BENDIX TCH-011-001 User Manual

Technical Bulletin

Bulletin No.: PRO-11-01 Effective Date: 9/15/78 Cancels: PRO-11-01 dated 5/3/76 Page: 1 of 3

Subject: AH-4 Air-Over-Hydraulic Intensifier

Ref: Figures 1, 2, 3, 4, 5, and 6
The AH-4 Air-Over-Hydraulic Intensifiers have been in use for approximately three years

and service requirements are starting to materialize.
The AH-4 uses one basic master cylinder design in combination with either a type 50,

type 36 or a type 30 Rotochamber giving a pressure ratio of 23.5:1, 17:1 or 13.5:1
respectively. Master cylinder volume for type 50 and 36 is 6 inch
Cylinder Volume is 4.8 inch

Hydraulic fluid is supplied to the master cylinder from either a direct or a remote
mounted reservoir. Most AH-4’s use hydraulic brake fluid; however, certain models,
equipped with different seals, use mineral type hydraulic oil.

Most assemblies are equipped with a stroke warning switch which will close upon
excessive stroke, lighting a light at the operator’s station.

3

.

3;

for type 30 Master

The Rotochambers normally breathe from the non-pressure area through four openings
between the head and shell; however, certain models designed for dusty operating
conditions are designed with a close fit between head and shell and breathe through an
air filter in the head.

Mounting brackets are normally supplied at each end of the rotochamber for either right
of left-hand mounting and the high pressure hydraulic connection may be on either the
right or left side of the master cylinder.

Figure 1 is a cross section of an assembly with integral reservoir.
Figure 2 shows a section of a 3/8” NPT adapter for connecting a remote

reservoir.
Figure 3 shows an adapter with ¼” flared tube seat.
Figure 4 shows an end view of a master cylinder with left-hand mounting bracket

and right-hand hydraulic delivery.
Figure 5 shows a cross section of the dust-resistant version with an air filter for

breathing non-pressure air.
Figure 6 is a chart of the most popular Pc. Nos. indicating their configuration

reference the foregoing figures and also vehicles on which most of the OEM
installations have been made.

Service Data for AH-4’s is available in SD-11-1 publication.
Maintenance kits for the master cylinder are available under Pc. No. 289286 for brake

fluid and No. 289287 for mineral oil.