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Jack Tietjen

Vacuum modulator install.

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I just installed a vacuum modulator on my 1965 Buick Riv. It was shifting late and hard. When I pulled the old one out, it puked tranny fluid all over the place. It's been years since I put one in. I never put one in a early Riviera, but is it normal to get tranny fluid pouring out of the modulator hole when removing it? Thanks.

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  YES.  About 1-1 1/2 quarts will come out give or take.   IF the modulator doesn't fix the problem the next step is the governor.

It could also be the governor.  Remove 4 bolts from the cover on the right rear of the trans.

There will be a gasket there. Best if you get one beforehand as more than likely it's leaking & may tear/rip when you take the cover off. NO fluid should come out, or very little.

 The governor will pull right out with a small counter clockwise twist.  IF it doesn't come out twist it clockwise. Now look inside at the little valve. That should move up & down when you grab the two weights, IF you know what your looking at. Familiarize yourself by looking at a picture in the manual. Now this valve is very small & kinda hard to see because it's inside & only moves a slight amount.  IF the valve doesn't move the governor is sticking & causing your problem because of debris.  IF you aven't done this before refer to the chassis manual.  In reality it's really simple to take apart & clean.



Tom T.

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