with my favorite repair tool: JB Weld. I am back on the road again.

/ubbthreads/images/graemlins/cheers.gif
 
I have edited my original note, since what I wrote apparently didn't "stick". Please see the first note for the solution.

Tim C.
 
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