2004 HR Scepter diesel tank dimensions, capacity and how should I modify the filler necks for better fill

[isptbart]

BTW - this modification requires me to fully open my basement compartment fuel door verses the small locking fuel door. So park your rig at the pump to accommodate your compartment door swing.  I can also support the fueling nozzle now on my door gas spring rod which keeps it in place. Sometimes I use a small bungee as well so at auto-fuel cutoff it doesn't pop out. Towards the last quarter tank filling, I reduce the fuel speed to cut down on diesel fuel foaming too! I also have the 3 point hydraulic leveling & I find it too much of a problem to lean the RV too much & most importantly the DW inside doesn't like it either. I like to take precautions about unnecessarily leaning or twisting the coach in relation to the many posted windshield issues - so I just don't take too many chances with that!

PS - In case your fuel tank is different than mine, before you cut off your existing fuel tank filler tube I suggest you do a dry assembly of the parts to check your particular needs for a best modification for your coach! Getting ready to leave for our extended winter trip in the Southwest!

Bart from VA, 07 HR 42PLQ Scepter, 07 GMC 2500HD in tow

1 minute ago, isptbart said:

BTW - this modification requires me to fully open my basement compartment fuel door verses the small locking fuel door. So park your rig at the pump to accommodate your compartment door swing.  I can also support the fueling nozzle now on my door gas spring rod which keeps it in place. Sometimes I use a small bungee as well so at auto-fuel cutoff it doesn't pop out. Towards the last quarter tank filling, I reduce the fuel speed to cut down on diesel fuel foaming too! I also have the 3 point hydraulic leveling & I find it too much of a problem to lean the RV too much & most importantly the DW inside doesn't like it either. I like to take precautions about unnecessarily leaning or twisting the coach in relation to the many posted windshield issues - so I just don't take too many chances with that!

PS - In case your fuel tank is different than mine, before you cut off your existing fuel tank filler tube I suggest you do a dry assembly of the parts to check your particular needs for a best modification for your coach! Getting ready to leave for our extended winter trip in the Southwest!

Bart from VA, 07 HR 42PLQ Scepter, 07 GMC 2500HD in tow

Ooops! Forgot to try to rotate my coach Covid ready photo! :>)

[tomgagne55]

Great analysis and solution.  Unfortunately I only have the small access door on my Diplomat so the fuel fill modification can’t be done.  However, I do plan on extending my generator fuel pick up to avoid the shutdown at 1/2 a tank (for me and my current gauge indication). If I extend the pickup 4 inches it should give me an additional 25 gallons (1/4 tank) of access for the generator.   The 1/4 tank will be more than enough to extend the generator usable range for my driving habits.  I did run my fuel down once to force the low fuel light to illuminate and will not do that again after reading all the stories regarding the accuracy of the fuel gauge.    Thanks ok-rver !

Can someone point me to the thread regarding adding an external fuel filter on a generator?   I searched and could not find it.

[isptbart]

1 hour ago, tomgagne55 said:

Great analysis and solution.  Unfortunately I only have the small access door on my Diplomat so the fuel fill modification can’t be done.  However, I do plan on extending my generator fuel pick up to avoid the shutdown at 1/2 a tank (for me and my current gauge indication). If I extend the pickup 4 inches it should give me an additional 25 gallons (1/4 tank) of access for the generator.   The 1/4 tank will be more than enough to extend the generator usable range for my driving habits.  I did run my fuel down once to force the low fuel light to illuminate and will not do that again after reading all the stories regarding the accuracy of the fuel gauge.    Thanks ok-rver !

Can someone point me to the thread regarding adding an external fuel filter on a generator?   I searched and could not find it.

 

1 hour ago, tomgagne55 said:

Great analysis and solution.  Unfortunately I only have the small access door on my Diplomat so the fuel fill modification can’t be done.  However, I do plan on extending my generator fuel pick up to avoid the shutdown at 1/2 a tank (for me and my current gauge indication). If I extend the pickup 4 inches it should give me an additional 25 gallons (1/4 tank) of access for the generator.   The 1/4 tank will be more than enough to extend the generator usable range for my driving habits.  I did run my fuel down once to force the low fuel light to illuminate and will not do that again after reading all the stories regarding the accuracy of the fuel gauge.    Thanks ok-rver !

