Skip to main content
Topic: 1998 Foretravel U295 - Air in fuel system question (Read 7913 times) previous topic - next topic

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #250
The parking spot is flat
The engine died because the canister ran out
Of fuel
I may have left the key in on position in order to make leveling control panel work
only one air bag didn't go high enough , no idea why
I will test both the old and new solenoids tomorrow morning to make sure sure they both work , also will make sure the new ons adjustment matches the old one

I can go tomorrow and run it again with a full canister , hopefully it will run long enough to raise the coach

Does the leveling panel have an on /off button?
Or as soon as engine runs, which key will be in ON position , the leveling panel will work
I learned that when both tanks reach 130 PSI
I can place the block and turn the engine off

Today i received the hoses, i am planing to use push one fittings
But planing to order new push on fittings for one end of hoses , also  needed male/male couplers
 
Because , doing this project in a daily limited time at storage yard, i need to have hoses ready in advance , to be connected to the removed ones
In less time
Then, i can remove enough of the existing  fittings
To attach to the other end of hoses


BUT, honestly i am still thinking if i can prime the long hose coming from the tank ( over 30 feet ) the engine will stay running

Then when i drove it to my shop , replacing hoses will be much easier


Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #251
What kind of damage can pressurizing tank can cause
I will loosen the fitting connected to water separator, then using a bicycle pump will pump air in the tank slowly, until i see fuel coming out of the separator fitting

If i didn't see fuel coming, that means the air is escaping through the vent, then i can block the vent hose, and try again
I still like to know why some of you guys believe this is dangerous , why is it?
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #252
Are these clamped hoses my generator fuel lins?
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #253
Are these clamped hoses my generator fuel lins?

Yes.
Top hose is return to tank
Bottom hose is suction/fuel to generator

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #254
What kind of damage can pressurizing tank can cause
I will loosen the fitting connected to water separator, then using a bicycle pump will pump air in the tank slowly, until i see fuel coming out of the separator fitting

If i didn't see fuel coming, that means the air is escaping through the vent, then i can block the vent hose, and try again
I still like to know why some of you guys believe this is dangerous , why is it?

Lets say the top of your fuel tank is 6' x 2' in size.
12 sq.ft. = 12 x 144 sq in per sq. ft. =1728 square inches
Say someone pumps this up to 5 psi with air.
5psi X 1728 sq inches =8640 lbs of force being exerted against the top.  The tank is not made to handle that amount of force.  In addition, that same 5 psi is being exerted against all other surfaces of the tank.

So, no matter how you pressurize the tank it needs to be a small amount, maybe 1 psi.  Better to get a small suction pump (like a throwaway plastic fuel transfer pump) and suck the fuel from end of disconnected hose.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #255
Are they connected by hose clamp?
I have been talking about fittings all time
Please clarify


Yes.
Top hose is return to tank
Bottom hose is suction/fuel to generator

Mike
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #256
Thank you chuck for scientific explanation
Good idea to use a suction hand pump
Hope i can figure out a way to connect the hose fitting ( removed from the separator) to be able to quickly re- attach it to separator without allowing fuel to run back in the tank


Lets say the top of your fuel tank is 6' x 2' in size.
12 sq.ft. = 12 x 144 sq in per sq. ft. =1728 square inches
Say someone pumps this up to 5 psi with air.
5psi X 1728 sq inches =8640 lbs of force being exerted against the top.  The tank is not made to handle that amount of force.  In addition, that same 5 psi is being exerted against all other surfaces of the tank.

So, no matter how you pressurize the tank it needs to be a small amount, maybe 1 psi.  Better to get a small suction pump (like a throwaway plastic fuel transfer pump) and suck the fuel from end of disconnected hose.
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #257
Hope i can figure out a way to connect the hose fitting ( removed from the separator) to be able to quickly re- attach it to separator without allowing fuel to run back in the tank
Simply install a full opening, quarter turn, stainless steel ball valve in the fuel line that runs from the tank to the first filter.  That way, you can close the valve, and then leisurely work on or change either the primary or secondary filters without worrying about fuel siphoning back to the tank.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #258
Simply install a full opening, quarter turn, stainless steel ball valve in the fuel line that runs from the tank to the first filter.  That way, you can close the valve, and then leisurely work on or change either the primary or secondary filters without worrying about fuel siphoning back to the tank.

Agree, a diesel compatible ball valve on the INLET side of the primary fuel filter.  Makes changing filters a leisurely job and also makes a heck of an anti-theft device.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #259
Are they connected by hose clamp?
I have been talking about fittings all time
Please clarify

Those hoses are held on by those gear clamps. Just take the hose clamp loose and the hoses will slip off the fitting as these 2 are different than all the others on a hose change out.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #260
The parking spot is flat
The engine died because the canister ran out
Of fuel
I may have left the key in on position in order to make leveling control panel work
only one air bag didn't go high enough , no idea why
I will test both the old and new solenoids tomorrow morning to make sure sure they both work , also will make sure the new ons adjustment matches the old one

I can go tomorrow and run it again with a full canister , hopefully it will run long enough to raise the coach

Does the leveling panel have an on /off button?
Or as soon as engine runs, which key will be in ON position , the leveling panel will work
I learned that when both tanks reach 130 PSI
I can place the block and turn the engine off

Today i received the hoses, i am planing to use push one fittings
But planing to order new push on fittings for one end of hoses , also  needed male/male couplers
 
