Today ongoing to get a new T-stat for the 89 XJ 4x4 auto 4.0 that some of us have been discussing in another thread.

I'm also going to get a some coolant flusher and flush it out.

I'm also going to flush heater core too with CLR (seen it another thread) at some point after I flush the cooling system first.

So should I?
1. Flush with old t-stat in?
2. Take out old t-stat then put back together then flush?
3. Put in new t-stat then flush?(pretty sure this isn't the way but had to ask)

Now after I flush the coolant system I am going to flush just the heater core with CLR to ensure its extra clean. Seen this done in another thread.

So which should I do 1,2,3?
And does what I'm going to do sound good enough?

PS I feel like almost an annoyance asking for input on all these subjects but I guess that's what the forum is for.

 

if you have not already you should pitch the heater control valve on the heater core lines. this part is known to break very easily. It will also make it a lot easier to flush the system because the coolant will always be flowing into and out of the heater core.

 

Here is a procedure I saved that was posted here. Can't remember who though.


"Remove the top radiator hose and top heater hose from the t-stat cover. Remove the bottom radiator hose from the water pump (very easy if the plastic air filter box is removed 1st). Stick a garden hose in the heater hose and flush. Stick the garden hose on the heater hose nipple on the thermostat cover and flush. Stick garden hose in the top radiator hose and flush. All areas are now flushed without crud moving from one place and lodging in another."

 

Great. Thank you. So do a preliminary flush before the actual flush to prevent lodging. I will most surely do this.

 

Yes, though to be honest, I don't think I'd even bother with a flush kit after doing the hose flush as described above. Wouldn't hurt, though, especially if there's scale in the radiator or heater core.

 

I am not a fan of using flushing chemicals.

 

Already ran into a problem 2 minutes after starting.

I followed the two hoses going to front of engine all the way to the firewall and I took the clamp off top hose and cannot get it to move and I'm scared to pull to hard because just after the hose ends in turns to metal tubing and I'm scared ill break it.




This is the two hoses that I followed back to firewall.







This is the top hose going into the firewall. As you can see where it starts turning it turns into metal tube. Also it drops down and runs to another hose that runs into over flow jug. I am scared to pull with hands or pliers out of fear of breaking the metal part.


It feels like even when I know how to do something it's just always so difficult. Maybe it's me. Maybe it's everybody.

It has to be a trick or something to get the hose to come off. It's so aggravating it just makes me want to give up and not even try. It's a simple heater core flush and I'm having trouble.

 

Your heater core is behind the firewall and two metal necks stick out towards the engine bay. Those two hoses go on them. I've had to take a razor knife and carefully cut through the hose to get it off then replace with new. Its old and should be replaced.

 

These hoses are like new so I don't want to spend extra money. Second I know there is a set of pliers with the hook made to pull off hoses but I can't seem to find my daddy's(he died a year ago this month) nowhere and I know he had them.

I guess I'll try making a small slit.

 

SORRY about your dad.


Got to be careful not to grip to hard if using pliers or such. It's easy to deform those necks. If the hose is like new it shouldn't be that hard to remove. I've found some of those where a sealant was put on before the hose. Talk about hard to get off.

 

Okay I got it off. I had to cut it so ill be buying new ones or going to scrap yard or something.

Anyway either I'm npt good at flushing or the hoses are almost clogged shut. I put a funnel in the top hose and put the hose pipe into funnel and at first it just trickled out the other hose. It was dark dark brown. It's really messy and it got wet around my engine and I hope that doesn't hurt nothing.


I don't think I'm doing something right though but here's a picture of my set up.




As you can see the funnel is in the hose up above. It runs into the thermostat.<br/><br/>The other hose(s) are placed in a jar