i recently installed a coolant filter on a low mileage 6.9 that had been garaged for 10 years without being driven.
i installed it on the hose going from the head, to the heater core. plan was, i would know when the filter is getting plugged when heat output dropped off in the cab.

sure enough. the first filter lasted less than a week. ( i had drained and amateur flushed the cooling system prior)
second filter a month, thrid, one month. noticed today that i was cold, so, new filter, warm now.

here is the question. how many more filters till the sludge and gunk decrease? answer , no one knows.
and have all of my engines had this filthy gunk floating around in them?
if so, im looking at buying filters by the case....

whhat experiences have you had with coolant filters?

 

What does the clogging stuff look like? Is it like white solid or like sludge?

 

brown mud initially, and later a blackish goo.

i need to buy a can opener , opening them up to give u a better answer

 

The brown mud is iron oxides and silicates. The black goo could be oil residues and silicates. (Suspect a small oil leak in the oil cooler)

 

.... and i have the 4071 filter with sca's in it. no idea what color the sca are. at any rate i have a very unclean cooling system.

oinsgould also show up in the radiator tank, so far so good.
and no coolant in the oil, so far so good

 

I replaced my first filter on 11/28/2015 after about a year, it was nasty. Took that long to noticeably decrease heater output. On my second filter now and thanks for reminding me I should replace it and check my SCA level. I'll cut this second one open and compare. Here's a picture of the first one...

 

for a full year thst don't look so bad.
so u put your inline in fron of the heater core too.
only logical place I suppose.

 

So the flow direction is from the block, to the core, and then back to the water pump?

And what setups do you guys run? Seems like a smart thing to do

 

With the diesel its especially smart as debris in the coolant can plug oil cooler holes.

tthe filter in my rig sits between the engine and heater core. its a napa part filter housing and filter # 4071.
filters are expensive. 18.00 each
rust scale, mineral deposits, casting sand, gasket material all end up in thecoolant. this ultimately will filter most of it out.
TIP; ANTI FREEZE HAS GOTTEN TO BE VERY COSTLY. MOST WRECKING YARDS WILL GIVE YOU AS MUCH AS YOU WANT FOR FREE.
take it home filter it use oil absorb mat to skim off any oil residue , and u will be in good shape for years to come. i get mine from a big truk wrecker 55 gallons at a time. thus i get diesel coolant, un mixed with orange or pink or whatever. coolant never goes bad,

 

When you install a coolant filter make sure you install it as a bypass filter. If the filter clogs it won't prevent flow to your heater core.

Here's a good write up on installing a coolant filter.

https://www.oilburners.net/articles/coolfilter4.html

 

You do not need to install it as a bypass filter at all. Restricting flow to the heater does nothing but reduce the BTU out put of the heater core. And in line gives a bit a restriction and will help with heater core longevity. The write up although well done is incorrect in some of it's assumptions.

 

Recall the factory fitting from the passenger head in our trucks has a restrictor in it. The restrictor is rubber, mine was just about gone, but the restrictor in the filter base is about the same size. I would rather filter more coolant and keep my new expensive FoMoCo heater core clean. Put the filter ahead of the heater core to keep it clean, no sense putting it after the core.

 

Yup Ford had heater core flow/pressure reducing restrictors in many vehicles in the 1980's. This was to lengthen the life of the heater cores and help with engine cooling in certain situations.


So putting the filter in line before the heater core line is not bad thing.
Putting it after the heater core is sort of useless.

 

Hmmm... I didn't know used restrictions before the heater core in their vehicles. Thanks for the info.


One good idea from the write up I linked is to use a ball valve on the IN and OUT of the coolant filter. This allows you to close off the filter when changing it so you don't loose all of your coolant.

 

I don't think the Ford F-Series had one.

The only application I am aware of that used a heater hose restriction to the heater core was the mid 1980s Mustang GT. The reason was for high RPM usage.