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Coolant Filter install - 2000 XJ

Ok, just to clarify... The inlet of the heater core tees into the inlet of the filter, the outlet of the filter tees into the outlet of the heater core.

^^I am just getting around to doing mine, and this is how the instructions said to plumb it. I am waiting for two metal tees from NAPA. I will tee off the heater hose coming from the thermostat and then to the inlet of the filter. From the outlet of the filter, I will tee into the heater hose going back to the water pump fitting. I guess if the filter and tee'd hoses get hot, it's working:spin1:We shall see.
 
The coolant gets filtered before entering into the heater core.
Are you sure of that? The hose coming of the t-stat housing is the pressure/into the core. The one on the water pump is the return. From what I can see you are tied into the return.
 
Are you sure of that? The hose coming of the t-stat housing is the pressure/into the core. The one on the water pump is the return. From what I can see you are tied into the return.

Yeah, I'm pretty sure. We routed the inlet coming from the thermostat housing. Not that it really matters where the filter is placed, but I wanted to filter before the coolant went into the heater core. There's always a chance that I got them reversed, though!

On a side note: I would like to cut open the coolant filter sometime this summer to see what she looks like. If I do, I will post pictures!
 
Not that it really matters where the filter is placed, but I wanted to filter before the coolant went into the heater core. There's always a chance that I got them reversed, though!
Yeah, not much a a difference where the filter is. It just looks from your pics like its going to the water pump.

On a side note: I would like to cut open the coolant filter sometime this summer to see what she looks like. If I do, I will post pictures!
That would be a great idea. How many miles has it been on for currently?
 
That would be a great idea. How many miles has it been on for currently?

As recommended by Donaldson, I change the filter annually. I'm currently averaging (approximately) 5,000 miles per year on the XJ. Even though that is low mileage, the majority of those miles have been hard miles (low speeds, towing, dusty conditions, etc.) This will be the 3rd filter change since installing the new radiator.
 
OK I am going to sneak in a question. Is the coolant in 1990 XJ 4.0 engine forced to go to back cylinder through its travel or is it just passively expected to cool that area through wishfull thinking? The only other possibility is that I have blocked water jacket! mine over heats in funny way. It boils over before the temp goes past 180 F idling, and I see bubbles in reservoir, then when it cools more it sucks the coolant all back in the engine, like there was a big steam bubble. it is better when driving but temp still goes high.
Can anybody guide in the right direction? I still cant start a thread thats why I had to ask this way.
 
Is the coolant in 1990 XJ 4.0 engine forced to go to back cylinder through its travel or is it just passively expected to cool that area through wishfull thinking?

Yes, it is supposed to go through the head. However, if you have a blockage before the temp sensor (had this problem) it won't indicate the overheat, but you'll see coolant come out areas it shouldn't.
 
Has anyone cut open a filter yet to see what this is catching?

I have not cut open a filter (yet), but I can only imagine how much it's keeping the system clean. When I bought the Jeep, it had a very dirty cooling system. I added a coolant filter when I installed a new radiator. No matter how many times you flush the system, there will always be some particles floating around. The system cleaned up quickly and continues to stay clean.
 
Hey guys. So I just went through this MOD on my 99 XJ and am running into a bit of a problem. My defrost and heat are almost non-existent now. After flooring it on the highway I have mild heat but defrost is still blowing cold. I'm also noticing the usual 190 engine temp that my jeep has is now 213ish, give or take a few degrees. It'll drop a little when I'm driving on the highway but as soon as I'm off it, it'll start creeping back up to 210-215. I haven't let it sit yet to see if it overheats.

I'm running the exact setup as the original poster, minus the shut off valves and other brass fittings. The inlet hose going from the pump to the filter to the heater core is not very warm (room temp I guess) nor is the new filter, but the outlet hose coming from the heater core back to the pump is the usual hot to touch temp. So this shows that the heater core is heating something. This is the usual symptoms I run into when I have a blocked heater core, only the inlet and outlet are usually hot. I'm pretty sure the heater core is not blocked as I had heat and defrost before I did this mod.