Can someone point me to the thread regarding adding an external fuel filter on a generator?   I searched and could not find it.

Open your small fuel door to see if by making this modification it could still work by extending the fill nozzle & slightly rotating the modification to the top of your small fuel door for filling? I can still use the small fuel door but easier for me to see everything with the full compartment door open. I have seen this done in situations such as yours. The owner just removed the compartment panel, made the modification just slightly smaller than mine, & reinstalled the compartment panel. 

[W7BE_Bob]

4 hours ago, tomgagne55 said:

Great analysis and solution.  Unfortunately I only have the small access door on my Diplomat so the fuel fill modification can’t be done.  However, I do plan on extending my generator fuel pick up to avoid the shutdown at 1/2 a tank (for me and my current gauge indication). If I extend the pickup 4 inches it should give me an additional 25 gallons (1/4 tank) of access for the generator.   The 1/4 tank will be more than enough to extend the generator usable range for my driving habits.  I did run my fuel down once to force the low fuel light to illuminate and will not do that again after reading all the stories regarding the accuracy of the fuel gauge.    Thanks ok-rver !

Can someone point me to the thread regarding adding an external fuel filter on a generator?   I searched and could not find it.

Do you have the Centroid fuel gauge and considered adjusting it. I'm skeptical that the pickup is at 1/2 tank. Remove the gen hose, insert a small wire with a short  90 degree bend to probe the pickup end and determine just how deep it is. 

Both of my Centroid have been very accurate and repeatable. Monaco's wide shallow cross tank and Centroid on one side however causes the fuel level to change and hence the gauge changes like on a crowned road. The gauge is very highly damped and hence doesn't immediately change. 

I would NOT extend the pickup to 1/4  tank which would be at or close to the engine pickup and that exposes you to air pickup for the engine. There are baffles in the tank but with the cross tank design air intake can happen. If that heppens to a diesel you can go from full throttle to dead with no warning.

Plus if your gen pickup is welded in place it will be a big job to remove the tank.

My gen pickup is at 3/8 and engine at 1/4 maybe a little below. My 130 gal tank is about 100 gal with a level fill. When tilted I can add 15-20 gallons.

To the person who suggested moving the engine pickup lower - DON'T for the reasons above - ie you will be exposed to air pickup. You can probe the engine pickup per above the post and then purge the engine of air before driving. 

Given the tank location Monaco's fuel pickups are set for very good reasons. Of course they could have installed the wrong pickup.

Edited December 10, 2021 by W7BE_Bob

[tomgagne55]

24 minutes ago, W7BE_Bob said:

Do you have the Centroid fuel gauge and considered adjusting it. I'm skeptical that the pickup is at 1/2 tank. Remove the gen hose, insert a small wire with a short  90 degree bend to probe the pickup end and determine just how deep it is. 

Both of my Centroid have been very accurate and repeatable. Monaco's wide shallow cross tank and Centroid on one side however causes the fuel level to change and hence the gauge changes like on a crowned road. The gauge is very highly damped and hence doesn't immediately change. 

I would NOT extend the pickup to 1/4  tank which would be at or close to the engine pickup and that exposes you to air pickup for the engine. There are baffles in the tank but with the cross tank design air intake can happen. If that heppens to a diesel you can go from full throttle to dead with no warning.

Plus if your gen pickup is welded in place it will be a big job to remove the tank.

My gen pickup is at 3/8 and engine at 1/4 maybe a little below. My 130 gal tank is about 100 gal with a level fill. When tilted I can add 15-20 gallons.

To the person who suggested moving the engine pickup lower - DON'T for the reasons in my prior post - ie you will be exposed to air pickup. You can probe the engine pickup per above the post and then purge the engine of air before driving. 

