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Topic: Fuel filter assembly identity (Read 2185 times) previous topic - next topic

Re: Fuel filter assembly identity

Reply #25 –
Yes I think that is what causes most of the problems because the orings in the upper and lower metal parts don't get changed because most people don't know they are there.
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: Fuel filter assembly identity

Reply #26 –
If someone knows the dimensions of the O rings, that would help others.

Secondarily, if you know what material they are that would also help.

Let me state it a little more emphatically:  If I had a coach with this primary fuel filter "system", I would absolutely carry two sets of all O rings and as soon as convenient, likely (less emphatically) replace it.

Thanks.
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: Fuel filter assembly identity

Reply #27 –
Brett,  yes this would be very helpful. Part numbers would also make my life less stressful.
Scott

Re: Fuel filter assembly identity

Reply #28 –
Two different sizes for the top and bottom fittings.  One is the 208 Buna but, I don't have the size for the other which is slightly smaller.
Glen & Suzie
1998 U320 36'
Build #5366
2015 Jeep Grand Cherokee Overland
2015 ATC Aluminum 20' Trailer
Previous 1996 U295 40'
Motorcade #17546
Stephenville, TX

Re: Fuel filter assembly identity

Reply #29 –
Spent 32 yrs, Federal Mogul Corp,  Industrial Sales,  among my responsibilities, O-rings (National O-Ring) .
U need 2 things to Identify, given u have no PN.  X section & ID, from the ring itself, a 2— is .139 x section.
 A 208 would have have a .609 I.D..
Thus if the pictured O ring is the same X section it is probably a 207  .546 I'd or 206. .484 i.d    Smaller the #smaller the id.

0—  rings have a X section .070  Starting # 004    .070x,070 I'd
1— rings have a X section  .103
2— rings have a X section  .139
3— rings have a X section  . 210
4— rings have a X section  .275
All design or nominal, tolerances are pretty loose [for a reason] compared to metal parts.

The 1st digit helps with the X section, the last 2 digits are only sequential, nothing to do with the I.D. Except the bigger the # the bigger I.D.

That probably covers it for us older guys, but then there is the conversion to Metrics,  another can of worms so to speak.
Cat-Cummins-Detroit-Allison etc started embracing in the 1990s not so much on O rings, but nuts & bolts etc..

Hope this is not redundant, or more than U want to know.
Bill, Tricia, Sassy  Mostly poodle. Maybe
It,s. 5 o clock somewhere,  ?
MoHo has 3 happy days,  Buy, everything works, sell.
  Hopefully the rest are pleasant days.

Pull 05 Jeep Liberty.

Re: Fuel filter assembly identity

Reply #30 –
Quote from: Seven7 –
Two different sizes for the top and bottom fittings.  One is the 208 Buna but, I don't have the size for the other which is slightly smaller.

This is spot on.  Troubleshooting a no start issue and found diesel/air slowly leaking from the top of the 300200 pre filter housing after a couple of air purges.  The smaller o-ring in the top metal housing was damaged.  Now to figure out the size..... 

And we have an answer.  From a Beaver forum post:

A little follow up....I changed all of my fuel filters today and installed the 300200 new filter screen in the plastic housing. There are a total of 4 Orings involved if you want to renew what was installed to seal the plastic housing ends. The two that come with the new housing are .609 ID by .139CS and are a Part Number 208 (AS568B Aero Space Standard Sizing). These are the larger CS (cross section) O-rings and reside in a recess at the end of the metal castings that face the plastic screen filter housing. About 1/2 inch inside the housing at the top and bottom is a recess in the casting where the .612ID by .103CS Part Number 114 resides.

Racor clear plastic fuel filter (R300200)





2000 U320 4010

Re: Fuel filter assembly identity

Reply #31 –

It is easy to miss the o-rings inside the upper and lower housing unless you know they are there. Even if you purchase a new pre-filter, it does not come with the smaller ones needed for the housing.

These are the ones I ordered.  The ones on the right (114) go inside the housing.  The ones on the left (208) go over the pre-filter.

