Heater core questions

[jeepontruckin]

So next week I plan on replacing the heater core in our 400,000 miles 04. I've done my homework but I have a couple quick questions that I was hoping that you guys could help me answer. I've searched around and realize that the AC system has to be dismantled in order to remove the dash of my liberty.

I was wondering if anybody has ever successfully replace the heater core without discharging the a/c system and if so was it worth the extra effort to keep the AC system intact? Its not that I can't reassemble the AC system its just that I don't have immediate access to the tools any more.

My second question is relatively simple. I plan on replacing the heater hoses while replacing the heater core but when I went to price them all the premade hoses were about $10 or so a piece. My question is Should I go ahead and spend the money on the premade hoses or would it be better to just save some money and make the hoses myself with bulk heater hose? Yes I already know it does seem like I am penny pinching but my Jeep has a relatively high amount of miles and penny pinching is what's gotten this Jeep as far as it has. Any help would be greatly appreciated thank you

 

[MarkJ]

Now I have not done this on my Lib, and it's too cold to run out and look at mine... However, I would look at the heater hoses like I do on any car. If the bend radius is relatively large and you can replicate them with bulk hose (of a good variety - I stay with NAPA for consistent quality), then I would use bulk. Bend the bulk hose to the same angle and if it is anywhere even close to kinking (when the hose gets hot it will kink even easier) I would buy the OEM hose. Make sure when you form the hoses there is no way they will rub against anything. And lastly, just how much will you really save against the $10 per hose price? Put on new clamps if needed. Tighten them up and let them sit an hour then re-check. If there is any way you can run the engine up to operating temp while burping the air out of the system and checking for leaks without closing the dash, do so. Then let it all cool off and re-check those clamps before finishing it off.

 

[tjkj2002]

Both heater hoses on a KJ have both rubber and metal parts,you need the specific premade hose as "bulk" hose will not work.


As for the AC you must evac the AC system or that HVAC box is not coming out,no way around that.

 

[jeepguy4276]

I replaced mine last spring. You need proper hoses and the ac has to be drained. It's a pita job, mostly because of the millions of nuts, bolts, and screws.

 

[jeepontruckin]

Thank you very much for the quick replies guys! I appreciate the information,It was exactly what I needed to know. I guess in the long run it really wouldn't save me any money by getting bulk hose. I will go ahead and get the premade hoses.

It may take me a week or so but I will post up with the results of this project.
Thanks again

A little off topic but while I have the AC system evacuated is there any maintenance that you guys could recommend? I plan on replacing the Schrader valves while the system is down is there anything else that I should look at?