Hummer H1 Service Manual page 165

3-28 Fuel, Emissions, and Exhaust
FUEL LEVEL TRANSMITTER AND TANK ACCESS
PLATE SERVICE
Removal
1. Remove screws, lockwashers and fuel level transmitter
from tank access plate (Figures 3-34 and 3-35).
2. Remove locknuts, washers, access plate and gasket from
tank.
3. Remove access plate retainer and O-rings from tank.
Discard O-rings.
Check fuel level transmitter operation as follows:
1. Hold transmitter in the upright or empty position
(Figure 3-36).
2. Using an ohmmeter, check resistance value at terminals.
Resistance should be 268 ± 20W.
3. Hold transmitter in the inverted position simulating a full
tank. Resistance should fall to 19.3 ± 8W.
LOCKWASHER
FLATWASHER
TRANSMITTER
Figure 3-36: Fuel Level Transmitter in
Upright or Empty Position
Installation
CAUTION: Do not overtighten access plate or transmitter fas-
teners. Gasket damage and improper sealing could result.
1. Thoroughly clean all gasket surfaces.
2. Place new O-rings on access plate retainer studs and
position access plate retainer in tank (Figures 3-34
and 3-35).
3. Set gasket and access plate over studs and onto tank.
4. Apply liquid teflon thread sealant to studs and loosely
install washers and locknuts until no clearance exists
between access plate, gasket and tank.
5. Snug access plate locknuts in small increments and in a
systematic circular pattern. Tighten locknuts until gasket
bulges or until maximum torque of 72 lb-in. is obtained.
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SCREW
GASKET
6. Apply liquid teflon thread sealant to transmitter mounting
screws.
7. Secure gasket and transmitter to access plate using same
method as indicated for access plate above.
8. Cap all tank fittings and perform leak check. Apply leak
check solution or soapy water around access plate and
transmitter gaskets and fasteners. Pump 3 p.s.i. of
compressed air into tank and verify absence of leaks.
Quick Connect Fittings
Quick connect fittings are used at the main tank fuel tubes,
auxiliary tank fuel tubes, and at the fuel tank selector valve.
Two types of fittings are used. One type is an all plastic push
on style with removable retainer. The second style is a metal,
one-piece fitting with an internal tension clip to retain it. The
plastic fitting retainer only requires a screwdriver and needle-
nose pliers to remove. The metal fitting requires a release tool,
such as J–37088-A, in order to disconnect it.
The metal fittings are used at the main tank. The plastic, two-
piece fittings are used at the auxiliary tank and fuel selector valve.
Metal Fittings
1. To disconnect, slide the release tool onto the line and into
the fitting.
2. Press the tool inward to unseat the internal clip and pull
the line off the fuel tube.
3. To reconnect, just push the fitting onto the line until it
snaps or clicks into place.
4. Pull on the fitting afterward to verify proper seating.
Plastic Fittings
1. To disconnect, raise the retainer tab with a small flat blade
screwdriver and remove the retainer with needlenose pliers.
2. To reconnect, push the fitting onto the tube, insert the
retainer through the fitting sides, and seat it firmly.
3. Be sure the retainer seats behind the fuel tube flange.
4. Pull on the fitting afterward to verify proper seating.
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