2003 U295 Generator Coolant Valves and Lines from Tank

Topic: 2003 U295 Generator Coolant Valves and Lines from Tank (Read 1263 times) previous topic - next topic

2003 U295 Generator Coolant Valves and Lines from Tank

May 01, 2019, 01:15:03 pm

HI folks.

Yesterday I was just doing a walk around and saw these lines with cracks in them. I am confused as why the valves are shut. I want to replace the lines, but need to understand what they do, and why are the valves closed?, anything I need to do, procedures etc.

I'm at this location for 3 days, so hopefully I can get an answer back, thanks in advance.

Thanks, Paul

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #1 – May 01, 2019, 02:20:31 pm

Those are the PowerTech coolant system air bleed ports to the surge tank. There is an excellent explanation on how to properly bleed the generator cooling system of any trapped air — in Barry Brideau's Beam Alarm document set, (Quoted here for your convenience):

The proper procedure for bleeding the coolant system on 2002 (+) Powertech Generators:

1) Close the two aeration valves (handles will be vertical when closed) located on the surge tank in the D-1 compartment.

2) Remove the two lines from the valves and place the ends in the coolant recovery jug, if the level is 1/2 or less, or just use a suitable catch jug.
3) Fill the system with extended life premixed coolant until the surge tank is full and level is stable.
4) Remove the coolant recovery jug line from the fitting beneath the cap.
5) Install the radiator cap.
6) Use a rubber tipped air blower ( with bleed ports), to pressurize the surge tank through the fitting beneath the radiator cap for the coolant recovery jug.
7) Observe the coolant flowing from the two aeration lines placed in the coolant recovery tank or the catch jug. When the coolant is free of air , stop the air flow to the surge tank, and place fingers on the ends of the line to prevent air from being sucked in.

Reinstall the lines on the valves. Reinstall line to coolant jug.
9) Open the valves (handles horizontal).
10) Refill the surge tank until completely full.
11) Run the generator for about 1 hour minimum, longer if possible.
12) If the generator shuts down with a flashing low oil pressure light , the low coolant level switch has shut down the generator. Top off the tank and restart.
13) After running an hour or more, stop generator and, top off surge tank.
14) Recheck levels in coolant recovery jug.
15) Close valves on surge tank. Refill procedure is finished.
Notes:
A. If a large amount of air is left in the surge tank, coolant will not be sucked from the recovery jug. That is why you run the generator as long as possible with aeration valves open to make sure all the entrapped air returns to the surge tank.
B. System capacity is approximately 4 1/2 gallons for a dry unit.

End Quote:

HTH,
Neal

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #2 – May 01, 2019, 03:47:13 pm

Thanks Neal, what a write up! Sounds like something i need a repair guy for, i'm at a remote campground and thought it was possibly simple
line change. Now i'm worried.

Are these lines filled with air, or fluid? Do you think this is something i can wrap some of that emergency stop leak tape stuff around to get me to a real town! I don't want to have fluids all over the campground or street either...

Thanks, Paul

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #3 – May 01, 2019, 04:57:22 pm

Quote from: OSIN – May 01, 2019, 03:47:13 pm

Thanks Neal, what a write up! Sounds like something i need a repair guy for, i'm at a remote campground and thought it was possibly simple line change. Now i'm worried.
Are these lines filled with air, or fluid? Do you think this is something i can wrap some of that emergency stop leak tape stuff around to get me to a real town! I don't want to have fluids all over the campground or street either...
Thanks, Paul

Paul,
I'm not sure what you are trying to "fix".

It doesn't appear to me that you have a problem. Your photos show a small nick on one of the air removal lines, but the line does not appear to be leaking, either at the nick or as evidenced by surfaces below the lines. Those aeration lines and valves are there to vent high points on the generator to the surge tank, after gross amounts of air have been introduced to the generator during corrective or preventative maintenance, for example after draining, flushing and replacing generator coolant.

Because the radiator is horizontal and is very low in the coolant system, the system must have a surge tank to accommodate system and coolant expansion and contraction during thermal cycles. The surge tank must remain solid (full of coolant) in order for the high point of the surge tank (and of the entire coolant system, which is at the surge tank radiator cap) to be able to push coolant to and draw coolant from the overflow reservoir bottle (inboard of the windshield washer reservoir). As the coolant system heats up, normal (small amounts) of coolant system aeration gases released in the system get swept to and collect at the surge tank high point. These small amounts of gases then get pushed out to the (vented) overflow reservoir along with the small coolant expansion volume and they are therefore purged from the coolant system.

When the generator is shut down again, the coolant system cools down, a vacuum is formed and the overflow tube (which goes to the bottom of the overflow reservoir) draws coolant back into the top of the surge tank, keeping it solid and full of coolant.

So these lines and valves (that are causing you concern) are there only for gross amounts of air removal, since the normal coolant system heating and cooling cycles can only vent small amounts of gas.

Absent evidence of leakage at the nick or valves, leave it alone and have it looked at during your next routine coach service. You asked, so, ideally, the line is filled with generator coolant with perhaps a small amount of air introduced during the last system purge. Your valves are now shut and normal generator operations introduce no flow. The nick only experiences the generator coolant system (low) pressure (whatever the radiator cap is rated for). If the nick develops a leak before your next service, replace the line and use the coolant air removal procedure to restore the generator coolant system to service.

HTH,
Neal

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #4 – May 02, 2019, 05:17:47 pm

Thanks for the excellent explanation. I now understand the generator cooling system better.

I will wrap with some tape for now and replace the hoses when i get some correct coolant and can do the procedure, or just get the wallet out and have another guy do this.

One thing i love about Foretravel is this excellent forum, it always amazes me the knowledge that is within. Thanks again

Paul

Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 10, 2025 ...

2003 U295 Generator Coolant Valves and Lines from Tank

May 01, 2019, 01:15:03 pm

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #1 – May 01, 2019, 02:20:31 pm

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #2 – May 01, 2019, 03:47:13 pm

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #3 – May 01, 2019, 04:57:22 pm

Re: 2003 U295 Generator Coolant Valves and Lines from Tank

Reply #4 – May 02, 2019, 05:17:47 pm

Affiliate Notice