Manifold bolt FYI

Information on some common auto air conditioning topics.
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Manifold bolt FYI

Postby kell490 » Wed Apr 04, 2018 10:55 pm

I got a new compressor, accumulator, and condenser for my 99 F-150 5.4L pickup After getting everything installed I could not get a vacuum to pull it was like open line pulling air. I disconnected different parts of the hoses put my finger over the ends worked my way down to the compressor manifold which is under the engine passenger side not in a easy place to reach. I pull the manifold off and cover it with my fingers vacuum starts to pull I know it's either the compressor is bad or the connection.

The new compressor came with the plastic block over the ports where the manifold bolts up with one bolt in the middle. I got the bright idea to use the bolt that came with the plug it was brand new nice looking flange bolt just like the rust colored original. What happend was the bolt which was new that came with the compressor is slightly longer then the original bolt it was bottoming out the hole on the compressor and not putting enough force on it to seal the o-rings. You could not tell even if you moved the aluminum lines around but was just enough not to allow a good seal. After swapping back to the original bolt pulled 30 inches of vacuum with no issues. That added 3 hours extra to my fun tonight along with thinking my vacuum pump was out of oil over filled it sprayed all over the place it was dark I could not see the sight glass too well.

It was fun night of AC repair I remind myself to never buy a car with the compressor at the bottom of the engine and always use the original parts

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