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Topic: Plastic overflo tank cap (Read 1305 times) previous topic - next topic

Plastic overflo tank cap

Lost the plastic screw on cap to the coolant overflo tank,any replacement ideas?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Plastic overflo tank cap

Reply #1
Yikes! It's probably a generic part but finding it could be a PIA. I'd call FOT parts.

see ya
ken
The selected media item is not currently available.ken & dori hathaway & Big Agnes
🍺1992 U300 GrandVilla WTBI #4150 FOT FBP 2011
✨6V-92TA DDEC Parlor Coach 350HP Series 92
🏁2011 Nissan XTerra Pro-4X

Re: Plastic overflo tank cap

Reply #2
Yup, call Foretravel parts.

And, in the meantime, put aluminum foil or similar over it so you do not get dirt in the cooling system.  Remember, any dirt that gets in the overflow reservoir settles to the bottom of the reservoir.  Next time the engine cools, it sucks whatever is in the bottom of the reservoir back into the engine/cooling system.
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: Plastic overflo tank cap

Reply #3
Remember, any dirt that gets in the overflow reservoir settles to the bottom of the reservoir.  Next time the engine cools, it sucks whatever is in the bottom of the reservoir back into the engine/cooling system.
Where it is trapped by the coolant filter?
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: Plastic overflo tank cap

Reply #4
Where it is trapped by the coolant filter?

Maybe.  But the coolant filter is a LONG way from where the overflow reservoir enters the cooling system.  Lots of places for dirt to hide.
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: Plastic overflo tank cap

Reply #5
Wish I had remembered to ask at FOT last week.  Mine is cracked, but nicely taped. 
Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)

Re: Plastic overflo tank cap

Reply #6
Wish I had remembered to ask at FOT last week.  Mine is cracked, but nicely taped. 

Tape is OK.  It is not pressurized.  The overflow reservoir cap's job is just to keep dirt out of the system.
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: Plastic overflo tank cap

Reply #7
Tape is OK.  It is not pressurized.  The overflow reservoir cap's job is just to keep dirt out of the system.

Thanks, as I had noticed that tiny hole in the cap, and then tried to source it in NM, all summer, each and every time I found a parts store with someone willing to search the data files.

Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)

Re: Plastic overflo tank cap

Reply #8
EVERY removable cap in  our coach has a string fastened to it to prevent loss in case it is removed, set down and not put back on.  And that is a lot of caps considering hydraulic, cooling, fuel, lub, etc, not to mention a lot of string. . .

Re: Plastic overflo tank cap

Reply #9
I had mine break and FOT only sells the entire bottle with cap.  That was two years ago now.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon


Re: Plastic overflo tank cap

Reply #11
Found 2 cheap solutions for cap,found a sears craftsman riding mower gas cap that fits and also a spray paint plastic top will
work with a hose clamp.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Plastic overflo tank cap

Reply #12
John44 do you know what the Sears cap was for or the part number?
2002 U320 40Ft  MC # 15759
Coach # 5995
Previous coaches
2002 U320 coach  #5941
1996 U270 coach #4808

Re: Plastic overflo tank cap

Reply #13
Sears part number 751-0603A.just tried it works perfect.
96 U270 BUILD 4810
85 380SL
Drummonds TN.


Re: Plastic overflo tank cap

Reply #15
You might try NAPA. I don't know if mine would be the same as yours, but I found an exact replacement at a NAPA store. Mine was cracked, I took it in, they matched it.
Royce & Denise, MC #17410
'01 U320 4220 ISM450 Build #5895 SOLD
Toad: '10 Honda CR-V

Travel makes one modest. You see what a tiny place you occupy in the world. - Gustave Flaubert

Re: Plastic overflo tank cap

Reply #16
I found one that fit perfectly off an old sprayer.  So they are nothing exotic.
1996 U270
Build #4846

Re: Plastic overflo tank cap

Reply #17
Update on cap,Foretravel now has them for $5.50 before discount.
96 U270 BUILD 4810
85 380SL
Drummonds TN.