Given the tank location Monaco's fuel pickups are set for very good reasons. Of course they could have installed the wrong pickup.

Yes I do have a centroid gauge.  I typically fill the tank to the B line which shows 95 gallons and the generator cuts out just above 1/2 and generally will take around 40 gallons, so there is still 55 gallons left in the tank.  Again filled back to the B level on the diagram.  The generator is cutting off close to the 1/2 marker.   I purchased a kit to extend the pickup tube for the generator.  I just wasn’t sure how long to extend it, as I didn’t want to hit the bottom of the tank.  I could recalibrate the gauge but I’ve seen some discrepancies with the readings at times.  Mostly I just refill based on mileage or when the generator quits.  I typically run only in the summer and need the generator running for AC.  It’s one of those things I want to do, I just haven’t got around to doing it.  

I don’t understand how lowering the generator pickup will cause air in the engine pickup.  That is of course if the fuel is above the pickup in the tank.  I’m looking to extend my driving range per tank based on the generator from currently refilling at around 320 miles and moving closer to 500 mile fill ups.  The additional 4 inches will give me another 26 gallons of usable fuel for the generator and leave 25+ gallons remaining in the tank.   I stop more often, but I don’t want to refill at every stop either.  Refilling every other day would be nice.  Thanks for the response. 

[W7BE_Bob]

With the shallow cross tank the fuel sloshes side to side and when lower air can be drawn in. By design the gen pickup is above the engine  so that the gen can't draw out enough fuel to cause the engine to quit before there is adequate time to get more fuel. 

If the gauge issue is not related to the coach leaning like on a hill I would fix the problem. Note: When the engine is started the gauge recalibrates and after that it takes a few minutes to change the needle due to the damping. At least both of mine have been accurate and consistent.

Certainly a gen pickup at 1/2 full is restrictive. I track all of my fuel usage and have a 7.8 MPG average for 10 fill ups. However a single tank tank fill varies considerable from 4-12 MPH due to filling and driving conditions. Hence it pays to be careful and aware of when to fill again based on mileage because of the shallow cross tank design. Ditto on assuming a gauge is accurage.

My low light comes on at just under 1/4 and my gen cutoff is about 3/8 full. I've gone 600 mi with but don't go further with mountain driving ahead. 

Generally it's recommended to use 3 or more (or even more for me) fillups to calculated MPG because of the shallow cross tank design.

Centroid calibration basics: It's cut to length for Empty. Revove the gauge and measure it to determine the empty location on the tank if you want. Then while removed set the low adjustment so that the gauge is on E. Install the gauge and on a level fill the tank normally. Drive to a nearby level area and adjust the full setting to F on the gauge. Centroid has more information.

FWIW In 2005 Monaco under warranty twice tried to adjust my gauge and failed to get close. I then read the directions and made the adjustment. 

[StephenW]

To tomgagne55's question about mounting an external fuel filter on the generator, you can find some info and a picture of what ChuckB, 2004 Windsor, did on his coach on this site under Browsing--Electrical...Generators.  The thread is titled Generator Quit Running.  Looks like a great idea to me and I have put it on my future upgrade list,  along with a Fass System.

[georgecederholm]

14 hours ago, StephenW said:

To tomgagne55's question about mounting an external fuel filter on the generator, you can find some info and a picture of what ChuckB, 2004 Windsor, did on his coach on this site under Browsing--Electrical...Generators.  The thread is titled Generator Quit Running.  Looks like a great idea to me and I have put it on my future upgrade list,  along with a Fass System.

I used Chuck’s design concept on our 2005 Exec with some slight modifications (larger generator meant different filter placement). I thought the document I made had migrated to the Files Section, but maybe not.

http://ourrvrepairs.blogspot.com/2015/04/rv-generator-remote-fuel-filter.html

 

[StephenW]

Thank you George C for the info and pics from your blog.  Nice looking job and l like the idea of a shutoff valve ahead of the filter.