| Engine misses on acceleration [message #343406] |
Fri, 17 May 2019 05:05  |
CLawson
Messages: 11
Registered: July 2016
Location: Wellington, OH
Karma:
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Junior Member |
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I bought my 1975 Glenbrook about 2 years ago and have been working on it off and on.
The coach has always had poor acceleration and a very heavy thud-thud-thud when accelerating.
However the engine idles very smoothly.
Olds 455 with carb and HEI ignition.
It has 150,000 miles but the compression checks fairly well, most between 160 to 170 with one cylinder at 150.
The Rochester carb has been rebuilt
New plugs, cap, and rotor
Timing reset
New fuel filters through out
New mechanical fuel pump
The wires show no signs of leakage or sparking in the dark but I am thinking to replace them as a next step.
Also the vacuum lines have been replaced as needed but I am planning to replace all to eliminate that.
The vacuum advance moves but takes a lot of force to nudge it with a screwdriver. Should it be that stiff?
I would appreciate any and all suggestions to diagnose.
thanks! Cary
Cary Lawson
1975 Glenbrook, 455, carb, HEI
Wellington, Ohio
Cary Lawson
1975 Glenbrook, 455, Rochester carb
Wellington, Ohio
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