templeandgary Report post Posted March 19, 2020 I am looking for advice regarding the water fuel separator on my 2018 Entegra Coach. I have a 450hp Cummins ISL9 with the type of Separator that you twist the knob on the bottom to drain the water from. According to everything I have read you should do this periodically. I took my coach in for its first annual service to a very reputable repair facility. The Service Adviser told me I should never do this. He said that i should trust the sensor, it will let me know if there is water in the system. He said that if I drain the separator there is the potential for getting air in the system and then the coach wont start. He said that if I insist that I should drain no more than a shot glass of fluid and then start the engine and let it run before draining more in order to avoid a air pocket in the fuel system. Again he reinforced that I should not have to drain this. Any opinions? Share this post Link to post Share on other sites
kaypsmith Report post Posted March 19, 2020 14 minutes ago, templeandgary said: He said that if I drain the separator there is the potential for getting air in the system and then the coach wont start. He correct, you should never completely drain the separator, there is no need to completely drain it. But you should follow the manual that came with the coach. Most systems have a manual pump to prime the fuel system and it should be used in conjunction with dumping some fuel from the system if possible. The water will drop to the bottom of the separator, let the water out only then refill the separator. Share this post Link to post Share on other sites
wolfe10 Report post Posted March 19, 2020 First, a question: do you have only that one or do you have two fuel filters? This is critical to make sure you get the correct micron rating filter(s). Let us know and post what fuel filter number(s) you have. Most primary fuel filters have either a clear bowl so you can see if there is water or dirt in the fuel (my reference) or a drain. As already stated, if all you have is a drain, you only need to drain an ounce or so-- if all you get is clean diesel, close it. Water and dirt settle to the bottom of the filter, so if either are present, they will come out immediately. Again, all you are doing is opening the drain until clean, clear diesel comes out. Share this post Link to post Share on other sites
hermanmullins Report post Posted March 19, 2020 I have two filters on my 400 ISL. When I check mine I will drain, into a clear container, just enough so I can see if there is any seperation of the fuel aka water or trash. I have been very fortunate that I have never found either. Herman Share this post Link to post Share on other sites
rayin Report post Posted March 19, 2020 5 hours ago, hermanmullins said: I have two filters on my 400 ISL. When I check mine I will drain, into a clear container, just enough so I can see if there is any seperation of the fuel aka water or trash. I have been very fortunate that I have never found either. Herman nailed it! Share this post Link to post Share on other sites
templeandgary Report post Posted March 19, 2020 Thanks for everybody replies, I appreciate it. To answer a question above I have two filters. A Primary Fleetguard FS-1003 and a Secondary FF-5636. I don't have a clear bowl on either of the filters. Just a twist type Drain Knob on the bottom of the separator. I have spoken with a few different people in the RV club that I camp with occasionally and they all recommend carrying spare fuel filters with me however, I am reluctant to change these myself. As a former light duty auto mechanic I know the importance of following manufacturer guidelines for procedures and when I look up the procedures for changing the fuel filters on my motor the recommend priming the filter every time you change it which requires gauges and other fittings along with specific procedures. The guys that I camp with just twist off the old ones and spin on new ones? Seems risky to me but this is coming from a very conservative former mechanic that looked up torque specs for just about every nut and bolt that I tightened. Maybe I am thinking way too hard here but to me it makes sense to just get it serviced annually by a professional who deals with Heavy Diesel for a living. I just want to make sure I am doing my due diligence as a responsible owner and if checking the drain periodically is really necessary or just rely on the warning light is the best way to prevent accidental issues. I really don't want to have to explain to my wife that the reason that we are now stuck at a campground is because I thought it would be a good idea to see if there was any water in my fuel filter😐 Share this post Link to post Share on other sites
wolfe10 Report post Posted March 19, 2020 Carry at least one spare of each fuel filter. You WILL be able to find someone who knows how to replace them. But, you may be in an area where finding the correct filter is not so easy. Also, check your Cummins manual or contact Cummins so you know the correct filter change/prime procedure. I know on our 2003 ISL, the electric fuel pump would prime the filters merely by turning the key to the first position a couple of times. VERY EASY. Share this post Link to post Share on other sites
templeandgary Report post Posted March 19, 2020 24 minutes ago, wolfe10 said: Carry at least one spare of each fuel filter. You WILL be able to find someone who knows how to replace them. But, you may be in an area where finding the correct filter is not so easy. Also, check your Cummins manual or contact Cummins so you know the correct filter change/prime procedure. I know on our 2003 ISL, the electric fuel pump would prime the filters merely by turning the key to the first position a couple of times. VERY EASY. That makes a lot of sense. Thank you! Share this post Link to post Share on other sites
