I own a 1998 Monaco Safari Trek motor home -- a Class A (boxy structure), gasoline-powered, recreational vehicle. I could go on for pages about all the little things that went into (or didn't go into) the construction of this vehicle. My friends joke that I am the only person they know who would disassemble a new motor home in order to fix it.
I went through a rough period where the engine would just quit, usually at very inopportune times. Or, the vehicle would start running lean, forcing the computer into an open-loop mode to keep the engine running. I think I fried a catalytic converter running it that way once.
The vehicle is equipped with OBDII (check engine codes), but it doesn't provide fuel pressure as a reading. The symptoms pointed to a plugged fuel filter or a bad fuel pump.
The fuel pump is located inside the gas tank, so it's not the easiest thing to service. I had it replaced once. I went to fill up with gas, only to have the gas start gushing out from the top of the tank. I guess it was a trick to get the gasket correctly placed for the pump, and you didn't know it was incorrectly placed until you tried filling the tank. So now I had a full tank (60 gallons) that had to be drained so I could work on the pump.
Worst of all, the fuel filter is buried up inside a chassis rail, right above a 12V DC distribution panel that has lots of hot, exposed cable ends. It's hard to reach, and there is very little space to work. There is barely room to get a wrench onto the nuts holding the fuel filter canister. Plus, when you loosen the filter, gas flows out over the power cables. It would only take a slip of the wrench to short out one of the exposed connections, sparking the gas into a nice little fire. There is no way to cut off the power short of disconnecting all the batteries and covering the solar panel with a blanket.
This was the worst possible place they could have located the fuel filter. Definitely Made by Monkeys.
This entry was submitted by David Lippincott and edited by Rob Spiegel.
Tell us your experiences with Monkey-designed products. Send stories to Rob Spiegel for Made by Monkeys.
I agree with the authors comments that this was not a good location for a Load Center or Distribution Panel. But on the same note anyone dealing with Electricity or anything flamable/combustable regardless of proximity to said flamable/combustable materials the Batery or electrical source should be disconnected prior to initiating work.
Well, I've been a mechanic on various motor veficles and stationary machinery for over 40 years. The first thing you do is usually dis-connect all power sources. Just about every fuel injected vehicle has the filter in the tank, ahead of the pump.
Currently I drive a 1999 Dodge 1500 Ramvan and have had to drop the 32 gallon tank. The filter is right there at the $400 pump assembly, and helps keep the motor working a long time, as the fuel usually flows right through the electric motor.
After dropping the tank for a no-fuel pressure problem, it turned out the MCU wasn't turning on the pump at all, so I had to replace that $680 MCU .
If ethanol is eating your weedwhacker, just go buy some non-ox fuel. even if it's 50 cent's a gallon more... and you burn 30 gallons all summer, that's 15 bucks to keep things running. I run non-ox in my 1971 snowblower, my 1990 motorcycle, and ALL my mowers regardless of age. it's a damn bargain, period. Your state fuel retailers association has a list published somewhere online that'll tell you where all the non-ox gas can be purchased.
I've had some intersting experiences with fuel systems on vehicles.
The 1987 Ford F150 I bought used a few years back has two gas tanks, each with a pump built in. One of the pumps leaks when it runs - I suspect the gasket, but since the tank needs to be removed (or the truck bed....) to get at the pump, I haven't bothered yet, I just use the other tank (there's a switch to select which tank feeds the engine, and the switch operates one or the other fuel pump.
Then, the 1978 Jeep CJ-5 which I use to plow my driveway (and that's all, because there's no way I could get that thing road-legal any more) has a bug (or feature; I don't know which) in the Carburetor that allows the float bowl to drain when the engine isn't running. I suspect it drains into the intake manifold, but I never could figure it out - rebuilt the carb and that didn't solve the problem, which leads me to the "feature, not a bug" opinion. And thinking that it might be leaking back down through the fuel pump was not solved with a new fuel pump (mechanical). Anyway, if you park the jeep and come back a day or so later, you have to crank the engine for several minutes in order to get the float bowl filled and the carb woking properly to start. This is hard on the battery (which also runs the plow lift pump, so I prefer to be gentle with the battery) and the starter motor. I've been using starting fluid (ether) to start the engine; once the engine gets up to speed, the mechanical fuel pump quickly fills the float bowl, but ether is hard on the engine and not recommended as a general practice. I'm about to install an in-line electric fuel pump; that should allow me to fill the float bowl before engaging the starter.
And then there's the problem of using 10% ethanol gasoline on this old equipment which may have seals and other rubber parts which the ethanol attacks. The manual priming bulbs on my lawnmowers, etc. are some sort of rubber which doesn't like ethanol; they give out after a few years. After a few go-rounds of this, the other sealing parts start to go and the lawnmower makes the final trip to the dump....
Constitution man, one cheap and quick fix is to add a manual pushbutton to allow for running the pump prior to cranking the engine. But you would need to use a button good for the load, and be sure to protect the wires from damage that could cause a short circuit. And use a momentary switch so that the pump does not stay running if the engine dies for whatever reason.
About the filter near the power distribution block: ABSOLUTELY be sure to disconnect the battery that feeds that block prior to any work in the area. I would bypas that filter and install an aftermarket filter in a location that was easier to work on.
For the fuel lines that need to be connected above the tank, next time disconnect them at the other end of the rubber tube, which is probably more accessable.
And, the genius monkeys that designed the model 1500 Dodge pickup also put a quirky check valve in there with the filter, gauge sender and pump unit... mine [1999 model] leaks back after shutdown. you can hear it bubbling on a quiet day. BUT, the 1998 model had a pressure switch on the startup relay so the fuel pump would run until adequate line pressure was achieved. But, to SAVE MONEY for 1999, they dumped the pressure switch and opted for a 2-second timer relay. Problem is that it needs 4-6 seconds to fully charge the empty line so I must cycle the key 3 times THEN crank the starter... or the engine won't start. P I T A ! ! Anyone know a quick fix?
Regarding the spark hazard, it runs in my mind that when I've replaced fuel filters before (on two different GM passenger vehicles, filter not in the tank), the instructions always included a step to disconnect the battery? As you say, that would remove the spark hazard.
Fuel pump cooling is an added attraction to mounting it submerged in liquid hydrocarbon. You also get the benefit of ensuring pump priming and you can add other reliability issues like putting the fuel level sender on it as well. Doesn't mean its smart to be there in terms of maintenance and reliability. Just cheaper and seems to be a uncoordinated conspiracy by all the vehicle manufacturers.
On the issue of the fuel filter over the 12 V connection bus, I'd take off my service/support hat and put on my design hat and reroute the fuel lines to an accessible and fuel-safe smart spot and refit with appropriate couplers. If you've already rebuilt the new RV several, how 'bout once and for all for the built-in firebug. And here I sit comfortably numb in the monday morning quarterback lounge.
I had a Dodge Caravan that has the fuel pump in the gas tank. The first time I replaced the pump I dropped the tank. The second time I rolled up the carpet, cut an access hole in the floor. When I was done an aluminum plate was used to cover the hole.
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