Fuel Hose Clamps
Fuel Hose Clamps are a special type of hose clamp designed for high pressure fuel injection hose. The Z32, during its lifetime, utilized two different types.
Versions
- 1990-1996 (Shown Above): This type of hose clamps used a t-bolt style design that distributes even clamping pressure all the way around the hose. It used a philips-head screw to tighten or loosen.
- 1997+ (Shown Below): This type used a simpler dual-layer spring-clamp design that exerts a constant amount of force at all times. Nissan's entire product range gradually transitioned to this type starting in 1997.
Worm Gear Clamps
Owners should avoid using worm gear-style clamps on fuel injection hose, as the grooves in the band can chew into the hose material and cause leaks. Further, most aren't designed to hold the amount of tension generally required to form a good seal, and tightening them down enough to make a seal usually damages the hose.
Problems and Leakage
With traditional hose clamps, including the OEM Nissan style, periodic re-tightening is required. This is because over time, especially during cold weather, the rubber hose shrinks gradually. As the hose shrinks, the tension exerted by the clamp is lessened, and eventually this progresses to a point where a fuel leak forms. For this reason, Z32 owners often notice a fuel smell during colder weather. This becomes extremely problematic with the short fuel hose joining the two halves of the fuel rail together, as its clamps are almost completely inaccessible without removal of the intake manifold. This can be extremely dangerous if left unchecked.
In 1997, Nissan gradually began switching to a new spring clamp of fuel hose clamp (as shown above). Aside from being cheaper (List price of $1.94 vs $2.60+), this clamp is able to the proper amount of tension on the hose at all times, even if the hose shrinks.
The Nissan part number for this new clamp is 16439-16E0A.
Bernie's post about these on TT.net here.
