ok, guys, found bunch of diffrent descriptions and it could not be more confusing ..heh heh
here's what I think, and I maybe wrong again...though
but after looking at various diagrams and "descriptions" I think I figured where "the confusion" may come from.
Some descriptions would state something like: "the hot coolant flows from water pump to heater core through valve and then returns to engine... "
so if you look and you see one hose goes to w-pump and the other to t-stat, you may think it flows from pump - to t-stat housing. That what I though ...

So what I think it is - is this: it does flow from the pump BUT - TROUGH !!!the thermostat housing - THEN out from housing - through the valve - to heaterbcore - from core back through the valve - down to water pump. And this is the heater cycle. This cycle as I understand is "active" regardless of t-stat open/close state.
When the heater valve is open the hot coolant flows from w-pump - through t-stat housing - from t-stat housing to heater valve - from valve to heater core-from heater core-back to heater valve-from heater valve down to water pump.
If the heater valve closed, then hot coolant flows from water pump - through t-stat housing - out from t-stat housing to heater valve - makes "u-turn" in closed valve - from heater valve - down to water pump.

When the t-stat opens, then the hot coolan also flows through upper hose to radiator (which makes the upper hose hot) ... and then from radiator through lower hose to water pump. That is the radiator cycle.
And then of cource there's engine cycle - cold coolant from water pump - through engine - hot coolant - to - water pump.
This kind of makes sense to me.
I've found a diagram here, that sort of close to what I think it is like: http://www.automotivecoolingservices...ng_system.html

please correct me if I am completely missing something

 

This is a fantastic write up! However, im curious, would there be any negative effects if one were to just bypass that valve all together and go straight to the core?

 

I have not tried this.
As I understand "bypassing" the valve is the same as having the valve open all the time. So you get the core heated up as soon as the coolant gets hot. So for one you always have hot core inside the cab. If you have your fan off, then you still have the cab heated a bit. This maybe undesirable during hot summer. You can turn the fan on and put the temerature control to COOL and have somewhat mostly "cold" air blowing in, but as I understand it's still going to be somewhat warm.
During cold winter I'd say bypassing the valve is ok.
again, I have not tried this myself, so don't know for sure.

 

I see. Well, then the temp fix I plan on throwing in will be perfect. Its called zip tying the valve open for the winter, and not worrying about it in the summer because I wont be driving it anyway. Thanks doc.

Well... that definitely did NOT work at all. As a matter of fact, when I zip tied the arm of the valve up, it made all signs of warmth (what little there are) disappear completely. I cut the tie off, and the little bit of warmth I was getting returned.

This tells me a couple things. One... I have no clue how that valve works at all. And two, I have a feeling my issue isnt the valve. I did make one observation, and that was that there is definitely NO vacuum at that valve coming from the line that goes from the valve to the core.

Kinda stumped at the moment.

EDITED: After reading through this post again, I think there is no vacuum there because I have the controls all the way over to heat. So, again, I dont think my issue is the valve at all. I think its something else. So, i guess the next move is a core flush?

By the way doc, what did you use to flush your core? I see a couple garden hoses. Is that all you did? How did you attach them to your core? Was there some kind of adapter you bought?

EDITED: NVM, I did some more searching and reading and found what I'll need to flush it. Hope this fixes my issue.

 

I've used 5/8" copper pipe cuts (just happen to have them around) to "connect" the garden hose with core hoses , 5/8" pipe fits nicely inside garden hose and those core/valve hoses, I actually clamped them, But I don't really thing it was needed.
I think you can connect garden hoses to core fittings, but I didn't remove the hoses from core fittings, mine are so freaking tight there even without clamps, when I was trying to twist them off...they didn't want to move ...grrrrrrrrrrrr, so I just said to myself - forget it...I didn't want to brake those hoses by forcing it.

how's going?

 

Gotcha. Yea, I found out that autozone sells an adapting kit for a few bucks that I'll just grab today. I plan on hitting the base auto hobby shop after work and giving the core a flush. Im crossing my fingers that this will fix it!

Well, after reading some other threads on similar issues, I have decided to take it to our local Tires Plus, and get them to do a power flush of the system. I figured a pressurized flush would probably do a better job than I could do with a garden hose. I did a double check on the equipment they use (a wynn power flush system) and it looks legit. So, after 1pm today, we'll see if my heat works any better. If not, well... I'll probably be back here looking for advice.

 

cool drop a note how it went, how many dead frogs were pumped out etc

 

Well, it was a success. The heat is now hotter. Not as hot as I would like, but for a 20 year old jeep with probably the original heater core... I think im sitting pretty good. Its definitely quite a bit hotter than the barely lukewarm stuff that it was pumping out.

Oh, and sorry to disappoint, but no dead frogs. Just a cat, a hamster, 2 walruses, and a pheasant. The tech said it was pretty nasty stuff. Which just goes to show that a thorough flush is a good idea.

 

Ok, ran into something odd. The heat, while not as hot as I would like it to be, definitely is NOT as hot when im driving as when I am sitting still. So, any ideas on this? Also, does the temp gauge in the gauge cluster have anything to do with the heater? Or does it just indicate engine temp and that it?

The way I understand it is, the core acts like a radiator and the blower blows the heated fluid in the "radiator" through the vents. Now, what controls the temp output of that heated air? The further you slide the heat control to the right, the hotter the air is supposed to get right? So, what does this? Could my issue be something having to do with this? The T-stat I put in it is brand new, so i dont think its that. And, considering Im getting hot fluid all the way up to the core connections under the hood, I dont think its the stat.

Anyone have any insight?

Oh, also, my temp gauge NEVER touches 210. Its always just barely or half way, between 210 and the line to the left of the 210 mark. My roommate recommended putting some cardboard in front of my rad. I plan on doing this, but it kinda sounds like a bandaid for a broken leg. I mean, if it works it works, but I cant imagine they were meant to work this way.

 

Start new thread ... The guys who may have a good idea about what to check etc simply don't "see" you question/problem
I wish I had an idea, but I don't
I'd guess things to check would be:
-coolant temperature sensor,
-temerature control linkage (to the left/up from passenger's feet),
-is your electric rad. fan spinning all the time?? (also, I don't know is it's possible...heh heh ),

I don't know what else..

 

Good call i'll do that.

 

It`s upside down

 

Here`s an picture

 

uhhhhhhhhh, nice
not only up side down, but also opposite sides, as the "core side" fittings connected to the other side.
ok
from what I "understand" the valve will work either way.
My question: "OR am I completely reversing the directions. ???????" was about the direction of the coolant flow, i.e. from which hose the fluid flows which direction. I still am not sure about it, I kind of think that the last edited diagram should be coreect, but I don't know 100%

 

No it works one direction.