Changing Fuel Filters

[Dick Simonis]

Next week I'm going to change both fuel filters as well as upgrade the existing Raycor with the upgrade kit, new strainer and new o-rings.

I read several comments that the Cat secondary filter should be installed "dry" but I'm unclear as to eliminating the air.  Do I just start the engine and the air takes care of itself??

The Racor should be simple, just put it back together and hit the air bleed button and, presumably when I see fuel coming out it's done.  I figure that this should be done first and than run the engine for a bit while checking for any air/fuel leaks than do the secondary.

I have all the parts for the Racor and the Cat filter will be here tomorrow so I'll probably do the job mid week.  Still have almost a 3/4 tank of fuel but if I pull the coach out of the barn I can position it with the nose a couple of feet below the rear.

Is there any thing else I should be considering??

Thanks

Dick

[Gerald Farris]

Dick,
Do not start the engine with a dry secondary filter, because it will fill the fuel system with air and make starting the engine difficult to impossible. The proper method on your coach is to install the filter dry and loosen the bleeder plug on the secondary filter base, next push the air purge button on the Racor control until liquid diesel fuel runs out the bleeder. Then tighten the bleeder and you are good to go.

Gerald

[Dave Atherton]

Dick, installing a secondary fuel filter dry is correct but you over looked the bleed plug on fuel filter base, thank you Gerald for bringing that point out. Dave would like to add to subject install
Secondary fuel filter on a Cat C-12 has fuel manifold that would allow engine to start and run.
The gear type fuel transfer pump will pull fuel from primary fuel filter but without loosen the hex bleed plug 3 turns, air is locked and cannot open valve infilter base to fuel manifold, and yes
engine will not start. Dave Atherton Retired Cat mechanic

[Edward Buker]

Dick,

Wipe the top edges of the old filters of any loose dirt before you loosen them. You can remove both filters, wipe the filter mating surfaces of the heads, put a little diesel fuel on the filter seals and Orings, replace the secondary filter first to eliminate the possibility of any dirt getting in, then replace the Racor parts and filter. Tighten the filters per instructions, loosen the secondary purge plug, start the purge pump while depressing the schraeder plug on the primary, when fuel emerges from there release the schraeder and continue to run the pump until fuel comes out the secondary air bleed plug, then tighten the plug and stop the purge pump. Start the engine, check for leaks or signs of any air ingress into the Racor screen housing. Just adding some detail to Gerald's post in case you needed it.

Later Ed

[Dick Simonis]

Thanks guys, you have have filled in the missing data points.  Now I'm good to go.

Dick

[Dick Simonis]

OK, got myself in a pickle!  Changing the Rayco went very well but, when I went to purge the air.....I have no power to the Raycor control panel so no purge available.


Does anyone know where the power is supplied from???  Poor coach is sitting out in front of the barn with no chance of starting the engine unless I find the issue or revert to manually filling the whole filter assy.

I wonder if I could come up with a way to pull a vacuum using the bleed valve??

Thanks for any help.

Dick

[Edward Buker]

Dick,

Not sure how all the coaches are wired. May need rear start enabled to power the pump, may also need front ignition in on position. See if that helps.

Later Ed

[Dick Simonis]

BANGING HEAD ON WALL

Of all the stupid things to do, I turned on the remote engine start switch and completely lost the ign. switch.  Once Ed slapped me alongside the noggin with a 2X4 all went well.  Raycor is behaving perfectly but I couldn't get the Cat filter loose.  Reckon someone in the past used a strap wrench and a lot of muscle.  Soooo, back in the barn until I pop over to the parts house for a filter wrench and/or a new strap wrench.

Note to self:  Fuel comes out the Racor bleed valve vigiorously.  Next time I will cut the hose off an old bicycle pump and attach the valve leading into a bucket.  I think the same for the Cat filter.

Thanks for the help.

Dick

[Edward Buker]

Dick,

Cat makes a really high quality strap wrench that uses seat belt material and a metal square drive for a use with a ratchet wrench. The advantage is it fits all larger filters, can get around a filter in a tight space, and grips the filter without slipping. It was not expensive for a quality tool and works well tightening or loosening filters. My local dealer stocked it. I remove it before any oil or diesel fuel begins to leak.

https://www.amazon.com/Caterpillar-Filter-Strap-Wrench-185-3630/dp/B004TR4B7S

Later Ed

[Edward Buker]

Dick and Others,

I had not noticed the Amazon ratings had some dissatisfied customers getting counterfeit strap wrenches. If you choose to buy one get the unit from a Cat dealer. PN is 185-3630. Current price at my local Cat dealer is $31.42 This tool tightens the strap and the tighter the filter the more tension it puts on the strap. My oil filter takes a fair amount of torque to get it to release and this tool has never slipped. I wipe off the filter exterior before I try and loosen it.

Later Ed

[Doug Allman]

Amazon is having and apparently not doing much about it at all in regard to cheap imitations of quality items. There has been numerous articles in regard to this and Amazon says they have a policy against that but they do nothing to verify that the seller is a legitimate authorized seller of the products they want to sell an Amazon.
In several instances there has been up to 40 sellers of knock off products on Amazon for the same product as reported in several interviews with the actual legimate manufacturer of the product.
Amazon has acknowledged it has happened but has not really put in place any substantial method to slow the amount of sellers that are continually in their market place.
Numerous of the knock offs are even using the same packaging with the same logo's and individual names when they list their knock off products.
It appears to be a buyer beware time at Amazon unless you are buying from a know firm that will back the order.

[Joel Ashley]

Some decades ago, I towed my 25' cruiser from Portland to the San Juan Islands for a family reunion, stopping overnight at my sister's near Seattle before heading on to the launch at Anacortes.  I needed to change the Mercruiser's oil filter, but found it pretty much frozen in place.  My brother-in-law was a regional (Northwest) service rep for Oldsmobile Division of GM, and as automotive-savvy as anyone I ever knew.

He had me just force a 14"- 15" screwdriver right through the middle of the filter, maybe with a little help from a hammer.  That provided ideal leverage to loosen the filter easily.  Sure, it was pretty messy, but with a towel around the filter it readily solved the problem.

I'm not saying it's appropriate or advisable in this case or for a diesel fuel filter.  But as a last resort in lieu of success with a good strap wrench, it could be an option.

Joel

[Doug Allman]

Joel, It was exactly as described with a large screwdriver that we finally got the oil filter off the C-12 Cat in our 2004 Marquis the first time we changed it after purchase. Even several young bucks could not get the filter off trying numerous tools until we used the puncture method. Even then we had the can come off the base. To get the base off we used two straight bars in the base holes and another bar to turn them. Room around the filter is not plentiful. Never had the problem since.
I suspect that the coach sat a lot and filters were not changed annually due to low mileage or just sitting in a park so the base nearly mated onto the block. It was a California coach but I do not know if it was kept along the coast, just that the owner also owned a large Yacht. Knowing that I believe salt could have helped this situation develop.