Breakdown Information
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Forum Discussion
See previous post of 2/7/04
UPDATE:
Coach wouldn't start two days ago. Temp had been in single digits again, but slightly above freezing.... snow still standing.
1) Had noticed considerable sucking sound and "beer canning" sound of fuel tank when re-fueling, but wrote it off as just normal for non-vented tank. (I just bought this coach, so had no history to compare it to)
2) Drained Fuel/Water Filter (FS1000) and had long sucking sound before fuel drained. (Very little water)
3) Started engine, but it quit after running about 15 seconds. Would not start thereafter. Spent over 3 hrs trying to troubleshoot until batteries drained and had to call tow service.
4) Cummins service found fuel tank vent plugged. Vent line (1/2" hose) runs down below compartment (Curbside) where it is vulnerable to road debris, water, snow, etc. Engine started and no other problems found.
5) Theory was that the vacuum formed in fuel tank from plugged vent allowed air to be drawn into fuel filter when petcock opened to drain water. This allowed all the fuel in the line to be sucked back into the fuel tank, leaving the line full of air. Unable to prime the engine (Winn/Racor electronic air purge was bypassed due to suspect in former problems) so the engine would not start, and batteries ran down in unsuccessful attempt to draw fuel.
Monaco tech service says they have very few reports of this causing problem to other Navigator owners and continue to use this same venting on current models. They offered no solution, and have made no re-design of venting system. Comment was made that the fuel vent line was more than likely plugged when delivered by dealer and has been the cause for all four breakdowns.
Cummins technician suggests removing fuel cap before draining FS1000 in the future, and if difficulty starting engine, especially if vacuum present at fuel cap.
I re-installed Winn/Racor system (after having disassembled unit entirely and establishing the fact that there was no obstruction to fuel flow). Air purged using electronic panel (fuel line opened for this procedure) and engine started with no problem.
From now on, any vacuum found when removing fuel cap will be investigated.
NOTE: For owners of older model coaches with Winn/Racor fuel filter system requiring Racor 200200 30-micron filter, this filter is obsolete and supplies are almost (if not) gone. An upgrade kit is available to replace this with another filter/water separator bowl that is readily available. You can specify an aluminum or plastic see-thru bowl. The spin-on filter can be separated from the bowl and replaced at a much lower cost than the 200200, so the recovery of the upgrade kit cost is quick.
UPDATE:
Coach wouldn't start two days ago. Temp had been in single digits again, but slightly above freezing.... snow still standing.
1) Had noticed considerable sucking sound and "beer canning" sound of fuel tank when re-fueling, but wrote it off as just normal for non-vented tank. (I just bought this coach, so had no history to compare it to)
2) Drained Fuel/Water Filter (FS1000) and had long sucking sound before fuel drained. (Very little water)
3) Started engine, but it quit after running about 15 seconds. Would not start thereafter. Spent over 3 hrs trying to troubleshoot until batteries drained and had to call tow service.
4) Cummins service found fuel tank vent plugged. Vent line (1/2" hose) runs down below compartment (Curbside) where it is vulnerable to road debris, water, snow, etc. Engine started and no other problems found.
5) Theory was that the vacuum formed in fuel tank from plugged vent allowed air to be drawn into fuel filter when petcock opened to drain water. This allowed all the fuel in the line to be sucked back into the fuel tank, leaving the line full of air. Unable to prime the engine (Winn/Racor electronic air purge was bypassed due to suspect in former problems) so the engine would not start, and batteries ran down in unsuccessful attempt to draw fuel.
Monaco tech service says they have very few reports of this causing problem to other Navigator owners and continue to use this same venting on current models. They offered no solution, and have made no re-design of venting system. Comment was made that the fuel vent line was more than likely plugged when delivered by dealer and has been the cause for all four breakdowns.
Cummins technician suggests removing fuel cap before draining FS1000 in the future, and if difficulty starting engine, especially if vacuum present at fuel cap.
I re-installed Winn/Racor system (after having disassembled unit entirely and establishing the fact that there was no obstruction to fuel flow). Air purged using electronic panel (fuel line opened for this procedure) and engine started with no problem.
From now on, any vacuum found when removing fuel cap will be investigated.
NOTE: For owners of older model coaches with Winn/Racor fuel filter system requiring Racor 200200 30-micron filter, this filter is obsolete and supplies are almost (if not) gone. An upgrade kit is available to replace this with another filter/water separator bowl that is readily available. You can specify an aluminum or plastic see-thru bowl. The spin-on filter can be separated from the bowl and replaced at a much lower cost than the 200200, so the recovery of the upgrade kit cost is quick.
