[MWP]

Part 1: get all the parts + test-fit.

I flush, I backflush, and I can’t get the [email protected]# knock sensors out. I know I need to get someone to remove them to flush out the settled crud in the block, but a coolant filter will be a fun experiment anyway. Thanks to this old Smelonas thread for the location idea: A coolant filter how to...

Two short hoses will tee into the heater hoses in front, sammiching the radiator hose but not blocking or interfering with anything. Careful connector lengths will keep the heater hoses off the belt-drive.

Parts:

--ACDelco coolant filter base 25010047, cast aluminum, same as Baldwin CFB5000 (no AC logo). New ones are from China. Found this Michigan-made NOS one on Ebay for less than the new ones. Should be plenty of them in junkyards, too. Right now I’ve got the extra ports plugged, but it would be convenient for a low pressure sensor (like you might want with an EWP).

--Wix 524069 filter, no chemical additives, made in NC. It’s the shorter version of Napa 4070.

--MidAmerica NPT 3/8-18 fittings, made in US
29ESB-86 single male hose barb for half-inch ID hose
2945-86 elbow for half-inch ID hose
29AL-6 countersunk plug (2)

--Four Seasons 84543 5/8 x 1/2 x 5/8 metal heater hose 90-degree tees (2).
Y fittings would improve flow through the filter, but I haven’t found metal Ys in the right size yet, only plastic (like Kat 28111, available many places). I trust metal more.

--Gates 28410 half-inch ID heater hose, 2 feet.

--Heat-shrink hose clamps—new for me. Clean look and easy.
Gates PowerGrip 32925 for hose w/ OD min. 15/16” (need 4 for the 5/8 ID heater hoses)
32922 fits 13/16 to 15/16 OD hose (used 4 for the 5/8 ID heater hoses on the tees, and 4 for the 1/2 ID filter hoses. A filter hose with a wall any thinner than the Gates 28410 would need a smaller shrink clamp.)

--Two 3/8” bolts and nylock nuts to mount the filter base. I bought 1.25 inch ones and cut them down flush with the nuts. Nothing hits the radiator.

--The filter assembly is almost 3 pounds without hoses and coolant, so I used a piece of 3/4 x 3/4 x 1/16 aluminum angle to reinforce the plastic radiator cover, plus two #8 x 3/4 panhead screws, washers, and lock nuts. Trimmed bolts after assembly.

Next step: To restrict flexing/vibration, make a support bracket from the filter mount down to somewhere on the fan bracket. After that, backflush the heater core and splice in the filter. More pics as it comes together, and then I’ll put some miles on and see what gets filtered out.

 

[1slow96]

I considered (and,may still) install one on the inside frame rail beside transmission. Heater hose leading to core would be extended, and hose leading from the filter housing would then supply the heater core.

 

[oldhead]

I installed a filter and revirsed the flow on the heater about 5 years ago. everthing worked good... the same filter has been on it for 4 years Oldhead PS; The plastric T fitting broke 2 months ago and i made one out of 1/2" copper plumbing parts love my wagon oldhead

 

[Dezrat]

Greetings MWP,
Please update this coolant filter test after awhile. Maybe cut the filter open report findings.
I am curious if you find casting sand or any mud like materials. I have always felt these blocks have casting sand or particles in them. Thanks and good luck, Dezrat

 

[MWP]

Dezrat--thanks, will do.

Part 2: Put it all together

I backflushed some nasty stuff out, and sacrificed the existing black heater hoses to mock-up the tee locations and filter hoses. Yes, I did cut up an NOS set of 9C1 heater hoses for the permanent installation. A little shield worked well with a heat gun for the Gates shrink clamps on the tees. First time I've used them and so far I'm a convert. Turns out the Gates 32922 (same as NAPA 42922) shrink clamp works fine on the heater hoses as well as the smaller filter hoses, so the larger one listed in Post #1 isn't needed. I kept the GM spring clamps on the reservoir, heater core, and water pump. Also added a magnet on the bottom of the filter with a drop of red Loctite for overkill.

Replaced the 178K-mile crossover/steam pipe as well. You can see the corrosion in it, and the scale that was settling in the heater inlet hose (maybe 4-5 years old, with a couple of partial (no knock sensor removal) coolant changes in that time).

No leaks, nothing's twisted, and there's more clearance than before to the belt/pulleys. The filter heated up fast, so there's good flow. Just have to remember not to put my hand on it after driving.

Next part: Drive a week then cut open the filter. Kinda looking forward to it.

 

[1slow96]

Guess I don't "get" the reason(s) for installing tee(s) instead of having heater hose directly into the filter. Then the outlet hose continuing to heater core. Filtering all coolant entering the heater core seems of more value to me.

 

[MWP]

Guess I don't "get" the reason(s) for installing tee(s) instead of having heater hose directly into the filter. Then the outlet hose continuing to heater core. Filtering all coolant entering the heater core seems of more value to me.

I really wanted to do that. As you say it would filter all of it, and it would be simpler. But, restrictions in the filter base and filter would cut the flow to the heater core a lot. The filter base inlet and outlet fittings are only 3/8", so the cross-section is about a third of the heater hose. And, the coolant filter has a center restrictor with a small opening (not like an oil filter). It's even smaller than the opening in the flow restrictor in the heater inlet hose.

