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Coolant Filter install - 2000 XJ

HOLY COW!!!!!!!!!!!!! :shocked: :eek: :wow:

Das is not normal!

Ya it is. I originally thought it was an oil leak but that proved not to be the case after testing. I'm chocking it up to the previous owner either completely neglecting the coolant system or using dex cool or stop leak.

With that said I do have an update that's kind of bad news. I back flushed the heater core, no brown or rust came out (Guess the filter was working). I connected it all back up to the stock setup and let the Jeep run for a few mins to reach temp before turning the heat on. While I was doing that I added some 50/50 since it didn't look like I fully filled it before (makes sense since it only took 2qrts before). Well the heat still doesn't work and after 30 or so minutes of the jeep sitting there at 220 degrees, only the output hose is kind of warm. The input is flat out cold. This is weird considering it all worked before I installed the filter :(. I tried flowing it on the highway but it's still blowing ice cold and the input hose stays cold now.

The T-stat was replaced about a year ago so I'm pretty sure that's not the issue. Any ideas what's going on?

PS. Not really sure if this is related to anything but I decided to do some googling for Jeep Cherokee Coolant system flow, just to make sure I'm not missing something or tapping into the wrong hoses. I came across this threat http://www.jeepforum.com/forum/f11/heater-hose-placement-344433/ that shows the input and output hoses in a different setup compared to mine. The hoses cross top to bottom. Mine are top to top and bottom to bottom and I'm tapping into the bottom 5/8 hose. I double checked dieselenthusiast's screenshots and his seems to be the same as mine so I'm not sure if this diagram is for older jeeps or what. It's just a little confusing that our input hoses would be coming from the bottom where the water pump pulley is and not the top where the t-stat housing is like in the diagram.
 
I installed a Wix coolant filter kit higher in the engine compartment without any shut off valves inline to the heater core inlet.

There was some improvement after performing before and after electrolysis testing, using a dmm.After installing the coolant filter the coolants dmm voltage readings became very low, within an acceptable voltage. Which leads me to believe after 200,000 miles the coolant filter must be filtering a buildup of paste like iron and metals, trapped in the engine's coolant passages, that overtime is slowly being leached into the coolant.


 
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Alright I think I solved my weird problems. I figured I'd post just in case someone else runs into something similar. So I flushed the heater core back and forth a few more times for good measure but didn't get much out of it. A buddy suggested I fill the overflow reservoir halfway even though my jeep had 3 qts of fluid in it. Turns out there must have been an air pocket somewhere or I let out more fluid than I thought because after doing this most of the fluid in the overflow got sucked into the system. My jeep's temp lowered a lot and now bounces between 190-210F which is kind of what it originally was (It used to stay around 190). Heat and defroster now work as long as I'm not at a dead stop. When I'm stopped it lets out room temp or slightly cold air which sucks but It's livable.

Another thing I noticed that was more so my fault for not paying more attention to the setup and misunderstanding my jeeps coolant flow. I misunderstood what OP did in his tutorial. I've watched a few tutorials on youtube and the most put the coolant filter before the heater core (ie. on the heater core's inlet line). I didn't even realize that OP installed it on the outlet line (ie. after the heater core). So the lines going from the heater core to the coolant filter head were backwards for me. I had the line going from the heater core connected to the outlet on the filter head and the line going from the water pump to the filter head on the inlet. This was obviously preventing fluid from going through the filter but seemed to work when I was diving on the highway...I'm assuming because it just couldn't take all the water pressure build up and had to let some of it through. Once I swapped the lines and drove the jeep a little the heat started flowing from the vents and both lines became hot (as well as the filter). So the filter isn't clogged but I'm sure it will be soon haha.

Thanks for the help guys. I think I'm gonna order a new 11/16" inlet hose and run it through the filter and put the old stock 5/8" outlet hose back. That way the rust and crap gets filtered before entering the heater core.
 
Great write up! Subscribed :)
 
I just flushed mine this weekend as well. Got tons of crap out of the system. When I opened it up to begin with it looked like motor oil coming out because of the amount of rust there was in the system. I used a combo of baking soda and vinegar that breaks the stuff in the heater core up. Mine gets hot as the temp starts to come up during warm up.
 
Older post but not really much info on this wix mount on the net. Anyone have flow problems with the ports being so small? The fitting for the filter is maybe 3/16 and the port drilled in the body of the mount is about 1/4 just by eye. Thats one hell of a flow restriction to me. The filter fitting has the meat to match the other and then some. Drilling the mount bigger could be a problem.
 
Older post but not really much info on this wix mount on the net. Anyone have flow problems with the ports being so small? The fitting for the filter is maybe 3/16 and the port drilled in the body of the mount is about 1/4 just by eye. Thats one hell of a flow restriction to me. The filter fitting has the meat to match the other and then some. Drilling the mount bigger could be a problem.

There's was no flow restriction on mine. The system is spotless clean and the FFD radiator has shown no signs of corrosion.
 
Any problems with the inline trans filter? I don't care for the idea of cutting a steel line and replacing a section (two technically I guess) of it with rubber hose and clamps. Running PSI is around 80-90 and can get up to 200PSI at higher engine rpms. Seems like it would be a weak link for a possible leak. I can't believe two dinky little hose clamps would last for a long time.

Bull!

Transmission cooling lines might get to 50PSI, max.
 
Older post but not really much info on this wix mount on the net. Anyone have flow problems with the ports being so small? The fitting for the filter is maybe 3/16 and the port drilled in the body of the mount is about 1/4 just by eye. Thats one hell of a flow restriction to me. The filter fitting has the meat to match the other and then some. Drilling the mount bigger could be a problem.

This is as designed. It's supposed to be a BYPASS filter for coolant, not a FULL-FLOW filter that happens to be stuck in the bypass line on a heater core.

Best install is to tee off the heater core lines into one of these. Use it properly, and it will work properly. I have these in several of my vehicles.
 
Fluids flow in the path of least resistance. A open hose would favor most if not all the flow vs being forced through a filer. Even more so when the heater circuit is a very low pressure bypass circuit. Hard to think of the filter in a bypass setup on the cooler line realy helping at all.
 
Fluids flow in the path of least resistance. A open hose would favor most if not all the flow vs being forced through a filer. Even more so when the heater circuit is a very low pressure bypass circuit. Hard to think of the filter in a bypass setup on the cooler line realy helping at all.

Two words:

"pressure delta".

Couple that with the idea that we are only trying to syphon off a little bit of the flow at any moment to go through the filter, and you see how it works.

As I said, been running these, and oil bypass, filters for years. They work very well.
 
Yes, but do they have an internal bypass valve so they don't stop flow if clogged?

No, but visual is there all the time, plus you could hook-up a idiot light/ pressure gauge to monitor on the road!
 
Hose clamps on the trans line are 100% fine. How do you think most people including myself install auxiliary coolers? Very few are hard lined that i have seen.
 
I do precisely the same as Mach2nh. I've been doing it for, oh, 27 years now. Never a problem.
 
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