I'm also pretty sure I have it all connected correctly. The inlet from the pump is connected to the inlet on the filter head. The outlet from the filter head is connected to the inlet on the heater core (ie. I just disconnected the 5/8" heater core inlet and connected it to the filter head).

My only guess is that the filter is impeding the coolant flow. Has anyone else run into this issue and what was your solution? I do have a lot of rust and crap in my system thanks to the previous owner neglecting it but I made sure to run a good long flush before I did this so there wouldn't be any blockages. I guess my next step is to disconnect the hoses and directly connect from the pump back into the heater core to see if the filter is, in fact, causing the issue. I'll keep you all posted.
 
It's possible that your filter is already clogged. It doesn't take long to clog a filter if you have a dirty system.
 
It's possible that your filter is already clogged. It doesn't take long to clog a filter if you have a dirty system.

I doubt it's that. When I flushed I was getting clear water so i'd expect at least a week or two before it fully gets clogged with rust scale.

@trippled wouldn't the air pocket have moved to the overflow after driving the vehicle for 40 mins? I made sure to squeeze all the hoses while the engine was running to get the air out but I guess that might still be the issue.
 
I doubt it's that. When I flushed I was getting clear water so i'd expect at least a week or two before it fully gets clogged with rust scale.

I was basing my comment on your comment, "I do have a lot of rust and crap in my system" If you have a lot of rust and debris in your system, it can clog the filter pretty quickly, especially if using a smaller micron filter such as the Donaldson filter. Or, if this is your initial cleanup with the very first filter, then it's recommend that you change it within the first thousand miles or so on a dirty system. After the first filter, then you can move to longer intervals (10,000 mile/1 year intervals). To check for a clogged filter, you can always do the hand test. If the filter is too hot to touch, then it's probably not clogged. If you can touch the filter and hold onto it, then it's a good sign that it's clogged.
 
I doubt it's that. When I flushed I was getting clear water so i'd expect at least a week or two before it fully gets clogged with rust scale.

@trippled wouldn't the air pocket have moved to the overflow after driving the vehicle for 40 mins? I made sure to squeeze all the hoses while the engine was running to get the air out but I guess that might still be the issue.

No. They can be pretty stubborn sometimes. You can try jacking the front end up as high as you can and running with the Cap off. Or pull a vacuum on the system. Sometimes running the engine and pulling the heater hose off some to bleed coolant thru will work (cold engine of course.) Some Audis had a special heater hose for that actually.
 
I was basing my comment on your comment, "I do have a lot of rust and crap in my system" If you have a lot of rust and debris in your system, it can clog the filter pretty quickly, especially if using a smaller micron filter such as the Donaldson filter. Or, if this is your initial cleanup with the very first filter, then it's recommend that you change it within the first thousand miles or so on a dirty system. After the first filter, then you can move to longer intervals (10,000 mile/1 year intervals). To check for a clogged filter, you can always do the hand test. If the filter is too hot to touch, then it's probably not clogged. If you can touch the filter and hold onto it, then it's a good sign that it's clogged.

Gotcha. I'm using a Luber Finer LFW4685. I cant find any information on the micron rating for it but I'm guessing it's the same as Wix.

So today I drove around more, alternating between the defroster and the heat. I'm noticing it's still blowing cooler air but it is starting to get warmer compared to yesterday. The jeep is still running hotter than usual though. The filter is also warm to the touch and so is the intake hoses. The output hose is still the usual hot to touch. I was going to try going back to the stock setup today to rule out the heater core but I'm short on time so I'll have to wait until tomorrow. I did park on a hill with the engine facing up hill, undid the radiator cap, and turned on the jeep while squeezing the hoses again.
 
If you undo any hoses, back flush the heater core.
 
Yea I should've said that as well. If you had that much crap in the coolant I wouldn't be surprised if the heater core is getting plugged up. Youd be amazed how much junk will be inside those.
Or how fast it can get lodged in the core. An old timer told me to bypass the heater core whenever I flush the cooling system.
 
I usually backflush the heater core separate but ya I'll be sure to flush it again. I did it a week ago which is why I don't think it's blocked. It usually takes 4 months before it's blocked on me.
 
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