campcop Report post Posted March 19, 2020 We have the same engine in our Tiffin and I change my filters each year myself. If yours are mounted at the rear of the engine instead of under it, the procedure is easy and no messy fuel spills. I fill the new filters with clean fuel as directed on the filter itself. Engine always starts right up. And as mentioned carry both filters for spares. We had a fuel filter fail near Big Bend NP once on our previous Phaeton. It was not fun, those filters are on the bottom of the engine and with a full tank of fuel, it was mess as the fuel line will run. And with a hard plastic type fuel line, you can’t pinch it off. That time I used the prime method with turning the key on for a few seconds and then off, repeated several times. And also carry a 25mm socket for the black filter. Share this post Link to post Share on other sites
huffypuff Report post Posted March 19, 2020 14 hours ago, templeandgary said: I am looking for advice regarding the water fuel separator on my 2018 Entegra Coach. I have a 450hp Cummins ISL9 with the type of Separator that you twist the knob on the bottom to drain the water from. According to everything I have read you should do this periodically. I took my coach in for its first annual service to a very reputable repair facility. The Service Adviser told me I should never do this. He said that i should trust the sensor, it will let me know if there is water in the system. He said that if I drain the separator there is the potential for getting air in the system and then the coach wont start. He said that if I insist that I should drain no more than a shot glass of fluid and then start the engine and let it run before draining more in order to avoid a air pocket in the fuel system. Again he reinforced that I should not have to drain this. Any opinions? Follow your service guy advice and let them change both filters at you annual service. I do this and stopped carrying filters. I also do this for generator filter. Share this post Link to post Share on other sites
wolfe10 Report post Posted March 19, 2020 1 hour ago, huffypuff said: Follow your service guy advice and let them change both filters at you annual service. I do this and stopped carrying filters. I also do this for generator filter. I sure have to disagree here. Not being prepared for that (yes, rare) tank of contaminated fuel is an unnecessary risk. Again, carry them whether you can install them or have them on hand for someone else to install. Only downside is having filters on hand ahead of when you know you will need them. Share this post Link to post Share on other sites
huffypuff Report post Posted March 19, 2020 1 hour ago, wolfe10 said: I sure have to disagree here. Not being prepared for that (yes, rare) tank of contaminated fuel is an unnecessary risk. Again, carry them whether you can install them or have them on hand for someone else to install. Only downside is having filters on hand ahead of when you know you will need them. On my previous coach keeping them clean and dry is and issue. It's hard to get repair shops to rotate stock to your basement. I have the part numbers handy if needed. Using truck stops that's always busy helps to have clean fuel. Share this post Link to post Share on other sites
wolfe10 Report post Posted March 19, 2020 I just put filters in gallon or 2.5 gallon zip locks and in a box with tools to change them in the basement. Even if you do zero work yourself, have the next guy show you what tools are needed and buy them. Again, lots of people know how to do this-- not all of them travel with either the correct filters for your coach or the needed tools to change them on your coach. But, surely, this is an individual decision. No group consensus needed. Share this post Link to post Share on other sites
manholt Report post Posted March 20, 2020 I have to agree with you, Brett. Especially after Joe L's experience with bad fuel about 3 years ago. Share this post Link to post Share on other sites
jleamont Report post Posted March 20, 2020 17 hours ago, templeandgary said: That makes a lot of sense. Thank you! Check Amazon for the Fleetguard number. That seems to be the cheapest, especially if you have Amazon Prime. Share this post Link to post Share on other sites
rayin Report post Posted March 21, 2020 On 3/19/2020 at 1:17 PM, campcop said: We have the same engine in our Tiffin and I change my filters each year myself. If yours are mounted at the rear of the engine instead of under it, the procedure is easy and no messy fuel spills. I fill the new filters with clean fuel as directed on the filter itself. Engine always starts right up. And as mentioned carry both filters for spares. We had a fuel filter fail near Big Bend NP once on our previous Phaeton. It was not fun, those filters are on the bottom of the engine and with a full tank of fuel, it was mess as the fuel line will run. And with a hard plastic type fuel line, you can’t pinch it off. That time I used the prime method with turning the key on for a few seconds and then off, repeated several times. And also carry a 25mm socket for the black filter. Cummins discourages pre-filling fuel filters. The advise cycling the ignition key several times, leaving it in the on position for at least 30 seconds each time. Share this post Link to post Share on other sites
wildebill308 Report post Posted March 21, 2020 Well I am back on that learning curve as I don't have any of the filter part numbers for the MA. I will have spare filters shortly after that. Saying to just let the shop change them at annuel reminded me of the guy who stopped to talk to me up in Michigan the last time I was in the UP. I was checking my tire pressure and he stopped and asked why I was doing that. He had his dealer check his tire pressure in the spring when they did the maintenance and he saw no reason to do it after that. Seriously, I would rather carry spares and not need them than, well you know. Bill Share this post Link to post Share on other sites
manholt Report post Posted March 21, 2020 I'm on your curve also! One interesting thing, I have TMS on all tires & a separate valve for airing each tire! That's a first... Share this post Link to post Share on other sites
