Coolant System Filter?

[Jeffncs]

I removed and manually flushed the radiator on my 258 CJ7 with a garden hose last weekend and removed a bunch of rust and debris. I made the mistake of not planning my next move and reinstalled the radiator and refilled before adding an inline filter to the system. Now I’m realizing that i was a short sighted and once again have an engine that’s running hot. I’m going to drain, remove, flush and reinstall the radiator again. This time I’m planning for a filter that will make life easier to maintain the radiator flow.

1. Should I take the radiator to a shop to have them flush it professionally? Or do you think flushing it upside down and draining repeatedly will be adequate to restore coolant passage flow? I got a lot out that way last weekend, but was that enough?

2. Do you recommend a specific brand or style filter housing/assembly? I see some are designed with a removable cap which enables access to a filter. Others are truly inline and require breaking the line to clear the filter. Thoughts?

3. I’ve read good and bad about the coolant system flushes... I have a newer radiator and a new heater core... should I try one of them too?

 

[shelby27604]

I have seen filters on diesel cooling systems, but not first hand on any gassers.....

In my experience, if the rad was filled with rust and debris it is toast and likely the reason the Jeep is still running hot, you can have a shop rod it out, but for that cost, just put a new one unit in there.

For heater core, you can bypass it or in a pinch I have filled my system with CLR / water mix, pulled the thermostat and run it around town for a few hours.

Als don't discount the value of a back flush kit (readily available at walmart wa auto parts stores)

 

[Tim C]

I bought a napa 4070 I think screw on coolant filter and matching head to use temporarily on my 67 Fairlane with the new engine since I was using the old radiator and heater. Mine wasn't bad, just extra precaution. I just put it in a heater hose and drove the car 1000 miles, changing the filter (maybe twice tops) when there would be a noticable drop in temp pre/post filter. After that I put it on my dad's 67 c10 because his coolant was rusty and brown. It clogged the filter nearly every 100 miles. His heat would actually quit in 20 miles but I'd go close to 50 or 60 before changing filters. After about 500 miles of that I did a normal drain, flush with water, run til stat opens, then drain and refill with coolant and left the filter in line for another 500 miles with far less filter changes, because most of the debris was out by then.

By putting it in the heater line it's a direct filter so it stops up faster but filters faster too. I didn't cut the heater hose, just took it off the intake, put that to the outlet of the filter and a new jumper hose to the filter inlet. Heater flow is intake/head to core, return core to water pump or radiator BTW.

On my old 6.0 power stroke I used the same filter head and filters but they were spliced into a small vent line from the intake to the overflow reservoir. Which is basically a bypass filter. That's what you want for a permanent mounted filter as it's getting stopped up won't affect heat or engine temp. You can duplicate that by having the filter tee in between bthe heater hoses like an H with a slight restriction after the H on the leg going to the core. The restriction will force some coolant to bypass the heater and flow through the filter.

If you just want to clean the coolant then remove the setup you can just put it in the heater in series.

I would pinch off the hoses with needle nose vise grips or hose pinching pliers then change filter then in crimp. Little mess and only needed a qt or so fluid added after.

Filters were less than $20 and the filter head from napa was around $40. Plus misc brass nipples.

 

[shelby27604]

When dealing with our current temps, don't forget to make sure the rest of the system is in tip top shape, I would say do a few flushes with the current radiator (so the new one doesn't become the "filter" for remaining debris).
Check and or replace the thermostat, water pump, fan clutch (if equipped) and make sure your belts aren't slipping, also make sure you have a fan shroud.....so many people discount how important they are until temps hit the 90's!

 

[getstucksome]

When dealing with our current temps, don't forget to make sure the rest of the system is in tip top shape, I would say do a few flushes with the current radiator (so the new one doesn't become the "filter" for remaining debris).
Check and or replace the thermostat, water pump, fan clutch (if equipped) and make sure your belts aren't slipping, also make sure you have a fan shroud.....so many people discount how important they are until temps hit the 90's!

This. I would be more concerned with all of the junk left in the block/heater core/etc. if the radiator was as bad as you say it was when flushing it.

 

[Jeffncs]

The cooling system was REAL BAD. Here’s a pic from the first time I dropped the coolant

Rust and TX clay...

 

[Jeffncs]

The engine block is still sloughing off rust flakes, clogging the radiator.

it’s a new looking rad though and still had the labels on it. Shame I can’t try to save it.

 

[shelby27604]

Buy a back flush kit, pull the thermostat out and do a couple of deep flushes (according to capacity and instructions on the Preston's flush bottle).
If you do those two things (and everything else checks good, fluids run clean AND the Jeep isn't overheating) toss in a new thermostat, fill with 50/50 and see how it does before you throw a new radiator at it.
If with no thermostat and a few good flushes you are still running hot, radiator is clogged, if you throw in a good thermostat and it starts to run hot, I would also suspect the radiator still (if all of the above has been checked)