Ed, going into a filter setup that one would think fluid matters not at location level and kinda
buying into that idea. here is where the problem starting, low power. In most cases what causes
low power is low fuel pressure. How do we determine low fuel pressure is start at fuel tank in
front of motorhome and work back to engine fuel transfer pump. This operation is using a clear
line tied in after the racor filter start engine to see if clear line will fill with diesel fuel ( any thing
Located on suction side of cat fuel transfer cannot have any air ) starting engine let run for 10
minutes at low idle, medium idle and high idle. Again cannot have any air present in suction side
of transfer pump. Note:pulling fuel through Racor filter and seeing foam and bubbles in clear
line just before cat transfer pump one would think there is a air leak. Connect direct fuel line
from fuel tank leaving out Racor filter,same test this time no air or bubbles. Going to next level
clear line the return line on engine to fuel tank. With Racor filter connected and clear line connect
at cat transfer pump doing same test ( note cannot have any air present on return line back to tank.)
what were the results with test number one, clear line looked like foam inside and little fuel at
meduim idle and at high idle. Removed Racor filter and preformed test without filter, return clear
line full of fuel no bubbles or foam. What does this tell us with air in the return line to fuel tank.
It tell us we have very low fuel ,pressure going through the head and injectors which is causing
Low power. So nobody misunderstood about filter setup which happened to be Racor filter setup.
There is a problem that happened at present 6 times since the first of the year. Problem compounded
when party's involved had motorhome at repair shops and lots of money spent replacing parts.
After high priced repairs, low power still present because the root of the problem was before the engine. Sorry cannot sugar coat the problem because the problem is the filter setup ( racor ). With
this said and talking with Parker Hannifin earlier, the answer to problem with any Diesel engines
There cannot be any air present on a suction side of a cat fuel transfer pump. The same thing with a fuel return line back to tank ( no air can be present ) again one filter setup maybe yes but five
more of the same the answer is no. Dave Atherton Retired Cat Mechanic