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Question
my car is shifting at a high rpm the tranny is not slipping there is enough fuild in it is there something clogged
Either of two things can cause this. First is the vacuum modulator that reads engine intake manifold vacuum to determine shift points for the transmission. There is a vacuum line from the intake manifold to the modulator and that line can be disconnected or rotted through. The modulator can be checked by connecting a hand vacuum pump to it. It should hold 20" of vacuum. If the modulator and the vacuum connections are ok the detent switch located at the carburetor could be stuck in the downshift position. The easy test for this is to disconnect the wiring from the switch and road test the car. If it shifts normally the switch is defective or out of adjustment. The last is the governor inside the transmission sticking and this will require surgery. The governor can be removed without removing the transmission on this car.
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| Comment | thank you Brad i will check those things out and go from there. | ||
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Answers by Expert:
Brad Sears
Expertise
All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.
Experience
Automotive tech instructor.
Syndicated auto columnist 1970's though the early 1990's.
Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's
TV Show "Last Chance Garage" 1980's PBS-TV syndicated.
Auto instructor for the following companies:
Fram
Autolyte
Holly
Carter
AMF
Ford Motor
University Of Conn
Blue Hills Technical School
Sugar River Technical Center
Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.
Publications
Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.
Education/Credentials
More than I care to remember.
Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.
Awards and Honors
Moto Award winner. And much more.
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