replacing the first fuel filter on a cat7

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KandT

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Ok DIYers.  I have been told air in the fuel line is a no no for diesels.  Here is my plan. 

Park the 2005 Vectra pointed downhill.  Shut engine off and do all the safety stuff (put that in there so all the safety police know that the wheels will be chalked etc.)

Unscrew the rearmost Fuel Filter (about 7000 miles on the filter but the rig has averaged about 1000 miles a year for 12 years. MY first filter replacement).  The Freightliner dealer only had a 14 micron filter in stock the day I went (don't get me started I did what I needed to do yada yada yada) so I am hoping the inner filter is still good.

With the rig pointed down hill and the engine off, I am going to remove the old filter.  I will fill the new filter with diesel before I screw it back on.  I start the RIG back up and leave it at a fast idle in case a tiny amount of air made its way into the system.

Do I have it?????

Oh and then I dump the old filter on my neighbors grass right?  Just joking!! ;) ;)
 

Journey

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  I take it is the water separator. I cleaned the top of the old filter and water drain before removal. There is a slight vacuum there that may suck in dirt. I also changed the secondary filter using that Cat filter after priming in the small holes on top of filter. Done this twice with no problems parked level.
 

jubileee

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If you screw a 3/4? pipe nipple (I use 3 or 4? long) in the center hole of filter then fill the small holes to about 1/2? from top, you?ll get filtered fuel to your injectors. If you just fill the filter, you?ll get some unfiltered fuel to your injectors. Not good. Injectors are very expensive. I always liked to change filters with a full tank of fuel to help pump pick up. You?re always going to get a little air in system, but it?ll work out.
 

judway

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I have a gallon of clean kerosene from Home Depot or Ace which I use to fill the filter before installation. I have been using this for the last 18 years.
 

Gary RV_Wizard

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[This is a question, not a challenge]  Doesn't an '05 Freightliner chassis (that's what's under the Horizon) have an electric lift pump (moves fuel from the tank to the primary filter)?  I know the ones with Cummins engines do.  The electric lift pump will do a decent job of priming the primary filter, simplifying the job.  To prime with an electric lift pump, turn the ignition key on without cranking the engine. Turn it off after 30 seconds.  Repeat this cycle several times an the primary pump should fill nicely. The old Cats used to come with a mechanical primer pump, but I think they dropped that when electric lift pumps came into use.

Nothing wrong with pre-filling the filter, though, as long as you use one of the methods of insuring there is no unfiltered fuel in it.

Second question: What does parking with the nose downhill achieve?  The fuel line isn't gravity feed, the distance in a rear engine diesel is only a few feet, and the line has whatever hills and valleys are needed to work around other components. I don't see the point.
 

8Muddypaws

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If you're really worried about it Cat makes a manual pump you can add near your secondary filter.  Install the filter dry and pump it until all the air is out of the system.  It's not expensive but there are different pumps for different SN ranges.  They look like this : https://www.amazon.com/Primer-Caterpillar-Engines-183-2823-1832823/dp/B07DWM67H5/ref=sr_1_fkmr1_2?ie=UTF8&qid=1532530033&sr=8-2-fkmr1&keywords=Cat+manual+fuel+primer but yours may be different.

I use pre filtered diesel and pump it into the filters by hand before spinning the filter on.  Messy job.
 

cbeierl

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Gary RV_Wizard said:
[This is a question, not a challenge]  Doesn't an '05 Freightliner chassis (that's what's under the Horizon) have an electric lift pump (moves fuel from the tank to the primary filter)?  I know the ones with Cummins engines do.  The electric lift pump will do a decent job of priming the primary filter, simplifying the job.  To prime with an electric lift pump, turn the ignition key on without cranking the engine. Turn it off after 30 seconds.  Repeat this cycle several times an the primary pump should fill nicely. The old Cats used to come with a mechanical primer pump, but I think they dropped that when electric lift pumps came into use.
...
The CAT C7 doesn't have an electric lift pump (at least on our 2004/2005 vintage ones).

Gary RV_Wizard said:
Second question: What does parking with the nose downhill achieve?  The fuel line isn't gravity feed, the distance in a rear engine diesel is only a few feet, and the line has whatever hills and valleys are needed to work around other components. I don't see the point.
I believe the idea is to get the filter/separator above the height of the fuel tank to try to avoid losing a lot of fuel out of the line when changing the filter.  I've never worried about this myself and haven't had any problems changing mine.

Here's an old thread of mine over on iRV2.com that might be helpful:  Relocated Fuel Filter & Added Priming Pump
 

KandT

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cbeierl said:
The CAT C7 doesn't have an electric lift pump (at least on our 2004/2005 vintage ones).
I believe the idea is to get the filter/separator above the height of the fuel tank to try to avoid losing a lot of fuel out of the line when changing the filter.  I've never worried about this myself and haven't had any problems changing mine.

