SERVICING THE HYDROVAC
(First Series)

There are two basic types of Hydrovac units: the first series, in which the control valve is separate from the hydraulic slave cylinder and located on the opposite end of the power cylinder; the second series, in which the control valve is integral with the hydraulic slave cylinder.

IDENTIFICATION DATA
(First Series)

Part Nos.	Models
371730	H-66-3.3
371830	H-76-4
*372290	H-66-3.3
372428	H-76-4
373380	H-66-3.3
373500	H-66-3.3

*For Chevrolet only, drilled piston.

Identification of a Hydrovac unit is made Possible by a small metal tag attached to the clamp which holds the hydraulic jumper line at the center plate. This tag carries both the part and model number. These numbers are needed to determine the proper Repair Kit to use when servicing a Hydrovac.

No attempt should be made to service a Hydrovac without first obtaining the Proper R-K Repair Kit which contains all the necessary parts that should be used when reassembling the unit. See page 25 for First Series Hydrovac R-K Kits.

TECHNICAL AND APPLICATION DATA
(First Series)

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