I ordered from Amazon....but forgot to use the affiliate link  :(

208 Buna-N O-Ring, 90A Durometer, Round, Black, 5/8" ID, 7/8" OD, 1/8" Width (Pack of 50): O Ring Seals: Amazon.com: Industrial & Scientific

114 Buna-N O-Ring, 70A Durometer, Black, 5/8" ID, 13/16" OD, 3/32" Width (Pack of 100): O Ring Seals: Amazon.com: Industrial & Scientific

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
40ft 1997 U320

Re: Fuel filter assembly identity

Reply #33 –
Changing the 114 sized o-ring in the top housing that goes onto the top end of the 300200 plastic pre-filter housing solved my no-start issue. 
2000 U320 4010

Re: Fuel filter assembly identity

Reply #34 –
Quote from: evantwheeler –
Changing the 114 sized o-ring in the top housing that goes onto the top end of the 300200 plastic pre-filter housing solved my no-start issue. 
There is a 114 in the top housing and the bottom housing.  If you only changed the top, you might want to put the bottom one on your to do list.  Top one is easy  since the housing can be removed.

Bottom one required me to squeeze into the compartment so I could see and reach it.....might be a better way, but it was not obvious to me.
40ft 1997 U320

Re: Fuel filter assembly identity

Reply #35 –
Quote from: DayDreamer –
There is a 114 in the top housing and the bottom housing.  If you only changed the top, you might want to put the bottom one on your to do list.  Top one is easy  since the housing can be removed.

Bottom one required me to squeeze into the compartment so I could see and reach it.....might be a better way, but it was not obvious to me.

Thanks.  I did actually changed all 4, but the top 114 was definitely the culprit as it had someone torn during past service, but the failure delayed a year before causing the no-start issue. 
2000 U320 4010

Re: Fuel filter assembly identity

Reply #36 –

Curious why you ordered the 114 in 70A and the 208 in 90A.  Why not both 70A or 90A?

Quote from: DayDreamer –
It is easy to miss the o-rings inside the upper and lower housing unless you know they are there. Even if you purchase a new pre-filter, it does not come with the smaller ones needed for the housing.

These are the ones I ordered.  The ones on the right (114) go inside the housing.  The ones on the left (208) go over the pre-filter.

I ordered from Amazon....but forgot to use the affiliate link  :(

208 Buna-N O-Ring, 90A Durometer, Round, Black, 5/8" ID, 7/8" OD, 1/8" Width (Pack of 50): O Ring Seals: Amazon.com: Industrial & Scientific

114 Buna-N O-Ring, 70A Durometer, Black, 5/8" ID, 13/16" OD, 3/32" Width (Pack of 100): O Ring Seals: Amazon.com: Industrial & Scientific


As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Dan & Lauren - Pine Ridge, FL
2000 U320 42 CAI
Build #5766

Re: Fuel filter assembly identity

Reply #37 –
Quote from: Blueeyedme –
Curious why you ordered the 114 in 70A and the 208 in 90A.  Why not both 70A or 90A?

No reason other than those were the ones readily available.
Outside my area of expertise, but guessing the softer 70A is preferred for this application.

40ft 1997 U320
 

Re: Fuel filter assembly identity

Reply #38 –
I had the same problem last month when I overnighted in Why, AZ on the way to Puerto Penasco.  No start in the morning.  Got on the phone with Red Tractor my goto for all things Foretravel and saw there was no fuel in the pre-filter.  Purged it and tried again - still won't start and no fuel in the pre-filter again.  I say 'Hey Ron, is this thing supposed to spin like a top'....problem found.  Disassembled and their were NO inside o-rings at all!  It was a Sunday morning and fortunately the hardware store in Ajo was open.  Didn't have anything that fit in inners so I doubled up the outside o-rings which sealed it up and allowed me to continue my trip and get all the way back home.  Thanks for the info here and I have now ordered the proper sizes. 
Dan & Lauren - Pine Ridge, FL
2000 U320 42 CAI
Build #5766