BENDIX TCH-001-011 User Manual

Technical Bulletin

Bulletin No: PRO-01-11 Effective Date: 7/15/78 Cancels: NA Page: 1 of 1

Subject: “Clean Engine” Tu-Flo 501 Compressor

Various engine manufacturers are promoting engines with no oil seepage. To
complement these programs certain improvements are being made in the Tu-Flo 501
compressor.

1. The hex head cap screws and lock washers used to fasten the flange adapter on
Detroit Diesel compressors will be replaced by torque screws with Dri-loc on the
threads. This will eliminate a possible seepage through the lock washer gap which
ultimately appears as a leak between the flange adapter and the crankcase. The
torque screws have been used on Cummins compressors for some time. The
difference in the bolt heads is shown in Figure 1.

2. On all flange type compressors using the sheet steel crankcase plate, a new thicker
gasket 293349 will provide a more positive oil seal.

3. The oil return holes have been sealed between crankcase and flange adapter by an
o-ring 292437 in a counter bore in the crankcase. See Figure 2. This construction
has been revised to achieve more positive sealing, using a larger section o-ring
293347 and a support bushing 293348. See Figure 3.

CAUTION: These parts are not interchangeable.