| rpms at 850 range with adv. timing 16 tdc/ 700 at 10 degrees [message #264860] |
Sun, 26 October 2014 15:13  |
budworks521
Messages: 137
Registered: October 2013
Location: Grand Rapids MI 1974 Pain...
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I finally bought a tach meter and started off with my distributor slightly advanced to 15/16 tdc. My vac gauge reads a steady 18 inches for quite awhile. My best readings on the vac gauge was with the timing advanced at start up. I decided to check rpms and they were in the 837/857 range. I then moved the distributor closer to 10/12 degrees tdc and my rpms decreased to 710 ranges. My two idle screws didn't make much of a difference when opened a 1/4 turn. The engine runs fine for awhile and then slowly fades 2/3 inches. It isn't stalling anymore but my choke seems to take quite some time to fully open. If I throttle the engine it drops 2-4 inches and then shoots to 25 or so then a slight drop to 15/14 and wavers back and forth. I was wondering if running the engine without a full 90 degrees on the choke would cause these symptoms and a if the symptoms are more in line with a restricted muffler. I see carbon sooty deposits on outside of muffler. Though the exhaust pushes fine at tailpipe. Steady drum. I plan on buying an electric choke soon but was wondering if a bad muffler would cause a great reading on the vac gauge to start and then the gauge acts differently as the engine runs (back pressure and lower readings)??? Any and all comments from previous experiences with this vac reading scenario would be great. Thanks gentlemen..
1974 Painted Desert
455 upper half rebuild
constant project inexperienced mechanic
Grand Rapids Mi
Always trying to learn
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