Dodge Demon

300,000 K- was plugged inside.

VADSLRAM

Kind of moot point. In any system of finite size an increase in flow will increase resistance of flow by internal restriction as well as friction. At say 750 rpm/5 gpm it will have one flow characteristic at 2100 rpm/15 gpm there will be a whole different flow profile.
So increasing flow increases restriction which increases pressure.

Ron E

In general terms, this is true. A variable in the mix is the design parameters of the pump. Many pumps will reach a pressure threshold and stall against the resistance. It's all a matter of what the pump was designed to do. For instance, at operating speeds, you can easily stall a heater cage fan (or any other loose tolerance type) by putting your hand over the outlet. It keeps humming, but the air flow has stopped. With a turbo, that won't work. It's in the design. It depends on the blade to housing tolerances among other things. So, an approx pressure limit may be built into a water pump. I don't know that, but it's possible/probable.

SmokenRam

So not to highjack but where is the best place to buy a heater core?? Not too worried on price, i just want one to last. Oh and everyone keeps telling me i should change my condencer(sp) or what ever it called, too if i do the heater corer job???-Chris

Busboy

I'm not sure the best place where you are for the heater core but.... The whole point of this thread is so that you don't have to remove the heater plenum, at the same time disconnecting the air conditioning. It would be at THAT time that some recommend replacing the EVAPORATOR. (That's the AC core inside the heater plenum). If you change the heater core as suggested in the thread, I would wait on replacing the evaporator as it's $400 just for the core up here.

dieselman2300

WHERE do you guys come up with these prices? Napa wants $119 for the evaporator.
http://www.napaonline.com/MasterPage...Core&VehCode=Y

You can get the evap. core from Rockauto.com for $75.00. You guys need to research better.

Anyways, you DO NOT need to disconnect the a/c lines to change the core PROPERLY! Take the extra hour and DO IT RIGHT THE FIRST TIME!!

Edited by Admin

Sorry for the rant, but thats how I feel about it.

Busboy

Everyone is entitled to their opinions.. The $400 for the core was 2 years ago from the dealer. It was the only place I could find one here quickly in this "small" city (about a million people). That was also in Canadian dollars which at the time was about even. I used to be in the AC biz so I have my own freon and equipment so not cost to that.

As for this "mod" all it would take is a little flaring of the pipes on the heater core and running the hoses inside and you have a perfectly good mod. NO hacking at all and for those without freon and vac pump and gauges it's a cheaper way to go. That's MY opinion.
Also in Canada there is $100 excise tax on AC and it's charged on the AC evaporator core.

thumper549

I so doubt they will ever ever leak...How many clamps do you know from the factory on any vehicle ever start to leak...for me, NONE

badme

practice makes perfect. I do them right without cutting in just under 3 hours.

Dodge Demon

But maybe your way aint the "right way",maybe my way by cutting the pipes and way less time is the "right way".

badme

I have one outside right now with the clamp leaking.

slowflyer2112

I'm having heat issues right now (low heat from heater). And need to do this repair. Thanks for the pics. The 2nd gens are not junk just a bad design, look at how both the supply and return tubes come out the top, this means that all of the junk in your cooling system will collect in your heater core and plug it. NAPA makes a bypass spin on filter system that mounts on the heater core supply line that I will be mounting when I install the new core. It runs about 50-100 bucks.

bowhunter96

did mine three years ago and have never retightened the clamps!!for what its worth i have too much to do to take the hvac box out when it is absolutely unnecessary unless the evaporator core is leaking!!my .02!!!

SmokenRam

more info and some pic's on how this works please!!?!?-Thanks chris

cLAYH

Technically if you DO want to "DO IT RIGHT" the A/C lines do need to be undone and the whole box is supposed to be removed from the truck, cleaned out and the Evap inspected. But each to his own I guess.... You took one short cut, I took two.

Hope you're feeling better.....