The fuel damper and associated jumper hose have been a source of problems for these cars especially as they get older. The rubber hose is the most straight forward as it tends to get rock solid with age and eventually becomes a location for a fuel leak.
A failing fuel damper and/or fuel pressure regulator is a bit harder to identify. Symptoms consist of fuel in the vacuum line at the back of the damper/regulator which in severe cases can travel into the intake manifold or even the KLR vacuum line. Since the KLR line is clear you can actually spot the fuel traveling in the hose (See photo 2 below, the trapped gas is inside the circles). Others symptoms are hard to near impossible hot starts and fuel pressure loss over time at the rail causing long, lazy starts. In the case of the difficult hot starts this is likely due to the fact that as the gas migrates its way down the clear vacuum line and arrives at the KLR computer sensor it really confuses the system; when the gas eventually dries out near the computer things will appear to operate as normal for a brief period until the cycle repeats again.
Replacement on the bench if the rail has already been removed from the car can be a bit tricky since it can be a bit awkward to gently yet firmly clamp the rail to a work area to allow removal of the large nut securing the damper to the rail. Mine was particularly stuck and required me to use a chain whip vise grip on the damper to provide enough counter torque against a breaker bar.
 |
| Gas in KLR Vacuum Line (Image: 951North - Rennlist) |
No comments:
Post a Comment