Here's an old thread of mine over on iRV2.com that might be helpful:  Relocated Fuel Filter & Added Priming Pump

Yes, thank you for your explanation and that was my thought process. IF the lines were pointed downhill they would be less likely to bleed out diesel and hence less/no air enters the system.

I tend to make things more difficult than they need to be and this is my first time doing this.  I appreciate everyone's comments and they have helped my confidence that this should be a straightforward process.

Love the forum!!!
 

KandT

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cbeierl said:
The CAT C7 doesn't have an electric lift pump (at least on our 2004/2005 vintage ones).
I believe the idea is to get the filter/separator above the height of the fuel tank to try to avoid losing a lot of fuel out of the line when changing the filter.  I've never worried about this myself and haven't had any problems changing mine.

Here's an old thread of mine over on iRV2.com that might be helpful:  Relocated Fuel Filter & Added Priming Pump

Chris I ordered a fleet guard fs1242B for the primary filter/water separator.  And a Cat 1R-0751 for the final filter. 

Oddly, it seemed like the pics showed different FS1242 filters??  I ordered one with a basin.

Is that what you use?

The Freightliner mechanic told me that "as long as it fits it will work". Now I am not educated too much but it seems like it need to fit and be the correct micron size.  Giving him the benefit of the doubt I guess maybe he was suggesting I don't need a particular brand but it needs to fit up properly.
 

cbeierl

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KandT said:
Chris I ordered a fleet guard fs1242B for the primary filter/water separator.  And a Cat 1R-0751 for the final filter. 

Oddly, it seemed like the pics showed different FS1242 filters??  I ordered one with a basin.

Is that what you use?

The Freightliner mechanic told me that "as long as it fits it will work". Now I am not educated too much but it seems like it need to fit and be the correct micron size.  Giving him the benefit of the doubt I guess maybe he was suggesting I don't need a particular brand but it needs to fit up properly.
I've always gone with the Freightliner 'Alliance' filter for the primary/water separator and the CAT 1R-0751 for the secondary.  The price at my local Freightliner service folks has always been pretty reasonable.  According to AccessFreightliner my chassis shipped with the 30u primary/water separator, but I've been running the 10u one for years since that what the Freightliner folks have given me.  As far as I know either 10u or 30u is OK as long as you have the CAT 2u secondary at the engine.  Freightliner also provided the clear bowl for the separator--I have a spare so I can pre-attach it to the new filter and then just swap the while assembly when changing the filter.

    1R0751 is the 2u CAT secondary filter.

    ABP-N122-S3226FL01 (aka ABPN122R50419 or ABPS3226FL01) is a 10u Alliance primary/water separator.

    ABP-N122-S3226FL02 (aka ABPN10GFS19593 or ABPS3226FL02) is a 30u Alliance primary/water separator.
 

KandT

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cbeierl said:
I've always gone with the Freightliner 'Alliance' filter for the primary/water separator and the CAT 1R-0751 for the secondary.  The price at my local Freightliner service folks has always been pretty reasonable.  According to AccessFreightliner my chassis shipped with the 30u primary/water separator, but I've been running the 10u one for years since that what the Freightliner folks have given me.  As far as I know either 10u or 30u is OK as long as you have the CAT 2u secondary at the engine.  Freightliner also provided the clear bowl for the separator--I have a spare so I can pre-attach it to the new filter and then just swap the while assembly when changing the filter.

    1R0751 is the 2u CAT secondary filter.

    ABP-N122-S3226FL01 (aka ABPN122R50419 or ABPS3226FL01) is a 10u Alliance primary/water separator.

    ABP-N122-S3226FL02 (aka ABPN10GFS19593 or ABPS3226FL02) is a 30u Alliance primary/water separator.

Thanks Chris!!  Again, once I do this once it will be no big deal but I have a nasty habit of making things harder than they need be.

So primary filter I ordered is 20u so I should be in good shape even though it is not the exact same as yours??  As long as everything lines up??  Meaning that the diameters line up and the threads are appropriate?

As stated, I ordered the same secondary filter at the engine so should be in good shape there.  We put about 7000 miles on the ole beauty in less than a year so I hope any crap in the tank has worked it?s way out.  I figure that is about 1000 gallons through the 100 gallon tank. 

I have a hill by my house that is steep and usually I slow to 38 mph.  Lately I have been slowing to 32 mph so hopefully this helps in the power department. 

I so appreciate this forum and the memeber?s advicevery much.  Thanks all!
 

cbeierl

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cbeierl said:
...According to AccessFreightliner ...
Actually, these days it's known as DTNAConnect (Daimler Trucks North America).  If you're not familiar with that it gives you direct access to the Freightliner info about your coach.  As a Freightliner owner you're entitled to get a login account there to access info about your coach.
 

KandT

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Thanks all - Boy was that ever easy. 

Reading the forum and the advice had me knowing how to do it, and what to expect. 

Coach started right up afterward and I left it at a quick idle for a bit and it seems good to go.

Is it just me or does everything seem to run and sound better after some maintenance is performed????

Thanks again - Had it done in no time.
 
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