Because , doing this project in a daily limited time at storage yard, i need to have hoses ready in advance , to be connected to the removed ones
In less time
Then, i can remove enough of the existing  fittings
To attach to the other end of hoses


BUT, honestly i am still thinking if i can prime the long hose coming from the tank ( over 30 feet ) the engine will stay running

Then when i drove it to my shop , replacing hoses will be much easier

You need to hold the raise button on the HWH until it is fully raised and turn the key off BEFORE releasing the raise button.
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #261
Does this mean turn the engine off before releasing raise button?
If yes, i had the solenoid removed and the pump valve was zip tied in open position  already
Turning the key off wouldn't shut the engine
Engine was running until the canister ran out of fuel and engine died
What happens  if the ignition key stays in on position after engine is shut
Will it still affect raising?
Remember, only one out of 8 bags did not raised
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #262
My understanding during last month was that fuel lines have push on flare fitting
Please see my generator picture and let me know why the lines have hose clamps?
By the way generator always starts
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #263
One more question
If i am ordering the push on flare fittings
What i should order to have the correct thread to mount where the old hoses were mounted
I still like to know what i need to do with generator hose clamps connectors, do i install my new hoses with them connectors? Or what do need to convert to 3/8" push on fittings
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #264
Please see my generator picture and let me know why the lines have hose clamps?

Like the post above those fittings are just a push on and you will find that the barbed end is somewhat loose in that hose so the hose clamps are needed to keep them tight. These most likely these were the only fittings that they had on the shelf during production. These ends are different than the ones on the other end that is attached to the tank. The ones on the tank end are the flair/push on like the rest of the hoses have.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #265
Does this mean turn the engine off before releasing raise button?
If yes, i had the solenoid removed and the pump valve was zip tied in open position  already
Turning the key off wouldn't shut the engine
Engine was running until the canister ran out of fuel and engine died
What happens  if the ignition key stays in on position after engine is shut
Will it still affect raising?
Remember, only one out of 8 bags did not raised

If the key is on, the HWH system will release the air to drop the coach to ride (travel) height.  On mine it drops quickly. 
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #266
I would think that if the key is turned off and even though the engine continues to run because the fuel is tied open, the HWH would not be releasing any air because no power to the travel solenoids.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #267
So , do new foretravel RVs have same hose clamps connectors used on the generator?
Edmond
1998 Foretravel U295
Turlock Ca

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #268
I would think that if the key is turned off and even though the engine continues to run because the fuel is tied open, the HWH would not be releasing any air because no power to the travel solenoids.

 Probably a bad idea to run engine with the Ignition off it may damage Internals of alternator.
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #269
Probably a bad idea to run engine with the Ignition off it may damage Internals of alternator.

How?
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #270

With no load from the vehicle's electrical system the alternator can generate extremely high voltages which can quickly damage sensitive electronic components.
The open circuit condition is very stressful for the alternator's diodes and voltage regulator, potentially causing them to fail or be destroyed.
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #271
With no load from the vehicle's electrical system the alternator can generate extremely high voltages which can quickly damage sensitive electronic components.
I wonder if the DUVAC alternators, commonly fitted to our coaches, would be protected from this potential damage?

With ignition key turned to OFF, the "excite" input would be removed from the alternator.  It would still have the "sense" input.

If the alternator is actively generating voltage when the ignition key is turned off, will it continue to generate voltage without the "excite" input?

Must the "excite" input be seen continuously by the alternator during operation, OR is it only required for initial activation, and then superfluous?

If the alternator would cease all electrical operation (I.E. generating voltage) when the "excite" input is turned off, then it might avoid being damaged.

What say the Forum electrical gurus?

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #272
Yes, the sense wire is connected to battery voltage.  No reason for the alternator to do anything goofy.  You nailed it Chuck.  Does that make you a guru?
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #273
  No reason for the alternator to do anything goofy.

....it cost me a alternator rebuild some years ago on my sailboat, someone forgetting to pull manual shut off on diesel engine before ignition switch, it was a pretty simple system.  Duvac or no Duvac why take the chance....
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: 1998 Foretravel U295 - Air in fuel system question

Reply #274
Sounds like the subject of setting safety blocks ended up learning how alternator will act if the engine is running with key in on position
I like to add another possibility, lets say we try to turn the engine off, but the solenoid spring is broken and after the key is turned off the engine still will stay running until removing the solenoid

But lets go to original issue
I ran the engine using a 5 ballon canister while solenoid was removed and pump valve was zip tied in open position
After i felt the coach is raised, i didn't turn the key to off position knowing that will not shut off the engine
And quickly walk out and started placing the safety blocks
At this point the canister ran out of fuel and engine died, the key still in on position
( didn't know i have to turn it off to keep the coach in raised position , did i have to do that?)
Continued placing blocks
The last one did not fit by the driver side front of the wheel air bags, almost needed two more inches to place the block
Please respond to this , what caused it?
Running out of diesel? But the gauges showed 130 on one and 110 on second tank
There was a 9 3/4 wood block which i placed there the opening was 10" and my blocks are 11 3/4
Please help fixing this now
Placing the blocks was to fix the air in the system and preparing to replace the hoses
Now , another thing to figure out

I am sorry to mix subjects together
I also asked " if all the hoses have push on connectors ?
If so why there are hose clamps on generator lines
Did Foretravel use hose clamps on some hoses?
If i attempt to replace my hoses, I like to do it professional, no hose clamps
Please advise on either subject
Thank you all members




Edmond
1998 Foretravel U295
Turlock Ca