To do it in the hose, there is at least one aftermarket base with high flow, but ouch, the price...
IPR High Flow Coolant Filter Ford 6.0

 

[1slow96]

Plenty of filter bases with up to 1/2" NPT ports,along with plenty of coolant spec filters. One could always experiment with different hose routing. Not committed one way or the other though my filter will be inside the passenger side frame rail. I use AN hose/fittings so changing configuration is somewhat easier for me.

 

[Sinister]

Big trucks use coolant filters and many of them are mounted directly to the engine block. Others are add on parts with small hoses and are just plumbed into random spots.

They work well but on engines that are full of crud they do nothing but quickly clog the filter and become useless.

 

[MWP]

Part 3 Test drive, then watch the work-list expand...

For giggles, I sawed the new coolant filter open after an initial 10-mile errand. The stuff on the sides is from the hacksaw, but at the bottom you can see some iron bits pulled from the coolant by the external filter magnet. And…whoa, what’s that faint smell of antifreeze? Oooh, droplets from the back of the 80K miles water pump. Great. Glad the AIR pump bracket was already gone. The bearing was coming to pieces, so I put in a rebuilt NAPA pump. Thanks to forum advice, I drilled out a 45-degree zerk fitting, drilled out the weep hole just enough to screw the zerk into the aluminum pump, and added a clear drain hose with a homemade bracket to clear the crank balancer.

With the WP out, that darn 80K Optispark was accessible. Okay, sigh, better take a look inside. Didn’t have a long #6 Torx socket, so I had to grind down the sides of the socket I did have to reach the two deep cap bolts. Yep, burned rotor tip and inner terminals. Got a new rotor and cap, loctited the various small screws, added a touch of silicone sealant to the seals. The Opti bearing is a little wobbly, but there’s not much I can do about that right now.

The vent hoses were replaced in the past and work well, but I updated the rubber sections with some silicone pieces I had in the drawer from an LT1 vacuum line kit I bought years ago. Replaced the WP/opti seals in the timing cover, too. The timing cover gasket and crank seal are great, so I did not feel guilty about skipping them.

I hope the new parts will last, and that the opti bearing and crankshaft seal will last for a couple of years. Then I can do them and several things together, including a new timing set, new plug wires (those are fun, aren’t they?), and maybe an electric WP.

The forum is great for preparing for such tasks:
Watching Goldmaster’s WP/Opti videos reminded me of some details:
96 Impala Camshaft and Optispark Seals Replace Video

And, I still had the great WP seal tool from last time:
LT1 Water Pump Seal Tools- Small Supply (30) $12.50 each

Maintenance and repairs mean time and some frustration, but there is great satisfaction in fixing stuff, keeping machinery running, making new things. As Thanksgiving rolls around, I am grateful for my father who saw this bug in me. In my modest garage, the shop tool I treasure the most is the one I still use the most—a little red-box K-Mart socket set he gave me more than four decades ago. I eventually broke the original ratchet and one socket, but it has been one hell of a present.

On Thursday let’s all raise a glass in memory of the people in our lives who showed us we could learn to fix things, which really taught us so much more.

Next part: drive longer and open up more filters.

 

[MWP]

Part 4: Coolant filter after 320 miles

Haven't driven much this past month, but I cut open the coolant filter this afternoon with tin snips so there would not be misleading hacksaw dust. Here's a mere 320 miles worth of bypass filtering, not including the fine particles trapped by the filter pleats. No pic for that, but the pleats were already brown. I think I'll leave the next filter on for a couple thousand miles before taking a look.

 

[MWP]

Part 5: 3rd coolant filter with 1200 miles

Not much driving these days with Covid. 1200 miles on my daily driver in 3 months. Pulled off filter number three this morning. Rust-stained pleats, and less but still significant grit in the magnetized bottom. Guess I'll leave the new one on until 2022.

.

 

[MWP]

Part 6: Filter #4 with 5000 miles

One year after adding the plumbing, here's the most recent filter. Rust-colored pleats (no pic) and more iron grit.

 

[1slow96]

Installed a NAPA/WIX coolant filter on my 1998 K1500 pick up as described previous with 100% filtration to the heater core. Used 3/8npt to AN-10 fittings ,but still concerned about the quite small (maybe 1/16") restricted passage inside the output port. Driving truck tonight with sub-freezing temps ,and 180 stat. I had heat quality/quantity seemed unaffected. Which frankly surprised me ,as I was prepared to bypass some volume of heater hose coolant from filter to heater core ,but for now it really seemed fine...

 

[Buffalololer]

I really wanted to do that. As you say it would filter all of it, and it would be simpler. But, restrictions in the filter base and filter would cut the flow to the heater core a lot. The filter base inlet and outlet fittings are only 3/8", so the cross-section is about a third of the heater hose. And, the coolant filter has a center restrictor with a small opening (not like an oil filter). It's even smaller than the opening in the flow restrictor in the heater inlet hose.

To do it in the hose, there is at least one aftermarket base with high flow, but ouch, the price...
IPR High Flow Coolant Filter Ford 6.0

I just installed that kit this weekend, and although I haven't been driving around and I won't be until the weather gets better (they salt the road in Germany), I started the car up ad ran it for a bit and the filter and hose going to the heater core got pretty hot, so I assume the flow is sufficient. I plan to install a ball valve to enable filter removal with less drain back.

Also, a previous owner relocated the battery to the trunk so I put the assembly where the battery used to be.

 

[MWP]

Part 7: Coolant filter #5 with one year, 6000 miles

Two years after adding the bypass loop, it's doing its thing. Yuck. In hindsight I would go with 100% filtration in-series. I'm sure a lot of this is ancient crud from the block since I never could get the knock sensors out.